Evaluation of acetone vapors toxicity on Plodia interpunctella (Hubner) (Lepidoptera: Pyralidae) eggs.

PubMed

Pourmirza, Ali Asghr; Nasab, Fershteh Sadeghi; Zadeh, Abas Hossein

2007-08-01

The efficacy of acetone vapors against carefully aged eggs of Plodia interpunctella (Hubner) at 17+/-1 and 27+/-1 degrees C at different dosage levels of acetone over various exposure times was determined. Acetone was found to be toxic to Indian meal moth eggs. Considerable variation in the susceptibility of different age groups of eggs was apparent in the fiducial limits of the LD50 values. An inverse relationship between LD50 values and exposure times was observed in age groups of tested eggs. At 27+/-1 degrees C and 24 h exposure period, eggs aged 1-2 day-old were more tolerant to acetone than other age groups, followed by 0-1 day-old, 2-3 day-old and 3-4 day-old eggs. A similar pattern of susceptibility of eggs was observed at 72 h exposure. In all bioassays, eggs exposed to higher dosages of acetone developed at smaller rate. This was significant for the eggs, which were exposed to the highest dosage for 24 h. Increasing the temperature from 17+/-1 to 27+/-1 degrees C greatly increased the efficacy of acetone. At 27+/-1 degrees C eggs of P. interpunctella were killed by less than one-third of the dosage required for control at 17+/-1 degrees C. Acetone achieved 50% mortality with a dosage of 82.76 mg L(-1) in 1-2 day-old eggs at 27+/-1 degrees C. At this temperature hatching was retarded and greatly diminished when eggs aged 1-2 day-old were exposed to 80 mg L(-1) of acetone for the 24 h exposure period. There was no evidence of a hatch delay longer than the time spent under vapors for eggs exposed at 17+/-1 or 27+/-1 degrees C, indicating that some development must have occurred under fumigation.

The cooling time of fertile chicken eggs at different stages of incubation.

PubMed

Mortola, Jacopo P; Gaonac'h-Lovejoy, Vanda

2016-01-01

We asked whether or not the thermal characteristics of fertile avian eggs changed throughout incubation. The cooling and warming times, expressed by the time constant τ of the egg temperature response to a rapid change in ambient temperature, were measured in fertile chicken eggs at early (E7), intermediate (E11) and late (E20) stages of embryonic development. Same measurements were conducted on eggs emptied of their content and refilled with water by various amounts. The results indicated that (1) the τ of a freshly laid egg was ~50 min; (2) τ decreased linearly with the drop in egg water volume; (3) the dry eggshell had almost no thermal resistance but its wet inner membrane contributed about one-third to the stability of egg temperature; (4) the egg constituents (yolk, albumen and embryonic tissues) and the chorioallantoic circulation had no measurable effect on τ; (5) the presence of an air pocket equivalent in volume to the air cell of fertile eggs reduced τ by about 3 min (E7), 5 min (E11) and 11 min (E20). Hence, in response to warming the egg τ at E20 was slightly shorter than at E7. In response to cooling, the egg τ at E20 was similar to, or longer than, E7 because embryonic thermogenesis (evaluated by measurements of oxygen consumption during cold) offset the reduction in τ introduced by the air cell. In conclusion, until the onset of thermogenesis the thermal behavior of a fertile egg is closely approximated by that of a water-filled egg with an air volume equivalent to the air cell. It is possible to estimate the cooling τ of avian eggs of different species from their weight and incubation time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Incubation times of dinosaur eggs via embryonic metabolism

NASA Astrophysics Data System (ADS)

Lee, Scott A.

2016-08-01

The incubation times for the eggs of 21 dinosaurs are determined from an estimate of their embyronic metabolic rate and the mass of the hatchlings via a mass growth model based on conservation of energy. Embryos in extant birds and crocodiles are studied in order to determine the best model for embryonic metabolism and growth. These results are used to develop a theoretical model that predicts the incubation times of an egg. This model is applied to dinosaur eggs and provides a unique window into dinosaur reproduction. The dinosaurs studied come from both Saurischia and Ornithischia. The incubation times vary from about 28 days for Archaeopteryx lithographica to about 76 days for Alamosaurus sanjuanensis.

Incubation times of dinosaur eggs via embryonic metabolism.

PubMed

Lee, Scott A

2016-08-01

The incubation times for the eggs of 21 dinosaurs are determined from an estimate of their embyronic metabolic rate and the mass of the hatchlings via a mass growth model based on conservation of energy. Embryos in extant birds and crocodiles are studied in order to determine the best model for embryonic metabolism and growth. These results are used to develop a theoretical model that predicts the incubation times of an egg. This model is applied to dinosaur eggs and provides a unique window into dinosaur reproduction. The dinosaurs studied come from both Saurischia and Ornithischia. The incubation times vary from about 28 days for Archaeopteryx lithographica to about 76 days for Alamosaurus sanjuanensis.

Application of the FluEgg model to predict transport of Asian carp eggs in the Saint Joseph River (Great Lakes tributary)

USGS Publications Warehouse

Garcia, Tatiana; Murphy, Elizabeth A.; Jackson, P. Ryan; Garcia, Marcelo H.

2015-01-01

The Fluvial Egg Drift Simulator (FluEgg) is a three-dimensional Lagrangian model that simulates the movement and development of Asian carp eggs until hatching based on the physical characteristics of the flow field and the physical and biological characteristics of the eggs. This tool provides information concerning egg development and spawning habitat suitability including: egg plume location, egg vertical and travel time distribution, and egg-hatching risk. A case study of the simulation of Asian carp eggs in the Lower Saint Joseph River, a tributary of Lake Michigan, is presented. The river hydrodynamic input for FluEgg was generated in two ways — using hydroacoustic data and using HEC-RAS model data. The HEC-RAS model hydrodynamic input data were used to simulate 52 scenarios covering a broad range of flows and water temperatures with the eggs at risk of hatching ranging from 0 to 93% depending on river conditions. FluEgg simulations depict the highest percentage of eggs at risk of hatching occurs at the lowest discharge and at peak water temperatures. Analysis of these scenarios illustrates how the interactive relation among river length, hydrodynamics, and water temperature influence egg transport and hatching risk. An improved version of FluEgg, which more realistically simulates dispersion and egg development, is presented. Also presented is a graphical user interface that facilitates the use of FluEgg and provides a set of post-processing analysis tools to support management decision-making regarding the prevention and control of Asian carp reproduction in rivers with or without Asian carp populations.

Insect eggs protected from high temperatures by limited homeothermy of plant leaves.

PubMed

Potter, Kristen; Davidowitz, Goggy; Woods, H Arthur

2009-11-01

Virtually all aspects of insect biology are affected by body temperature, and many taxa have evolved sophisticated temperature-control mechanisms. All insects, however, begin life as eggs and lack the ability to thermoregulate. Eggs laid on leaves experience a thermal environment, and thus a body temperature, that is strongly influenced by the leaves themselves. Because plants can maintain leaf temperatures that differ from ambient, e.g. by evapotranspiration, plant hosts may protect eggs from extreme ambient temperatures. We examined the degree to which leaves buffer ambient thermal variation and whether that buffering benefits leaf-associated insect eggs. In particular, we: (1) measured temperature variation at oviposition sites in the field, (2) manipulated temperatures in the laboratory to determine the effect of different thermal conditions on embryo development time and survival, and (3) tested embryonic metabolic rates over increasing temperatures. Our results show that Datura wrightii leaves buffer Manduca sexta eggs from fatally high ambient temperatures in the southwestern USA. Moreover, small differences in temperature profiles among leaves can cause large variation in egg metabolic rate and development time. Specifically, large leaves were hotter than small leaves during the day, reaching temperatures that are stressfully high for eggs. This study provides the first mechanistic demonstration of how this type of leaf-constructed thermal refuge interacts with egg physiology.

Don't put all your eggs in one nest: spread them and cut time at risk.

PubMed

Andersson, Malte; Åhlund, Matti

2012-09-01

In many egg-laying animals, some females spread their clutch among several nests. The fitness effects of this reproductive tactic are obscure. Using mathematical modeling and field observations, we analyze an unexplored benefit of egg spreading in brood parasitic and other breeding systems: reduced time at risk for offspring. If a clutch takes many days to lay until incubation and embryo development starts after the last egg, by spreading her eggs a parasitic female can reduce offspring time in the vulnerable nest at risk of predation or other destruction. The model suggests that she can achieve much of this benefit by spreading her eggs among a few nests, even if her total clutch is large. Field data from goldeneye ducks Bucephala clangula show that egg spreading enables a fecund female to lay a clutch that is much larger than average without increasing offspring time at risk in a nest. This advantage increases with female condition (fecundity) and can markedly raise female reproductive success. These results help explain the puzzle of nesting parasites in some precocial birds, which lay eggs in the nests of other females before laying eggs in their own nest. Risk reduction by egg spreading may also play a role in the evolution of other breeding systems and taxa-for instance, polyandry with male parental care in some birds and fishes.

External control of the Drosophila melanogaster egg to imago development period by specific combinations of 3D low-frequency electric and magnetic fields.

PubMed

Makarov, Vladimir I; Khmelinskii, Igor

2016-01-01

We report that the duration of the egg-to-imago development period of the Drosophila melanogaster, and the imago longevity, are both controllable by combinations of external 3-dimensional (3D) low-frequency electric and magnetic fields (LFEMFs). Both these periods may be reduced or increased by applying an appropriate configuration of external 3D LFEMFs. We report that the longevity of D. melanogaster imagoes correlates with the duration of the egg-to-imago development period of the respective eggs. We infer that metabolic processes in both eggs and imago are either accelerated (resulting in reduced time periods) or slowed down (resulting in increased time periods). We propose that external 3D LFEMFs induce electric currents in live systems as well as mechanical vibrations on sub-cell, whole-cell and cell-group levels. These external fields induce media polarization due to ionic motion and orientation of electric dipoles that could moderate the observed effects. We found that the longevity of D. melanogaster imagoes is affected by action of 3D LFEMFs on the respective eggs in the embryonic development period (EDP). We interpret this effect as resulting from changes in the regulation mechanism of metabolic processes in D. melanogaster eggs, inherited by the resulting imagoes. We also tested separate effects of either 3D electric or 3D magnetic fields, which were significantly weaker.

Effects of Temperature on the Termination of Egg Diapause and Post-Diapause Embryonic Development of Galeruca daurica (Coleoptera: Chrysomelidae).

PubMed

Zhou, Xiao-Rong; Gao, Jing-Chun; Pang, Bao-Ping

2016-08-01

Galeruca daurica (Joannis) is a new pest on the grasslands of Inner Mongolia, China. It is univoltine and overwinters in the egg stage. Larvae and adults feed on the foliage of Allium plants. To assess the requirements to terminate egg diapause and subsequent effects on post-diapause development rate, eggs were held at different temperature regimes. Exposure to low temperatures was required to terminate egg diapause. Prolonged exposure (2 mo vs 1 mo) to 5°C and outside ambient conditions (mean temperature: 10.5°C; range: -7.1-21.6°C) enhanced the termination of egg diapause. Prolonged exposure also reduced the time to egg hatch; e.g., eggs held for 2 mo versus 1 mo at 5°C developed more quickly when subsequently placed at warmer temperatures. Egg hatch was observed at 17, 21, 25, and 29°C, but not at 15°C. Regression analysis identified 16.2°C as the minimum temperature for post-diapause development. The temperature requirement to complete embryonic development (from diapause termination to egg hatch) was calculated to be 103.1 to 140.9 degree-days. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

A simple device for measuring the minimum current velocity to maintain semi-buoyant fish eggs in suspension

USGS Publications Warehouse

Mueller, Julia S.; Cheek, Brandon D.; Chen, Qingman; Groeschel, Jillian R.; Brewer, Shannon K.; Grabowski, Timothy B.

2013-01-01

Pelagic broadcast spawning cyprinids are common to Great Plains rivers and streams. This reproductive guild produces non-adhesive semi-buoyant eggs that require sufficient current velocity to remain in suspension during development. Although studies have shown that there may be a minimum velocity needed to keep the eggs in suspension, this velocity has not been estimated directly nor has the influence of physicochemical factors on egg buoyancy been determined. We developed a simple, inexpensive flow chamber that allowed for evaluation of minimum current velocity needed to keep semi-buoyant eggs in suspension at any time frame during egg development. The device described here has the capability of testing the minimum current velocity needed to keep semi-buoyant eggs in suspension at a wide range of physicochemical conditions. We used gellan beads soaked in freshwater for 0, 24, and 48 hrs as egg surrogates and evaluated minimum current velocities necessary to keep them in suspension at different combinations of temperature (20.0 ± 1.0° C, 25.0 ± 1.0° C, and 28.0 ± 1.0° C) and total dissolved solids (TDS; 1,000 mg L-1, 3,000 mg L-1, and 6,000 mg L-1). We found that our methodology generated consistent, repeatable results within treatment groups. Current velocities ranging from 0.001–0.026 needed to keep the gellan beads in suspension were negatively correlated to soak times and TDS and positively correlated with temperature. The flow chamber is a viable approach for evaluating minimum current velocities needed to keep the eggs of pelagic broadcast spawning cyprinids in suspension during development.

Biotechnology

NASA Image and Video Library

2003-01-22

The Avian Development Facility (ADF) supports 36 eggs in two carousels, one of which rotates to provide a 1-g control for comparing to eggs grown in microgravity. The ADF was designed to incubate up to 36 Japanese quail eggs, 18 in microgravity and 18 in artificial gravity. The two sets of eggs were exposed to otherwise identical conditions, the first time this is been accomplished in space. Eggs are preserved at intervals to provide snapshots of their development for later analysis. Quails incubate in just 15 days, so they are an ideal species to be studied within the duration of space shuttle missions. Further, several investigators can use the same specimens to address different questions. The ADF originated in NASA's Shuttle Student Involvement program in the 1980s and was developed under the NASA Small Business Irnovation Research program. In late 2001, the ADF made its first flight and carried eggs used in two investigations.

The influence of encapsulated embryos on the timing of hatching in the brooding gastropod Crepipatella dilatata

NASA Astrophysics Data System (ADS)

Andrade-Villagrán, P. V.; Baria, K. S.; Montory, J. A.; Pechenik, J. A.; Chaparro, O. R.

2018-01-01

Encapsulated embryos are generally thought to play an active role in escaping from egg capsules or egg masses. However, for species that brood their egg capsules, the factors controlling the timing of hatching are largely unclear, particularly the degree to which hatching is controlled by the embryos rather than by the mother, and the degree to which the hatching of one egg capsule influences the hatching of sister egg capsules within the same egg mass. We studied aspects of hatching using the direct-developing gastropod Crepipatella dilatata, which includes nurse eggs in its egg capsules and broods clusters of egg capsules for at least several weeks before metamorphosed juveniles are released. Isolated egg capsules were able to hatch successfully, in the absence of the mother. Moreover, the hatching of one capsule did not cause adjacent sister capsules to hatch. Hatched and un-hatched sister egg capsules from the same egg mass differed significantly in the number of metamorphosed juveniles, average shell size, offspring biomass (juveniles + veliger larvae), and the number of nurse eggs remaining per egg capsule. Differences in when egg capsules hatched within a single egg mass were not explained by differences in egg capsule age. Hatching occurred only after most nurse eggs had been ingested, most offspring had metamorphosed into juveniles, and juveniles had reached a mean shell length > 1.36 mm. Whether the mother has any role to play in coordinating the hatching process or juvenile release remains to be determined.

Ovicidal activity of acrolein vapors to Indian meal moth eggs of various ages.

PubMed

Pourmirza, Ali Asghr

2007-09-01

The effect of acrolein vapors against carefully aged eggs of Indian meal moth at 27 +/- 1 and 17 +/- 1 degrees C at different dosage levels of acrolein over various exposure times was determined. Considerable variation in the susceptibility of different age groups of eggs was apparent in the fiducial limits of the LD50 values. At both temperatures and 24 h exposure period, eggs aged 1-2 day-old were more tolerant to acrolein than other age groups. In all bioassays, eggs exposed to higher dosages of acrolein developed at smaller rate. This was significant for the eggs, which were exposed to the highest dosage for 24 h. Increasing the temperature from 17 +/- 1 to 27 +/- 1 degrees C greatly increased the efficacy of acrolein. Overall, at 27 +/- 1 degrees C eggs of P. interpunctella were killed by less than one-fourth of the dosage required for control at 17 +/- 1 degrees C. Acrolein achieved 50% mortality with a dosage of 3.80 mg L(-1) in 1-2 day-old eggs at 27 +/- 1 degrees C. At this temperature hatching was retarded and greatly reduced when eggs aged 1-2 day-old were exposed to 32 mg L(-1) of acrolein for the 24 h exposure period. There was no evidence of a hatch delay longer than the time spent under vapors for eggs exposed at 17 +/- 1 or 27 +/- 1 degrees C, indicating that some development must have occurred under fumigation.

A real time quality control application for animal production by image processing.

PubMed

Sungur, Cemil; Özkan, Halil

2015-11-01

Standards of hygiene and health are of major importance in food production, and quality control has become obligatory in this field. Thanks to rapidly developing technologies, it is now possible for automatic and safe quality control of food production. For this purpose, image-processing-based quality control systems used in industrial applications are being employed to analyze the quality of food products. In this study, quality control of chicken (Gallus domesticus) eggs was achieved using a real time image-processing technique. In order to execute the quality control processes, a conveying mechanism was used. Eggs passing on a conveyor belt were continuously photographed in real time by cameras located above the belt. The images obtained were processed by various methods and techniques. Using digital instrumentation, the volume of the eggs was measured, broken/cracked eggs were separated and dirty eggs were determined. In accordance with international standards for classifying the quality of eggs, the class of separated eggs was determined through a fuzzy implication model. According to tests carried out on thousands of eggs, a quality control process with an accuracy of 98% was possible. © 2014 Society of Chemical Industry.

ELECTRIC IMPEDANCE OF HIPPONOË EGGS

PubMed Central

Cole, Kenneth S.

1935-01-01

Alternating current resistance and capacity measurements have been made from 1.08 103 to 2.32 106 cycles per second on suspensions of unfertilized, fertilized, and swollen unfertilized eggs of the echinoderm Hipponoë esculenta. A simple method has been developed for measuring the volume concentration of eggs in a suspension. The membrane of the unfertilized egg is practically non-conducting at low frequencies and shows a static capacity of 0.87 µf/cm.2 except perhaps at the highest frequencies. The equivalent specific resistance of the egg interior is 11 times that of sea water. The membrane of the fertilized egg is practically non-conducting at low frequencies and shows a static capacity 2.5 times that of the unfertilized egg except at the higher frequencies where another reactive element produces a marked effect. The internal resistance is apparently higher than that of the unfertilized egg. The static capacity per unit area of the membrane decreases as a linear function of the surface area when the eggs are swollen in dilute sea water. In 40 per cent sea water, the capacity falls to about 75 per cent of normal. PMID:19872897

Effect of temperature during embryonic development and first feeding of Trichogaster leeri larvae.

PubMed

Pereira, Samuel Louzada; de Andrade, Dalcio Ricardo; Radael, Marcella Costa; Fosse Filho, João Carlos; de Azevedo, Rafael Vieira; Mattos, Douglas da Cruz; Vidal Junior, Manuel Vazquez

2016-10-01

Temperature is an environmental factor that influences the development of fish, and when changed abruptly can lead to high mortality. Some species of fish are influenced by this factor, exhibiting a longer time for embryonic development and time to first feeding. This study aims to evaluate the effect of water temperature on embryonic and larval development up to first feeding, to describe the time in hours post fertilization (hpf) of the emergence of different structures and to determine the best hatching rate and survival of animals under different treatments. Five different egg incubation temperatures were used (24, 26, 28, 30 or 32°C, respectively). The eggs were observed at regular intervals of 30 min up to 24 h, every 2 h until 48 h and every 4 h until the display of first feeding in all treatments. Embryonic development was longer for eggs incubated at 24°C and the best results for hatching rate and survival of spawning efficiency were at 28°C. We recommend that incubation of Trichogaster leeri eggs is carried out at 28°C up to the first feeding of larvae.

Divergent Egg Physiologies in Two Closely Related Grasshopper Species: Taeniopoda eques versus Romalea microptera (Orthoptera: Romaleidae)

PubMed Central

STAUFFER, TIMOTHY W.; HATLE, JOHN D.; WHITMAN, DOUGLAS W.

2013-01-01

We compared egg survivorship and egg development time at different soil moistures for two closely related grasshopper species from divergent habitats: marsh-inhabiting Romalea microptera (Beauvois) versus desert-inhabiting Taeniopoda eques (Burmeister). These two species can interbreed and produce viable offspring. In nature, both species have a similar 8–9 mo subterranean egg stage, but their soil environments differ dramatically in water content. We predicted that the eggs of the two species would exhibit differential survivorship and development times under different moisture levels. Our laboratory results show that the eggs of both species survived a wide range of soil moistures (≈ 0.5 to 90%), maintained for 3 mo. However, the eggs of the marsh grasshopper, R. microptera, better tolerated the highest soil moistures (95 and 100%), whereas the eggs of the desert species, T. eques, better tolerated the lowest soil moistures (0.0 and 0.1%). Sixty-five percent of marsh-inhabiting R. microptera eggs, but no desert T. eques eggs, survived 3 mo submersion under water. In contrast, 49% of desert T. eques eggs, but only 3.5% of R. microptera eggs, survived after being laid into oven-dried sand and then maintained with no additional water until hatch. In the laboratory at 26°C, the two species differed significantly in the mean length of the oviposition-to-hatch interval: 176 d for R. microptera versus 237 d for T. eques. These divergent traits presumably benefit these insects in their divergent habitats. Our results suggest the evolution of physiological divergence that is consistent with adaptations to local environments. PMID:22182625

Resuspension and settling of helminth eggs in water: Interactions with cohesive sediments.

PubMed

Sengupta, Mita E; Andersen, Thorbjørn J; Dalsgaard, Anders; Olsen, Annette; Thamsborg, Stig M

2012-08-01

Helminth parasite eggs in low quality water represent main food safety and health hazards and are therefore important indicators used to determine whether such water can be used for irrigation. Through sedimentation helminth eggs accumulate in the sediment, however resuspension of deposited helminth eggs will lead to increased concentration of suspended eggs in the water. Our study aimed to determine the erodibility (erosion rate and erosion threshold) and settling velocity of Ascaris and Trichuris eggs as well as cohesive sediment at different time points after incorporation into the sediment. Cohesive sediment collected from a freshwater stream was used to prepare a sediment bed onto which helminth eggs were allowed to settle. The erodibility of both sediment and helminth eggs was found to decrease over time indicating that the eggs were incorporated into the surface material of the bed and that this material was stabilized through time. This interaction between eggs and bulk sediment was further manifested in an increased settling velocity of suspended eggs when sediment was present in the suspension as compared to a situation with settling in clean water. The incorporation into the sediment bed and the aggregation with sediment particles decrease the mobility of both helminth egg types. Our findings document that helminth eggs should not be viewed as single entities in water systems when modelling the distribution of eggs since both erodibility and settling velocity of eggs are determined by mobility of the sediment present in the water stream. Recalculation of the erosion threshold for helminth eggs and sediment showed that even at relatively low current velocities i.e. 0.07-0.12ms(-1) newly deposited eggs will be mobile in open irrigation channels. These environmental factors affecting resuspension must be taken into account when developing models for sedimentation of helminth eggs in different water systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effects of ambient temperature on egg and larval development of the invasive emerald ash borer (Coleoptera: Buprestidae): implications for laboratory rearing.

PubMed

Duan, Jian J; Watt, Tim; Taylor, Phil; Larson, Kristi; Lelito, Jonathan P

2013-10-01

The emerald ash borer, Agrilus planipennis Fairmaire, an invasive beetle from Asia causing large scale ash (Fraxinus) mortality in North America, has been extremely difficult to rear in the laboratory because of its long life cycle and cryptic nature of immature stages. This lack of effective laboratory-rearing methods has not only hindered research into its biology and ecology, but also mass production of natural enemies for biological control of this invasive pest. Using sticks from the alternate host plant, Fraxinus uhdei (Wenzig) Lingelsh, we characterized the stage-specific development time and growth rate of both emerald ash borer eggs and larvae at different constant temperatures (12-35 degrees C) for the purpose of developing effective laboratory-rearing methods. Results from our study showed that the median time for egg hatching decreased from 20 d at 20 degrees C to 7 d at 35 degrees C, while no emerald ash borer eggs hatched at 12 degrees C. The developmental time for 50% of emerald ash borer larvae advancing to third, fourth, and J-larval stages at 20 degrees C were 8.3, 9.1, and 12.3 wk, respectively, approximately two times longer than at 30 degrees C for the corresponding instars or stages. In contrast to 30 degrees C, however, the development times of emerald ash borer larvae advancing to later instars (from oviposition) were significantly increased at 35 degrees C, indicating adverse effects of this high temperature. The optimal range of ambient temperature to rear emerald ash borer larvae should be between 25-30 degrees C; however, faster rate of egg and larval development should be expected as temperature increases within this range.

Determination of allergenic egg proteins in food by protein-, mass spectrometry-, and DNA-based methods.

PubMed

Lee, Ji-Yun; Kim, Chang Jong

2010-01-01

Egg allergy is one of the most common food allergies in both adults and children, and foods including eggs and their byproducts should be declared under food allergen labeling policies in industrial countries. Therefore, to develop and validate a sensitive and specific method to detect hidden egg allergens in foods, we compared immunochemical, DNA-based, and proteomic methods for detecting egg allergens in foods using egg allergen standards such as egg whole protein, egg white protein, egg yolk protein, ovomucoid, ovalbumin, ovotransferrin, lysozyme, and alpha-livetin. Protein-based immunochemical methods, including ELISA as an initial screening quantitative analysis and immunoblotting as a final confirmatory qualitative analysis, were very sensitive and specific in detecting potentially allergenic egg residues in processed foods in trace amounts. In contrast, the proteomics-based, matrix-assisted laser desorption/ionization time-of-flight MS and LC-tandem quadrupole time-of-flight MS methods were not able to detect some egg allergens, such as ovomucoid, because of its nondenaturing property under urea and trypsin. The DNA-based PCR method could not distinguish between egg and chicken meat because it is tissue-nonspecific. In further studies for the feasibility of these immunochemical methods on 100 real raw dietary samples, four food samples without listed egg ingredients produced a positive response by ELISA, but exhibited negative results by immunoblotting.

The environmental neurotoxin β-N-methylamino-l-alanine (l-BMAA) is deposited into birds' eggs.

PubMed

Andersson, Marie; Karlsson, Oskar; Brandt, Ingvar

2018-01-01

The neurotoxic amino acid β-N-methylamino-L-alanine (BMAA) has been implicated in the etiology of neurodegenerative disorders. BMAA is also a known developmental neurotoxin and research indicates that the sources of human and wildlife exposure may be more diverse than previously anticipated. The aim of the present study was therefore to examine whether BMAA can be transferred into birds' eggs. Egg laying quail were dosed with 14 C-labeled BMAA. The distribution of radioactivity in the birds and their laid eggs was then examined at different time points by autoradiography and phosphoimaging analysis. To evaluate the metabolic stability of the BMAA molecule, the distribution of 14 C-methyl- and 14 C-carboxyl-labeled BMAA were compared. The results revealed a pronounced incorporation of radioactivity in the eggs, predominantly in the yolk but also in the albumen. Imaging analysis showed that the concentrations of radioactivity in the liver decreased about seven times between the 24h and the 72h time points, while the concentrations in egg yolk remained largely unchanged. At 72h the egg yolk contained about five times the concentration of radioactivity in the liver. Both BMAA preparations gave rise to similar distribution pattern in the bird tissues and in the eggs, indicating metabolic stability of the labeled groups. The demonstrated deposition into eggs warrants studies of BMAAs effects on bird development. Moreover, birds' eggs may be a source of human BMAA exposure, provided that the laying birds are exposed to BMAA via their diet. Copyright © 2017 Elsevier Inc. All rights reserved.

Larval and adult environmental temperatures influence the adult reproductive traits of Anopheles gambiae s.s.

PubMed

Christiansen-Jucht, Céline D; Parham, Paul E; Saddler, Adam; Koella, Jacob C; Basáñez, María-Gloria

2015-09-17

Anopheles mosquito life-history parameters and population dynamics strongly influence malaria transmission, and environmental factors, particularly temperature, strongly affect these parameters. There are currently some studies on how temperature affects Anopheles gambiae s.s. survival but very few exist examining other life-history traits. We investigate here the effect of temperature on population dynamics parameters. Anopheles gambiae s.s. immatures were reared individually at 23 ± 1 °C, 27 ± 1 °C, 31 ± 1 °C, and 35 ± 1 °C, and adults were held at their larval temperature or at one of the other temperatures. Larvae were checked every 24 h for development to the next stage and measured for size; wing length was measured as a proxy for adult size. Females were blood fed three times, and the number of females feeding and laying eggs was counted. The numbers of eggs and percentage of eggs hatched were recorded. Increasing temperatures during the larval stages resulted in significantly smaller larvae (p = 0.005) and smaller adults (p < 0.001). Adult temperature had no effect on the time to egg laying, and the larval temperature of adults only affected the incubation period of the first egg batch. Temperature influenced the time to hatching of eggs, as well as the time to development at every stage. The number of eggs laid was highest when adults were kept at 27 °C, and lowest at 31 °C, and higher adult temperatures decreased the proportion of eggs hatching after the second and third blood meal. Higher adult temperatures significantly decreased the probability of blood feeding, but the larval temperature of adults had no influence on the probability of taking a blood meal. Differences were observed between the first, second, and third blood meal in the times to egg laying and hatching, number of eggs laid, and probabilities of feeding and laying eggs. Our study shows that environmental temperature during the larval stages as well as during the adult stages affects Anopheles life-history parameters. Data on how temperature and other climatic factors affect vector life-history parameters are necessary to parameterise more reliably models predicting how global warming may influence malaria transmission.

Time-measurement-regulating peptide PIN may alter a timer conformation of Time Interval Measuring Enzyme (TIME).

PubMed

Ti, Xiaonan; Tani, Naoki; Isobe, Minoru; Kai, Hidenori

2006-05-01

The TIME (Time Interval Measuring Enzyme) ATPase measures time intervals in accordance with diapause development, which indispensably requires cold for resumption of embryonic development in the silkworm (Bombyx mori). The PIN (Peptidyl Inhibitory Needle) peptide regulates the time measurement function of TIME. In the present study we investigated the interaction between TIME and PIN in order to address the mechanism of diapause development. When TIME was isolated from eggs later than 12 days after oviposition, transient bursts of ATPase activity occurred 18h after isolation of TIME, and the younger the eggs and pupal ovaries from which TIME was isolated, the earlier the bursts of ATPase activity appeared. However, no interval-timer activation of ATPase occurred in ovaries earlier than 6 days after pupation. Similar patterns of ATPase activity occurred in test tubes after mixing TIME with PIN. The shorter the time PIN was mixed with TIME, the earlier the ATPase activity appeared. The timer may be built into the protein conformation of TIME, and PIN (which is present in ovaries beginning 6 days after pupation) appears able to alter this timer conformation through pupal stages to laid eggs. We discuss the possible mechanism of diapause development in relation to the timer mechanism of TIME.

Interspecific interaction between Telenomus remus (Hymenoptera: Platygastridae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs.

PubMed

Carneiro, Tatiana R; Fernandes, Odair A

2012-12-01

This work aims to evaluate the interspecific interaction between Trichogramma pretiosum and Telenomus remus, two biological control agents of fall armyworm (Spodoptera frugiperda) eggs. Eggs of Spodoptera frugiperda previously parasitized by Telenomus remus were offered to Trichogramma pretiosum, and those parasitized by Trichogramma pretiosum were offered to Telenomus remus. The previously parasitized eggs were tested at different embryonic development stages for each parasitoid. In addition, to evaluate the competition between species, Spodoptera frugiperda eggs were offered to the parasitoids simultaneously. The behavior of the insects was recorded under a stereomicroscope. When Spodoptera frugiperda eggs were previously exposed to either parasitoid, there was no emergence of the other parasitoid. When the Telenomus remus and Trichogramma pretiosum females were placed together with Spodoptera frugiperda eggs, Telenomus remus had a greater parasitism rate. Except searching time, all Trichogramma pretiosum behaviors took a longer time than Telenomus remus behaviors. Thus, despite belonging to different families, each of these parasitoids is able to recognize host eggs previously parasitized by the other. So, this suggests that the recognition mechanism involved is not exclusively specific.

Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure.

PubMed

Yan, Yan; Williams, Scott B; Baributsa, Dieudonne; Murdock, Larry L

2016-06-17

Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres-2%, 5% and 10% (v/v) oxygen-and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny.

Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure

PubMed Central

Yan, Yan; Williams, Scott B.; Baributsa, Dieudonne; Murdock, Larry L.

2016-01-01

Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres—2%, 5% and 10% (v/v) oxygen—and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny. PMID:27322332

The relationship of oocyte diameter and incubation temperature to incubation time in temperate freshwater fish species.

PubMed

Teletchea, F; Gardeur, J-N; Kamler, E; Fontaine, P

2009-02-01

Based on the analysis of six egg variables and incubation temperature of 65 temperate freshwater fish species, the possible relationships between oocyte diameter, incubation time and incubation temperature were reassessed and compared to the results obtained from marine fishes. Most freshwater species have eggs (mean +/-s.d. 2.19 +/- 1.52 mm) larger than marine species, that are chiefly demersal and develop stuck to various substrata, such as plants or rocks. A strong negative relationship was found between incubation time (t, days) and incubation temperature (T, degrees C): t = 186.23e(-0.197T) (r(2)= 0.87). A strong dependence of incubation time on oocyte diameter (Ø, mm) and incubation temperature was also found and was defined as: log(10)t= 3.002 + 0.599 log(10)Ø - 1.91 log(10) (T + 2), which explained 92% of the variance of the data set. Five major groups of species were defined based on the principal component analysis (PCA) of four quantitative variables. There were two distinct groups of salmonids, displaying demersal and non-adhesive eggs with a long incubation time at low temperature, the eggs of which required a high number of degree-days. There was a large group of species possessing small, mostly demersal and adhesive eggs developing at high temperature during a short period of time, and requiring a low number of degree-days. Between these two extremes, there was a fourth group displaying intermediate values and a fifth group including three species with large, adhesive and demersal eggs incubating at high temperatures during a short period of time. The burbot Lota lota displayed an unusual combination of variables compared to the remaining species in the data set.

Geographic variation in avian incubation periods and parental influences on embryonic temperature

USGS Publications Warehouse

Martin, T.E.; Auer, S.K.; Bassar, R.D.; Niklison, Alina M.; Lloyd, P.

2007-01-01

Theory predicts shorter embryonic periods in species with greater embryo mortality risk and smaller body size. Field studies of 80 passerine species on three continents yielded data that largely conflicted with theory; incubation (embryonic) periods were longer rather than shorter in smaller species, and egg (embryo) mortality risk explained some variation within regions, but did not explain larger differences in incubation periods among geographic regions. Incubation behavior of parents seems to explain these discrepancies. Bird embryos are effectively ectothermic and depend on warmth provided by parents sitting on the eggs to attain proper temperatures for development. Parents of smaller species, plus tropical and southern hemisphere species, commonly exhibited lower nest attentiveness (percent of time spent on the nest incubating) than larger and northern hemisphere species. Lower nest attentiveness produced cooler minimum and average embryonic temperatures that were correlated with longer incubation periods independent of nest predation risk or body size. We experimentally tested this correlation by swapping eggs of species with cool incubation temperatures with eggs of species with warm incubation temperatures and similar egg mass. Incubation periods changed (shortened or lengthened) as expected and verified the importance of egg temperature on development rate. Slower development resulting from cooler temperatures may simply be a cost imposed on embryos by parents and may not enhance offspring quality. At the same time, incubation periods of transferred eggs did not match host species and reflect intrinsic differences among species that may result from nest predation and other selection pressures. Thus, geographic variation in embryonic development may reflect more complex interactions than previously recognized. ?? 2007 The Author(s).

Eggshell porosity covaries with egg size among female House Wrens (Troglodytes aedon) but is unrelated to incubation onset and egg-laying order within clutches.

PubMed

Bowers, E K; White, A; Lang, A; Podgorski, L; Thompson, C F; Sakaluk, S K; Jaeckle, W B; Harper, R G

2015-06-01

In birds, the duration of egg incubation (the time from incubation onset to hatching) can affect multiple components of nest success, but what affects incubation duration? Previous studies suggest that incubation duration is affected by both parental behavior and components of the egg, which have yet to be determined. One egg component that may be related to incubation behavior and the time until hatching is eggshell porosity, which affects the exchange of metabolic gasses and water vapor across the shell and, thus, the speed of embryonic development and incubation duration. We tested whether eggshell porosity was associated with the timing of incubation onset by female House Wrens ( Troglodytes aedon Vieillot, 1809), and whether porosity varied within clutches in a manner that might be associated with incubation periods and hatching patterns (i.e., synchronous vs. asynchronous hatching). Eggshell porosity was unrelated to the onset of maternal incubation and did not differ between early and later-laid eggs within clutches, but differed significantly among females and covaried with egg size. We conclude that producing all eggshells of similar porosity within clutches, while adjusting incubation onset once most or all eggs are laid, provide facultative maternal control over variation in hatching patterns.

Toxicity of pesticides associated with potato production, including soil fumigants, to snapping turtle eggs (Chelydra serpentina).

PubMed

de Solla, Shane Raymond; Palonen, Kimberley Elizabeth; Martin, Pamela Anne

2014-01-01

Turtles frequently oviposit in soils associated with agriculture and, thus, may be exposed to pesticides or fertilizers. The toxicity of a pesticide regime that is used for potato production in Ontario on the survivorship of snapping turtle (Chelydra serpentina) eggs was evaluated. The following treatments were applied to clean soil: 1) a mixture of the pesticides chlorothalonil, S-metolachlor, metribuzin, and chlorpyrifos, and 2) the soil fumigant metam sodium. Turtle eggs were incubated in soil in outdoor plots in which these mixtures were applied at typical and higher field application rates, where the eggs were subject to ambient temperature and weather conditions. The pesticide mixture consisting of chlorothalonil, S-metolachlor, metribuzin, and chlorpyrifos did not affect survivorship, deformities, or body size at applications up to 10 times the typical field application rates. Hatching success ranged between 87% and 100% for these treatments. Metam sodium was applied at 0.1¯ times, 0.3¯ times, 1 times, and 3 times field application rates. Eggs exposed to any application of metam sodium had 100% mortality. At typical field application rates, the chemical regime associated with potato production does not appear to have any detrimental impacts on turtle egg development, except for the use of the soil fumigant metam sodium, which is highly toxic to turtle eggs at the lowest recommended application rate. © 2013 SETAC.

Physical and chemical changes in the foreshore of an estuarine beach: Implications for viability and development of horseshoe crab Limulus polyphemus eggs

USGS Publications Warehouse

Jackson, N.L.; Smith, D.R.; Nordstrom, K.F.

2008-01-01

Knowledge of conditions that favor development of eggs is important for management of species whose population growth is sensitive to early life history survival. Viability and development of the eggs of horseshoe crabs Limulus polyphemus on a sand and gravel beach were evaluated using data gathered on Delaware Bay, USA, from 18 May to 19 June 2004. Eggs were transplanted to pouches and buried in the foreshore for up to 6 wk. Viability and developmental stage were estimated as a function of oxygen and temperature gradients across the foreshore. These gradients were related to the characteristics of the intertidal foreshore sediments, beach water table changes, and frequency of inundation due to tide and swash/backwash processes. Results demonstrate the importance of interstitial temperature for development to larvae and the passive role of sediment characteristics on moisture retention and temperature. Percentage of eggs remaining in egg stage was similar across the foreshore, but more eggs developed to embryos at 0.45 of foreshore width, where moisture and gravel content were greater and interstitial temperature was lower. More eggs developed to larvae at 0.60 and 0.75 of foreshore width, where moisture and gravel content were less but interstitial temperature was higher. The beach above 0.75 of foreshore width came under the influence of wave action or full tidal inundation only during high wave heights or spring tides, and pouches at 0.75 of foreshore width were inundated only 19% of the time. Periodic wetting at this elevation did not reduce overall viability of the eggs. High wave energy events resulted in sediment activation depths to pouches at 0.30 of foreshore width, where loss of eggs due to wave activation was the most important control on the development of eggs. ?? Inter-Research 2008.

When Is Embryonic Arrest Broken in Turtle Eggs?

PubMed

Williamson, Sean A; Evans, Roger G; Reina, Richard D

Turtle embryos enter a state of arrested development in the oviduct, allowing the mother greater flexibility in her reproductive schedule. Development recommences once eggs transition from the hypoxic oviduct to the normoxic nest. Significant mortality can occur if turtle eggs are moved between 12 h and 20 d after oviposition, and this is linked to the recommencement of embryonic development. To better understand the timing of developmental arrest and to determine how movement-induced mortality might be avoided, we determined the latency (i.e., time elapsed since oviposition) to recommencement of development following oviposition by exposing the eggs of green turtles (Chelonia mydas) to hypoxia (oxygen tension <8 mmHg) for 3 d, commencing 30 min to 48 h after oviposition. Embryonic development-including development of the characteristic opaque white spot on the eggshell-was halted by hypoxic incubation. When the delay before hypoxic incubation was 12 h or less, hatching success did not differ from a control group. If the hypoxic treatment began after 16 h or more in normoxia, then all embryos died. Thus, by returning eggs to a hypoxic environment before they have broken from arrest (i.e., within 12 h of oviposition), it is possible to extend embryonic arrest for at least 3 d, with no apparent detriment to hatching success. Therefore, hypoxic incubation may provide a new approach for avoidance of movement-induced mortality when conservation or research efforts require the relocation of eggs. Our findings also suggest that movement-induced mortality may have constrained the evolution of viviparity in turtles.

Seasonal Synchronization of Diapause Phases in Aedes albopictus (Diptera: Culicidae).

PubMed

Lacour, Guillaume; Chanaud, Lionel; L'Ambert, Grégory; Hance, Thierry

2015-01-01

In temperate areas, population dynamics of the invasive Asian tiger mosquito Aedes albopictus are strongly affected by winter. The work we present here analyzes the adaptive synchronization of the diapause process in the wintry generation of A. albopictus, where the egg stage is exposed to adverse winter conditions. The seasonal pattern of egg laying activity of a French Mediterranean population of the Asian tiger mosquito was monitored weekly for 2 years with ovitraps. The field diapause incidence and the critical photoperiod (CPP, i.e. the maternal day length inducing diapause in 50% of the eggs), were determined by hatching experiments on the collected eggs. The period of diapause termination was estimated by a field survey of the first hatchings for both years. The CPP is equal to 13.5 hours of light and occurs in the field on the 25th of August. Thus, it is on September 11th, 17 days after the CPP, that 50% of the eggs are in a prediapause stage in the field. The egg diapause rate increases rapidly during September, whereas the mean number of eggs laid decreases sharply after mid-September. Surprisingly, after having reached a peak of 95% at the end of September, from mid-October the diapause incidence declined and stayed below 50%. Indeed, both years the diapause initiates before the rapid decrease of the environmental temperature. This leaves a sufficient period of time to the complete development of one generation of A. albopictus with effective induction of diapause in the laid eggs. The very first larvae hatched were sampled both years in the first half of March. With 20 to 26 weeks in the egg stage and about 7 weeks in the larval stages, the first annual generation spends a long time in immature stages. On a practical point of view, this long development time represents a wide window for eggs and larvae control in early spring.

Parthenogenesis in mated Chinese Painted quail (Coturnix chinensis) hens decreases sperm-egg penetration and alters albumen characteristics.

PubMed

Santa Rosa, P; Parker, H M; Kiess, A S; McDaniel, C D

2016-10-15

Parthenogenesis, embryonic development without fertilization, resembles very early embryonic mortality in fertilized eggs. Also, parthenogenesis alters egg albumen characteristics in virgin Chinese Painted quail hens genetically selected for parthenogenesis (PV). When these PV hens are mated (PM), hatchability is reduced versus control mated (CM) hens that were not genetically selected for parthenogenesis. However, it is unclear if parthenogenesis, which occurs in PM hens, reduces hatchability due to infertility and altered albumen characteristics. Sperm-egg penetration (SEP) holes are indicative of true fertilization and may be useful in identifying if eggs from PM hens exhibit a decrease in fertility versus CM hens. Therefore, the objectives of this study were to determine if parthenogenesis in PM hens (1) decreases SEP, (2) alters albumen characteristics similar to parthenogenesis in eggs from PV hens, and (3) yields albumen characteristics similar to fertilized eggs containing early mortality. Daily, PV and PM eggs were collected, labeled, and incubated for 10 days, then broken out to determine the incidence of parthenogenesis and albumen characteristics. Also daily, fresh PM and CM quail eggs were macroscopically examined to determine if an egg was infertile with no embryonic development, parthenogenetic, or fertile. Each of these eggs was then microscopically examined for SEP. For both PV and PM incubated eggs, parthenogenesis decreased albumen pH, O2, and protein concentrations yet increased Ca(2+) and CO2 concentrations versus eggs with no development. For incubated PM eggs, albumen pH and O2 were lower, yet CO2 was higher for eggs containing parthenogens or early dead embryos versus infertile eggs. For SEP, fresh eggs classified as infertile or parthenogenetic from PM and CM hens had similar SEP holes but only one sixth as many SEP holes as eggs classified as fertilized. Eggs from CM hens had 3.5 times as many SEP holes as PM eggs. In conclusion, parthenogenesis that occurs in mated quail hens inhibits fertility and alters albumen characteristics similarly to parthenogenesis in unfertilized eggs and early embryonic mortality in fertilized eggs. Copyright © 2016 Elsevier Inc. All rights reserved.

Assessment of the risk of salmonellosis from internally contaminated shell eggs following initial storage at 18 °C (65 °F), compared with 7 °C (45 °F).

PubMed

Pouillot, R; Hoelzer, K; Ramirez, G A; deGraft-Hanson, J; Dennis, S B

2014-10-01

In the U.S., chicken-breeder farms that supply hatcheries typically store and transport eggs intended for broiler production at a temperature of 18.3 °C (65 °F). However, in case of surplus, some of these eggs may be diverted to human consumption. According to the U.S. Food and Drug Administration's 'Egg Safety Final Rule,' shell eggs intended for human consumption are required to be held or transported at or below 7.2 °C (45 °F) ambient temperature beginning 36 h after time of lay. We adapted a risk assessment model developed by the U.S. Department of Agriculture's Food Safety Inspection Service, to quantify human exposure to Salmonella Enteritidis and the risk of human salmonellosis if eggs are held and transported at 18.3 °C for up to 5.5 days after time of lay, as has been observed when hatchery eggs are diverted to human consumption, rather than held and transported at 7.2 °C within 36 h after time of lay. Storage at 18.3 °C leads to considerable bacterial growth in internally contaminated eggs. The model predicted that more than 10% of internally contaminated eggs would remain contaminated after in-shell pasteurization resulting in a 5-log10 reduction, and that some bacteria would survive after home-cooking. The model predicted that, alternatively, eggs stored at 7.2 °C after lay would have limited bacterial growth prior to pasteurization, and Salmonella would be very unlikely to be present after pasteurization. The predicted risk of salmonellosis from the consumption of eggs held and transported at 18.3 °C and subsequently diverted to human consumption is 25 times higher than the risk when eggs are held and transported at 7.2 °C. Published by Elsevier Ltd.

Effects of temperature on the development and survival of eggs of four coastal California fishes

USGS Publications Warehouse

Gadomski, D.M.; Caddell, S.M.

1996-01-01

Laboratory experiments were conducted to determine the effects of temperature on egg development and survival of four fish species found off southern California. Our objectives were to further understanding ofnatural spawning patterns and to aid in identifying and ageing field-collected specimens. An egg-staging procedure was devised and eggs were observed every two hours during development at a range of temperatures (8-28°Cl. Barred sand bass, Parolabrax nebulifer, eggs survived to hatching and produced viable embryos at the highest temperature range (l6-28°C), reflecting this species'summerspawning season. Fantail sole, Xystreurys liolepis, eggs also hatched at a higher temperature range (l6-24°C). This species spawns primarily from summer through fall. Eggs of the two species with winter-spring spawning peaks, white croaker, Genyonemuslineatus, and California halibut, Paralichthys californicus, had lower temperature-tolerance ranges (12- 2O"C). Developmental rate at a specific temperature did not significantly differ between species, whereas within tolerance limits, temperature strongly affected rate of development for all species. Time to hatching for all species was inversely related to temperature, and the relationship was approximately exponential. Species-specific differences in egg-stage sequence were observed; embryonic organogenesisin relation to germ-ring migration and blastopore closure was faster for barred sand bass and fantail sole than for white croaker and California halibut.

[Biology and thermal requirements of Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) parasitizing eggs of Diaphania hyalinata L. (Lepidoptera: Pyralidae)].

PubMed

Melo, Ricardo L; Pratissoli, Dirceu; Polanczyk, Ricardo A; Melo, Débora F; Barros, Reginaldo; Milanez, André M

2007-01-01

The development and parasitism of Diaphania hyalinata L. eggs by Trichogramma atopovirilia Oatman & Platner and its thermal requirements were studied at the temperatures of 18, 21, 24, 27, 30 and 33 degrees C. Thirty eggs of D. hyalinata were exposed to three females of T. atopovirilia for 5h at 25 degrees C and incubated at the different temperatures. The developmental time from egg exposure to adult, parasitism viability, number of adults per parasitized host egg and progeny sex ratio were monitored. The developmental time from egg to adult emergence of the parasitoid exhibited inverse relationship to the temperature, lasting 24.12 days at 18 degrees C and 7.36 days at 33 degrees C. Parasitism viability at 24, 27 and 30 degrees C was higher than 90%. The ratio of T. atapovirilia adult produced per egg and its sex ratio were not affected when using D. hialynata as host. The lowest threshold temperature (Tb) and estimated degree-days over Tb required by T. atopovirilia to develop on eggs of D. hyalinata was 11.99 degrees C and 130.42 masculine C, respectively. Considering the temperature regimes of two areas where cucurbitaces are cultivated in Bahia State (Rio Real and Inhambupe County) it was estimated that T. atopovirilia can achieve more than 32 generation per year. The results suggest that T. atopovirilia has potential to control D. hyalinata eggs with better chance of success under temperature regimes ranging from 24 to 27 degrees C that meets the suitable field conditions for cropping cucurbitaces.

Assigning sex and reproductive stage to adult Lake Sturgeon using ultrasonography and common morphological measurements

USGS Publications Warehouse

Chiotti, Justin A.; Boase, James C.; Hondorp, Darryl W.; Briggs, Andrew S.

2016-01-01

Sex determination of fish species is difficult to assess when sexual dimorphism and gametes are not apparent. For threatened and endangered fish species, noninvasive techniques are needed when determining sex to minimize stress and the potential for mortality. We evaluated the use of a portable ultrasound unit to determine sex of Lake Sturgeon Acipenser fulvescens in the field. Ultrasound images were collected from 9 yellow-egg (F2, F3), 32 black-egg (F4, F5), and 107 fully developed male (M2) Lake Sturgeon. Two readers accurately assigned sex to 88–96% of fish, but accuracy varied in relation to maturity stage. Black-egg females and fully developed males were correctly identified for 89–100% of the fish sampled, while these two readers identified yellow-egg females only 33% and 67% of the time. Time spent collecting images ranged between 2 and 3 min once the user was comfortable with operating procedures. Discriminant analysis revealed the total length : girth ratio was a strong predictor of sex and maturity, correctly classifying 81% of black-egg females and 97% of the fully developed males. However, yellow-egg females were incorrectly classified on all occasions. This study shows the utility of using ultrasonography and a total length : girth ratio for sex determination of Lake Sturgeon in later reproductive stages around the spawning season.

Comparison of size, terminal fall velocity, and density of bighead carp, silver carp, and grass carp eggs for use in drift modeling

USGS Publications Warehouse

George, Amy E.; Garcia, Tatiana; Chapman, Duane C.

2017-01-01

Invasive Asian carp established in the United States spawn in the turbulent water of rivers, and their eggs and early larvae develop while drifting in the current. The eggs, which are believed to perish if they settle before hatching, are slightly denser than water and are held in suspension by water turbulence. It is possible to use egg drift modeling to assess the capability of a river to support the survival of Asian carp eggs. Detection of spawning and estimation of egg abundance in the drift are typically assessed by ichthyoplankton trawls. Correct sampling design and interpretation of trawl data require knowledge of the vertical distribution of eggs in the drift, which can be accomplished with particle transport models. Data that are required to populate models of egg drift and vertical distribution include physical properties of assessed rivers and information on egg size, density, and terminal fall velocity, but data on these egg characteristics have not been previously available. Physical characteristics of the eggs are presented as a function of postfertilization time. We recorded mean egg diameter and terminal fall velocity for eggs from each Asian carp species during the first 5 h of development and at approximately 12 and 22 h postfertilization. Eggs of all species reached their maximum size before 4 h. Water-hardened eggs of Silver Carp Hypophthalmichthys molitrix and Grass Carp Ctenopharyngodon idella were similarly sized in our trials, and water-hardened eggs of Bighead Carp H. nobilis were the largest. After water hardening, Silver Carp eggs sank slowest, and Bighead Carp eggs sank fastest. For a given species, smaller-diameter eggs generally had faster terminal fall velocities and higher specific gravity than larger eggs. We provide regression models of egg density and diameter for all three species, discuss usage of these data in modeling the drift and dispersion of Asian carp eggs, and discuss implications for egg sampling design.

Geographic divergence in upper thermal limits across insect life stages: does behavior matter?

PubMed

MacLean, Heidi J; Higgins, Jessica K; Buckley, Lauren B; Kingsolver, Joel G

2016-05-01

Insects with complex life cycles vary in size, mobility, and thermal ecology across life stages. We examine how differences in the capacity for thermoregulatory behavior influence geographic differences in physiological heat tolerance among egg and adult Colias butterflies. Colias adults exhibit differences in morphology (wing melanin and thoracic setal length) along spatial gradients, whereas eggs are morphologically indistinguishable. Here we compare Colias eriphyle eggs and adults from two elevations and Colias meadii from a high elevation. Hatching success and egg development time of C. eriphyle eggs did not differ significantly with the elevation of origin. Egg survival declined in response to heat-shock temperatures above 38-40 °C and egg development time was shortest at intermediate heat-shock temperatures of 33-38 °C. Laboratory experiments with adults showed survival in response to heat shock was significantly greater for Colias from higher than from lower elevation sites. Common-garden experiments at the low-elevation field site showed that C. meadii adults initiated heat-avoidance and over-heating behaviors significantly earlier in the day than C. eriphyle. Our study demonstrates the importance of examining thermal tolerances across life stages. Our findings are inconsistent with the hypothesis that thermoregulatory behavior inhibits the geographic divergence of physiological traits in mobile stages, and suggest that sessile stages may evolve similar heat tolerances in different environments due to microclimatic variability or evolutionary constraints.

Duplex quantitative real-time PCR assay for the detection and discrimination of the eggs of Toxocara canis and Toxocara cati (Nematoda, Ascaridoidea) in soil and fecal samples.

PubMed

Durant, Jean-Francois; Irenge, Leonid M; Fogt-Wyrwas, Renata; Dumont, Catherine; Doucet, Jean-Pierre; Mignon, Bernard; Losson, Bertrand; Gala, Jean-Luc

2012-12-07

Toxocarosis is a zoonotic disease caused by Toxocara canis (T. canis) and/or Toxocara cati (T. cati), two worldwide distributed roundworms which are parasites of canids and felids, respectively. Infections of humans occur through ingestion of embryonated eggs of T. canis or T. cati, when playing with soils contaminated with dogs or cats feces. Accordingly, the assessment of potential contamination of these areas with these roundworms eggs is paramount. A duplex quantitative real-time PCR (2qPCR) targeting the ribosomal RNA gene internal transcribed spacer (ITS2) has been developed and used for rapid and specific identification of T. canis and T. cati eggs in fecal and soil samples. The assay was set up on DNA samples extracted from 53 adult worms including T. canis, T. cati, T. leonina, Ascaris suum (A. suum) and Parascaris equorum (P. equorum). The assay was used to assess the presence of T. cati eggs in several samples, including 12 clean soil samples spiked with eggs of either T. cati or A. suum, 10 actual soil samples randomly collected from playgrounds in Brussels, and fecal samples from cats, dogs, and other animals. 2qPCR results on dogs and cats fecal samples were compared with results from microscopic examination. 2qPCR assay allowed specific detection of T. canis and T. cati, whether adult worms, eggs spiked in soil or fecal samples. The 2qPCR limit of detection (LOD) in spiked soil samples was 2 eggs per g of soil for a turnaround time of 3 hours. A perfect concordance was observed between 2qPCR assay and microscopic examination on dogs and cats feces. The newly developed 2qPCR assay can be useful for high throughput prospective or retrospective detection of T.canis and/or T. cati eggs in fecal samples as well as in soil samples from playgrounds, parks and sandpits.

Computer vision system for egg volume prediction using backpropagation neural network

NASA Astrophysics Data System (ADS)

Siswantoro, J.; Hilman, M. Y.; Widiasri, M.

2017-11-01

Volume is one of considered aspects in egg sorting process. A rapid and accurate volume measurement method is needed to develop an egg sorting system. Computer vision system (CVS) provides a promising solution for volume measurement problem. Artificial neural network (ANN) has been used to predict the volume of egg in several CVSs. However, volume prediction from ANN could have less accuracy due to inappropriate input features or inappropriate ANN structure. This paper proposes a CVS for predicting the volume of egg using ANN. The CVS acquired an image of egg from top view and then processed the image to extract its 1D and 2 D size features. The features were used as input for ANN in predicting the volume of egg. The experiment results show that the proposed CSV can predict the volume of egg with a good accuracy and less computation time.

Embryo Development inside Female Salamander (Ambystoma jeffersonianum-laterale) Prior to Egg Laying

PubMed Central

Charney, Noah D.; Castorino, John J.; Dobro, Megan J.; Steely, Sarah L.

2014-01-01

The length of embryo retention prior to oviposition is a critical evolutionary trait. In all oviparous salamanders, which include the vast majority of species in the order, fertilization is thought to occur at the time of egg laying. Embryos then enter the first cleavage stage several hours after being deposited. This pattern holds for previously studied individuals in the Ambystoma jeffersonianum-laterale complex. Here, we document an instance in which a female Ambystoma jeffersonianum-laterale was carrying embryos internally that had already reached stage 10 of development. Development likely began several days prior to the start of migration to the breeding pond. This is the first such record for any egg-laying salamander, and suggests a degree of plasticity in the timing of fertilization and development not previously recognized. Further work is needed to ascertain the prevalence, mechanics, and evolutionary significance of this phenomenon. PMID:24651275

A real-time PCR approach to detect predation on anchovy and sardine early life stages

NASA Astrophysics Data System (ADS)

Cuende, Elsa; Mendibil, Iñaki; Bachiller, Eneko; Álvarez, Paula; Cotano, Unai; Rodriguez-Ezpeleta, Naiara

2017-12-01

Recruitment of sardine (Sardina pilchardus Walbaum, 1792) and anchovy (Engraulis encrasicolus Linnaeus, 1758) is thought to be regulated by predation of their eggs and larvae. Predators of sardine and anchovy can be identified by visual taxonomic identification of stomach contents, but this method is time consuming, tedious and may underestimate predation, especially in small predators such as fish larvae. Alternatively, genetic tools may offer a more cost-effective and accurate alternative. Here, we have developed a multiplex real-time polymerase chain reaction (RT-PCR) assay based on TaqMan probes to simultaneously detect sardine and anchovy remains in gut contents of potential predators. The assay combines previously described and newly generated species-specific primers and probes for anchovy and sardine detection respectively, and allows the detection of 0,001 ng of target DNA (which corresponds to about one hundredth of the total DNA present in a single egg). We applied the method to candidate anchovy and sardine egg predators in the Bay of Biscay, Atlantic Mackerel (Scomber scombrus) larvae. Egg predation observed was limited primarily to those stations where sardine and/or anchovy eggs were present. Our developed assay offers a suitable tool to understand the effects of predation on the survival of anchovy and sardine early life stages.

Temperature Requirements of Some Common Forensically Important Blow and Flesh Flies (Diptera) under Laboratory Conditions

PubMed Central

Shiravi, AH; Mostafavi, R; Akbarzadeh, K; Oshaghi, MA

2011-01-01

Background: The aim of his study was to determine development time and thermal requirements of three myiasis flies including Chrysomya albiceps, Lucilia sericata, and Sarcophaga sp. Methods: Rate of development (ROD) and accumulated degree day (ADD) of three important forensic flies in Iran, Chrysomya albiceps, Lucilia sericata, and Sarcophaga sp. by rearing individuals under a single constant temperature (28° C) was calculated using specific formula for four developmental events including egg hatching, larval stages, pupation, and eclosion. Results: Rates of development decreased step by step as the flies grew from egg to larvae and then to adult stage; however, this rate was bigger for blowflies (C. albiceps and L. sericata) in comparison with the flesh fly Sarcophaga sp. Egg hatching, larval stages, and pupation took about one fourth and half of the time of the total pre-adult development time for all of the three species. In general, the flesh fly Sarcophaga sp. required more heat for development than the blowflies. The thermal constants (K) were 130–195, 148–222, and 221–323 degree-days (DD) for egg hatching to adult stages of C. albiceps, L. sericata, and Sarcophaga sp., respectively. Conclusion: This is the first report on thermal requirement of three forensic flies in Iran. The data of this study provide preliminary information for forensic entomologist to establish PMI in the area of study. PMID:22808410

Genetic selection increases parthenogenesis in Chinese painted quail (Coturnix chinensis).

PubMed

Parker, H M; Kiess, A S; Wells, J B; Young, K M; Rowe, D; McDaniel, C D

2010-07-01

Parthenogenesis, embryonic development of an unfertilized egg, occurs naturally in turkey, chicken, and quail species. In fact, parthenogenesis in turkeys and chickens can be increased by genetic selection. However, it is unknown if genetic selection for parthenogenesis is effective in quail or if selection for parthenogenesis affects egg production. Therefore, the objectives of this study were to determine if the incidence of parthenogenesis in quail could be increased by genetic selection and if selection for this trait affects egg production. To prevent fertilization, 1,090 females were caged separately from males at 4 wk of age and then caged individually at 6 wk of age to monitor egg production. Eggs were collected daily, labeled, and stored for 0 to 3 d. After 10 d of incubation, 20 unfertilized eggs from each hen were examined for the occurrence of parthenogenesis and embryonic growth. In the parent (P) generation and subsequent generations (1 to 4), hens laying eggs containing parthenogenetic development and males whose sisters or mothers exhibited parthenogenesis were used for breeding. There was a linear increase in the percentage of hens exhibiting parthenogenesis as generation of selection increased. With each successive generation, there was a quadratic response in the percentage of eggs positive for parthenogenesis. When compared with the P generation, parthenogenesis was almost 3 times greater for eggs laid by the fourth generation (4.6 to 12.5%, respectively). Even when only hens exhibiting parthenogenesis were examined, the percentage of eggs demonstrating embryonic development responded quadratically with generation of selection. The embryonic size at 10 d of incubation was greater for each subsequent generation when compared with the P generation. There was a linear decrease in both egg production and the average position of an egg in a clutch as generation of selection increased. In conclusion, genetic selection for parthenogenesis increased the incidence of parthenogenesis and embryonic size but decreased egg production and average position of an egg in a clutch as generations of selection increased.

Flotation of Toxocara canis Eggs in Commercial Bleach and Effects of Bleach Treatment Times on Larval Development in These Eggs.

PubMed

von Dohlen, Alexa Rosypal; Houk-Miles, Alice E; Zajac, Anne M; Lindsay, David S

2017-04-01

Toxocara canis is a common intestinal nematode of young dogs. Puppies contaminate the environment with large numbers of eggs that can embryonate and become infective in less than a month. Embryonated eggs are infectious for humans and other paratenic hosts. Most T. canis infections in humans are asymptomatic; however, migration of T. canis larvae in the eye and in the central nervous system can result in vision loss, blindness, and even death. The eggs of T. canis are highly resistant to harsh environmental conditions and routinely used chemical disinfectants. The objective of this study was to evaluate the effects of full-strength commercial bleach (5.25% sodium hypochlorite solution) treatment on development of T. canis eggs and to report our serendipitous finding that T. canis eggs in dog feces can float in passive fecal flotation tests using bleach. We also demonstrated that T. canis eggs could be identified using the McMaster's fecal eggs counting test using 100% bleach. Toxocara canis eggs collected from the feces of naturally infected 4-8 wk old puppies were treated with full-strength bleach (5.25% sodium hypochlorite solution) for 15 min, 30 min, 60 min, and 120 min; washed free of bleach smell by centrifugation; and resuspended in 0.1 N sulfuric acid solution to undergo larval development at room temperature for 18 days after exposure to bleach. Motile larvae were observed in T. canis eggs in all groups treated for 15-120 min and eggs continuously exposed to bleach for 18 days. Our results indicate that bleach may not be an appropriate disinfectant for dog kennels, cages, or laboratory utensils and work surfaces. Toxocara canis eggs are resistant to bleach treatment and continue to pose a risk for canine and human infections. Further study is needed to find the most appropriate methods for disinfection and removal of eggs to reduce the risk of transmission of this parasite.

Egg incubation position affects toxicity of air cell administered PCB 126 (3,3?4,4?,5- pentachlorobiphenyl) in chicken (Gallus domesticus) embryos

USGS Publications Warehouse

McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

2007-01-01

The avian egg is used extensively for chemical screening and determining the relative sensitivity of species to environmental contaminants (e.g., metals, pesticides, polyhalogenated compounds). The effect of egg incubation position on embryonic survival, pipping, and hatching success was examined following air cell administration of polychlorinated biphenyl (PCB) congener 126 (3,3',4,4',5-pentachlorobiphenyl [PCB 126]; 500?2,000 pg/g egg) on day 4 of development in fertile chicken (Gallus gallus) eggs. Depending on dose, toxicity was found to be up to nine times greater in vertically versus horizontally incubated eggs. This may be due to enhanced embryonic exposure to the injection bolus in vertically incubated eggs compared to more gradual uptake in horizontally incubated eggs. Following air cell administration of PCB 126, horizontal incubation of eggs may more closely approximate uptake and toxicity that has been observed with naturally incorporated contaminants. These data have implications for chemical screening and use of laboratory data for ecological risk assessments.

A simplified method for correcting contaminant concentrations in eggs for moisture loss.

USGS Publications Warehouse

Heinz, Gary H.; Stebbins, Katherine R.; Klimstra, Jon D.; Hoffman, David J.

2009-01-01

We developed a simplified and highly accurate method for correcting contaminant concentrations in eggs for the moisture that is lost from an egg during incubation. To make the correction, one injects water into the air cell of the egg until overflowing. The amount of water injected corrects almost perfectly for the amount of water lost during incubation or when an egg is left in the nest and dehydrates and deteriorates over time. To validate the new method we weighed freshly laid chicken (Gallus gallus) eggs and then incubated sets of fertile and dead eggs for either 12 or 19 d. We then injected water into the air cells of these eggs and verified that the weights after water injection were almost identical to the weights of the eggs when they were fresh. The advantages of the new method are its speed, accuracy, and simplicity: It does not require the calculation of a correction factor that has to be applied to each contaminant residue.

Progressive chorion morphology during egg development in Samia ricini (Donovan).

PubMed

Renthlei, Collin Z; Raghuvarman, Arumugam; Kharbuli, Besterwell; Dey, Sudip

2010-03-01

The egg of Samia ricini (Donovan), is oval or laterally flattened ellipsoid, freshly laid eggs are candid white while the chorion is colorless and semi-transparent. The surface of the chorion is covered with network patterns of polygons and their shapes are common in the whole surface region. The boundaries between polygons made ridges had distinct acropyles at three-cell junctions. The numbers of aeropyles are variable according to their structures both in the lateral flat and marginal regions. During the course of egg development, no significant structural changes were observed in either the polygonal structures or the overall morphology of the egg. However, the size of the aeropyles kept on changing as the egg matures. The aeropyle increases initially upto day-9 of egg development and then decreases as it approach hatching. Lines of weaknesses were not observed at time of hatching or close to it. Hatching process of the newly emerge larvae are through gnawing. The larva eats their way out through the chorion membrane mostly from the anterior region. Egg buster or spine which aid in hatching are not present in the newly emerge larvae.This article was published online on 25 September 2009. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 6 January 2010.

Temperature-dependent development of Aleyrodes proletella (Homoptera: Aleyrodidae) on two cultivars of broccoli under constant temperatures.

PubMed

Alonso, Daniel; Gómez, Ana Azahara; Nombela, Gloria; Muñiz, Mariano

2009-02-01

Laboratory experiments were conducted to estimate developmental rates and nymphal survival of Aleyrodes proletella Linnaeus (Homoptera: Aleyrodidae) on two broccoli Brassica oleracea L. variety italica Plenck cultivars (Marathon and Agripa) at eight constant temperatures (16, 18, 20, 22, 24, 26, 28, and 30 degrees C). The times required to complete development of egg and first instar decreased with increasing temperature, but the developmental times of second, third, fourth instars, all instars, and egg-adult period were greater at 30 degrees C than at 28degrees C. The relationships between developmental rate of A. proletella and temperature were slightly influenced by broccoli cultivar. The optimal temperatures and thermal constant as well as the lower and upper thresholds of development for all immature stages were estimated by fitting the observed developmental rates versus temperature with a nonlinear model and two linear models. For all stages, graphs obtained by plotting the developmental rates against temperature could be described by the modification two of the Logan's model. Overall, developmental times for immature stages and egg-adult periods were similar on both Agripa and Marathon cultivars. The most favorable temperature range for nymphal development seemed to be 28-29 (second and third instars) and 31-33 degrees C (fourth instar). Mean generation times (egg-adult) ranged from 19 d ('Marathon' and 'Agripa') at 28 degrees C to 47 ('Marathon') and 46 d ('Agripa') at 16 degrees C.

Automatic stage identification of Drosophila egg chamber based on DAPI images

PubMed Central

Jia, Dongyu; Xu, Qiuping; Xie, Qian; Mio, Washington; Deng, Wu-Min

2016-01-01

The Drosophila egg chamber, whose development is divided into 14 stages, is a well-established model for developmental biology. However, visual stage determination can be a tedious, subjective and time-consuming task prone to errors. Our study presents an objective, reliable and repeatable automated method for quantifying cell features and classifying egg chamber stages based on DAPI images. The proposed approach is composed of two steps: 1) a feature extraction step and 2) a statistical modeling step. The egg chamber features used are egg chamber size, oocyte size, egg chamber ratio and distribution of follicle cells. Methods for determining the on-site of the polytene stage and centripetal migration are also discussed. The statistical model uses linear and ordinal regression to explore the stage-feature relationships and classify egg chamber stages. Combined with machine learning, our method has great potential to enable discovery of hidden developmental mechanisms. PMID:26732176

Human Eating Behavior: Preferences. Consumption Patterns, and Biorhythms

DTIC Science & Technology

1978-06-01

preferences developed for all egg entrees, both for the frozen omelets as well as canned ham and eggs . We had expected that at least a few foods would...preference. The only increase in hedonic rating evidenced in both experiments was Ham and Eggs . Subjects seem to like it slighly more over time but want...0.2 -0.37 Ham & eggs c. +0.5 +0.15 Apricots b. -0.2 -0.45 c. -0. Fruit cocktail b. -0.3 -0.72 c. -0.1 Peaches a. 0.0 -0.27 b. -0.1 c.-0.1 Peas c. -0.1

Oxygen uptake by embryos and ovigerous females of two intertidal crabs, Heterozius rotundifrons (Belliidae) and Cyclograpsus lavauxi (Grapsidae): scaling and the metabolic costs of reproduction.

PubMed

Taylor, H H; Leelapiyanart, N

2001-03-01

Heterozius rotundifrons and Cyclograpsus lavauxi are crabs of similar size, whose intertidal habitats overlap. They differ in the number and size of their eggs. A 2 g ovigerous H. rotundifrons incubates 675 large yolky eggs (mean single-egg mass 269 microg; egg clutch 9.15 % of mass of female crab; increasing to 435 microg and 13.4 % at hatching). The egg clutch of a 2 g C. lavauxi is larger (15.4 % of crab mass increasing to 18.9 % at hatching) and contains more numerous (28 000), smaller (10.9 microg increasing to 20.3 microg) eggs. The longer development time of the larger eggs (194 days versus 56 days at 15 degrees C) results from a delayed increase in metabolic rate (diapause) and not metabolic scaling. On the basis of the total mass of single eggs, the mass-specific metabolic rates of early embryonic stages of H. rotundifrons (0.72 micromol g(-1 )h(-1) for the blastula stage at 15 degrees C) and C. lavauxi (1.13 micromol g(-1 )h(-1)) were similar to those of the adult female crabs (0.70 micromol g(-1 )h(-1) for H. rotundifrons and 0.91 micromol g(-1 )h(-1) for C. lavauxi) and increased 13- and 10-fold, respectively, by the time of hatching. Thus, early embryonic metabolic rates were much lower than expected from their mass, but the metabolic rates of pre-hatching embryos were consistent with the allometry of juveniles and adults. Possible interpretations of this apparently anomalous scaling of embryonic metabolic rates are discussed. Mass-specific rates of oxygen consumption by ovigerous females (including the eggs) of both species were higher than for non-ovigerous crabs, in water and in air, and increased greatly during the development of the eggs. This difference was attributable mainly to the increasing metabolic rates of the attached embryos, but early ovigerous crabs (blastula stage) of both species also demonstrated a small elevation in metabolic rate by the crab itself, i.e. a metabolic cost of egg-bearing. In contrast, the elevation of the rate of oxygen consumption by late ovigerous females of C. lavauxi was less than predicted from the metabolic rate of eggs in a stirred respirometer. This suggests that, towards the end of development in C. lavauxi, the oxygen supply to the eggs in situ may be diffusion-limited by unstirred layers, an effect not observed for the larger eggs and more open egg clutch of H. rotundifrons. The cost of development, in terms of total oxygen consumption of single eggs, from extrusion to hatching, was 3.34 micromol O2 (approximately 1.5 J) for H. rotundifrons and 0.105 micromol O2 (approximately 0.05 J) for C. lavauxi. This 30-fold ratio approximates the ratios of their initial masses and yolk contents but represents only approximately one-third of the initial energy contents of the eggs.

Effect of temperature on development and reproduction of the carmine spider mite, Tetranychus cinnabarinus (Acari: Tetranychiae), fed on cassava leaves.

PubMed

Zou, Zhiwen; Xi, Jianfei; Liu, Ge; Song, Shuxian; Xin, Tianrong; Xia, Bin

2018-04-01

The effect of five constant temperatures (16, 20, 24, 28 and 32 °C) on the development, survival and reproduction of Tetranychus cinnabarinus (Boisduval) [= Tetranychus urticae Koch (red form)] fed on cassava leaves was examined in the laboratory at 85% relative humidity. Development time of various immature stages decreased with increasing temperature, with total egg-to-adult development time varying from 27.7 to 6.7 days. The lower thermal threshold for development was 10.8 °C and the thermal constant from egg to adult was 142.4 degree-days. Pre- and post-oviposition period and female longevity all decreased as temperature increased. The longest oviposition period was observed at 20 °C with 20.4 days. Under different temperatures, mated females laid, on average, 1.0, 2.9, 4.7, 4.7 and 4.9 eggs per day, respectively. The maximum fecundity (81.5 eggs per female) was at 28 °C and the intrinsic rate of increase (r m ) was highest (0.25) at 32 °C. The results of this study indicate that T. cinnabarinus population could increase rapidly when cassava leaves serve as a food source. At the appropriate temperature T. cinnabarinus could seriously threaten growth of cassava.

Effect of temperature on embryonic development of Melanotaenia boesemani (Allen and Cross, 1982).

PubMed

Radael, Marcella Costa; Cardoso, Leonardo Demier; de Andrade, Dalcio Ricardo; Ferreira, André Veloso; da Cruz Mattos, Douglas; Vidal, Manuel Vazquez

2016-04-01

The present study aimed to provide data on the time required for Melanotaenia boesemani to complete embryonic development, and to investigate the influence that incubation at different temperatures caused in this species. The effects of temperature on the time and hatching rate are presented, as well as information related to embryonic development stages. After fertilization, the eggs were kept in incubators at 23, 26, 29 or 32°C and observed at predetermined times until the moment of hatching. Stages of development were identified and classified according to morphological and physiological characteristics. Oil droplets were visualized inside the eggs as well as filament adhesion present at the chorion. Embryonic development was similar to that observed in other species of the genus Melanotaenia with hatching and faster development in higher temperatures.

Regulative development of Xenopus laevis in microgravity

NASA Technical Reports Server (NTRS)

Black, S.; Larkin, K.; Jacqmotte, N.; Wassersug, R.; Pronych, S.; Souza, K.

1996-01-01

To test whether gravity is required for normal amphibian development, Xenopus leavis females were induced to ovulate aboard the orbiting Space Shuttle. Eggs were fertilized in vitro, and although early embryonic stages showed some abnormalities, the embryos were able to regulate and produce nearly normal larvae. These results demonstrate for the first time that a vertebrate can ovulate in the virtual absence of gravity, and that the eggs can develop to a free-living stage.

Effects of different storage time on hatching results and some egg quality characteristics of rock partridge (A. graeca) (management and production).

PubMed

Günhan, S; Kirikçi, K

2017-06-01

In this research, partridge eggs were stored during zero to 7, 8 to 14, 15 to 21, 22 to 28, 29 to 35 and 36 to 42 d, respectively. The effect of different egg storage periods on egg protein and moisture rates, mineral contents, and some egg quality and hatching characteristics were investigated. The extension of egg storage times didn't affect the external quality features like shell weight, shell thickness, and albumen rate, but it affected the yolk weight, yolk index, albumen index, and Haugh unit (P < 0.05). Yolk weight was increased and yolk index, albumen index, and Haugh unit values were decreased with the extension of storage time. Different storage times of partridge eggs did not have important effects on the protein rates. Protein and humidity rate of the eggs were 14.21 and 67.64%, respectively. There were some elements such as S, P, Na, K, and Ca, but Al, Cd, Co, Mo, and Pb could not be found in the partridge eggs. There is no effect of the storage time on the mineral content of the egg. Storage time had negative effect on fertility and hatchability after 21 d of storage d, but no effect on hatchability of fertile eggs. As this study showed, partridge eggs are resistant to long storage times, as partridge egg proteins can resist degradation in the optimum storage times. To determine egg degradation, the study should be focused on partridge eggshell features, which are responsible for degradation. As a result of this research, partridge eggs can be stored for 21 d under optimum storage conditions without any negative hatchability results. © 2017 Poultry Science Association Inc.

Timing of food introduction and development of food sensitization in a prospective birth cohort.

PubMed

Tran, Maxwell M; Lefebvre, Diana L; Dai, David; Dharma, Christoffer; Subbarao, Padmaja; Lou, Wendy; Azad, Meghan B; Becker, Allan B; Mandhane, Piush J; Turvey, Stuart E; Sears, Malcolm R

2017-08-01

The effect of infant feeding practices on the development of food allergy remains controversial. We examined the relationship between timing and patterns of food introduction and sensitization to foods at age 1 year in the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort study. Nutrition questionnaire data prospectively collected at age 3, 6, 12, 18, and 24 months were used to determine timing of introduction of cow's milk products, egg, and peanut. At age 1 year, infants underwent skin prick testing to cow's milk, egg white, and peanut. Logistic regression models were fitted to assess the impact of timing of food exposures on sensitization outcomes, and latent class analysis was used to study patterns of food introduction within the cohort. Among 2124 children with sufficient data, delaying introduction of cow's milk products, egg, and peanut beyond the first year of life significantly increased the odds of sensitization to that food (cow's milk adjOR 3.69, 95% CI 1.37-9.08; egg adjOR 1.89, 95% CI 1.25-2.80; peanut adjOR 1.76, 95% CI 1.07-3.01). Latent class analysis produced a three-class model: early, usual, and delayed introduction. A pattern of delayed introduction, characterized by avoidance of egg and peanut during the first year of life, increased the odds of sensitization to any of the three tested foods (adjOR 1.78, 95% CI 1.26-2.49). Avoidance of potentially allergenic foods during the first year of life significantly increased the odds of sensitization to the corresponding foods. © 2017 The Authors. Pediatric Allergy and Immunology Published by John Wiley & Sons Ltd.

Hydraulic and water-quality data collection for the investigation of Great Lakes tributaries for Asian carp spawning and egg-transport suitability

USGS Publications Warehouse

Murphy, Elizabeth A.; Jackson, P. Ryan

2013-01-01

While hydraulic data from all four rivers indicated settling of eggs is possible in some locations, all four rivers also exhibited sufficient temperatures, water-quality characteristics, turbulence, and transport times outside of settling zones for successful suspension and development of Asian carp eggs to the hatching stage before the threat of settlement. These observed data indicate that these four Great Lakes tributaries have sufficient hydraulic and water-quality characteristics to support successful spawning and recruitment of Asian carps. The data indicate that with the right temperature and flow conditions, river reaches as short as 25 km may allow Asian carp eggs sufficient time to develop to hatching. Additionally, examining the relation between critical shear velocity and mean velocity, egg settling appears to take place at mean velocities in the range of 15–25 centimeters per second, a much lower value than is generally cited in the literature. A first-order estimate of the minimum transport velocity for Asian carp eggs in a river can be obtained by using mean flow depth and river substrate data, and curves were constructed to show this relation. These findings would expand the number of possible tributaries suitable for Asian carp spawning and contribute to the understanding of how hydraulic and water-quality information can be used to screen additional rivers in the future.

Egg Cannibalism and its Life History Consequences Vary with Life Stage, Sex, and Reproductive Status in Hippodamia convergens (Coleoptera: Coccinellidae).

PubMed

Bayoumy, Mohamed H; Michaud, J P

2015-08-01

Egg cannibalism is common in Coccinellidae, but its biological consequences have not been fully explored. We examined egg cannibalism by neonates, fourth instars, and adults of Hippodamia convergens Guerin-Meneville for effects on development, reproduction, and progeny fitness. We also tested female adults for ability to avoid cannibalizing their own eggs and first-instar larvae, and both sexes for changes in cannibalism propensity following mating, all in the presence of ad libitum food [larvae: eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), adults: Schizaphis graminum (Rondani)]. Cannibalism by neonates reduced developmental time and increased male body size. Cannibalism in the fourth instar accelerated pupation and led to the production of eggs that hatched faster, regardless of which parent cannibalized. However, egg fertility was improved only by maternal cannibalism in the fourth instar. Females recognized their own egg clusters, sometimes added eggs to them, and preferentially cannibalized nonfilial clusters. Most gravid females cannibalized a first-instar larva within 30 min, whether filial or not. Adult egg cannibalism was similar for virgin males and females, but declined after mating in males, and increased in females, although it had no effect on fecundity or fertility. Daughters of cannibal pairs were heavier than those of other mating combinations, but offspring of noncannibal parents had the fastest development. Reproductive females appeared to use egg cannibalism to reduce risk for their own eggs, increasing the number cannibalized with the number laid. Thus, egg cannibalism in coccinellids varies with life stage, sex, and reproductive condition, independent of food availability, and benefits are life stage specific. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Delayed fertilization of anuran amphibian (Xenopus) eggs leads to reduced numbers of primordial germ cells

NASA Technical Reports Server (NTRS)

Wakahara, M.; Neff, A. W.; Malacinski, G. M.

1984-01-01

Several media were tested for the extent to which they promoted high fertilization efficiencies in ovulated, stripped Xenopus eggs. One medium was selected for maintaining eggs in a 'delayed fertilization' (DelF) condition. DelF eggs displayed several unusual characteristics, including shift of the center of gravity, prominent sperm entrance site, and occasional polyspermy. The frequency of normal pattern formation varied according to the length of time eggs were maintained in the DelF condition. Various developmental abnormalities were observed during gastrulation, neurulation, and organogenesis. Most abnormalities appeared, however, to be related to morphogenesis of the endoderm. Primordial germ cell (PGC) development was examined in DelF eggs which displayed normal external morphological features at the swimming tadpole stage. PGC counts were usually normal in short-duration (eg, 5 hr) DelF eggs, but frequently substantially reduced or completely diminished in longer-duration (eg, 25h) tadpoles. Six spawnings were compared and shown to exhibit considerable variability in fertility, morphogenesis, and PGC development. Yolk platelet shifts and developmental parameters were examined in two additional spawnings. The subcortical cytoplasm in which the germ plasm is normally localized appeared to be disrupted in longer duration DelF eggs. That observation may account for low PGC counts in DelF tadpoles.

Termite queens close the sperm gates of eggs to switch from sexual to asexual reproduction.

PubMed

Yashiro, Toshihisa; Matsuura, Kenji

2014-12-02

Males and females are in conflict over genetic transmission in the evolution of parthenogenesis, because it enhances female reproductive output but deprives the males' genetic contribution. For males, any trait that coerces females into sexual reproduction should increase their fitness. However, in the termite Reticulitermes speratus, queens produce their replacements (neotenic queens) parthenogenetically while using normal sexual reproduction to produce other colony members. Here, we show that termite queens produce parthenogenetic offspring in the presence of kings by closing the micropyles (sperm gates; i.e., openings for sperm entry) of their eggs. Our field survey showed that termite eggs show large variation in numbers of micropyles, with some having none. Microsatellite analysis showed that embryos of micropyleless eggs develop parthenogenetically, whereas those of eggs with micropyles are fertilized and develop sexually. Surveys of eggs among queens of different age groups showed that queens begin to lay micropyleless eggs when they are older and thus, need to produce their replacements parthenogenetically. In addition, we found clear seasonality in new neotenic queen differentiation and micropyleless egg production. This micropyle-dependent parthenogenesis is the first identification, to our knowledge, of the mechanism through which females control egg fertilization over time in diploid animals, implying a novel route of the evolution of parthenogenesis in favor of female interests without interference from males.

Chemical contamination of green turtle (Chelonia mydas) eggs in peninsular Malaysia: implications for conservation and public health.

PubMed

van de Merwe, Jason P; Hodge, Mary; Olszowy, Henry A; Whittier, Joan M; Ibrahim, Kamarruddin; Lee, Shing Y

2009-09-01

Persistent organic pollutants (POPs)-such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)-and heavy metals have been reported in sea turtles at various stages of their life cycle. These chemicals can disrupt development and function of wildlife. Furthermore, in areas such as Peninsular Malaysia, where the human consumption of sea turtle eggs is prevalent, egg contamination may also have public health implications. In the present study we investigated conservation and human health risks associated with the chemical contamination of green turtle (Chelonia mydas) eggs in Peninsular Malaysia. Fifty-five C. mydas eggs were collected from markets in Peninsular Malaysia and analyzed for POPs and heavy metals. We conducted screening risk assessments (SRAs) and calculated the percent of acceptable daily intake (ADI) for POPs and metals to assess conservation and human health risks associated with egg contamination. C. mydas eggs were available in 9 of the 33 markets visited. These eggs came from seven nesting areas from as far away as Borneo Malaysia. SRAs indicated a significant risk to embryonic development associated with the observed arsenic concentrations. Furthermore, the concentrations of coplanar PCBs represented 3 300 times the ADI values set by the World Health Organization. The concentrations of POPs and heavy metals reported in C. mydas eggs from markets in Peninsular Malaysia pose considerable risks to sea turtle conservation and human health.

Duplex quantitative real-time PCR assay for the detection and discrimination of the eggs of Toxocara canis and Toxocara cati (Nematoda, Ascaridoidea) in soil and fecal samples

PubMed Central

2012-01-01

Background Toxocarosis is a zoonotic disease caused by Toxocara canis (T. canis) and/or Toxocara cati (T. cati), two worldwide distributed roundworms which are parasites of canids and felids, respectively. Infections of humans occur through ingestion of embryonated eggs of T. canis or T. cati, when playing with soils contaminated with dogs or cats feces. Accordingly, the assessment of potential contamination of these areas with these roundworms eggs is paramount. Methods A duplex quantitative real-time PCR (2qPCR) targeting the ribosomal RNA gene internal transcribed spacer (ITS2) has been developed and used for rapid and specific identification of T. canis and T. cati eggs in fecal and soil samples. The assay was set up on DNA samples extracted from 53 adult worms including T. canis, T. cati, T. leonina, Ascaris suum (A. suum) and Parascaris equorum (P. equorum). The assay was used to assess the presence of T. cati eggs in several samples, including 12 clean soil samples spiked with eggs of either T. cati or A. suum, 10 actual soil samples randomly collected from playgrounds in Brussels, and fecal samples from cats, dogs, and other animals. 2qPCR results on dogs and cats fecal samples were compared with results from microscopic examination. Results 2qPCR assay allowed specific detection of T. canis and T. cati, whether adult worms, eggs spiked in soil or fecal samples. The 2qPCR limit of detection (LOD) in spiked soil samples was 2 eggs per g of soil for a turnaround time of 3 hours. A perfect concordance was observed between 2qPCR assay and microscopic examination on dogs and cats feces. Conclusion The newly developed 2qPCR assay can be useful for high throughput prospective or retrospective detection of T.canis and/or T. cati eggs in fecal samples as well as in soil samples from playgrounds, parks and sandpits. PMID:23216873

Analysis of the low-molecular weight protein profile of egg-white and its changes during early chicken embryological development.

PubMed

Fang, Jun; Ma, Mei H; Qiu, Ning; Wu, Xiao; Jin, Yong G

2012-01-01

Many low-molecular weight (LMW) proteins in egg-white are potentially bioactive, but the mass range and number of these are not yet fully characterized. The aim of the present study was to map the LMW protein profile in egg-white and provide the basis for further understanding of the physiological function of these proteins. For this purpose, six time points (days 0, 1, 2, 3, 4, 5 of incubation) were selected in an attempt to delineate the LMW proteomic profile in egg-white and its changes during early chicken embryological development. Samples were pretreated using gel chromatography techniques prior to analysis by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). Protein search focused on the mass range m/z 1,000 to 8,000. One hundred and fourteen mass signal peaks of LMW proteins ranging from m/z 1,035.88 to 7,112.91 were detected at all six time points. The observed changes in the LMW protein profile during development were highly dynamic. Eighty six novel mass signal peaks of LMW proteins were generated during incubation, the origin of which could be assigned to the high-molecular weight protein fractions.The list of egg-white LMW proteins provided in this paper is by far the most comprehensive and is intended to serve as a starting point for the isolation and functional characterization of interesting LMW proteins which may play a crucial role in early embryo nutrition and immunity.

Parthenogenetic embryos from unfertilized Chinese painted quail eggs alter albumen pH, gases, and ion concentrations during incubation.

PubMed

Santa Rosa, P; Parker, H M; Kiess, A S; McDaniel, C D

2016-01-15

Parthenogenesis is a form of embryonic development that occurs without fertilization. Recently, parthenogenesis has been reported in Chinese painted quail eggs. In Japanese quail, it has been shown that albumen pH of incubated fertile eggs is lower than that of incubated infertile eggs. However, it is unknown if alterations, similar to those in incubated fertile eggs, occur in albumen pH, gases, or ion concentrations from unfertilized eggs exhibiting parthenogenetic development. Therefore, the objective of this study was to determine if any differences in pH, gases, or ion concentrations exist between incubated unfertilized eggs exhibiting parthenogenetic development versus unfertilized eggs with no development over incubation. In this study, eggs were collected daily from Chinese painted quail hens that were separated from males at 4 weeks of age, before sexual maturity. Eggs were stored for 0 to 3 days at 20 °C and incubated at 37.5 °C for 12 days. Eggs were weighed before and after incubation to obtain percentage egg weight loss. After incubation, embryo size and albumen O2, CO2, Ca(2+), Na(+), and Cl(-) concentrations as well as pH were obtained from each incubated egg. Over incubation, albumen from unfertilized eggs exhibiting parthenogenetic development had a lower pH as well as less O2 and Cl(-), yet a higher Ca(2+) and Na(+) concentration as compared with the albumen of unfertilized eggs with no development. Also, eggs exhibiting parthenogenetic development had a higher albumen CO2 concentration as compared with eggs without development. The rate of egg weight loss was much lower in eggs exhibiting parthenogenetic development as compared with eggs without development. Also, as parthenogen size increased, there was a decrease in albumen pH, O2, and Cl(-), yet an increase in CO2 and Ca(2+). In conclusion, it appears that, over incubation, parthenogenetic development from unfertilized eggs alters the composition of albumen as compared with the albumen from unfertilized eggs with no parthenogenetic development. Published by Elsevier Inc.

Variation in annual clutch phenology of desert tortoises (Gopherus morafkai) in the Sonoran Desert of Arizona

USGS Publications Warehouse

Lovich, Jeffrey E.; Averill-Murray, Roy C.; Agha, Mickey; Ennen, Joshua R.; Austin, Meaghan

2017-01-01

The phenology of egg production and oviposition in organisms affects survival and development of neonates and thus, both offspring and maternal fitness. In addition, in organisms with environmental sex determination, clutch phenology can affect hatchling sex ratios with attendant effects on population demography. The rapid rate of contemporary climate change might disrupt reproductive phenologies that evolved to match environmental conditions. To better understand the response of clutch phenology to annual and long-term changes in climate, we studied a population of Sonoran Desert Tortoises (Gopherus morafkai) in Arizona in 1993 and 1997–2005, specifically quantifying three phenophases, including (1) the estimated time of appearance of shelled eggs in females, (2) the estimated time that eggs were last visible in X-radiographs, and (3) the duration of the interval between the first two events. The mean date for appearance of shelled eggs was 6 June, and the mean date they were last visible was 26 June. After controlling for individual female effects, these dates were different among years. The total number of days that eggs were visible across all females within a year differed among years, but the mean duration of time that clutches were visible, after controlling for individual female effects, was similar among years. Three of 18 females exhibited interannual egg retention on 5 occasions from 52 clutches. Although G. morafkai ovulates only one clutch per year, they might oviposit up to two because of interannual egg retention. Most females produced shelled eggs through heat-unit accumulation achieving 8.3 degree days within a 14-d moving average. The ability to vary the timing of egg formation and oviposition might buffer G. morafkai from some of the effects of predicted increases in temperatures, but species-specific information on developmental temperatures and nesting behavior are needed to determine whether or not the species will be able to produce viable clutches of mixed sex ratios in a warmer climate.

A Meta-Analysis of Experiments Linking Incubation Conditions with Subsequent Leg Weakness in Broiler Chickens

PubMed Central

Groves, Peter J.; Muir, Wendy I.

2014-01-01

A series of incubation and broiler growth studies were conducted using one strain of broiler chicken (fast feathering dam line) observing incubation effects on femoral bone ash % at hatch and the ability of the bird to remain standing at 6 weeks of age (Latency-To-Lie). Egg shell temperatures during incubation were consistently recorded. Parsimonious models were developed across eight studies using stepwise multiple linear regression of egg shell temperatures over 3-day periods and both bone ash at hatch and Latency-To-Lie. A model for bone ash at hatch explained 70% of the variation in this factor and revealed an association with lower egg shell temperatures during days 4–6 and 13–15 and higher egg shell temperatures during days 16–18 of incubation. Bone ash at hatch and subsequent Latency-To-Lie were positively correlated (r = 0.57, P<0.05). A model described 66% of the variation Latency-To-Lie showing significant association of the interaction of femoral ash at hatch and lower average egg shell temperatures over the first 15 days of incubation. Lower egg shell temperature in the early to mid incubation process (days 1–15) and higher egg shell temperatures at a later stage (days 16–18) will both tend to delay the hatch time of incubating eggs. Incubation profiles that resulted in later hatching chicks produced birds which could remain standing for a longer time at 6 weeks of age. This supports a contention that the effects of incubation observed in many studies may in fact relate more to earlier hatching and longer sojourn of the hatched chick in the final stage incubator. The implication of these outcomes are that the optimum egg shell temperature during incubation for broiler leg strength development may be lower than that regarded as ideal (37.8°C) for maximum hatchability and chick growth. PMID:25054636

A meta-analysis of experiments linking incubation conditions with subsequent leg weakness in broiler chickens.

PubMed

Groves, Peter J; Muir, Wendy I

2014-01-01

A series of incubation and broiler growth studies were conducted using one strain of broiler chicken (fast feathering dam line) observing incubation effects on femoral bone ash % at hatch and the ability of the bird to remain standing at 6 weeks of age (Latency-To-Lie). Egg shell temperatures during incubation were consistently recorded. Parsimonious models were developed across eight studies using stepwise multiple linear regression of egg shell temperatures over 3-day periods and both bone ash at hatch and Latency-To-Lie. A model for bone ash at hatch explained 70% of the variation in this factor and revealed an association with lower egg shell temperatures during days 4-6 and 13-15 and higher egg shell temperatures during days 16-18 of incubation. Bone ash at hatch and subsequent Latency-To-Lie were positively correlated (r = 0.57, P<0.05). A model described 66% of the variation Latency-To-Lie showing significant association of the interaction of femoral ash at hatch and lower average egg shell temperatures over the first 15 days of incubation. Lower egg shell temperature in the early to mid incubation process (days 1-15) and higher egg shell temperatures at a later stage (days 16-18) will both tend to delay the hatch time of incubating eggs. Incubation profiles that resulted in later hatching chicks produced birds which could remain standing for a longer time at 6 weeks of age. This supports a contention that the effects of incubation observed in many studies may in fact relate more to earlier hatching and longer sojourn of the hatched chick in the final stage incubator. The implication of these outcomes are that the optimum egg shell temperature during incubation for broiler leg strength development may be lower than that regarded as ideal (37.8°C) for maximum hatchability and chick growth.

The plurennial life cycles of the European Tettigoniidae (Insecta: Orthoptera) : 3. The effect of drought and the variable duration of the initial diapause.

PubMed

Ingrisch, Sigfrid

1986-11-01

The effect of drought on embryonic development and on hatching was studied in 13 European Tettigoniidae species. Drought can affect development in three different ways: (1) Embryonic development proceeds slower than if the eggs are in contact with water; (2) it stops (for final diapause) in an earlier embryonic stage; (3) it affects maintenance and termination of the initial embryonic diapause.In many Tettigoniidae species, the initial diapause is prolonged, and may last several years. Without draught stress, between 1 and 7 cold treatments in the laboratory, and with eggs of the Tettigonia-species between 1 and 6 winters in the field were necessary to enable all eggs to complete initial diapause. In Central European species, the number of eggs maintaining initial diapause significantly increased when the eggs had no contact with water at the time when they should recover from diapause. In contrast, termination of initial diapause in Tettigonia caudata from Greece, when the environment became favorable for growth again, was highest in that group of eggs that had lost most water in a preceding period of drought. The importance of the prolonged initial diapause for the survival of unpredictable adverse conditions is discussed.

What ecological factors can affect albumen corticosterone levels in the clutches of seabirds? Timing of breeding, disturbance and laying order in rockhopper penguins (Eudyptes chrysocome chrysocome).

PubMed

Poisbleau, M; Demongin, L; Angelier, F; Dano, S; Lacroix, A; Quillfeldt, P

2009-06-01

Female birds deposit corticosterone into their eggs. Elevated concentrations of this hormone may interfere with the development of their offspring, and mothers should thus regulate corticosterone levels deposited into the eggs adaptively. However, if females are unable to regulate deposition, then the corticosterone concentration in eggs should reflect that in female plasma and should be influenced by stressors to the females. We measured corticosterone levels in the albumen of rockhopper penguins, and assessed their relationship with hatching order, human disturbance and laying date. Rockhopper penguins (Eudyptes chrysocome chrysocome) lay two eggs, of which the second egg (B-egg) is larger and hatches faster than the first egg (A-egg). The chick hatching from the B-egg is also much more likely to survive than its sibling. Albumen corticosterone concentrations were lower in B-eggs. However, as B-eggs contained more albumen than A-eggs, the total corticosterone deposited in the albumen was not significantly different between the two eggs. Daily disturbance by human observers during albumen production did not influence albumen corticosterone levels. Laying date had an effect on total albumen corticosterone through a higher albumen mass. However, we observed a high individual component in the composition of eggs from the same clutch. Thus, more work is required to explore the hypotheses of passive versus active transfer to eggs and to understand the adaptive value of contrary effects on the amount and concentration of corticosterone.

Identification and quantification of pathogenic helminth eggs using a digital image system.

PubMed

Jiménez, B; Maya, C; Velásquez, G; Torner, F; Arambula, F; Barrios, J A; Velasco, M

2016-07-01

A system was developed to identify and quantify up to seven species of helminth eggs (Ascaris lumbricoides -fertile and unfertile eggs-, Trichuris trichiura, Toxocara canis, Taenia saginata, Hymenolepis nana, Hymenolepis diminuta, and Schistosoma mansoni) in wastewater using different image processing tools and pattern recognition algorithms. The system was developed in three stages. Version one was used to explore the viability of the concept of identifying helminth eggs through an image processing system, while versions 2 and 3 were used to improve its efficiency. The system development was based on the analysis of different properties of helminth eggs in order to discriminate them from other objects in samples processed using the conventional United States Environmental Protection Agency (US EPA) technique to quantify helminth eggs. The system was tested, in its three stages, considering two parameters: specificity (capacity to discriminate between species of helminth eggs and other objects) and sensitivity (capacity to correctly classify and identify the different species of helminth eggs). The final version showed a specificity of 99% while the sensitivity varied between 80 and 90%, depending on the total suspended solids content of the wastewater samples. To achieve such values in samples with total suspended solids (TSS) above 150 mg/L, it is recommended to dilute the concentrated sediment just before taking the images under the microscope. The system allows the helminth eggs most commonly found in wastewater to be reliably and uniformly detected and quantified. In addition, it provides the total number of eggs as well as the individual number by species, and for Ascaris lumbricoides it differentiates whether or not the egg is fertile. The system only requires basically trained technicians to prepare the samples, as for visual identification there is no need for highly trained personnel. The time required to analyze each image is less than a minute. This system could be used in central analytical laboratories providing a remote analysis service. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Egg-Independent Influenza Vaccines and Vaccine Candidates

PubMed Central

Manini, Ilaria; Pozzi, Teresa; Rossi, Stefania; Montomoli, Emanuele

2017-01-01

Vaccination remains the principal way to control seasonal infections and is the most effective method of reducing influenza-associated morbidity and mortality. Since the 1940s, the main method of producing influenza vaccines has been an egg-based production process. However, in the event of a pandemic, this method has a significant limitation, as the time lag from strain isolation to final dose formulation and validation is six months. Indeed, production in eggs is a relatively slow process and production yields are both unpredictable and highly variable from strain to strain. In particular, if the next influenza pandemic were to arise from an avian influenza virus, and thus reduce the egg-laying hen population, there would be a shortage of embryonated eggs available for vaccine manufacturing. Although the production of egg-derived vaccines will continue, new technological developments have generated a cell-culture-based influenza vaccine and other more recent platforms, such as synthetic influenza vaccines. PMID:28718786

Application of gamma irradiation on eggs, active and quiescence stages of Tetranychus urticae Koch as a quarantine treatment of cut flowers

NASA Astrophysics Data System (ADS)

Osouli, Sh.; Ziaie, F.; Haddad Irani Nejad, K.; Moghaddam, M.

2013-09-01

Tetranychus urticae Koch (Tetranychidae) is amongst the most serious pests of cut flowers and ornamentals. In this research the effects of gamma irradiation on different biological stages (including quiescent stages) of this pest have been studied. Irradiation at the doses of 250, 250, 200, 250, 200, 350 and 300 Gy causes sterility of females who were able to reach to adult stage from eggs, larva, protochrysalis, protonymph, deutochrysalis, deutonymph and teliochrysalis stages, respectively. The irradiation caused a decrease in percentage of mites entering the adult stage, developed the adult mite's longevity, number of laid eggs per adult female emerged from irradiated immature stages, and finally a retardation of embryonic and post-embryonic development. The sex ratio of the adult mites resulted from irradiated immature stages was biased towards females through increase of dose. The adult mites developed from irradiated two-day old eggs, three-day old eggs, larva, protochrysalis and deutochrysalis at 100, 350, 300, 350 and 350 Gy, respectively, were 100% females. In general the females resulted from irradiated quiescent stages have shown a high sensitivity to characteristics like eggs hatchability percentage and the emerged adult's sex ratio. On the other hand with regard to percentage of immature mites developed to adult stages, longevity of adult males and females, number of eggs laid by females and the time needed to complete their development, teliochrysalis has been the most tolerant stage. Also a 300 Gy dose could cause sterility in females irradiated at deutonymph stage and mated with adult males irradiated before mating and prevent their eggs to be hatched. In conclusion the most tolerance stages of this mite for most of characteristics was generally the most developed ones and a dose of around 300 Gy could be a phytosanitary irradiation treatment for Tetranychus urticae Koch.

Reproductive biology of galatheoid and chirostyloid (Crustacea: Decapoda) squat lobsters from the Gulf of Mexico.

PubMed

Kilgour, Morgan J; Shirley, Thomas C

2014-01-16

Reproductive timing, fecundity, and average egg sizes were examined for galatheoid and chirostyloid squat lobster collections from the Gulf of Mexico. While congeners did not always significantly differ in egg size or timing, each genus had a unique average egg diameter size which may indicate whether the developing embryos will be lecithotrophic or planktotrophic larvae. The eggs of Eumunididae, Galatheidae, and Munididae were more numerous and smaller than the larger and less abundant eggs of Chirostylidae and Munidopsidae. With the exception of members of the Munididae, members of genera within the same family had distinct egg diameters. Ovigerous females were significantly larger than non-ovigerous females in some species (i.e., Uroptychus nitidus, Munida forceps, Galacantha spinosa, Munidopsis abbreviata, M. alaminos, M., erinacea, M. robusta, M. sigsbei, and M. simplex). Munidopsis erinacea and Munida affinis males were significantly larger than females; the reverse was true for Munidopsis robusta and Munidopsis simplex. All other species studied did not have a significant difference between males and females. The spatial and bathymetric ranges for many species are extended in this study from prior reports. Seasonality of reproduction was evident in few species, but this may be a result of limited sample sizes.

Chemical Contamination of Green Turtle (Chelonia mydas) Eggs in Peninsular Malaysia: Implications for Conservation and Public Health

PubMed Central

van de Merwe, Jason P.; Hodge, Mary; Olszowy, Henry A.; Whittier, Joan M.; Ibrahim, Kamarruddin; Lee, Shing Y.

2009-01-01

Background Persistent organic pollutants (POPs)—such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs)—and heavy metals have been reported in sea turtles at various stages of their life cycle. These chemicals can disrupt development and function of wildlife. Furthermore, in areas such as Peninsular Malaysia, where the human consumption of sea turtle eggs is prevalent, egg contamination may also have public health implications. Objective In the present study we investigated conservation and human health risks associated with the chemical contamination of green turtle (Chelonia mydas) eggs in Peninsular Malaysia. Methods Fifty-five C. mydas eggs were collected from markets in Peninsular Malaysia and analyzed for POPs and heavy metals. We conducted screening risk assessments (SRAs) and calculated the percent of acceptable daily intake (ADI) for POPs and metals to assess conservation and human health risks associated with egg contamination. Results C. mydas eggs were available in 9 of the 33 markets visited. These eggs came from seven nesting areas from as far away as Borneo Malaysia. SRAs indicated a significant risk to embryonic development associated with the observed arsenic concentrations. Furthermore, the concentrations of coplanar PCBs represented 3 300 times the ADI values set by the World Health Organization. Conclusions The concentrations of POPs and heavy metals reported in C. mydas eggs from markets in Peninsular Malaysia pose considerable risks to sea turtle conservation and human health. PMID:19750104

DIFFERENCES IN CULTURAL YIELD OF MYCOBACTERIUM TUBERCULOSIS ON MEDIA PREPARED USING COMMERCIAL AND HOUSEHOLD EGGS.

PubMed

Noori, Muhammad Yahya; AJi, Zaheer; Khan, Ghazala; Sharafat, Shaheen; Masroor, Muhammad

2015-01-01

Mycobacterial culture is considered as the gold standard for TB diagnosis. It is performed on egg-based media using commercially available eggs to grow Mycobacteria from clinical samples. These eggs are known to contain high concentration of antibiotics, including fluoroquinolones, given to chicken to prevent early mortality. This study was performed to compare Mycobacterial growth on media prepared from commercial and antibiotic free household eggs. Sputum samples from negative (No bacilli in 100 oil immersion field), scanty (1-9 AFB in 100 fields), 1+ (10-99 bacilli per field), 2+ (1-10 bacilli per field) and 3+ (>10 bacilli per field) were inoculated dually on Ogawa medium prepared from commercial and household eggs. Tubes were inspected every fourth day for the appearance of colonies till 60 days. Data tabulations and statistical analysis (F test for variation and unpaired Student's t test) were performed on Microsoft Excel. One microscopically negative sample showed growth on media prepared from household eggs, while all were negative on that prepared from commercial eggs. There were significant differences in time to culture positivity for samples graded 1+ (p = 0.02), 2+ (p = 0.002) and 3+ (p = 0.0003). Commercial eggs containing antibiotics can be a source of false negativity in cultures especially in microscopically negative samples. This can be of special concern in HIV patients who have high smear negativity. It is therefore important to either develop provision of antibiotic free eggs for media preparation or to develop and validate other laboratory investigations for smear negative TB patients.

Temperature-independent energy expenditure in early development of the African clawed frog Xenopus laevis.

PubMed

Nagano, Yatsuhisa; Ode, Koji L

2014-08-01

The thermal dissipation of activated eggs and embryos undergoing development from cleavage to the tailbud stage of the African clawed frog Xenopus laevis was measured as a function of incubation time at temperatures ranging from T = 288.2 K to 295.2 K, using a high-precision isothermal calorimeter. A23187-mediated activation of mature eggs induced stable periodic thermal oscillations lasting for 8-34 h. The frequency agreed well with the cell cycle frequency of initial cleavages at the identical temperature. In the developing embryo, energy metabolism switches from embryonic to adult features during gastrulation. The thermal dissipation after gastrulation fit well with a single modified Avrami equation, which has been used for modeling crystal-growth. Both the oscillation frequency of the activated egg and the growth rate of the embryo strongly depend on temperature with the same apparent activation energy of approximately 87 kJ mole(-1). This result suggests that early development proceeds as a single biological time, attributable to a single metabolic rate. A temperature-independent growth curve was derived by scaling the thermogram to the biological time, indicating that the amount of energy expenditure during each developmental stage is constant over the optimal temperature range.

An important source of omega-3 fatty acids, vitamins D and E, carotenoids, iodine and selenium: a new natural multi-enriched egg.

PubMed

Bourre, J M; Galea, F

2006-01-01

As natural eggs can contribute significantly to overcoming dietary deficits, we have designed and studied the composition of multiple-enriched eggs (Benefic eggs) whose composition is close to the natural egg. They are obtained by feeding laying hens in the usual way, but using additional autoclaved linseed, minerals, vitamins and lutein to provide the extra components. These eggs have greater nutritional value than standard. Thus 100 g of these eggs contains 6 times more of the omega-3 fatty acid ALA (15% of the French recommended daily allowance (RDA)), 3 times more DHA (100% of RDA), 3 times more vitamin D (30% of RDA), 4 times more folic acid (70% of RDA), 6 times more vitamin E (66% of RDA), 6 times more lutein and zeaxanthine (70% of international recommendation), 2.5 times more iodine (100% RDA), and 4 times more selenium (45% RDA). As the content of omega-6 fatty acids remains unchanged, the omega-6/omega-3 ratio is lower, and thus improved. These eggs contain a little less cholesterol and, like standard eggs, are rich in vitamin B12 (160% of RDA) and vitamin A (25% of RDA), plus vitamin B2 (riboflavin), vitamin B5 (pantothenic acid) and phosphorus. Proteins quality is indeed excellent. These eggs are interesting for everybody, and particularly appropriate for older people. The nutritional value of enriched eggs (similar to the multiple-enriched eggs of this study) has been assessed in animals and in human volunteers in terms of their influence on blood lipids. They improve the blood concentration of omega-3 fatty acids, HDL cholesterol, LDL cholesterol and triglycerides.

A deep learning framework to discern and count microscopic nematode eggs.

PubMed

Akintayo, Adedotun; Tylka, Gregory L; Singh, Asheesh K; Ganapathysubramanian, Baskar; Singh, Arti; Sarkar, Soumik

2018-06-14

In order to identify and control the menace of destructive pests via microscopic image-based identification state-of-the art deep learning architecture is demonstrated on the parasitic worm, the soybean cyst nematode (SCN), Heterodera glycines. Soybean yield loss is negatively correlated with the density of SCN eggs that are present in the soil. While there has been progress in automating extraction of egg-filled cysts and eggs from soil samples counting SCN eggs obtained from soil samples using computer vision techniques has proven to be an extremely difficult challenge. Here we show that a deep learning architecture developed for rare object identification in clutter-filled images can identify and count the SCN eggs. The architecture is trained with expert-labeled data to effectively build a machine learning model for quantifying SCN eggs via microscopic image analysis. We show dramatic improvements in the quantification time of eggs while maintaining human-level accuracy and avoiding inter-rater and intra-rater variabilities. The nematode eggs are correctly identified even in complex, debris-filled images that are often difficult for experts to identify quickly. Our results illustrate the remarkable promise of applying deep learning approaches to phenotyping for pest assessment and management.

Ouabain-sensitive Rb+ uptake in mouse eggs and preimplantation conceptuses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Winkle, L.J.; Campione, A.L.

1991-07-01

The results of histochemical and immunocytochemical studies have been used elsewhere to support the hypothesis that Na+/K(+)-ATPase expression is initiated or increases dramatically in preimplantation mouse conceptuses just before they begin to cavitate. Moreover, localization of the enzyme in the inner membrane of the mural trophoblast is thought to be involved directly in formation and maintenance of the blastocyst cavity. Presumably, Na+/K(+)-ATPase extrudes the cation, Na+, and therefore water into the cavity. The cation transporting activity of the enzyme can be determined by measuring ouabain-sensitive Rb+ uptake by cells. Therefore, we measured Rb+ uptake in mouse eggs and preimplantation conceptusesmore » at various stages of development. 86Rb+ uptake by conceptuses increased linearly with time for at least 60 min in medium containing 0.7 mM total Rb+ plus K+ in the absence or presence of 1.0 mM ouabain, and ouabain inhibited more than 70% of 86Rb+ uptake. The ouabain concentration at 1/2 of maximum inhibition of the ouabain-sensitive component of 86Rb+ uptake was about 10-20 microM in eggs and conceptuses at all stages of preimplantation development. Moreover, ouabain-sensitive Rb+ uptake had a twofold higher Vmax value in blastocysts than in eggs or conceptuses at earlier stages of development (i.e., approximately 173 vs 70-100 fmole.conceptus-1.min-1), although the total cell surface area also was probably about two times greater in blastocysts than in eggs or other conceptuses. Ouabain-sensitive Rb+ transport in eggs and conceptuses may have occurred via a single ouabain-sensitive Rb+ transporter with a Hill coefficient of 1.5-1.8 (Hill plots). When it was assumed that the Hill coefficient had a value of 2.0, however, eggs and conceptuses appeared to contain at least two forms of Na+/K(+)-ATPase activity.« less

Effects of Temperature and Root Leachates on Embryogenic Development and Hatching of Meloidogyne chitwoodi and M. hapla

PubMed Central

Inserra, R. N.; Griffin, G. D.; Sisson, D. V.

1983-01-01

At 20 C the duration of the embryogenic development of Meloiclogyne chitwoodi and M. hapla was about 20 days. At 10 C the embryogenic development was 82-84 days for M. chitwoodi and 95-97 days for M. hapla. The effect of distilled water and root leachates of potato cv. Russet Burbank, tomato cv. Columbian, and wheat cv. Hyslop on the hatching of eggs of the two root-knot nematode species was investigated at 4, 7, 10, 15, 20, and 25 C (± 1 C). Cumulative egg taatch was no greater in root leachates titan in distilled water, but temperature did significantly affect egg hatch (P = 0.05). Less than 1% of the eggs of both nematode species hatched at 4 C. The percent cumulative hatch at 10 C was significantly less (P = 0.05) than at higher temperatures for both nematodes and significantly more (P = 0.05) M. chitwoodi eggs hatched than did M. hapla eggs. At 15 G the percent cumulative hatch of both species was significantly lower (P = 0.05) than that at 20 and 25 C. The percent cumulative egg hatch of two species did not differ at 25 C, but was higher (P = 0.05) at 25 C than at 20 C. At 7 C the emergence of M. chitwoodi juveniles was about seven times (P = 0.01) greater than that of M. hapla in distilled water. PMID:19295777

Forecasting the spatial and seasonal dynamic of Aedes albopictus oviposition activity in Albania and Balkan countries.

PubMed

Tisseuil, Clément; Velo, Enkelejda; Bino, Silvia; Kadriaj, Perparim; Mersini, Kujtim; Shukullari, Ada; Simaku, Artan; Rogozi, Elton; Caputo, Beniamino; Ducheyne, Els; Della Torre, Alessandra; Reiter, Paul; Gilbert, Marius

2018-02-01

The increasing spread of the Asian tiger mosquito, Aedes albopictus, in Europe and US raises public health concern due to the species competence to transmit several exotic human arboviruses, among which dengue, chikungunya and Zika, and urges the development of suitable modeling approach to forecast the spatial and temporal distribution of the mosquito. Here we developed a dynamical species distribution modeling approach forecasting Ae. albopictus eggs abundance at high spatial (0.01 degree WGS84) and temporal (weekly) resolution over 10 Balkan countries, using temperature times series of Modis data products and altitude as input predictors. The model was satisfactorily calibrated and validated over Albania based observed eggs abundance data weekly monitored during three years. For a given week of the year, eggs abundance was mainly predicted by the number of eggs and the mean temperature recorded in the preceding weeks. That is, results are in agreement with the biological cycle of the mosquito, reflecting the effect temperature on eggs spawning, maturation and hatching. The model, seeded by initial egg values derived from a second model, was then used to forecast the spatial and temporal distribution of eggs abundance over the selected Balkan countries, weekly in 2011, 2012 and 2013. The present study is a baseline to develop an easy-handling forecasting model able to provide information useful for promoting active surveillance and possibly prevention of Ae. albopictus colonization in presently non-infested areas in the Balkans as well as in other temperate regions.

Microbial population analysis of broilers in different flock and embryonic ages from GI, yolk and egg wash via Illumina MiSeq and QIIME pipeline (abstract)

USDA-ARS?s Scientific Manuscript database

There are several food-safety issues related to broiler egg production, including the introduction/proliferation of zoonotic pathogens during embryonic gastrointestinal (GI) tract development. Little is known about the overall GI bacterial communities, how they change over time, or how their composi...

Effect of heavy oil on the development of the nervous system of floating and sinking teleost eggs.

PubMed

Irie, Kouta; Kawaguchi, Masahumi; Mizuno, Kaori; Song, Jun-Young; Nakayama, Kei; Kitamura, Shin-Ichi; Murakami, Yasunori

2011-01-01

Heavy oil (HO) on the sea surface penetrates into fish eggs and prevents the normal morphogenesis. To identify the toxicological effects of HO in the context of the egg types, we performed exposure experiments using floating eggs and sinking eggs. In the course of development, HO-exposed embryos of floating eggs showed abnormal morphology, whereas early larva of the sinking eggs had almost normal morphology. However, the developing peripheral nervous system of sinking eggs showed abnormal projections. These findings suggest that HO exposed fishes have problems in the developing neurons, although they have no morphological malformations. Through these observations, we conclude that HO is strongly toxic to floating eggs in the morphogenesis, and also affect the neuron development in both floating and sinking eggs. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of Temperature on Development and Voltinism of Chaetodactylus krombeini (Acari: Chaetodactylidae): Implications for Climate Change Impacts

DOE PAGES

Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian; ...

2016-08-17

Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, weremore » determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. Lastly, the findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed.« less

Effects of Temperature on Development and Voltinism of Chaetodactylus krombeini (Acari: Chaetodactylidae): Implications for Climate Change Impacts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian

Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, weremore » determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. Lastly, the findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed.« less

Effects of Temperature on Development and Voltinism of Chaetodactylus krombeini (Acari: Chaetodactylidae): Implications for Climate Change Impacts

PubMed Central

Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian; Lee, Eungul; Park, Yong-Lak

2016-01-01

Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, were determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. The findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed. *Scientific Article No. 3278 of the West Virginia Agricultural and Forestry Experiment Station, Morgantown, West Virginia PMID:27532151

Remote monitoring of parental incubation conditions in the greater sandhill crane

USGS Publications Warehouse

Gee, G.F.; Hatfield, J.; Howey, P.J.

1995-01-01

To monitor incubation conditions in nests of greater sandhill cranes, a radiotransmitting egg was built using six temperature sensors, a position sensor, and a light sensor. Sensor readings were received, along with time of observations, and stored in a computer. The egg was used to monitor incubation in nests of six pairs of cranes during 1987 and 1988. Ambient temperature was also measured. Analysis of covariance (ANCOVA) was used to relate highest egg temperature, core egg temperature, and lowest egg temperature to ambient temperature, time since the egg was last turned, and time since the beginning of incubation. Ambient temperature had the greatest effect on egg temperature (P 0.0001), followed by the time since the beginning of incubation and time since the egg was last turned. Pair effect, the class variable in the ANCOVA. was also very significant (P < 0.0001). A nine-term Fourier series was used to estimate the average core egg temperature versus time of day and was found to fit the data well (r2 = 0.94). The Fourier series will be used to run a mechanical incubator to simulate natural incubation conditions for cranes.

[A time-lapse cinematographic analysis of ooplasmic movements during the cleavage ofPimpla turionellae L. (Hymenoptera)].

PubMed

Wolf, Rainer; Krause, Gerhard

1971-09-01

In the eggs ofPimpla turionellae, which are characterized by a long germ anlage ("long-germ egg" type), the cleavage nuclei primarily populate the anterior part and only later appear in the posterior of the egg lumen during the intravitelline cleavage. Gastrulation and segmentation also start within this anterior region. Time-lapse motion pictures served to observe and to check quantitatively even slow movements during cleavage and blastogenesis. In motion diagrams made by means of microkymographic technics the flow within the ooplasm along the longer axis of the egg has been timed.Shortly before the first cleavage in thestrictly unfertilized male eggs a short-time"unipolar flow" sets in from a primary initial region at 90% of their length. Thus a pillar of "central plasm" between both of the poles becomes shifted towards the posterior, while its outer coating layer of "marginal-plasm" is displaced forwards by the same distance. In eggs from fertilized females two successive flows of the same "unipolar" type have been observed.At the end of the third cleavage the energids, heretofore loosely grouped together, become distributed within the central plasm to form a "nuclear column". At the same time a fluently pulsatory "bipolar flow" sets in, within asecondary initial region at 80% of the egg length. Comparable to two mirror-image fountains, parts of the central plasm are carried towards the front pole and to the rear pole of the egg, respectively, while the marginal plasm, together with the oolemma, flows in opposite directions at times. With each pulsation the moving areas of the bipolar flow are shifted more and more towards the egg poles. The occurrence of bipolar flow pulsations, amounting to five, is correlated with the nuclear divisions in a still unknown way. In the rhythm of the bipolar flow, the energids become dispersed within the central plasm with a certain spatial lagging.After the bipolar flow has come to a halt, four further cleavages are indicated by faint local pulsations of the ooplasm. The cleavage nuclei move to the egg surface and pole cells become separatedtied off During blastoderm formation another four faint pulsations are observed, especially within the central ooplasm, all of them clearly synchronized with superficial cleavages. Occurring in mitotic waves, these cleavages indicate a third initial region, with the individual position varying between 10 and 28% of the egg length.Furthermore the technics of time-lapse motion pictures permit a local and temporal determination of extravitelline pole space formation, of a ring-shaped contracted region of slightly thickening periplasm within the secondary initial region, and the dislocation of the oosome towards the egg surface, which results from the activity of the posterior fountain during the phase of bipolar flow. Invagination and segmentation of the embryo become distinct within the secondary initial region, thus identifying this region as a differentiation centre.The correlation of plasm flow and nuclear divisions is discussed as well as the correlation of the initial regions to the different patterns of egg architecture in the longgerm egg type. The correlation between bipolar pulsations and the development of the metameric pattern including the function of the oosomal region is also discussed. The ooplasmic movements as known from egg types other thanPimpla are compared to the above observations.

Location and timing of Asian carp spawning in the Lower Missouri River

USGS Publications Warehouse

Deters, Joseph E.; Chapman, Duane C.; McElroy, Brandon

2013-01-01

We sampled for eggs of Asian carps, (bighead carp Hypophthalmichthys nobilis, silver carp H. molitrix, and grass carp Ctenopharyngodon idella) in 12 sites on the Lower Missouri River and in six tributaries from the months of May through July 2005 and May through June 2006 to examine the spatial and temporal dynamics of spawning activity. We categorized eggs into thirty developmental stages, but usually they could not be identified to species. We estimated spawning times and locations based on developmental stage, temperature dependent rate of development and water velocity. Spawning rate was higher in the daytime between 05:00 and 21:00 h than at night. Spawning was not limited to a few sites, as has been reported for the Yangtze River, where these fishes are native, but more eggs were spawned in areas of high sinuosity. We employ a sediment transport model to estimate vertical egg concentration profiles and total egg fluxes during spawning periods on the Missouri River. We did not identify substantial spawning activity within tributaries or at tributary confluences examined in this study.

Roles of calcium and pH in activation of eggs of the medaka fish, Oryzias latipes

PubMed Central

1983-01-01

Unfertilized eggs of the medaka fish (Oryzias latipes) were injected with pH-buffered calcium buffers. Medaka egg activation is accompanied by a transient increase in cytoplasmic free calcium (Gilkey, J. C., L. F. Jaffe, E. B. Ridgway, and G. T. Reynolds, 1978, J. Cell Biol., 76:448-466). The calcium buffer injections demonstrated that (a) the threshold free calcium required to elicit the calcium transient and activate the egg is between 1.7 and 5.1 microM at pH 7.0, well below the 30 microM reached during the transient, and (b) buffers which hold free calcium below threshold prevent activation of the buffered region in subsequently fertilized eggs. Therefore an increase in free calcium is necessary and sufficient to elicit the calcium transient, and the calcium transient is necessary to activate the egg. Further, these results are additional proof that the calcium transient is initiated and propagated through the cytoplasm by a mechanism of calcium- stimulated calcium release. Finally, a normal calcium transient must propagate through the entire cytoplasm to ensure normal development. Unfertilized eggs were injected with pH buffers to produce short-term, localized changes in cytoplasmic pH. The eggs were then fertilized at various times after injection. In other experiments, unfertilized and fertilized eggs were exposed to media containing either NH4Cl or CO2 to produce longer term, global changes in cytoplasmic pH. These treatments neither activated the eggs nor interfered with the normal development of fertilized eggs, suggesting that even if a natural change in cytoplasmic pH is induced by activation, it has no role in medaka egg development. The injected pH buffers altered the rate of propagation of the calcium transient through the cytoplasm, suggesting that the threshold free calcium required to trigger calcium-stimulated calcium release might be pH dependent. The results of injection of pH-buffered calcium buffers support this conjecture: for a tenfold increase in hydrogen ion concentration, free calcium must also be raised tenfold to elicit the calcium transient. PMID:6411737

Laboratory observation on spawning, fecundity and larval development of amphioxus ( Branchiostoma belcheri Tsingtaunese)

NASA Astrophysics Data System (ADS)

Wu, Xian-Han; Zhang, Shi-Cui; Wang, Yong-Yuan; Zhang, Bao-Lu; Qu, Yan-Mei; Jiang, Xin-Ji

1994-12-01

Although amphioxus is widespread in temperate and tropical seas, its population is diminishing because of environmental pollution. To keep the population of this evolutionarily important animal from diminishing, study on its reproduction and development is necessary. The main findings in this study on the spawning and fecundity of the amphioxus reared in laboratory and its larval development are as follows. 1. Water temperature markedly affected the spawning. It spawned only when water temperature reached 21°C. 2. Spawning of the amphioxus in laboratory was markedly extended. Initially, the amphioxus spawned at about 7:00 PM, but spawning time was postponed as spawning days went on. 3. The number of eggs produced by a female ranged from 1400 to 12800, average of 5800. This also represents the fecundity of the amphioxus because it shedded all eggs within the ovary at a time. 4. During the first few months of life of the amphioxus, its growth rate changed seasonally. The growth rate in summer and fall was greater than that in winter. 5. The pelagic larva became a benthic adult after 50 days. 6. The amphioxus reared in laboratory from fertilized eggs could produce fertile eggs and sperms. These findings can be a foundation for measures to address the problem of diminishing amphioxus population.

Effects of salting treatment on the physicochemical properties, textural properties, and microstructures of duck eggs.

PubMed

Xu, Lilan; Zhao, Yan; Xu, Mingsheng; Yao, Yao; Nie, Xuliang; Du, Huaying; Tu, Yong-Gang

2017-01-01

In order to illuminate the forming process of salted egg, the effects of the brine solution with different salt concentrations on the physicochemical properties, textural properties, and microstructures of duck eggs were evaluated using conventional physicochemical property determination methods. The results showed that the moisture contents of both the raw and cooked egg whites and egg yolks, the springiness of the raw egg yolks and cooked egg whites exhibited a decreasing trend with the increase in the salting time and salt concentration. The salt content, oil exudation and the hardness of the raw egg yolks showed a constantly increasing trend. Viscosity of the raw egg whites showed an overall trend in which it first deceased and then increased and decreased again, which was similar to the trend of the hardness of the cooked egg whites and egg yolks. As the salting proceeded, the pH value of the raw and cooked egg whites declined remarkably and then declined slowly, whereas the pH of the raw and cooked egg yolks did not show any noticeable changes. The effect of salting on the pH value varied significantly with the salt concentration in the brine solution. Scanning electron microscopy (SEM) revealed that salted yolks consist of spherical granules and embedded flattened porosities. It was concluded that the treatment of salt induces solidification of yolk, accompanied with higher oil exudation and the development of a gritty texture. Different salt concentrations show certain differences.

Effects of salting treatment on the physicochemical properties, textural properties, and microstructures of duck eggs

PubMed Central

Xu, Lilan; Zhao, Yan; Xu, Mingsheng; Yao, Yao; Nie, Xuliang; Du, Huaying

2017-01-01

In order to illuminate the forming process of salted egg, the effects of the brine solution with different salt concentrations on the physicochemical properties, textural properties, and microstructures of duck eggs were evaluated using conventional physicochemical property determination methods. The results showed that the moisture contents of both the raw and cooked egg whites and egg yolks, the springiness of the raw egg yolks and cooked egg whites exhibited a decreasing trend with the increase in the salting time and salt concentration. The salt content, oil exudation and the hardness of the raw egg yolks showed a constantly increasing trend. Viscosity of the raw egg whites showed an overall trend in which it first deceased and then increased and decreased again, which was similar to the trend of the hardness of the cooked egg whites and egg yolks. As the salting proceeded, the pH value of the raw and cooked egg whites declined remarkably and then declined slowly, whereas the pH of the raw and cooked egg yolks did not show any noticeable changes. The effect of salting on the pH value varied significantly with the salt concentration in the brine solution. Scanning electron microscopy (SEM) revealed that salted yolks consist of spherical granules and embedded flattened porosities. It was concluded that the treatment of salt induces solidification of yolk, accompanied with higher oil exudation and the development of a gritty texture. Different salt concentrations show certain differences. PMID:28797071

Long-life partners or sex friends? Impact of parental pair bond on offspring personality.

PubMed

Le Bot, Océane; Lumineau, Sophie; de Margerie, Emmanuel; Pittet, Florent; Trabalon, Marie; Houdelier, Cécilia

2014-12-01

Previous investigations reported that some traits of parental relationships, including pair-bond duration or mate behavioural compatibility, influence subsequent offspring fitness by acting on their behaviour and growth and thus their early survival. We hypothesized that the development of a pair bond between sexual partners would have a prenatal influence. This study investigated the impact of two pairing managements on the egg characteristics and development of offspring of Japanese quail (Coturnix c. japonica). Thirty males and 30 females were paired either continuously (C; mates together all the time) or non-continuously (NC; pairs met only three times a week for 5 min). Separation-reunion tests evaluated parental pair bond. Egg yolk testosterone and androstenedione levels were evaluated, and the somatic and behavioural development of C and NC chicks was assessed. Our results revealed that members of C pairs were attached to their mates and, although no significant differences in androgen levels could be evidenced between egg sets, a higher proportion of C pairs' eggs were fertilized and their chicks appeared less emotive and more social. Our results revealed that the parental relationship can modulate the behavioural development of their offspring, probably via non-genetic effects, and this could play a major role in the emergence of inter-individual variability. © 2014. Published by The Company of Biologists Ltd.

Characterization of lipids and antioxidant capacity of novel nutraceutical egg products developed with omega-3-rich oils.

PubMed

Kassis, Nissan M; Gigliotti, Joseph C; Beamer, Sarah K; Tou, Janet C; Jaczynski, Jacek

2012-01-15

Cardiovascular disease has had an unquestioned status of the number one cause of death in the US since 1921. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) have cardio-protective benefits. However, egg is typically a poor source of ω-3 PUFAs and, in general, the American diet is low in these cardio-protective fatty acids. Novel, nutritionally enhanced egg products were developed by substituting yolk with ω-3 PUFA-rich flaxseed, menhaden, algae, or krill oil. Experimental egg products matched composition of hen egg (whole egg). The experimental egg products, mixed whole egg, and a liquid egg product (Egg Beaters) were microwave-cooked and compared. Although fat, protein, and moisture contents of experimental egg products matched (P > 0.05) mixed whole egg, experimental egg products had more (P < 0.05) ω-3 PUFAs, lower (P < 0.05) ω-6/ω-3 ratio, and depending on oil added, a higher (P < 0.05) unsaturated/saturated fatty acids ratio compared to mixed whole egg. Triglycerides were the main lipid class in all experimental egg products except those developed with krill oil, which had even more phospholipids than mixed whole egg. Analysis of thiobarbituric acid reactive substances showed that lipid oxidation of experimental egg products was lower (P < 0.05) or similar (P > 0.05) to mixed whole egg, except for experimental egg products with krill oil. However, peroxide value showed that all egg samples had minimal oxidation. Experimental egg products developed with menhaden or flaxseed oil had the highest (P < 0.05) concentration of the antioxidant, ethyoxquin compared to all other egg samples. However, experimental egg products with krill oil likely contained a natural antioxidant, astaxanthin. This study demonstrated an alternative approach to developing novel, nutraceutical egg products. Instead of dietary modification of chicken feed, yolk substitution with ω-3 PUFAs oils resulted in enhancement of ω-3 PUFAs beyond levels possible to achieve by modifying chicken feed. Copyright © 2011 Society of Chemical Industry.

Ovary transcriptome profiling via artificial intelligence reveals a transcriptomic fingerprint predicting egg quality in striped bass, Morone saxatilis.

PubMed

Chapman, Robert W; Reading, Benjamin J; Sullivan, Craig V

2014-01-01

Inherited gene transcripts deposited in oocytes direct early embryonic development in all vertebrates, but transcript profiles indicative of embryo developmental competence have not previously been identified. We employed artificial intelligence to model profiles of maternal ovary gene expression and their relationship to egg quality, evaluated as production of viable mid-blastula stage embryos, in the striped bass (Morone saxatilis), a farmed species with serious egg quality problems. In models developed using artificial neural networks (ANNs) and supervised machine learning, collective changes in the expression of a limited suite of genes (233) representing <2% of the queried ovary transcriptome explained >90% of the eventual variance in embryo survival. Egg quality related to minor changes in gene expression (<0.2-fold), with most individual transcripts making a small contribution (<1%) to the overall prediction of egg quality. These findings indicate that the predictive power of the transcriptome as regards egg quality resides not in levels of individual genes, but rather in the collective, coordinated expression of a suite of transcripts constituting a transcriptomic "fingerprint". Correlation analyses of the corresponding candidate genes indicated that dysfunction of the ubiquitin-26S proteasome, COP9 signalosome, and subsequent control of the cell cycle engenders embryonic developmental incompetence. The affected gene networks are centrally involved in regulation of early development in all vertebrates, including humans. By assessing collective levels of the relevant ovarian transcripts via ANNs we were able, for the first time in any vertebrate, to accurately predict the subsequent embryo developmental potential of eggs from individual females. Our results show that the transcriptomic fingerprint evidencing developmental dysfunction is highly predictive of, and therefore likely to regulate, egg quality, a biologically complex trait crucial to reproductive fitness.

Eggshell structure in Caiman latirostris eggs improves embryo survival during nest inundation.

PubMed

Cedillo-Leal, César; Simoncini, Melina S; Leiva, Pamela M L; Larriera, Alejandro; Lang, Jeffrey W; Piña, Carlos I

2017-05-17

Egg inundation often results in poor hatching success in crocodylians. However, how tolerant eggs are to submergence, and/or how eggshell ultrastructure may affect embryo survival when inundated, are not well understood. In this study, our objective was to determine if embryo survival in Caiman latirostris is affected by eggshell surface roughness, when eggs are submerged under water. Tolerance to inundation was tested early (day 30) versus late (day 60) in development, using eight clutches (four per time treatments), subdivided into four groups: ( N = 9 per clutch per treatment; 9 × 4 = 36 eggs per group). 'Rough' eggshell represented the natural, unmodified eggshell surface structure. 'Smooth' eggshell surface structure was created by mechanically sanding the natural rough surface to remove surface columnar elements and secondary layer features, e.g. irregularities that result in 'roughness'. When inundated by submerging eggs under water for 10 h at day 30, 'smooth' eggshell structure resulted in more than twice as many dead embryos (16 versus 6, smooth versus rough; N = 36), and fewer than half as many healthy embryos (6 versus 13, smooth versus rough, respectively; N = 36). By contrast, at day 60, inundation resulted in very low hatching success, regardless of eggshell surface structure. Only two hatchlings survived the inundation, notably in the untreated group with intact, rough eggshells. Inundation produced a high rate of malformations (58% at day 30), but did not affect hatchling size. Our results indicate that eggshell roughness enhances embryo survival when eggs are inundated early in development, but not late in development. Apparently, the natural surface 'roughness' entraps air bubbles at the eggshell surface during inundation, thereby facilitating gas exchange through the eggshell even when the egg is submerged under water. © 2017 The Author(s).

Ovary Transcriptome Profiling via Artificial Intelligence Reveals a Transcriptomic Fingerprint Predicting Egg Quality in Striped Bass, Morone saxatilis

PubMed Central

2014-01-01

Inherited gene transcripts deposited in oocytes direct early embryonic development in all vertebrates, but transcript profiles indicative of embryo developmental competence have not previously been identified. We employed artificial intelligence to model profiles of maternal ovary gene expression and their relationship to egg quality, evaluated as production of viable mid-blastula stage embryos, in the striped bass (Morone saxatilis), a farmed species with serious egg quality problems. In models developed using artificial neural networks (ANNs) and supervised machine learning, collective changes in the expression of a limited suite of genes (233) representing <2% of the queried ovary transcriptome explained >90% of the eventual variance in embryo survival. Egg quality related to minor changes in gene expression (<0.2-fold), with most individual transcripts making a small contribution (<1%) to the overall prediction of egg quality. These findings indicate that the predictive power of the transcriptome as regards egg quality resides not in levels of individual genes, but rather in the collective, coordinated expression of a suite of transcripts constituting a transcriptomic “fingerprint”. Correlation analyses of the corresponding candidate genes indicated that dysfunction of the ubiquitin-26S proteasome, COP9 signalosome, and subsequent control of the cell cycle engenders embryonic developmental incompetence. The affected gene networks are centrally involved in regulation of early development in all vertebrates, including humans. By assessing collective levels of the relevant ovarian transcripts via ANNs we were able, for the first time in any vertebrate, to accurately predict the subsequent embryo developmental potential of eggs from individual females. Our results show that the transcriptomic fingerprint evidencing developmental dysfunction is highly predictive of, and therefore likely to regulate, egg quality, a biologically complex trait crucial to reproductive fitness. PMID:24820964

Evidence for paternal leakage in hybrid periodical cicadas (Hemiptera: Magicicada spp.).

PubMed

Fontaine, Kathryn M; Cooley, John R; Simon, Chris

2007-09-12

Mitochondrial inheritance is generally assumed to be maternal. However, there is increasing evidence of exceptions to this rule, especially in hybrid crosses. In these cases, mitochondria are also inherited paternally, so "paternal leakage" of mitochondria occurs. It is important to understand these exceptions better, since they potentially complicate or invalidate studies that make use of mitochondrial markers. We surveyed F1 offspring of experimental hybrid crosses of the 17-year periodical cicadas Magicicada septendecim, M. septendecula, and M. cassini for the presence of paternal mitochondrial markers at various times during development (1-day eggs; 3-, 6-, 9-week eggs; 16-month old 1st and 2nd instar nymphs). We found evidence of paternal leakage in both reciprocal hybrid crosses in all of these samples. The relative difficulty of detecting paternal mtDNA in the youngest eggs and ease of detecting leakage in older eggs and in nymphs suggests that paternal mitochondria proliferate as the eggs develop. Our data support recent theoretical predictions that paternal leakage may be more common than previously estimated.

Evidence for Paternal Leakage in Hybrid Periodical Cicadas (Hemiptera: Magicicada spp.)

PubMed Central

Fontaine, Kathryn M.; Cooley, John R.; Simon, Chris

2007-01-01

Mitochondrial inheritance is generally assumed to be maternal. However, there is increasing evidence of exceptions to this rule, especially in hybrid crosses. In these cases, mitochondria are also inherited paternally, so “paternal leakage” of mitochondria occurs. It is important to understand these exceptions better, since they potentially complicate or invalidate studies that make use of mitochondrial markers. We surveyed F1 offspring of experimental hybrid crosses of the 17-year periodical cicadas Magicicada septendecim, M. septendecula, and M. cassini for the presence of paternal mitochondrial markers at various times during development (1-day eggs; 3-, 6-, 9-week eggs; 16-month old 1st and 2nd instar nymphs). We found evidence of paternal leakage in both reciprocal hybrid crosses in all of these samples. The relative difficulty of detecting paternal mtDNA in the youngest eggs and ease of detecting leakage in older eggs and in nymphs suggests that paternal mitochondria proliferate as the eggs develop. Our data support recent theoretical predictions that paternal leakage may be more common than previously estimated. PMID:17849021

Time trends and patterns of reported egg consumption in the U.S. by sociodemographic characteristics

USDA-ARS?s Scientific Manuscript database

Objectives: To 1) describe time trends of the percentage of individuals in the U.S that consume eggs, 2) describe time trends of the daily amount of eggs consumed per day, and 3) examine differences in the amount of eggs consumed per day; overall and by gender, age, income, education, race-ethnicit...

Early intrauterine embryonic development in Khawia sinensis Hsü, 1935 (Cestoda, Caryophyllidea, Lytocestidae), an invasive tapeworm of carp (Cyprinus carpio): an ultrastructural study.

PubMed

Bruňanská, Magdaléna; Mackiewicz, John S; Młocicki, Daniel; Swiderski, Zdzisław; Nebesářová, Jana

2012-02-01

Intrauterine embryonic development in the caryophyllidean tapeworm Khawia sinensis has been investigated using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate for glycogen. Contrary to previous light microscopy findings that reported the release of non-embryonated eggs of K. sinenesis to the external environment, the present study documents various stages of embryonation (ovoviviparity) within the intrauterine eggs of this cestode. At the initial stage of embryonic development, each fertilised oocyte is accompanied by several vitellocytes that become enclosed within the operculate, electrondense shell. Cleavage divisions result in formation of blastomeres (up to about 24 cells) of various sizes. Mitotic divisions and apparent rosette arrangment of the blastomeres, the latter atypical within the Eucestoda, are observed for the first time in the intrauterine eggs of K. sinenesis. The early embryo enclosed within the electrondense shell is surrounded by a thin membraneous layer which in some enlarged regions shows presence of nuclei. Simultaneously to multiplication and differentiation, some of the blastomeres undergo deterioration. A progressive degeneration of the vitellocytes within eggs provides nutritive reserves, including lipids, for the developing embryo. The possible significance of this atypical timing of the intrauterine embryonic development to (1) the ecology of K. sinensis and that of a recent introduction of another invasive tapeworm, the caryophyllidean Atractolytocestus huronensis Anthony, 1958 to Europe; and (2) the affiliation of caryophyllideans with other lower cestodes, are discussed.

Life cycle of lithobiidae - with a discussion of the r-and K-selection theory.

PubMed

Albert, Anke M

1983-02-01

The life cycle of two lithobiid species (Chilopoda: Lithobiidae) Lithobius mutabilis L. Koch and L. curtipes C.L. Koch in an old beech stand in the Solling is described. In addition to a main egg-laying period lithobiids are able to lay eggs continuously throughout the year. The reproductive potential is small, as only one egg is laid over several days. Most juveniles hatch in the spring and over-winter as L3 or L4 larvae. Epimorph development to attainment of sexual maturity takes nearly 2 years. Adult L. mutablilis live a further 2 years or more, adult L. curtipes about 1 year or more. Total life span is about 5-6 years for L. mutabilis and 4-5 years for L. curtipes. Egg development times and instar durations can be very different for different animals. Mortality is relatively high for eggs and small juveniles and low for post larval instars except the very old animals. A method is presented for construction of a survivorship curve from monthly abundance figures. Due to their slow development, late attainment of reproductive period, long reproductive phase, low reproductive potential, long life span, low mortality of post larval instars except very old animals, lithobiids can be regarded as K-strategists or, better, equilibrium species, among the arthropods. It is argued that the theory of r- and K-selection in its general use is not sufficient for a description of the ecological strategies of animals such as Lithobiomorpha. For lithobiids, variability in development time is a very important means of keeping population size at a constant level. The life cycle of the two lithobiid species is compared with ahat of Geophilomorpha and one henicopid species also occurring in the Solling.

Microscopic Examination of Gallbladder Stones Improves Rate of Detection of Clonorchis sinensis Infection

PubMed Central

Ma, Rui-hong; Luo, Xiao-bing; Zheng, Pei-ming; Luo, Zhen-liang; Yang, Liu-qing

2013-01-01

To improve the rate of detection of Clonorchis sinensis infection, we compared different specimens from patients with cholecystolithiasis. Feces, gallbladder bile, and gallbladder stones collected from 179 consecutive patients with cholecystolithiasis underwent microscopic examination, and according to the results, 30 egg-positive and 30 egg-negative fecal, gallbladder bile, and gallbladder stone specimens, respectively, underwent real-time fluorescent PCR. The detection rates of eggs in feces, bile, and gallbladder stones were 30.7%, 44.7%, and 69.8%, respectively, and the differences were statistically significant (P < 0.01). The PCR results confirmed that the eggs in the specimens were C. sinensis eggs. Eggs in the feces were “fresh” and in the gallbladder stones were “old.” Microscopic examination of gallbladder stones may improve the detection rates of C. sinensis infection, which is important for developing individualized treatments to prevent the recurrence of gallbladder stones and to prevent the occurrence of severe liver damage and cholangiocarcinoma. PMID:23698535

Costs of reproduction can explain the correlated evolution of semelparity and egg size: theory and a test with salmon.

PubMed

Kindsvater, Holly K; Braun, Douglas C; Otto, Sarah P; Reynolds, John D

2016-06-01

Species' life history traits, including maturation age, number of reproductive bouts, offspring size and number, reflect adaptations to diverse biotic and abiotic selection pressures. A striking example of divergent life histories is the evolution of either iteroparity (breeding multiple times) or semelparity (breed once and die). We analysed published data on salmonid fishes and found that semelparous species produce larger eggs, that egg size and number increase with salmonid body size among populations and species and that migratory behaviour and parity interact. We developed three hypotheses that might explain the patterns in our data and evaluated them in a stage-structured modelling framework accounting for different growth and survival scenarios. Our models predict the observation of small eggs in iteroparous species when egg size is costly to maternal survival or egg number is constrained. By exploring trait co-variation in salmonids, we generate new hypotheses for the evolution of trade-offs among life history traits. © 2016 John Wiley & Sons Ltd/CNRS.

Egg embryo development detection with hyperspectral imaging

NASA Astrophysics Data System (ADS)

Lawrence, Kurt C.; Smith, Douglas P.; Windham, William R.; Heitschmidt, Gerald W.; Park, Bosoon

2006-10-01

In the U. S. egg industry, anywhere from 130 million to over one billion infertile eggs are incubated each year. Some of these infertile eggs explode in the hatching cabinet and can potentially spread molds or bacteria to all the eggs in the cabinet. A method to detect the embryo development of incubated eggs was developed. Twelve brown-shell hatching eggs from two replicates (n=24) were incubated and imaged to identify embryo development. A hyperspectral imaging system was used to collect transmission images from 420 to 840 nm of brown-shell eggs positioned with the air cell vertical and normal to the camera lens. Raw transmission images from about 400 to 900 nm were collected for every egg on days 0, 1, 2, and 3 of incubation. A total of 96 images were collected and eggs were broken out on day 6 to determine fertility. After breakout, all eggs were found to be fertile. Therefore, this paper presents results for egg embryo development, not fertility. The original hyperspectral data and spectral means for each egg were both used to create embryo development models. With the hyperspectral data range reduced to about 500 to 700 nm, a minimum noise fraction transformation was used, along with a Mahalanobis Distance classification model, to predict development. Days 2 and 3 were all correctly classified (100%), while day 0 and day 1 were classified at 95.8% and 91.7%, respectively. Alternatively, the mean spectra from each egg were used to develop a partial least squares regression (PLSR) model. First, a PLSR model was developed with all eggs and all days. The data were multiplicative scatter corrected, spectrally smoothed, and the wavelength range was reduced to 539 - 770 nm. With a one-out cross validation, all eggs for all days were correctly classified (100%). Second, a PLSR model was developed with data from day 0 and day 3, and the model was validated with data from day 1 and 2. For day 1, 22 of 24 eggs were correctly classified (91.7%) and for day 2, all eggs were correctly classified (100%). Although the results are based on relatively small sample sizes, they are encouraging. However, larger sample sizes, from multiple flocks, will be needed to fully validate and verify these models. Additionally, future experiments must also include non-fertile eggs so the fertile / non-fertile effect can be determined.

Viability and DNA fragmentation of rainbow trout embryos (Oncorhynchus mykiss) obtained from eggs stored at 4 °C.

PubMed

Ubilla, A; Valdebenito, I; Árias, M E; Risopatrón, J

2016-05-01

In vitro storage of salmonid eggs leads to aging of the cells causing a decline in quality and reducing their capacity to develop and produce embryos. The quality of salmonid embryos is assessed by morphologic analyses; however, data on the application of biomarkers to determine the cell viability and DNA integrity of embryos in these species are limited. The aim of this study was to evaluate the effect on embryo development, viability and DNA fragmentation in the embryonic cells of in vitro storage time at 4 °C of rainbow trout (Oncorhynchus mykiss) eggs. The embryos were obtained by IVF from eggs stored for 0 (control), 48, and 96 hours at 4 °C. At 72 hours after fertilization, dechorionated embryos were examined to determine percentages of developed embryos (embryos with normal cell division morphology), viability (LIVE/DEAD sperm viability kit), and DNA integrity (terminal deoxynucleotidyl transferase [TdT] dUTP nick-end labeling assay). The percentage of developing embryos decreased (P < 0.05) with storage time of the eggs (95.10 ± 2.55; 88.14 ± 4.50; 79.99 ± 6.60 for 0, 48, and 96 hours, respectively). Similarly, cell viability decreased (P < 0.05; 96.07 ± 7.15; 80.42 ± 8.55; 77.47 ± 7.88 for 0, 48, and 96 hours, respectively), and an increase (P < 0.05) in DNA fragmentation in the embryos was observed at 96-hour storage. A positive correlation was found between cell DNA fragmentation and storage time (r = 0.8173; P < 0.0001). The results revealed that terminal deoxynucleotidyl transferase [TdT] dUTP nick-end labeling assay technique is reliable mean to assess the state of the DNA in salmonid embryos and that in vitro eggs storage for 96h reduces embryo development and cell DNA integrity. DNA integrity evaluation constitutes a biomarker of the quality of the ova and resulting embryos so as to predict their capacity to produce good-quality embryos in salmonids, particularly under culture conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

A spatial and genetic analysis of Cowbird host selection

USGS Publications Warehouse

Hahn, D.C.; Sedgwick, J.A.; Painter, I.S.; Casna, N.J.; Morrison, Michael L.; Hall, Linnea S.; Robinson, Scott K.; Rothstein, Stephen I.; Hahn, D. Caldwell; Rich, Terrell D.

1999-01-01

Our study of brood parasitism patterns in forest communities revealed the egg-laying frequency and host selection patterns of female cowbirds. By integrating molecular genetics and spatial data, we have the first published estimate on cowbird laying rates in field studies. The 29 females in the study laid only 1-5 eggs each, much lower than previous estimates from captive cowbirds and extrapolations from ovarian development in capture/recapture studies that had suggested that as many as 40 eggs could be laid per individual cowbird. Cowbird females also were shown for the first time to lay significantly more eggs within the home range areas they established rather than outside the home range. No patterns were uncovered for individual females preferentially parasitizing particular host species

Microbiological Spoilage of Eggs and Egg Products

NASA Astrophysics Data System (ADS)

Shebuski, Joseph R.; Freier, Timothy A.

Chicken eggs are the eggs most commonly consumed by humans. The US per capita consumption was 255 eggs in 2005. Approximately 77 billion eggs were produced in the USA in 2005 (American Egg Board, 2005). Of these about 30% were further processed in some manner and the remainder were consumed as whole shell eggs. The greatest increase in production and consumption of eggs, however, is in the developing countries. China is now the number one producer of eggs, with the USA second, and India third. In fact, developing countries currently have >67% of the global egg production share (Clark, 2007). Only a small percentage of eggs are exported because shell eggs are relatively difficult to transport.

Pasteurization of shell eggs using radio frequency heating

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geveke, David J.; Bigley, Andrew B. W.; Brunkhorst, Christopher D.

The USDA-FSIS estimates that pasteurization of all shell eggs in the U.S. would reduce the annual number of illnesses by more than 110,000. However, less than 3% of shell eggs are commercially pasteurized. One of the main reasons for this is that the commercial hot water process requires as much as 60 min to complete. In the present study, a radio frequency (RF) apparatus was constructed, and a two-step process was developed that uses RF energy and hot water, to pasteurize eggs in less than half the time. In order to select an appropriate RF generator, the impedance of shellmore » eggs was measured in the frequency range of 10–70 MHz. The power density within the egg was modeled to prevent potential hotspots. Escherichia coli (ATCC 35218) was inoculated in the yolk to approximately 7.5 log CFU/ml. The combination process first heated the egg in 35.0 °C water for 3.5 min using 60 MHz RF energy. This resulted in the yolk being preferentially heated to 61 °C. Then, the egg was heated for an additional 20 min with 56.7 °C water. This two-step process reduced the population of E. coli by 6.5 log. The total time for the process was 23.5 min. By contrast, processing for 60 min was required to reduce the E. coli by 6.6 log using just hot water. The novel RF pasteurization process presented in this study was considerably faster than the existing commercial process. As a result, this should lead to an increase in the percentage of eggs being pasteurized, as well as a reduction of foodborne illnesses.« less

Pasteurization of shell eggs using radio frequency heating

DOE PAGES

Geveke, David J.; Bigley, Andrew B. W.; Brunkhorst, Christopher D.

2016-08-21

The USDA-FSIS estimates that pasteurization of all shell eggs in the U.S. would reduce the annual number of illnesses by more than 110,000. However, less than 3% of shell eggs are commercially pasteurized. One of the main reasons for this is that the commercial hot water process requires as much as 60 min to complete. In the present study, a radio frequency (RF) apparatus was constructed, and a two-step process was developed that uses RF energy and hot water, to pasteurize eggs in less than half the time. In order to select an appropriate RF generator, the impedance of shellmore » eggs was measured in the frequency range of 10–70 MHz. The power density within the egg was modeled to prevent potential hotspots. Escherichia coli (ATCC 35218) was inoculated in the yolk to approximately 7.5 log CFU/ml. The combination process first heated the egg in 35.0 °C water for 3.5 min using 60 MHz RF energy. This resulted in the yolk being preferentially heated to 61 °C. Then, the egg was heated for an additional 20 min with 56.7 °C water. This two-step process reduced the population of E. coli by 6.5 log. The total time for the process was 23.5 min. By contrast, processing for 60 min was required to reduce the E. coli by 6.6 log using just hot water. The novel RF pasteurization process presented in this study was considerably faster than the existing commercial process. As a result, this should lead to an increase in the percentage of eggs being pasteurized, as well as a reduction of foodborne illnesses.« less

Embryonic development of the cricket Gryllus bimaculatus.

PubMed

Donoughe, Seth; Extavour, Cassandra G

2016-03-01

Extensive research into Drosophila melanogaster embryogenesis has improved our understanding of insect developmental mechanisms. However, Drosophila development is thought to be highly divergent from that of the ancestral insect and arthropod in many respects. We therefore need alternative models for arthopod development that are likely to be more representative of basally-branching clades. The cricket Gryllus bimaculatus is such a model, and currently has the most sophisticated functional genetic toolkit of any hemimetabolous insect. The existing cricket embryonic staging system is fragmentary, and it is based on morphological landmarks that are not easily visible on a live, undissected egg. To address this problem, here we present a complementary set of "egg stages" that serve as a guide for identifying the developmental progress of a cricket embryo from fertilization to hatching, based solely on the external appearance of the egg. These stages were characterized using a combination of brightfield timelapse microscopy, timed brightfield micrographs, confocal microscopy, and measurements of egg dimensions. These egg stages are particularly useful in experiments that involve egg injection (including RNA interference, targeted genome modification, and transgenesis), as injection can alter the speed of development, even in control treatments. We also use 3D reconstructions of fixed embryo preparations to provide a comprehensive description of the morphogenesis and anatomy of the cricket embryo during embryonic rudiment assembly, germ band formation, elongation, segmentation, and appendage formation. Finally, we aggregate and schematize a variety of published developmental gene expression patterns. This work will facilitate further studies on G. bimaculatus development, and serve as a useful point of reference for other studies of wild type and experimentally manipulated insect development in fields from evo-devo to disease vector and pest management. Copyright © 2015 Elsevier Inc. All rights reserved.

Increase in membrane thickness during development compensates for eggshell thinning due to calcium uptake by the embryo in falcons

NASA Astrophysics Data System (ADS)

Castilla, Aurora M.; van Dongen, Stefan; Herrel, Anthony; Francesch, Amadeu; Martínez de Aragón, Juan; Malone, Jim; José Negro, Juan

2010-02-01

We compared membrane thickness of fully developed eggs with those of non-developed eggs in different endangered falcon taxa. To our knowledge, membrane thickness variation during development has never been examined before in falcons or any other wild bird. Yet, the egg membrane constitutes an important protective barrier for the developing embryo. Because eggshell thinning is a general process that occurs during bird development, caused by calcium uptake by the embryo, eggs are expected to be less protected and vulnerable to breakage near the end of development. Thus, egg membranes could play an important protective role in the later stages of development by getting relatively thicker. We used linear mixed models to explore the variation in membrane thickness ( n = 378 eggs) in relation to developmental stage, taxon, female age, mass and identity (73 females), egg-laying sequence (105 clutches) and the study zone. Our results are consistent with the prediction that egg membranes are thicker in fully developed eggs than in non-developed eggs, suggesting that the increase in membrane thickness during development may compensate for eggshell thinning. In addition, our data shown that thicker membranes are associated with larger, heavier and relatively wider eggs, as well as with eggs that had thinner eggshells. Egg-laying sequence, female age and the study zone did not explain the observed variation of membrane thickness in the falcon taxa studied. As we provide quantitative data on membrane thickness variation during development in falcons not subjected to contamination or food limitation (i.e. bred under captive conditions), our data may be used as a reference for studies on eggs from natural populations. Considering the large variation in membrane thickness and the multiple factors affecting on it and its importance in the protection of the embryo, we encourage other researchers to include measurements on membranes in studies exploring eggshell thickness variation.

Biology and life history of Balcha indica, an ectoparasitoid attacking the emerald ash borer, Agrilus planipennis, in North America.

PubMed

Duan, Jian J; Taylor, Philip B; Fuester, Roger W

2011-01-01

Balcha indica Mani and Kaul (Hymenoptera: Eupelmidae) is a solitary ectoparasitoid attacking larvae, prepupae, and pupae of the emerald ash borer, Agrilus planipennis Fairmaire (Hymenoptera: Eupelmidae). Its fecundity, oviposition rate, longevity, and development time were determined in the laboratory under standard rearing conditions (25 ± 2° C, 65 ± 10% relative humidity, and 14:10 L:D). Adults lived a mean of 59 days with a maximum of 117 days. Lifetime adult fecundity averaged 36 eggs with a maximum 94 eggs per female. The egg stage lasted for a maximum of four days with ~ 50% eggs hatched within two days. The development time of the first instars lasted for a maximum of nine days; 50% of the first instars completed their development (i.e., molted to the next instar) within five days. Instars of the intermediate and final stage larvae (after molting of the first instars occurred) could not be distinguished until they reached the pupal stage, and 50% of those larvae pupated ~ 62 days after adult oviposition. Under the standard rearing conditions, 50% of B. indica took ~ 83 days to complete the life cycle (from egg to adult emergence) ranging from 47 to 129 days. These results suggest that B. indica may not have more than two generations in the mid-Atlantic and Midwest regions of United States, where normal growing seasons--with average temperature above 25° C--are normally less than six months (May-October). Because of the long life span and oviposition period of adults, however, B. indica is likely to have overlapping generations.

Utilization of real time PCR for the assessment of egg burden in the organs of Schistosoma japonicum experimentally infected mice.

PubMed

Dang-Trinh, Minh-Anh; Angeles, Jose Ma M; Moendeg, Kharleezelle J; Macalanda, Adrian Miki C; Higuchi, Luna; Oto, Chiho; Kirinoki, Masashi; Chigusa, Yuichi; Kawazu, Shin-Ichiro

2018-06-01

Schistosoma japonicum, causing zoonotic intestinal schistosomiasis, is found in China, the Philippines and parts of Indonesia. Severe disease manifestations are basically due to the deposition of eggs in some vital organs such as the liver, spleen and brain. Traditionally, histopathological microscopic examination of the egg burden was used to evaluate the intensity of infection in the affected organs. However, this technique is laborious, time-consuming and requires trained personnel. In this study, real time PCR targeting the mitochondrial NADH dehydrogenase I gene was used to compare with microscopic examination of tissue sections in evaluating the egg burdens in different affected organs. Livers, spleens and brains of the S. japonicum infected mice after 8 and 18 weeks post-infection (p.i) were harvested and examined. Results showed that there were statistically significant correlations between the egg burden evaluated by tissue section examination, and the Ct values of the real time PCR of livers with heavy egg burden at 8 (r = -0.81) and 18 (r = -0.80) weeks p.i. Furthermore, a correlation (r = -0.56) between the egg burden assessed by the microscopic examination and Ct value of the real time PCR of spleens with moderate egg burden after 18 weeks p.i and not 8 weeks p.i was also observed. Brains with low egg burden showed no schistosome eggs in the microscopic examination, however one sample tested positive by real time PCR. These results suggested that real time PCR is useful in evaluating schistosome egg burden in the organs of the experimentally infected mice model that will give further insights into the pathology of schistosomiasis. Copyright © 2018 Elsevier Inc. All rights reserved.

Crocodilian perivitelline membrane-bound sperm detection.

PubMed

Augustine, Lauren

2017-05-01

Advanced reproductive technologies (ART's) are often employed with various taxa to enhance captive breeding programs and maintain genetic diversity. Perivitelline membrane-bound (PVM-bound) sperm detection has previously been demonstrated in avian and chelonian species as a useful technique for breeding management. In the absence of embryotic development within an egg, this technique can detect the presence of sperm trapped on the oocyte membrane confirming breeding, male reproductive status, and pair compatibility. PVM-bound sperm were successfully detected in three clutches of Cuban crocodile (Crocodylus rhombifer) eggs at the Smithsonian's National Zoological Park (NZP) for the first time in any crocodilian species. PVM-bound sperm were detected in fresh and incubated C. rhombifer eggs, as well as eggs that were developing (banded) and those that were not (not banded). The results of this study showed significant differences in average sperm densities per egg between clutches (p = 0.001). Additionally, there was not a significant difference within clutches between eggs that banded and those that did not band (Clutch A, p = 0.505; Clutch B, p = 0.665; Clutch C, p = 0.266). The results of this study demonstrate the necessity to microscopically examine eggs that do not develop (do not band), to determine if sperm is present, which can help animal managers problem solve reproductive shortcomings. PVM-bound sperm detection could be a useful technique in assessing crocodilian breeding programs, as well as have potential uses in studies assessing sperm storage, artificial insemination, and artificial incubation. This article is a U.S. Government work and is in the public domain in the USA.

Maternal transfer of mercury to songbird eggs.

PubMed

Ackerman, Joshua T; Hartman, C Alex; Herzog, Mark P

2017-11-01

We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6-10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R 2  = 0.97) and tree swallows (R 2  = 0.97) and (2) during mid to late incubation for tree swallows (R 2  = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%-107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15-1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R 2  < 0.01). We provide equations to translate mercury concentrations from maternal blood to eggs (and vice versa), which should facilitate comparisons among studies and help integrate toxicity benchmarks into a common tissue. Published by Elsevier Ltd.

Maternal transfer of mercury to songbird eggs

USGS Publications Warehouse

Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark

2017-01-01

We evaluated the maternal transfer of mercury to eggs in songbirds, determined whether this relationship differed between songbird species, and developed equations for predicting mercury concentrations in eggs from maternal blood. We sampled blood and feathers from 44 house wren (Troglodytes aedon) and 34 tree swallow (Tachycineta bicolor) mothers and collected their full clutches (n = 476 eggs) within 3 days of clutch completion. Additionally, we sampled blood and feathers from 53 tree swallow mothers and randomly collected one egg from their clutches (n = 53 eggs) during mid to late incubation (6–10 days incubated) to evaluate whether the relationship varied with the timing of sampling the mother's blood. Mercury concentrations in eggs were positively correlated with mercury concentrations in maternal blood sampled at (1) the time of clutch completion for both house wrens (R2 = 0.97) and tree swallows (R2 = 0.97) and (2) during mid to late incubation for tree swallows (R2 = 0.71). The relationship between mercury concentrations in eggs and maternal blood did not differ with the stage of incubation when maternal blood was sampled. Importantly, the proportion of mercury transferred from mothers to their eggs decreased substantially with increasing blood mercury concentrations in tree swallows, but increased slightly with increasing blood mercury concentrations in house wrens. Additionally, the proportion of mercury transferred to eggs at the same maternal blood mercury concentration differed between species. Specifically, tree swallow mothers transferred 17%–107% more mercury to their eggs than house wren mothers over the observed mercury concentrations in maternal blood (0.15–1.92 μg/g ww). In contrast, mercury concentrations in eggs were not correlated with those in maternal feathers and, likewise, mercury concentrations in maternal blood were not correlated with those in feathers (all R2 < 0.01). We provide equations to translate mercury concentrations from maternal blood to eggs (and vice versa), which should facilitate comparisons among studies and help integrate toxicity benchmarks into a common tissue.

Spawning Behavior and Egg Development of Aplysia kurodai Inhabiting the Coastal Waters of Jeju Island, Korea

PubMed Central

Lee, Chi-Hoon; Kaang, Bong-Kiun; Lee, Young-Don

2014-01-01

This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm donors) to the animals in front and as females to the animals behind. The fertilized eggs were packaged in capsules that are embedded in jelly to form a cylindrical string called an egg masses. The number of capsule per cm of the egg masses was 55 to 60 capsules and each capsule within the egg masses held 15 to 25 eggs. After spawning, the egg masses were bright yellow or orange in color. This egg masses color not changed until embryos developed into trochophore stage. Thereafter, as embryo developed from trochophore stage to veliger stage the egg masses color became brownish. The fertilized eggs were spherical, with a diameter of approximately 80±1 μm at spawning. At 5 to 6 days after spawning, the embryo developed into trochophore stage and began to rotate within the egg capsule. In the trochophore stage, the precursor of the velum, called the prototroch or prevelum, developed. At 10 days after spawning, the prevelum is transformed into the velum, and the trochophore developed into veliger stage. Between 10 to 15 days after spawning, the veligers broke out of the egg capsule, and hatched as free-swimming larvae. PMID:25949168

Development of space-fertilized eggs and formation of primordial germ cells in the embryos of medaka fish

NASA Astrophysics Data System (ADS)

Ijiri, K.

In the second International Microgravity Laboratory (IML-2) mission in 1994, four small Japanese killifish (Medaka, Oryzias latipes) made a space travel of 15 days aboard a space shuttle. These four adult Medaka fish successfully mated in space for the first time among vertebrate animals. Moreover, the eggs they laid developed normally, at least in their external appearance, hatching as fry (baby fish) in space. Fish mated and laid eggs every day during the first week. Near the end of the mission most of the eggs had a well-developed body with two pigmented eyes. In total, 43 eggs were laid (detected), out of which 8 fry hatched in space, as truly `space-originated' babies. A further 30 fry hatched within 3 days after landing. This is the normal hatching rate, compared with the ground-based data. Among the 8 space-originated fry, four were killed for histological sections, and germ cells at the gonadal region were counted for each fry. Their numbers were in the range of the germ cells of the normal control fry (ground-kept samples). Thus, as embryos developed normally in their external appearance, inside the embryos the formation of primordial germ cells took place normally in space, and their migration to the genital ridges was not hindered by microgravity. The two of the remaining space-originated fry have grown up and been creating their offspring in the laboratory. This proved that the primordial germ cells formed in space were also normal from a functional point of view. The four space-travelled adult fish re-started mating and laying eggs on the 7th day after landing and continued to do so every day afterward. Fertilization rate and hatchability of these eggs were as high as the eggs laid by the laboratory-kept fish. This fact implies that in gametogenesis of adult fish, there are no specific stages of germ cells extremely susceptible to microgravity.

Modeling the inactivation of ascaris eggs as a function of ammonia concentration and temperature.

PubMed

Fidjeland, J; Nordin, A; Pecson, B M; Nelson, K L; Vinnerås, B

2015-10-15

Ammonia sanitization is a promising technology for sanitizing human excreta intended for use as a fertilizer in agriculture. Ascaris eggs are the most persistent pathogens regarding ammonia inactivation and are commonly present in fecal sludge in low- and middle-income countries. In this study, a model for predicting ammonia inactivation of ascaris eggs was developed. Data from four previous studies were compiled and analyzed statistically, and a mathematical model for the treatment time required for inactivation was created. The inactivation rate increased with NH3 activity to the power of 0.7. The required treatment time was found to decrease 10-fold for each 16 °C temperature increase. Dry matter (DM) content and pH had no direct effect on inactivation, but had an indirect effect due to their impact on NH3 activity, which was estimated using the Pitzer approach. An additional model giving an approximation of Pitzer NH3 activity but based on the Emerson approach, DM content and total ammonia (NHTot) was also developed. The treatment time required for different log10 reductions of ascaris egg viability can thus easily be estimated by the model as a function of NH3 activity and temperature. The impact on treatment time by different treatment options can then be theoretically evaluated, promoting improvements of the treatment e.g. by adding urea or alkaline agents, or increasing the temperature by solar heating. Copyright © 2015 Elsevier Ltd. All rights reserved.

Oocyte cryopreservation for donor egg banking.

PubMed

Cobo, Ana; Remohí, José; Chang, Ching-Chien; Nagy, Zsolt Peter

2011-09-01

Oocyte donation is an efficient alternative to using own oocytes in IVF treatment for different indications. Unfortunately, 'traditional' (fresh) egg donations are challenged with inefficiency, difficulties of synchronization, very long waiting periods and lack of quarantine measures. Given the recent improvements in the efficiency of oocyte cryopreservation, it is reasonable to examine if egg donation through oocyte cryopreservation has merits. The objective of the current manuscript is to review existing literature on this topic and to report on the most recent outcomes from two established donor cryobank centres. Reports on egg donation using slow freezing are scarce and though results are encouraging, outcomes are not yet comparable to a fresh egg donation treatment. Vitrification on the other hand appears to provide high survival rates (90%) of donor oocytes and comparable fertilization, embryo development, implantation and pregnancy rates to traditional (fresh) egg donation. Besides the excellent outcomes, the ease of use for both donors and recipients, higher efficiency, lower cost and avoiding the problem of synchronization are all features associated with the benefit of a donor egg cryobank and makes it likely that this approach becomes the future standard of care. Oocyte donation is one of the last resorts in IVF treatment for couples challenged with infertility problems. However, traditional (fresh) egg donation, as it is performed today, is not very efficient, as typically all eggs from one donor are given to only one recipient, it is arduous as it requires an excellent synchronization between the donor and recipient and there are months or years of waiting time. Because of the development of an efficient oocyte cryopreservation technique, it is now possible to cryo-store donor (as well as non-donor) eggs, maintaining their viability and allowing their use whenever there is demand. Therefore, creating a donor oocyte cryobank would carry many advantages. In the present manuscript, the current experience with oocyte donation using cryopreservation technology is reviewed. The outcomes of two recently established donor egg cryobanks at Instituto Valenciano de Infertilidad in Spain and Reproductive Biology Associates in the USA (involving a large number of cases) demonstrate that egg cryo-survival is high and that fertilization, embryo development, implantation and pregnancy rates are similar to those reported after fresh egg donation. It also provides additional advantages of being more efficient, more economical, easier for both donors and recipients and potentially also safer, because eggs can now be quarantined for 6 months (or longer) to retest for infectious diseases in the donors. It is the opinion of the authors, based on several advantages associated with the use of donor egg cryobanking, that in the future there will be fewer traditional egg donations and increasingly more cryo-egg donations. Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Effects of high and low temperatures on development time and mortality of house dust mite eggs.

PubMed

Mahakittikun, Vanna; Boitano, John Joseph; Ninsanit, Prapakorn; Wangapai, Teerapong; Ralukruedej, Kornraphat

2011-12-01

Hatching of Dermatophagoides pteronyssinus eggs was investigated when exposed to temperatures ranging from -70 to +70°C, at varying degrees of humidity (dry and wet heat, direct sunlight) and lengths of time (seven intervals, ranging from 0.5 to 5 h). Exposure to cold was induced using a domestic refrigerator at 4°C, its freezing compartment at -10°C and a deep freezer at -20, -40 and -70°C. For each time interval, there were three slides containing 30 eggs per slide, except for sunlight (five sets of slides). After treatment, all experimental groups were kept on an open work bench for 15 days of observation at ambient room temperature (ca. 22°C) and ca. 75% relative humidity. Control groups with 10 eggs per slide, in triplicate, followed a similar protocol. An egg was considered hatched if an emerging larva was detected from a cracked shell. Results indicated that at 40°C for both dry and wet heat, approximately 80% of all eggs survived. At direct sunlight and dry heat at 50°C, the thermal death point (TDP) occurred at 3 and 5 h, respectively. At 60 and 70°C both wet and dry heat, TDP occurred almost instantaneously. Under cold conditions, only the deep freezer at -70°C was effective in preventing hatching. It may be concluded that exposure to direct sunlight for 3 h, dry/wet heat of 60 and 70°C for a minimum of 30 min, and -70°C prevent egg hatching. This study may have relevance for mite control procedures.

Effect of gametes aging on their activation and fertilizability in zebrafish (Danio rerio).

PubMed

Cardona-Costa, Jose; Pérez-Camps, Mireia; García-Ximénez, Fernando; Espinós, Francisco J

2009-03-01

The zebrafish represents an important model organism for biological research. In this context, in vitro collection and fertilization of zebrafish gametes are basic and widely used techniques for many topical research works. In this work, the fertilization ability and normal embryo development of gold-type zebrafish sperm and eggs were re-evaluated after being stored for different times at 8 degrees C in a modified medium (Hanks' saline supplemented with 1.5 g BSA and 0.1 g ClNa; 320 mOsm, pH 7.4). Results obtained indicated that the temporal limits usually recommended for zebrafish sperm to fertilize fresh eggs (2 h) could be extended for up to 24 h without significant differences compared with fresh sperm. In contrast, the rapid egg aging observed (even less than 1 h) recommends minimizing as far as possible the egg storage time before fertilization. These results suggest a possible strain difference in the fertilization response.

Persistence and inheritance of costs of resistance to imidacloprid in Colorado potato beetle.

PubMed

Baker, Mitchell B; Alyokhin, Andrei; Porter, Adam H; Ferro, David N; Dastur, Shana R; Galal, Nehal

2007-12-01

Reduced fitness among resistant versus susceptible individuals slows resistance evolution and makes it easier to manage. A loss of resistance costs could indicate novel adaptations or mutations contributing to resistance. We measured costs of resistance to imidacloprid in a Massachusetts resistant population compared with a Massachusetts susceptible population in 1999 in terms of fecundity, hatching success, egg development time, and sprint speed. Resistance was additive and seemed to be polygenic with high heritability. The fecundity cost appeared overdominant in 1999, and the hatch rate cost was partly recessive in 1999, but neither was significantly different from dominant or recessive. In 2004, we repeated our measures of resistance costs in Massachusetts in terms of fecundity and hatching success, and we added a new resistant population from Maine. In 2005, we compared development time of Maine resistant and the laboratory susceptible colony eggs. Significant fecundity costs of resistance were found in both population in both 1999 and 2004, and significant egg developmental time costs were found in 1999 and 2005. However, the hatching success costs of resistance were significant in 1999 and not apparent in 2004, suggesting some modification or replacement of the resistance genes in the intervening time.

[Influence of the Concentration of Dissolved Oxygen on Embryonic Development of the Common Toad (Bufo bufo)].

PubMed

Dmitrieva, E V

2015-01-01

Several series of experiments investigating the influence of dissolved oxygen concentrations on the growth rates and mortality in the embryogenesis of the common toad Bufo bufo were carried out. The experiments showed that, when the eggs develop singly, the lack of oxygen does not lead to an increase in mortality by the time of hatching and results only in a change in the dynamics of mortality: mortality occurs at an earlier stage of development than in the conditions of normal access to oxygen. Taking into account the combined effect of the density of eggs and the dissolved oxygen concentration, we increase the accuracy of analysis of the experimental results and improve the interpretation of the results. In the conditions of different initial density of eggs, the impact of the concentration of dissolved oxygen on mortality and rates of development of the common toad embryos is manifested in different ways. At high density, only a small percentage of embryos survives by the time of hatching, and the embryos are significantly behind in their development compared with the individuals that developed in normal oxygen conditions. The lack of oxygen dissolved in the water slows down the development of embryos of the common toad.

Crayfish (Orconectes virilis) predation on zebra mussels (Dreissena polymorpha)

USGS Publications Warehouse

Love, Joy; Savino, Jacqueline F.

1993-01-01

In laboratory studies, we quantified predation rates and handling time of crayfish (Orconectes virilis) on zebra mussels (Dreissena polymorpha) and rainbow trout (Oncorhhynchus mykiss) eggs. In single prey species tests, crayfish ate zebra mussels at similar rates as they ate rainbow trout eggs. When both prey were present, crayfish preferred rainbow trout eggs. Handling time of mussels was about twice that of rainbow trout eggs, and energetic content of mussels was lower. Therefore, net benefit for foraging on rainbow trout eggs was about three times that of foraging on zebra mussels.

Effect of ultrasonic treatment on reduction of Esherichia coli ATCC 25922 and egg quality parameters in experimentally contaminated hens' shell eggs.

PubMed

Sert, Durmus; Aygun, Ali; Torlak, Emrah; Mercan, Emin

2013-09-01

In this study, hen eggs which were experimentally contaminated with Esherichia coli ATCC 25922 were used. Contaminated eggs were washed statically (S5 to S30; 0 kHz) and by ultrasonic waves (U5 to U30; 35 kHz) for given applications of time (5, 15 and 30 min), then the eggs were stored at 22°C for 14 days. Depending on the time of ultrasonic application, a significant increase in egg shell strength (P < 0.01) was recorded. The highest value of the Haugh unit (67.93, 1 day) was observed on the eggs which were washed by ultrasonic waves. Yolk width values of ultrasonic washed eggs diminished. E. coli was completely removed by 30 min of ultrasonic application. During storage E. coli growth was not detected on the eggs which were washed by ultrasonic waves except the eggs in U5 group (2.04 log CFU eggshell⁻¹) on the first day of storage. Depending on the time of ultrasonic application a significant increase in egg quality parameters (shell strength, albumen height, Haugh units, and yolk height) were observed. The application of ultrasound led to a significant reduction in E. coli numbers on egg shells. © 2013 Society of Chemical Industry.

Assessment of Hydraulic Conditions Supporting the Recruitment of Asian Carp in the Illinois Waterway - A Case Study Using Known Spawning Events of 2015

NASA Astrophysics Data System (ADS)

Soong, D. T.; Garcia, T.; Duncker, J.; Zhu, Z.; Butler, S.; Diana, M.; Wahl, D.

2016-12-01

The upstream movement of Asian carp in the Illinois Waterway poses a potential threat to the Great Lakes. If established within the Great Lakes, Asian carp may disrupt the food web and harm the ecosystems of the Great Lakes. Understanding the Asian carp reproduction, including the timing and locations of adult spawning and the transport and dispersal of eggs and larvae, is essential information for managing the Asian carp population in the Illinois Waterway. The Fluvial Egg Drift Simulator (FluEgg) model, a Lagrangian particle tracking model, has been used to study the transport and dispersal of eggs and larvae. The FluEgg model inputs are water temperature and hydraulic properties. At present, field measured or modeled hydraulics from steady-state simulations have been used in FluEgg modeling and the applications have shown useful results for evaluating Asian carp reproduction in the Illinois Waterway. However, there is a need to use data based on more representative time-variable hydraulic conditions from spawning to the time larvae reach the Gas Bladder Inflation Stage (GBI). The GBI stage is critical because that is the stage when the young fish seek nursery habitat. In June 2015, Asian carp spawning was observed at two locations along the Illinois Waterway, one below Starved Rock Lock and Dam near Utica, and the one in the La Grange Pool near Havana, Illinois. This study analyzes how hydraulic modeling can improve the predictability of the FluEgg model. An unsteady HEC-RAS hydraulic model of the Illinois Waterway from Brandon Road Lock and Dam to Grafton, Illinois was used to reproduce the June 2015 flood event. Hydraulic data from HEC-RAS modeling, including predicted spatial and temporal discharge, water depth, and shear velocity; and measured water temperature data were used as input to the FluEgg model. FluEgg simulation results illustrate the downstream drifting of eggs and larvae until reaching the GBI stage. These simulation results can be analyzed, along with habitat maps, to evaluate the possibility of successful recruitment and to identify nursery habitats. This presentation communicates the important connections between hydraulic characteristics, thermal conditions, the development of eggs and larvae of Asian carp, and the likelihood of recruitment success.

Association between Egg Consumption and Metabolic Disease

PubMed Central

Park, Seon-Joo; Jung, Ji-hye; Choi, Sang-Woon; Lee, Hae-Jeung

2018-01-01

Abstract The effect of high egg intake on metabolic syndrome (MetS), a major risk factor for cardiovascular disease (CVD), has not been clearly elucidated. This study was conducted to review the literature related to egg consumption and the risk of metabolic disease as well as to examine the association between high egg intake and MetS in Korean adults. A literature review was conducted using published papers in PubMed and EMBASE through December 2017. We have reviewed 26 articles, which were associated with egg consumption and metabolic diseases, and found that the results were controversial. Therefore, we analyzed data from 23,993 Korean adults aged 19 yrs and older. MetS was defined based on criteria from the Adult Treatment Panel III. Egg consumption of 4-6 times/wk and 1 time/day were significantly associated with reduced prevalence of MetS (Odds ratio (OR)=0.82; 95% Confidence interval (CI)=0.71-0.95 for 4-6 times/wk, OR=0.83; 95% CI=0.69-0.99 for 1 time/day) compared to those who consumed eggs less than once monthly. However, consuming two or more eggs per day was not associated with MetS. As for the components of MetS, an egg intake of once daily decreased the prevalence of abdominal obesity and an intake of 2-7 eggs weekly was shown to prevent a reduction in the high-density lipoprotein cholesterol levels. This study suggests that while consuming eggs 4-7 times weekly is associated with a lower prevalence of MetS, consuming two or more eggs daily is not associated with a reduced risk for MetS. PMID:29805272

The reaction time of organ-forming substance in goldfish EGG and its relationship with mesodermal formation

NASA Astrophysics Data System (ADS)

Zhang, Shicui; Wu, Shangqin

1988-12-01

Fertilized goldfish eggs were dechorionated with a pair of forceps and were cut off along or a little above the equator into animal and vegetative parts at desired stages with a glass needle or ligated into two connected fragments before cleavage with baby hair loop. Some of the ligated eggs were detached by further fastening soon after ligation, and some released later at different stages (2-cell, 16-cell, 128-cell, 512-cell, mid-blastula) to let the organ-forming substance (OFS) enter the blastoderm. The cholinesterase (ChE) in the resulting embryos was assayed. The results are as follows. 1. All the 142 embryos developed from the animal hemispheres cut off or ligated off before cleavage gave rise to hyperblastula in which no ChE activity was observed. 2. All 50 embryos obtained from animal halves isolated at the 8-cell stage produced ChE. 3. Embryos developed from the eggs released before the 512-cell stage formed ChE, but the later the releasing of the hair knots, the smaller the number of ChE-producing embryos. 4. After the 512-cell stage (excluding this stage), neither ChE nor tissue differentiation occurred in the embryos developed from the unfastened eggs though their OFS flow was set free. Since ChE is thought to be a muscle-specific enzyme in the early developmental stage, it is concluded that the OFS in goldfish egg appears to be indispensable for the establishment of the mesoderm.

Factors affecting the toxicity of methylmercury injected into eggs

USGS Publications Warehouse

Heinz, G.H.; Hoffman, D.J.; Kondrad, S.L.; Erwin, C.A.

2006-01-01

We developed a standardized protocol for comparing the sensitivities of the embryos of different bird species to methylmercury when methylmercury was injected into their eggs. During the course of developing this protocol, we investigated the effects of various factors on the toxicity of the injected methylmercury. Most of our experiments were done with chicken (Gallus domesticus), mallard (Anas platyrhynchos), and ring-necked pheasant (Phasianus colchicus) eggs, all of which were purchased in large numbers from game farms. A smaller amount of work was done with double-crested cormorant (Phalacrocorax auritus) eggs collected from the wild. Several solvents were tested, and corn oil at a rate of 1 ??l/g egg contents was selected for the final standardized protocol because it had minimal toxicity to embryos and because methylmercury dissolved in corn oil yielded a dose-response curve in a range of egg concentrations that was similar to the range that causes reproductive impairment when the mother deposits methylmercury into her own eggs. The embryonic stage at which eggs were injected with corn oil altered mercury toxicity; at early stages, the corn oil itself was toxic. Therefore, in the final protocol we standardized the time of injection to occur when each species reached the morphologic equivalent of a 3-day-old chicken embryo. Although solvents can be injected directly into the albumen of an egg, high embryo mortality can occur in the solvent controls because of the formation of air bubbles in the albumen. Our final protocol used corn oil injections into the air cell, which are easier and safer than albumen injections. Most of the methylmercury, when dissolved in corn oil, injected into the air cell passes through the inner shell membrane and into the egg albumen. Most commercial incubators incubate eggs in trays with the air cell end of the egg pointing upward, but we discovered that mercury-induced mortality was too great when eggs were held in this orientation. In addition, some species of bird eggs require incubation on their sides with the eggs being rolled 180?? for them to develop normally. Therefore, we adopted a procedure of incubating the eggs of all species on their sides and rolling them 180?? every hour. Little has been published about the conditions of temperature, humidity, and the movements to which eggs of wild birds need to be subjected for them to hatch optimally under artificial incubation. Not unexpectedly, hatching success in an artificial incubator is generally less than what natural incubation by the parents can achieve. However, the survival of control embryos of most wild bird species was good (generally ??? 80%) up to within 1 or 2 days of hatching when we incubated the eggs at 37.5??C (or 37.6??C for gallinaceous species) at a relative humidity that resulted in an approximate 15% to 16% loss in egg weight by the end of incubation and by incubating the eggs on their sides and rolling them 180??/h. To improve statistical comparisons, we used survival through 90% of incubation as our measurement to compare survival of controls with survival of eggs injected with graded concentrations of mercury. ?? 2006 Springer Science+Business Media, Inc.

Factors affecting the toxicity of methylmercury injected into eggs

USGS Publications Warehouse

Heinz, G.H.; Hoffman, D.J.; Kondrad, S.L.; Erwin, C.A.

2006-01-01

We developed a standardized protocol for comparing the sensitivities of the embryos of different bird species to methylmercury when methylmercury was injected into their eggs. During the course of developing this protocol, we investigated the effects of various factors on the toxicity of the injected methylmercury. Most of our experiments were done with chicken (Gallus domesticus), mallard (Anas platyrhynchos), and ring-necked pheasant (Phasianus colchicus) eggs, all of which were purchased in large numbers from game farms. A smaller amount of work was done with double-crested cormorant (Phalacrocorax auritus) eggs collected from the wild. Several solvents were tested, and corn oil at a rate of 1 :l/g egg contents was selected for the final standardized protocol because it had minimal toxicity to embryos and because methylmercury dissolved in corn oil yielded a dose?response curve in a range of egg concentrations that was similar to the range that causes reproductive impairment when the mother deposits methylmercury into her own eggs. The embryonic stage at which eggs were injected with corn oil altered mercury toxicity; at early stages, the corn oil itself was toxic. Therefore, in the final protocol we standardized the time of injection to occur when each species reached the morphologic equivalent of a 3-day-old chicken embryo. Although solvents can be injected directly into the albumen of an egg, high embryo mortality can occur in the solvent controls because of the formation of air bubbles in the albumen. Our final protocol used corn oil injections into the air cell, which are easier and safer than albumen injections. Most of the methylmercury, when dissolved in corn oil, injected into the air cell passes through the inner shell membrane and into the egg albumen. Most commercial incubators incubate eggs in trays with the air cell end of the egg pointing upward, but we discovered that mercury-induced mortality was too great when eggs were held in this orientation. In addition, some species of bird eggs require incubation on their sides with the eggs being rolled 180? for them to develop normally. Therefore, we adopted a procedure of incubating the eggs of all species on their sides and rolling them 180? every hour. Little has been published about the conditions of temperature, humidity, and the movements to which eggs of wild birds need to be subjected for them to hatch optimally under artificial incubation. Not unexpectedly, hatching success in an artificial incubator is generally less than what natural incubation by the parents can achieve. However, the survival of control embryos of most wild bird species was good (generally > 80%) up to within 1 or 2 days of hatching when we incubated the eggs at 37.5?C (or 37.6?C for gallinaceous species) at a relative humidity that resulted in an approximate 15% to 16% loss in egg weight by the end of incubation and by incubating the eggs on their sides and rolling them 180?/h. To improve statistical comparisons, we used survival through 90% of incubation as our measurement to compare survival of controls with survival of eggs injected with graded concentrations of mercury.

Characterization of egg white antibacterial properties during the first half of incubation: A comparative study between embryonated and unfertilized eggs.

PubMed

Guyot, N; Réhault-Godbert, S; Slugocki, C; Harichaux, G; Labas, V; Helloin, E; Nys, Y

2016-12-01

Egg white is an important contributor to the protection of eggs against bacterial contaminations during the first half of incubation (day zero to 12), prior to the egg white transfer into the amniotic fluid to be orally absorbed by the embryo. This protective system relies on an arsenal of antimicrobial proteins and on intrinsic physicochemical properties that are generally unfavorable for bacterial multiplication and dissemination. Some changes in these parameters can be observed in egg white during egg storage and incubation. The aim of this work was to characterize changes in the antibacterial potential of egg white in embryonated eggs (FE) during the first half of incubation using unfertilized eggs (UF) as controls. Egg white samples were collected at day zero, 4, 8, and 12 and analyzed for pH, protein concentration, and protein profile. Antibacterial properties of egg white proteins were evaluated against Listeria monocytogenes, Streptococcus uberis, Staphylococcus aureus, Escherichia coli, and Salmonella Enteritidis. During incubation, differential variations of egg white pH and protein concentrations were observed between UF and FE. At equal protein concentrations, similar activities against L. monocytogenes and S. uberis were observed for FE and UF egg white proteins. A progressive decline in these activities, however, was observed over incubation time, regardless of the egg group (UF or FE). SDS-PAGE analysis of egg white proteins during incubation revealed discrete changes in the profile of major proteins, whereas the stability of some less abundant antimicrobial proteins seemed more affected. To conclude, the antibacterial activity of egg white proteins progressively decreased during the first half of egg incubation, possibly resulting from the alteration of specific antimicrobial proteins. This apparent decline may be partly counterbalanced in embryonated eggs by the increase in egg white protein concentration. The antibacterial potential of egg white is very effective during early stages of embryonic development but its alteration during incubation suggests that extra-embryonic structures could then progressively ensure protective functions. © 2016 Poultry Science Association Inc.

Incubation media affect the survival, pathway and time of embryo development in Neotropical annual fish Austrolebias nigrofasciatus (Rivulidae).

PubMed

da Fonseca, A P; Volcan, M V; Robaldo, R B

2018-01-01

To analyse the survival, pathway and time of embryo development in the annual fish Austrolebias nigrofasciatus eggs were monitored in four liquid media and two damp media under experimental conditions for 130 days until their development was complete. Eggs kept in the same breeding water from oviposition remained in diapause I (DI) during all experiments. In constrast, up to the stage prior to entering diapause II (DII), the other media had no influence on development. Embryos at this stage (DII), however, show longer development time when treated in medium with water and powdered coconut shell so that about 80% of embryos remained in DII at 100 days. In contrast, all other treatments had a significantly lower proportion of embryos remaining in DII. When treated with Yamamoto's solution in humid media, embryos showed the fastest development. The first fully developed embryos (DIII) were seen at 27 days after oviposition. It took an average of 46-58 days for 50% of eggs in each treatment to reach DIII. Compared with other studies, survival in all incubation media was high at between 70 and 98%. Taken together, it can be concluded that all incubation media were found to be viable for maintaining embryos. Altering developmental trajectories through the manipulation of diapauses in different media makes this species a potential model organism for laboratory studies. © 2017 The Fisheries Society of the British Isles.

Long-lasting and sex-specific consequences of elevated egg yolk testosterone for social behavior in Japanese quail.

PubMed

Schweitzer, Cécile; Goldstein, Michael H; Place, Ned J; Adkins-Regan, Elizabeth

2013-01-01

In birds, early exposure to steroid hormones deposited in egg yolks is hypothesized to result in long-lasting effects on brain and behavior. However, the long-term effects of maternal androgens on the development of social behavior, and whether these could interfere with the effects of the endogenous gonadal hormones that mediate sexual differentiation, remain poorly known. To answer these questions, we enhanced yolk testosterone by injecting testosterone (T) in oil into Japanese quail (Coturnix japonica) eggs prior to incubation. Vehicle-injected (V) eggs served as controls. From age 3 weeks to 8 weeks, sexual development was measured using morphological and physiological traits, and social behavior was measured, including male-typical sexual behavior. In females, treatment with testosterone boosted growth. Males from T-injected eggs developed an affiliative preference for familiar females and differed from V-injected males in the acoustic features of their crows, whereas sexual interest (looking behavior) and copulatory behavior were not affected. These long-lasting and sex-specific yolk testosterone effects on the development of dimorphic traits, but without disrupting sexual differentiation of reproductive behavior suggest potential organizational effects of maternal testosterone, but acting through separate processes than the endocrine mechanisms previously shown to control sexual differentiation. Separate processes could reflect the action of androgens at different times or on multiple targets that are differentially sensitive to steroids or develop at different rates. Copyright © 2012 Elsevier Inc. All rights reserved.

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss)

PubMed Central

Schultz, Irv; Brown, Kim H.; Nagler, James J.

2008-01-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 μg/kg/day BDE-47 and female trout continuously exposed for 60–77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two–three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring. PMID:18397801

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss).

PubMed

Schultz, Irv; Brown, Kim H; Nagler, James J

2008-07-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 microg/kg/day BDE-47 and female trout continuously exposed for 60-77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two-three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring.

Launch Conditions Might Affect the Formation of Blood Vessel in the Quail Chorioallantoic Membrane

NASA Technical Reports Server (NTRS)

Henry, M. K.; Unsworth, B. R.; Sychev, B. R.; Guryeva, T. S.; Dadasheva, O. A.; Piert, S. J.; Lagel, K. E.; Dubrovin, L. C.; Jahns, G. C.; Boda, K.;

Suitability of Microtheca ochroloma (Coleoptera: Chrysomelidae) for the Development of the Predator Chrysoperla rufilabris (Neuroptera: Chrysopidae).

PubMed

Niño, Angie A; Cave, Ronald D

2015-08-01

Microtheca ochroloma Stål, the yellowmargined leaf beetle, is one of the most destructive pests of crucifer vegetables on organic farms. Larvae of the green lacewing Chrysoperla rufilabris Burmeister have been observed preying on M. ochroloma, but no studies have evaluated the suitability of M. ochroloma as prey for C. rufilabris or the efficacy of this predator as a biological control agent of the pest. This study quantified the killing rate, developmental time, and survivorship of C. rufilabris when offered eggs and larvae of M. ochroloma at 10, 15, 20, or 25°C. Mean number of prey killed daily increased from 8.4 eggs and 4.0 larvae at 15°C to 18.6 eggs and 10.2 larvae at 25°C. However, predator larvae killed 78% fewer total eggs at 25°C than at 15°C; total number of first-instar prey killed did not vary significantly with temperature. Mean developmental time of predator larvae decreased from 75.5 d at 15°C to 26.6 d at 25°C when they were fed eggs, whereas it decreased from 54.0 d at 15°C to 21.4 d at 25°C when they were fed larvae. Predator survivorship was reduced by 80% at 15°C and no larvae survived at 10°C. We conclude that C. rufilabris can complete development on a diet of eggs of M. ochroloma, but its effectiveness to control M. ochroloma populations will be lessened during cool months, from November to April, when crucifers are produced in Florida and the beetle is actively developing, reproducing, and causing crop damage. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Early development of the longsnout seahorse Hippocampus reidi (Syngnathidae) within the male brood pouch.

PubMed

Novelli, B; Otero Ferrer, F; Socorro, J A; Molina Domínguez, L

2018-06-01

Fertilized and unfertilized eggs and embryos of the longsnout seahorse Hippocampus reidi were collected at different stages of development and provided the basis for a description of morphological development from fertilization until release from the paternal pouch. Images of fertilized eggs, as well as their rupture after a few minutes in seawater are reported for the first time. The yolk sac transitioned from ovoid to spherical shape and was reabsorbed progressively until release. The tail began rising from the surface of the deuteroplasm while embryos were in the egg envelope. Embryos lacked a primordial fin fold and developed some species characteristics, such as rays in the dorsal fin, before resorption of the yolk sac. At release, juvenile seahorses were in an advanced stage of development even if they lacked important adult characteristics, such as ring plates and coronet. The tail was not prehensile in juveniles at release; a small caudal fin was present, although this fin is lost in adults. © 2018 The Fisheries Society of the British Isles.

Impact of virus strain characteristics on early detection of highly pathogenic avian influenza infection in commercial table-egg layer flocks and implications for outbreak control.

PubMed

Weaver, J Todd; Malladi, Sasidhar; Goldsmith, Timothy J; Hueston, Will; Hennessey, Morgan; Lee, Brendan; Voss, Shauna; Funk, Janel; Der, Christina; Bjork, Kathe E; Clouse, Timothy L; Halvorson, David A

2012-12-01

Early detection of highly pathogenic avian influenza (HPAI) infection in commercial poultry flocks is a critical component of outbreak control. Reducing the time to detect HPAI infection can reduce the risk of disease transmission to other flocks. The timeliness of different types of detection triggers could be dependent on clinical signs that are first observed in a flock, signs that might vary due to HPAI virus strain characteristics. We developed a stochastic disease transmission model to evaluate how transmission characteristics of various HPAI strains might effect the relative importance of increased mortality, drop in egg production, or daily real-time reverse transcriptase (RRT)-PCR testing, toward detecting HPAI infection in a commercial table-egg layer flock. On average, daily RRT-PCR testing resulted in the shortest time to detection (from 3.5 to 6.1 days) depending on the HPAI virus strain and was less variable over a range of transmission parameters compared with other triggers evaluated. Our results indicate that a trigger to detect a drop in egg production would be useful for HPAI virus strains with long infectious periods (6-8 days) and including an egg-drop detection trigger in emergency response plans would lead to earlier and consistent reporting in some cases. We discuss implications for outbreak control and risk of HPAI spread attributed to different HPAI strain characteristics where an increase in mortality or a drop in egg production or both would be among the first clinical signs observed in an infected flock.

Formation and structural organization of the egg-sperm bundle of the scleractinian coral Montipora capitata

NASA Astrophysics Data System (ADS)

Padilla-Gamiño, J. L.; Weatherby, T. M.; Waller, R. G.; Gates, R. D.

2011-06-01

The majority of scleractinian corals are hermaphrodites that broadcast spawn their gametes separately or packaged as egg-sperm bundles during spawning events that are timed to the lunar cycle. The egg-sperm bundle is an efficient way of transporting gametes to the ocean surface where fertilization takes place, while minimizing sperm dilution and maximizing the opportunity for gamete encounters during a spawning event. To date, there are few studies that focus on the formation and structure of egg-sperm bundle. This study explores formation, ultrastructure, and longevity of the egg-sperm bundle in Montipora capitata, a major reef building coral in Hawai`i. Our results show that the egg-sperm bundle is formed by a mucus layer secreted by the oocytes. The sperm package is located at the center of each bundle, possibly reflecting the development of male and female gametes in different mesenteries. Once the egg-sperm bundle has reached the ocean surface, it breaks open within 10-35 min, depending on the environmental conditions (i.e., wind, water turbulence). Although the bundle has an ephemeral life span, the formation of an egg-sperm bundle is a fundamental part of the reproductive process that could be strongly influenced by climate change and deterioration of water quality (due to anthropogenic effects) and thus requires further investigation.

Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese painted quail, and the effect of egg clutch position on embryonic development.

PubMed

Parker, H M; McDaniel, C D

2009-04-01

Parthenogenesis, embryonic development of an unfertilized egg, was studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis should increase our knowledge of avian fertilization and early embryonic development. Therefore, we determined if unfertilized Chinese painted quail hens produce embryos. Second, we explored the possibility that position of the egg within the clutch influences parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 6 wk of age. Individual eggs were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 degrees C before incubation at 37.5 degrees C. After 10 d of incubation, approximately 4,000 eggs from 300 laying hens were examined for embryonic development under a magnifying lamp. On average, 4.8% of the unfertilized eggs contained an abortive form of embryonic development consisting of undifferentiated cells and unorganized membranes. Approximately 27% of the laying hens produced at least 1 egg with parthenogenic development. However, about 10% (30) of these hens exhibited a predisposition for parthenogenesis by producing 2 or more unfertilized eggs with embryonic development. Twenty percent of the eggs from 2 hens produced embryonic development. Additionally, the first egg laid in a clutch was most likely to produce embryonic development, with a steady decline in the percentage of eggs with embryonic development as position in the clutch increased. In conclusion, the Chinese painted quail does exhibit parthenogenesis and clutch position influences the rate of naturally occurring parthenogenesis.

Producibility Engineering and Planning for Tray Pack Foods

DTIC Science & Technology

1987-09-07

roast w gravy 1.0 15.0 36.5 0.067 2.433 1.852 073 Eggs ,scrambled w/ ham 2.0 20.0 36.5 0.100 3.650 2.778 074 Egg loaf-i/ cheddar 2.0 20.0 36.5 0.100 3.650...Persons eating under the Ten-Day Basic Meal Plan Cycle consume by volume approximately-- (1) 3 1/2 times more meat and eggs (entrees) than...vegetables. (2) 2 1/2 times more meat and eggs than starches. (3) 20% more meat and eggs than fruits and desserts. (4) 3 times more fruits and desserts than

Management of Sexual Maturation and Natural Spawning of Captive- Reared Yellowtail Kingfish, Seriola lalandi, in an Indoor Rearing Tank.

PubMed

Yang, Sang Geun; Ji, Seung Cheol; Lim, Sang Gu; Hur, Sang Woo; Jeong, Minhwan; Lee, Chi Hoon; Kim, Bong Seok; Lee, Young-Don

2016-06-01

This study describes results on sexual maturation and characteristics of natural spawned eggs to develop a method for the production of stable, healthy fertilized eggs from captive-reared yellowtail kingfish, Seriola lalandi. A total of 59 yellowtail kingfish were captured off the coast of Jeju Island, after which the broodstock was cultured in indoor culture tank (100 m(3)) until they were 6.1-14.9 kg in body weight. As part of the rearing management for induced sex maturation, the intensity of illumination was maintained at 130 lux. The photoperiod (light/dark; L/D) was set to a 12 L/12 D from October 2013 to January 2014, and 15 L/9 D from February 2014 to June 2014. Feeds comprised mainly EP (Extruded Pellets), with squid cuttlefish added for improvement of egg quality, and was given from April to June 2014. The first spawning of yellowtail kingfish occurred in May 3, 2014, at a water temperature of 17.0°C. Spawning continued until June 12, 2014, with the water temperature set at 20.5°C. Time of spawning was 26 times at this period. The total number of eggs that spawned during the spawning period was 4,449×10(3). The buoyant rate of spawning eggs and fertilization rate of buoyant eggs during the spawned period were 76.1% and 100%, respectively. The diameters of the egg and oil globule were 1.388 ± 0.041 mm and 0.378 ± 0.029 mm, respectively, which was higher in early eggs than in those from late during the spawned period.

Biology and Life History of Balcha indica, an Ectoparasitoid Attacking the Emerald Ash Borer, Agrilus planipennis, in North America

PubMed Central

Duan, Jian J.; Taylor, Philip B.; Fuester, Roger W.

2011-01-01

Balcha indica Mani and Kaul (Hymenoptera: Eupelmidae) is a solitary ectoparasitoid attacking larvae, prepupae, and pupae of the emerald ash borer, Agrilus planipennis Fairmaire (Hymenoptera: Eupelmidae). Its fecundity, oviposition rate, longevity, and development time were determined in the laboratory under standard rearing conditions (25 ± 2° C, 65 ± 10% relative humidity, and 14:10 L:D). Adults lived a mean of 59 days with a maximum of 117 days. Lifetime adult fecundity averaged 36 eggs with a maximum 94 eggs per female. The egg stage lasted for a maximum of four days with ∼ 50% eggs hatched within two days. The development time of the first instars lasted for a maximum of nine days; 50% of the first instars completed their development (i.e., molted to the next instar) within five days. Instars of the intermediate and final stage larvae (after molting of the first instars occurred) could not be distinguished until they reached the pupal stage, and 50% of those larvae pupated ∼ 62 days after adult oviposition. Under the standard rearing conditions, 50% of B. indica took ∼ 83 days to complete the life cycle (from egg to adult emergence) ranging from 47 to 129 days. These results suggest that B. indica may not have more than two generations in the mid-Atlantic and Midwest regions of United States, where normal growing seasons—with average temperature above 25° C—are normally less than six months (May–October). Because of the long life span and oviposition period of adults, however, B. indica is likely to have overlapping generations. PMID:22233385

Taenia eggs in a stabilization pond system with poor hydraulics: concern for human cysticercosis?

PubMed

Verbyla, Matthew E; Oakley, Stewart M; Lizima, Louis A; Zhang, Jie; Iriarte, Mercedes; Tejada-Martinez, Andres E; Mihelcic, James R

2013-01-01

The objective of this study is to compare the removal of Taenia eggs to the removal of Ascaris eggs in a wastewater stabilization pond system consisting of three ponds in series, where the hydraulic residence time distribution has been characterized via a tracer study supported by computational fluid dynamics modeling. Despite a theoretical hydraulic retention time of 30 days, the peak dye concentration was measured in the effluent of the first pond after only 26 hours. The smaller-sized Taenia eggs were detected in higher concentrations than Ascaris eggs in the raw wastewater. Ascaris eggs were not detected in the pond system effluent, but 45 Taenia eggs/L were detected in the system effluent. If some of these eggs were of the species Taenia solium, and if the treated wastewater were used for the irrigation of crops for human consumption, farmers and consumers could potentially be at risk for neurocysticercosis. Thus, limits for Taenia eggs in irrigation water should be established, and precautions should be taken in regions where pig taeniasis is endemic. The results of this study indicate that the theoretical hydraulic retention time (volume/flow) of a pond is not always a good surrogate for helminth egg removal.

Quantification of the heat exchange of chicken eggs.

PubMed

Van Brecht, A; Hens, H; Lemaire, J L; Aerts, J M; Degraeve, P; Berckmans, D

2005-03-01

In the incubation process of domestic avian eggs, the development of the embryo is mainly influenced by the physical microenvironment around the egg. Only small spatiotemporal deviations in the optimal incubator air temperature are allowed to optimize hatchability and hatchling quality. The temperature of the embryo depends on 3 factors: (1) the air temperature, (2) the exchange of heat between the egg and its microenvironment and (3) the time-variable heat production of the embryo. Theoretical estimates on the heat exchange between an egg and its physical microenvironment are approximated using equations that assume an approximate spherical shape for eggs. The objective of this research was to determine the heat transfer between the eggshell and its microenvironment and then compare this value to various theoretical estimates. By using experimental data, the overall and the convective heat transfer coefficients were determined as a function of heat production, air humidity, air speed, and air temperature. Heat transfer was not affected by air humidity but solely by air temperature, embryonic heat generation, and air speed and flow around eggs. Also, heat transfer in forced-air incubators occurs mainly by convective heat loss, which is dependent on the speed of airflow. A vertical airflow is more efficient than a horizontal airflow in transferring heat from the egg. We showed that describing an egg as a sphere underestimated convective heat transfer by 33% and was, therefore, too simplistic to accurately assess actual heat transfer from real eggs.

Effects of storage time and temperature on lipid oxidation of egg powders enriched with natural antioxidants.

PubMed

Matumoto-Pintro, Paula Toshimi; Murakami, Alice Eiko; Vital, Ana Carolina Pelaes; Croge, Camila; da Silva, Denise Felix; Ospina-Roja, Ivan Camilo; Guerra, Ana Flávia Quiles Garcia

2017-08-01

The lipid fraction of egg powder may be affected by storage conditions due to the development of oxidative rancidity caused by polyunsaturated fatty acids. This study evaluated egg powders enriched with antioxidants [tocopherol, catechin, lycopene, and butylated hydroxyanisole (BHA)] for conjugated dienes (during a 90-day period) and for malonaldehydes (during a 210-day period) at 25±2 and 4±1°C. The presence of lycopene and BHA increases the total phenolic compounds in the enriched egg powders, and BHA exhibits the most antioxidant activity, as quantified by an ABTS assay. Egg powders enriched with antioxidants do not show any reduction in conjugate diene production compared to controls, and no effect of storage temperature is observed; however, in the production of malonaldehyde, greater stability is observed at 4°C, and catechin is more effective in reducing oxidation during storage. The results show that natural antioxidants can be used in egg powder instead of synthetic compounds to reduce malonaldehyde production during storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diapause and prolonged development in the embryo and their ecological significance in two cicadas, Cryptotympana facialis and Graptopsaltria nigrofuscata.

PubMed

Moriyama, Minoru; Numata, Hideharu

2008-12-01

The seasonal timing mechanism of egg hatching was examined in two cicadas, Cryptotympana facialis and Graptopsaltria nigrofuscata, with different but overlapping geographical distributions. These species lay eggs in summer, and nymphs hatch in the summer of the following year after egg durations of 10-12 months. When eggs were maintained at 25 degrees C from oviposition, both the species entered embryonic diapause within 60 days irrespective of photoperiod, but at different developmental stages between the two species. The optimal temperature for diapause development was approximately 15 degrees C in both the species. The development rate for postdiapause morphogenesis increased linearly with temperature in the range of 20-27.5 degrees C in C. facialis, and of 15-25 degrees C in G. nigrofuscata. The lower development threshold and the sum of effective temperatures were computed as 14.3 degrees C and 715.3 day-degrees in C. facialis and 12.1 degrees C and 566.6 day-degrees in G. nigrofuscata, respectively. The hatching dates predicted by these large thermal constants accorded with the hatching dates observed in the field, i.e., late June and mid-July in G. nigrofuscata and C. facialis, respectively. Therefore, the high thermal requirements for postdiapause development compel the cicadas to hatch in summer.

The case for a cause-effect linkage between environmental contamination and development in eggs of the common snapping turtle (Chelydra S. serpentina) from Ontario, Canada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bishop, C.A.; Brooks, R.J.; Carey, J.H.

1991-08-01

Concentrations of polychlorinated biphenyls (PCBs), dibenzo-p-dioxins, and dibenzofurans, organochlorine pesticides, and their metabolites were measured in eggs of the common snapping turtle (Chelydra s.serpentina) collected from four wetlands on the shorelines of Lakes Ontario, and Erie, and one control location in central Ontario, Canada. Snapping turtle eggs from these sites were also artificially incubated to determine hatching success, and incidence of deformities in embryo and hatchling turtles. The hypothesis that elevated incidences of egg death and/or deformities of hatchling turtles would occur in populations with high concentrations of organochlorine contaminants in eggs was tested. The results were elevated using epidemiologicalmore » criteria. Unhatched eggs and deformities occurred at significantly higher rates in eggs from Lake Ontario wetlands. Two of three sites from Lake Ontario had substantially higher levels of PCBs, dioxins, and furans compared to eggs from Lake Erie and the control site. It could not be shown that contamination of eggs preceded the occurrence of poor development of eggs, although excellent hatching success and low numbers of deformities in eggs from the control site were considered representative of development in healthy eggs. The statistical association between contaminant levels in eggs and poor development of these eggs supported the hypothesis that eggs from sites with the greatest contamination had the highest rates of abnormalities. PCBs were the most strongly associated chemicals, although possible effects due to the presence of other chemicals in eggs was a confounding factor. The deformities and rates of unhatched eggs were similar to those occurring in other vertebrates collected from highly contaminated areas of the Great Lakes. 54 references.« less

Effects of temperature and photoperiod on the aestivo-hibernal egg diapause of Scymnus camptodromus (Coleoptera: Coccinellidae).

PubMed

Keena, Melody A; Trotter, R Talbot; Cheah, Carole; Montgomery, Michael E

2012-12-01

Three sequential studies were conducted on the interacting effects of exposure to low (5°C) temperature for 0, 7, 28, 56, or 84 d followed by incubation at 10, 15, or 20°C on the egg diapause of Scymnus (Neopullus) camptodromus Yu and Liu (Coleoptera: Coccinellidae). This beetle was imported from China as a potential biological control agent for hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae). Very few eggs laid and held at a constant 15 or 20°C showed any indication of development. Only eggs exposed to temperature combinations of 5 and 10°C had >50% hatch. Highest percent hatch and fastest development occurred when eggs were held at 5°C for 56 or 84 d followed by holding at 10°C. A model estimated the lower threshold for postdiapause development to be 2°C. The effect of temperature on egg hatch was similar at photoperiods of 12:12 and 16:8 (L:D) h, suggesting egg development is not governed by photoperiod or light exposure. Collectively these data indicate that S. camptodromus eggs laid in the spring and summer go through an aestivo-hibernal diapause that is maintained by warm temperatures and that development resumes when temperatures drop, in parallel with the development of hemlock woolly adelgid. This concurrent development allows S. camptodromus eggs to hatch while hemlock woolly adelgid is laying eggs. This synchrony between the development of S. camptodromus eggs and the overwintering adelgid suggest this beetle may be a good candidate for the biological control of the hemlock woolly adelgid.

Effects of host genetics and environment on egg-associated microbiotas in brown trout (Salmo trutta).

PubMed

Wilkins, Laetitia G E; Fumagalli, Luca; Wedekind, Claus

2016-10-01

Recent studies found fish egg-specific bacterial communities that changed over the course of embryogenesis, suggesting an interaction between the developing host and its microbiota. Indeed, single-strain infections demonstrated that the virulence of opportunistic bacteria is influenced by environmental factors and host immune genes. However, the interplay between a fish embryo host and its microbiota has not been studied yet at the community level. To test whether host genetics affects the assemblage of egg-associated bacteria, adult brown trout (Salmo trutta) were sampled from a natural population. Their gametes were used for full-factorial in vitro fertilizations to separate sire from dam effects. In total, 2520 embryos were singly raised under experimental conditions that differently support microbial growth. High-throughput 16S rRNA amplicon sequencing was applied to characterize bacterial communities on milt and fertilized eggs across treatments. Dam and sire identity influenced embryo mortality, time until hatching and composition of egg-associated microbiotas, but no link between bacterial communities on milt and on fertilized eggs could be found. Elevated resources increased embryo mortality and modified bacterial communities with a shift in their putative functional potential. Resource availability did not significantly affect any parental effects on embryo performance. Sire identity affected bacterial diversity that turned out to be a significant predictor of hatching time: embryos associated with high bacterial diversity hatched later. We conclude that both host genetics and the availability of resources define diversity and composition of egg-associated bacterial communities that then affect the life history of their hosts. © 2016 John Wiley & Sons Ltd.

Rats and seabirds: effects of egg size on predation risk and the potential of conditioned taste aversion as a mitigation method.

PubMed

Latorre, Lucía; Larrinaga, Asier R; Santamaría, Luis

2013-01-01

Seabirds nesting on islands are threatened by invasive rodents, such as mice and rats, which may attack eggs, chicks and even adults. The low feasibility of rat eradications on many islands makes the development of alternate control plans necessary. We used a combination of field experiments on a Mediterranean island invaded by black rats (Rattusrattus) to evaluate (1) the predation risk posed to different-sized seabird eggs and (2), the potential of two deterrent methods (electronic and chemical) to reduce its impact. Rats were able to consume eggs of all sizes (12 to 68 g), but survival increased 13 times from the smallest to the largest eggs (which also had more resistant eggshells). Extrapolation to seabird eggs suggests that the smallest species (Hydrobatespelagicus) suffer the most severe predation risk, but even the largest (Larusmichahellis) could suffer >60% mortality. Nest attack was not reduced by the deterrents. However, chemical deterrence (conditioned taste aversion by lithium chloride) slowed the increase in predation rate over time, which resulted in a three-fold increase in egg survival to predation as compared to both control and electronic deterrence. At the end of the experimental period, this effect was confirmed by a treatment swap, which showed that conferred protection remains at least 15 days after cessation of the treatment. Results indicate that small seabird species are likely to suffer severe rates of nest predation by rats and that conditioned taste aversion, but not electronic repellents, may represent a suitable method to protect colonies when eradication or control is not feasible or cost-effective.

Experimental changes of the cleavage pattern in the eggs of a gall midge (Wachtliella persicariae L.) after local ultrasonic treatment.

PubMed

Wolf, Rainer

1972-12-01

To affirm the hypothesis that during the early cleavage inWachtliella persicariae L., central and marginal ooplasm do not only differ by their kinematic aspects (Wolf, 1969; Wolf and Krause, 1971) but also physiologically, the radial symmetry of the ooplasm has been destroyed experimentally. For this purpose a device has been developed permitting a local ultrasonic treatment of insect eggs limited to well defined regions of various sizes (Fig. 1). The changes in the egg architecture can be observed directly while the treatment is going on and their effects on embryogenesis are analyzed by time-lapse motion pictures.Cleavage nuclei which have been transferred prematurely to the egg surface during low-intensity ultrasonic radiation of the whole egg length (Fig. 2 a), move back into the central ooplasm after treatment; the marginal plasm becomes populated only later at the same time as in untreated eggs. Local high-intensity ultrasonic treatment, too (Fig. 2 c), obviously does not cause any damage to the nuclei, while the ooplasm within the treated area becomes completely mixed up. After exposure the untreated region may become partially coated by a sheath of mixed up ooplasm. The populating of the egg surface by the nuclei is restricted to those sites where the untreated marginal ooplasm remains at the surface. These are the only areas for the later formation of preblastoderm and blastoderm. For the normal distribution of the cleavage energides a certain ooplasmic component sensitive to ultrasonic treatment seems to be responsible, the ultrastructure of which will be subjected to further investigations.

Carry-over effects modulated by salinity during the early ontogeny of the euryhaline crab Hemigrapsus crenulatus from the Southeastern Pacific coast: Development time and carbon and energy content of offspring.

PubMed

Urzúa, Ángel; Bascur, Miguel; Guzmán, Fabián; Urbina, Mauricio

2018-03-01

Hemigrapsus crenulatus is a key species of coastal and estuarine ecosystems in the Southeastern Pacific and New Zealand. Since the gravid females-and their embryos-develop under conditions of variable salinity, we propose that low external salinity will be met with an increase in energy expenditures in order to maintain osmoregulation; subsequently, the use of energy reserves for reproduction will be affected. In this study, we investigate in H. crenulatus whether 1) the biomass and energy content of embryos is influenced by salinity experienced during oogenesis and embryogenesis and 2) how variation in the biomass and energy content of embryos affects larval energetic condition at hatching. Here at low salinity (5PSU), egg-bearing females experienced massive and frequent egg losses, and therefore the development of their eggs during embryogenesis was not completed. In turn, at intermediate and high salinity (15 and 30PSU) embryogenesis was completed, egg development was successful, and larvae were obtained. Consistently, larvae hatched from eggs produced and incubated at high salinity (30PSU) were larger, had higher dry weight, and had increased carbon content and energy than larvae hatched from eggs produced at intermediate salinity (15PSU). From these results, it is seen that the size and biomass of early life stages of H. crenulatus can be affected by environmental salinity experienced during oogenesis and embryogenesis, and this variation can then directly affect the energetic condition of offspring at birth. Therefore, this study reveals a "cascade effect" modulated by salinity during the early ontogeny. Copyright © 2018 Elsevier Inc. All rights reserved.

Upper jurassic dinosaur egg from utah.

PubMed

Hirsch, K F; Stadtman, K L; Miller, W E; Madsen, J H

1989-03-31

The Upper Jurassic egg described here is the first known egg from the 100-million-year gap in the fossil record between Lower Jurassic (South Africa) and upper Lower Cretaceous (Utah). The discovery of the egg, which was found mixed in with thousands of dinosaur bones rather than in a nest, the pathological multilayering of the eggshell as found in modern and fossil reptilians, and the pliable condition of the eggshell at the time of burial indicate an oviducal retention of the egg at the time of burial.

Factors affecting thermal resistance of Salmonella enterica serovar enteritidis ODA 99-30581-13 in shell egg contents and use of heat-ozone combinations for egg pasteurization.

PubMed

Perry, Jennifer J; Yousef, Ahmed E

2013-02-01

Infection of laying hens with Salmonella enterica serovar Enteritidis leads to deposition of the pathogen into the albumen or yolk of forming eggs. Heat treatment can inactivate internalized Salmonella Enteritidis in shell eggs, but factors such as the nature and location of contamination may influence the efficacy of thermal treatments. In the current research, natural contamination was mimicked by introducing small inocula of Salmonella Enteritidis into different locations of shell eggs and incubating inoculated eggs. These pathogen-containing eggs were heated at 57°C for 40 min, and temperature within eggs was monitored at the locations of inocula. Comparison of inactivation at equivalent internal temperatures revealed similar levels of lethality regardless of inoculum location. Refrigeration between incubation and heat treatment did not increase thermal resistance of cells in albumen but decreased cell inactivation in yolk. Sequential application of heat and gaseous ozone allows for the development of a process capable of decontaminating shell eggs with minimal thermal treatment and impact on egg quality. Inoculated eggs were subjected to (i) an immersion heating process similar to that used in commercial pasteurization or (ii) immersion heating, at reduced duration, followed by vacuum (50.8 kPa) and treatment with ozone gas (maximum 160 g/m(3)) under pressure (∼187.5 kPa). All treatments tested produced greater than 5-log inactivation, which is required for "pasteurization" processes. Differences were observed in the visual quality of eggs depending on treatment parameters. Application of ozone subsequent to heating allows for a significant reduction in heating time without decreasing process lethality.

Study on mixis potential of rotifer resting eggs ( Brachionus plicatilis) with different collection times and different preservation periods

NASA Astrophysics Data System (ADS)

Zhou, Li; Zheng, Yan; Xiang, Jian-Hai

2001-09-01

The present study investigated the possible changes in the mixis potential of rotifer resting eggs produced by a single stock of Brachionus plicatilis and collected and preserved annually from 1985 1998. Several clones derived from each batch of resting eggs were cultured under the same conditions for 21 days. The percentage of clones appearing resting eggs and the average yield of resting eggs produced from each clone were recorded and statistically analyzed to find the differences between the mixis potential of those resting egg batches. Results showed that different batches of resting eggs had different mictic levels among their descendent clones; but no regular relationship was found between the mixis potential of resting eggs and their collection times/preservation periods. Several internal and external factors that might affect the mixis potential of resting eggs were discussed.

Embryotoxicity of weathered crude oil from the Gulf of Mexico in mallard ducks (Anas platyrhynchos).

PubMed

Finch, Bryson E; Wooten, Kimberly J; Smith, Philip N

2011-08-01

Weathered crude oil in the Gulf of Mexico can result from oil spills such as the Deepwater Horizon incident that occurred on April 20, 2010 or from natural seeps. Adult waterbirds of the Gulf Coast region may become exposed to weathered crude oil while foraging, wading, or resting, and residues can then be transferred to nests, eggs, and hatchlings. Although the toxicity of many types of crude oil to avian embryos has been thoroughly studied, the effects of weathered crude oil on developing avian embryos are not well characterized. The objective of the present study was to examine embryotoxicity of weathered crude oil collected from the Gulf of Mexico in June 2010 using mallard ducks (Anas platyrhynchos) as a model species. Weathered crude oil was applied to fertilized mallard duck eggs by paintbrush in masses ranging from 0.1 to 99.9 mg on day 3 of incubation. Mortality occurred as early as day 7 and the conservatively derived median lethal application of weathered crude oil was 30.8 mg/egg (0.5 mg/g egg) or 30.7 µl/egg (0.5 µl/g egg). Body mass, liver and spleen mass, crown-rump and bill lengths, and frequency of deformities were not significantly different among hatchlings from oiled and control eggs. In comparison to published reports of fresh crude oil embryotoxicity, weathered crude oil was considerably less toxic. We conclude that avian toxicity varies according to the degree of crude oil weathering and the stage of embryonic development at the time of exposure. Results indicate bird eggs exposed to weathered crude oil from the Gulf of Mexico during summer 2010 may have had reduced hatching success. Copyright © 2011 SETAC.

Infestation of grain fields and degree-day phenology of the cereal leaf beetle (Coleoptera: Chrysomelidae) in Utah: long-term patterns.

PubMed

Evans, Edward W; Carlile, Nolan R; Innes, Matthew B; Pitigala, Nadishan

2014-02-01

Scouting at key times in the seasonal development of insect pest populations, as guided by degree-day accumulation, is important for minimizing unwarranted insecticide application. Fields of small grains in northern Utah were censused weekly from 2001 to 2011, to assess infestation by the cereal leaf beetle, Oulema melanopus (L.) (Coleoptera: Chrysomelidae), and develop degree-day guidelines for measuring cereal leaf beetle abundance at peak egg and larval densities in any given year. Even in years of high overall numbers of cereal leaf beetle, relatively few fields were heavily infested (with 20 or more cereal leaf beetle eggs + larvae per 0.09 m2) at either egg or larval peak density during the growing season. In individual fields, the number of immature cereal leaf beetle (eggs + larvae) at peak larval density was positively related to the number of immature cereal leaf beetles present earlier at peak egg density. Although there was large variation among years in when cereal leaf beetle egg and larval numbers peaked during the season as measured by degree-day accumulation from 1 January, much of this variation was accounted for by the warmth of the early spring before significant egg laying occurred. Hence, degree-day estimates that account for early spring warmth can guide growers in scouting grain fields at peak egg densities to identify fields at high risk of subsequent economic damage from cereal leaf beetle larval feeding. The relatively low incidence of fields heavily infested by cereal leaf beetle in northern Utah emphasizes the benefit that growers can gain by scouting early before applying insecticide treatments.

First assessment of trace metal concentration in mangrove crab eggs and other tissues, SE Brazil.

PubMed

de Almeida, Eduardo Vianna; Kütter, Vinicius Tavares; Marques, Eduardo Duarte; da Silva-Filho, Emmanoel Vieira

2016-07-01

The mangrove crab Ucides cordatus is widespread in the Brazilian coast, which has an important role in nutrient cycling. This species reproduces in summer and females carry eggs about a month, when they maintain contact with water and sediments. It remains unclear if trace metals can be absorbed or adsorbed by the eggs during development. The present study aims to investigate, for the first time, trace metal concentrations in ovigerous female tissues and eggs of U. cordatus in two areas with different metal pollution levels in the Southeastern Brazil. Samples were collected in two different mangroves, Guanabara Bay (GB) highly polluted environment and Paraíba do Sul River (PSR). In both populations, we observed significant increase of V, Cr, and Mn concentrations along eggs maturation. The higher metals averages were found in PSR population. This trend was reported since the 1990s and lower concentrations in GB marine organisms were attributed to reducing conditions, high organic load, and the presence of sulfide ions. These conditions restrict the bioavailability of metals in the bay, with exception of Mn. No significant differences were observed in gills and muscles. In both populations of the present study, V, Zn, As, and Pb were higher in eggs of initial stage, whereas Mn, Ni, Cu, and Cd were higher in hepatopancreas. Beside this, V, Cr, Mn, As, and Pb showed an increase concerning egg development. Thus, V, As, and Pb in eggs come from two sources previous discussed: females and environment. Zinc came mainly from females due to essential function. Those new information should be considered as one of the mechanisms of trace metal transfer to the trophic chain, between benthonic and pelagic environment.

Effects of salting processes and time on the chemical composition, textural properties, and microstructure of cooked duck egg.

PubMed

Kaewmanee, Thammarat; Benjakul, Soottawat; Visessanguan, Wonnop

2011-03-01

Chemical composition, textural properties, and microstructure of cooked duck egg salted by 2 methods (coating and immersing) were determined during 4 wk of salting. As the salting time increased, moisture content increased and salt content decreased for both cooked salted egg white and yolk. Oil exudation of cooked yolk and expressible water content of cooked egg white obtained from both salting methods increased as salting proceeded (P < 0.05). After cooking, oil exudation accompanied by the solubilized pigments, especially at the outer layer of yolk, was obtained. At week 3 of salting, egg yolk from coating method had the higher egg exudation than that from immersing method. As the salting times increased, the lower hardness, springiness, gumminess, chewiness, and resilience with higher adhesiveness and cohesiveness were generally found in cooked salted egg white (P < 0.05), irrespective of salting methods. Conversely, the hardness of cooked yolk increased continuously and reached the maximum at week 2 and 2 to 3 for immersing and coating method (P < 0.05), respectively. Confocal laser scanning micrographs revealed the smaller yolk granules with more release of free lipid in salted egg after heating, compared with the fresh counterpart. As visualized by scanning electron microscope, gel of cooked salted egg white was coagulum type with larger voids. Salting methods determined oil exudation in egg yolk and texture profile of egg white gel after cooking; however, those attributes were also governed by the salting time. Salted duck egg can be made by 2 methods (coating and immersing) affecting the characteristic of salted egg white and yolk after cooking. Desirable cooked salted egg having the red yolk with hardness and high oil exudation could be obtained when salting was carried out for 3 and 4 wk for immersing and coating method, respectively.

Artificial light at night prolongs juvenile development time in the black field cricket, Teleogryllus commodus.

PubMed

Durrant, Joanna; Botha, L Michael; Green, Mark P; Jones, Therésa M

2018-06-01

A growing body of evidence exists to support a detrimental effect of the presence of artificial light at night (ALAN) on life-history and fitness traits. However, few studies simultaneously investigate multiple traits and the life stages at which changes manifest. We experimentally manipulated ALAN intensities, within those found in the natural environment, to explore the consequences for growth, survival, and reproductive success of the field cricket, Teleogryllus commodus. We reared crickets from egg to adult under a daily light-cycle consisting of 12 hr bright daylight (2,600 lx) followed by either 12 hr darkness (0 lx) or dim-light environments (1, 10, or 100 lx). We found egg hatch, adult survival, and reproductive measures were largely comparable for all treatments. However, juvenile development time (number of days from egg to adult) was on average 10 days (14%) longer and adults were also larger when crickets were exposed to any light at night (1, 10, or 100 lx). Our data demonstrate that chronic lifetime exposure to ALAN can modulate the timing of life-history events and may disrupt phenology to a similar extent as other abiotic factors. © 2018 Wiley Periodicals, Inc.

Simultaneous Measurement of Thermophysical Properties of Tissue-Mimicking Phantoms for High Intensity Focused Ultrasound (HIFU) Exposures

NASA Astrophysics Data System (ADS)

Gao, Jing; You, Jiang; Huang, Zhihong; Cochran, Sandy; Corner, George

2012-03-01

Tissue-mimicking phantoms, including bovine serum albumin phantoms and egg white phantoms, have been developed for, and in laboratory use for, real-time visualization of high intensity focused ultrasound-induced thermal coagulative necrosis since 2001. However, until now, very few data are available concerning their thermophysical properties. In this article, a step-wise transient plane source method has been used to determine the values of thermal conductivity, thermal diffusivity, and specific heat capacity of egg white phantoms with elevated egg white concentrations (0 v/v% to 40 v/v%, by 10 v/v% interval) at room temperature (~20 °C). The measured thermophysical properties were close to previously reported values; the thermal conductivity and thermal diffusivity were linearly proportional to the egg white concentration within the investigation range, while the specific heat capacity decreased as the egg white concentration increased. Taking account of large differences between real experiment and ideal model, data variations within 20 % were accepted.

Rearing and colonization of Lutzomyia evansi (Diptera: Psychodidae), a vector of visceral leishmaniasis in Colombia.

PubMed

Montoya-Lerma, J; Cadena-Peña, H; Jaramillo-Salazar, C

1998-01-01

The sandfly Lutzomyia evansi from a focus of visceral leishmaniasis in northern Columbia was reared and maintained under laboratory conditions for five generations. The average time for total development was 41.9 days (range = 35.1-49.6) at 25 degrees C and 89-95% of relative humidity. The mean number of eggs laid was lower in laboratory bred females either in pots (13.2 eggs/female) or vials (29.9 eggs/female) than in wild caught females (33.4 eggs/female). Immature mortality, mainly due to fungal and mite contamination, was higher during the first two instars than in the remaining immature stages. Adults were robust and healthy although difficult to feed on hamster or chick skin membrane. In summary, Lu. evansi is a colonizable species but requires specific conditions.

Effect of the Filamentous Fungus Mucor circinelloides On The Development of Eggs of the Rumen Fluke Calicophoron daubneyi (Paramphistomidae).

PubMed

Arroyo, Fabián; Hernández, José A; Cazapal-Monteiro, Cristiana F; Pedreira, José; Sanchís, Jaime; Romasanta, Ángel; Sánchez-Andrade, Rita; Paz-Silva, Adolfo; Arias, María S

2017-06-01

Ruminants infected by Paramphistomidae flukes shed eggs in the feces, which pass through different stages in the environment until the infective stages (metacercariae) are reached. The activity of the soil fungus Mucor circinelloides on the development of eggs of the rumen fluke Calicophoron daubneyi was presently tested with 3 probes, i.e., in petri plates, feces, and an aqueous environment (tubes). The effect of the fungus was assessed by recording the numbers of undeveloped, nonviable, and embryonated eggs. Nonviable eggs were considered when vacuolization occurred, the inner structures were not clearly observed, the eggshell was broken, or the embryo inside was destroyed. By considering the ability of hyphae of M. circinelloides to develop in the presence of C. daubneyi eggs, attach to their surface, and penetrate and destroy the inner embryo, this ovicidal effect was classified as type 3. After a period of 50 days, the percentage of undeveloped eggs in the feces of infected cattle was 40%; furthermore, 27% of the eggs were nonviable, and 33% were embryonated (1 miracidium inside). The addition of 4 doses of M. circinelloides spores directly onto the feces resulted in 9-31% undeveloped eggs, 38-60% nonviable eggs, and 9-21% embryonated eggs, and no statistical significances were obtained among the different doses. Placing the eggs of C. daubneyi into an aqueous solution containing 10 7 spores of M. circinelloides/ml for 29 days resulted in 43% undeveloped eggs, 40% nonviable eggs, and 17% embryonated eggs, whereas in the controls, the percentages were 48%, 12%, and 40%, respectively. These data demonstrate the usefulness of the spores of the fungus M. circinelloides in limiting the development of the eggs of the trematode C. daubneyi.

Identification and expression analysis of genes involved in early ovary development in diploid gynogenetic hybrids of red crucian carp x common carp.

PubMed

Liu, Dong; Liu, Shaojun; You, Cuiping; Chen, Lin; Liu, Zhen; Liu, Liangguo; Wang, Jing; Liu, Yun

2010-04-01

Diploid eggs of allotetraploid hybrids (red crucian carp female symbol x common carp male symbol), when activated by UV-irradiated sperm of scatter scale carp, can develop into diploid progenies without chromosome duplication treatment. Diploid progenies produce diploid eggs, which develop into diploid population by the same way. To understand the molecular mechanism underlying the production of diploid eggs by the diploid fish, we constructed a forward suppression subtractive hybridization complementary DNA (cDNA) library. The cDNAs from the ovary in proliferation phase were employed as the "tester," and those in growth phase were used as the "driver." Seventy-three cDNA clones that are specifically expressed in proliferation phase were detected by dot-blot hybridization. Sequencing analyses revealed that several of these cDNAs have high homologies to the known sequences in the NCBI database. Their encoded proteins include the protein preventing mitosis catastrophe (PMC), the signal recognition particle 9, the ATP-binding cassette transporter, the glucanase-xylanase fusion protein, and others. These genes were confirmed by reverse transcriptase-polymerase chain reaction. The expression profile of the PMC gene at different time points was analyzed by quantitative real-time polymerase chain reaction. The results indicated that the expression of this suppression subtractive hybridization-identified gene changed during the time course, corresponding with the cellular phenomenon in the ovary development. Our studies provide insights into the molecular mechanism underlying the ovary development of diploid gynogenetic fish.

Effect of egg freshness on their automatic orientation.

PubMed

Jiang, Song; Zhu, Ticao; Jia, Danfeng; Yao, Jun; Jiang, Yiyi

2018-05-01

High-quality eggs in unified packaging are desired by egg production enterprises. Automatic orientation apparatus is frequently used to orient eggs uniformly to pointed-end-down position for packaging. However, such apparatus may not work accordingly if the eggs are stored under improper methods or for excessive storage time. To study the effect of egg freshness on the efficiency of automatic orientation process, the relationship between egg freshness and its orientation motions was investigated under different storage conditions. The results showed that as the storage time increased, centroid position and pointed-end-down turnover ratio decreased; other parameters such as eggs' obliquity at stationary state, horizontal deflection angle, speed, acceleration of axial motion, side-slip angle and rolling distance increased. However, the effects of storage time on the guiding distance of the guide rod were not apparent. In addition, the higher the storage temperature, the greater the changes of the final orientation states of eggs on the conveyor line. If the eggs were to be oriented uniformly, they should be stored for less than 25, 16, 10 and 7 days at 10 °C, 18 °C, 26 °C and 34 °C, respectively, under a relative humidity of 75%. The experimental results presented in this paper are very useful for quality control and quality assurance in egg production enterprises. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Expression of growth hormone gene during early development of Siberian sturgeon (Acipenser baerii)

PubMed Central

Abdolahnejad, Zeinab; Pourkazemi, Mohammad; Khoshkholgh, Majid Reza; Yarmohammadi, Mahtab

2015-01-01

The mRNA expression of growth hormone (GH) gene in early development stages of Siberian sturgeon was investigated using RT-PCR method. Samples were collected from unfertilized eggs up to 50 days post hatched (dph) larvae in 11 different times. Ribosomal protein L6 (RPL6) transcripts were used as the internal standard during quantification of GH mRNA expression. The results showed that the GH mRNA could be observed in the eyed eggs and even at unfertilized eggs of Siberian sturgeon. The highest amounts of GH mRNA were found at 25 and 50 dph larvae, while the lowest levels were detected at 1 and 3 dph larvae stage. These findings suggest that, the GH mRNA play a key role during developmental stages of Siberian sturgeon. PMID:27844010

Monitoring the hatch time of individual chicken embryos.

PubMed

Romanini, C E B; Exadaktylos, V; Tong, Q; McGonnel, I; Demmers, T G M; Bergoug, H; Eterradossi, N; Roulston, N; Garain, P; Bahr, C; Berckmans, D

2013-02-01

This study investigated variations in eggshell temperature (T(egg)) during the hatching process of broiler eggs. Temperature sensors monitored embryo temperature by registering T(egg) every minute. Measurements carried out on a sample of 40 focal eggs revealed temperature drops between 2 to 6°C during the last 3 d of incubation. Video cameras recorded the hatching process and served as the gold standard reference for manually labeling the hatch times of chicks. Comparison between T(egg) drops and the hatch time of individuals revealed a time synchronization with 99% correlation coefficient and an absolute average time difference up to 25 min. Our findings suggest that attaching temperature sensors to eggshells is a precise tool for monitoring the hatch time of individual chicks. Individual hatch monitoring registers the biological age of chicks and facilitates an accurate and reliable means to count hatching results and manage the hatch window.

Brood parasitism selects for no defence in a cuckoo host

PubMed Central

Krüger, Oliver

2011-01-01

In coevolutionary arms races, like between cuckoos and their hosts, it is easy to understand why the host is under selection favouring anti-parasitism behaviour, such as egg rejection, which can lead to parasites evolving remarkable adaptations to ‘trick’ their host, such as mimetic eggs. But what about cases where the cuckoo egg is not mimetic and where the host does not act against it? Classically, such apparently non-adaptive behaviour is put down to evolutionary lag: given enough time, egg mimicry and parasite avoidance strategies will evolve. An alternative is that absence of egg mimicry and of anti-parasite behaviour is stable. Such stability is at first sight highly paradoxical. I show, using both field and experimental data to parametrize a simulation model, that the absence of defence behaviour by Cape bulbuls (Pycnonotus capensis) against parasitic eggs of the Jacobin cuckoo (Clamator jacobinus) is optimal behaviour. The cuckoo has evolved massive eggs (double the size of bulbul eggs) with thick shells, making it very hard or impossible for the host to eject the cuckoo egg. The host could still avoid brood parasitism by nest desertion. However, higher predation and parasitism risks later in the season makes desertion more costly than accepting the cuckoo egg, a strategy aided by the fact that many cuckoo eggs are incorrectly timed, so do not hatch in time and hence do not reduce host fitness to zero. Selection will therefore prevent the continuation of any coevolutionary arms race. Non-mimetic eggs and absence of defence strategies against cuckoo eggs will be the stable, if at first sight paradoxical, result. PMID:21288944

Artificial fertilization by intracytoplasmic sperm injection in a teleost fish, the medaka (Oryzias latipes).

PubMed

Otani, Satoshi; Iwai, Toshiharu; Nakahata, Shingo; Sakai, Chiharu; Yamashita, Masakane

2009-01-01

Intracytoplasmic sperm injection (ICSI) is a technique that has been successfully used for assisting reproduction in mammals. However, this method is still not reliable in nonmammalian species, including teleosts. We succeeded in producing medaka individuals by ICSI with a rate of 13.4% (28 hatched embryos out of 209 eggs fertilized by ICSI), the best value reported so far in teleosts, including zebrafish and Nile tilapia. Although the technique was based on that developed for mammalian eggs, some critical modifications were made to adjust it to the medaka egg, which has a thick and hard envelope (the chorion) and a single sperm entry site (the micropyle). Medaka ICSI was performed by injecting a demembranated spermatozoon into an egg cytoplasm through the micropyle 10-15 sec after egg activation induced by a piezo-actuated vibration, the site and timing of sperm penetration being consistent with those in normal fertilization in medaka. To increase the efficiency of ICSI in medaka, we found that the fertilization by ICSI should precisely mimic the fertilization by insemination with intact sperm, both spatially and temporally. The success rate of ICSI was highly variable in batches of eggs (ranging from 0% to 56%), suggesting that the conditions of eggs are important factors in stabilizing the production of individuals by ICSI. The success in medaka ICSI provides a basis for future research to understand the basic mechanisms in gamete biology of teleosts as well as for development of new technology that can yield valuable applications in fisheries science.

Effects of temperature on the life-history traits of Sancassania (Caloglyphus) berlesei (Acari: Astigmatina: Acaridae) feeding on root-knot nematodes, Meloidogyne spp. (Nematoda: Meloidogynidae).

PubMed

Abou El-Atta, Doaa Abd El-Maksoud; Ghazy, Noureldin Abuelfadl; Osman, Mohamed Ali

2014-11-01

Sancassania (Caloglyphus) berlesei (Michael) is a cosmopolitan and free-living mite that inhabits soil as well as laboratory colonies of insects and fungi and may have a role as a biocontrol agent of nematodes. In this study, we investigated the effects of temperature on the development, reproduction, and food consumption of S. berlesei fed egg masses of root-knot nematodes, Meloidogyne spp., an important group of agricultural pests. Mites were reared at 20, 25 or 30 °C in the dark. The mites could feed on the nematode egg masses, and their developmental time decreased at higher temperatures. Time from the egg to adult was similar in females and males reared at the same temperature. Adult females lived longer than males at 25 °C, but not at 20 or 30 °C. Generally, females showed a higher rate of food consumption than males. Females laid the largest number of eggs at 20 and 25 °C (199.7 and 189.8 eggs/female, respectively), but the intrinsic rate of natural increase was highest at 30 °C (r m = 0.29). In comparing our data with previous reports, we noted that S. berlesei that fed on egg masses of root-knot nematodes showed a longer developmental time and a lower reproductive rate than Sancassania mites that fed on other diets. Nonetheless, the relatively high value of r m (e.g., at 25 and 30 °C) suggests that this mite may have certain advantages as a biocontrol agent of root-knot nematodes.

Effect of different constant incubation temperatures on egg survival and embryonic development in lake whitefish (Coregonus clupeaformis)

USGS Publications Warehouse

Brooke, L.T.

1975-01-01

Eggs of lake whitefish (Coregonus clupeaformis) were incubated in a constant-flow incubator at constant temperatures of 0.5, 2.0, 4.0, 5.9, 7.8, and 10.0 C. The time from fertilization to median hatch was inversely related to temperature, and ranged from 41.7 days at 10.0 C to 182 days at 0.5 C. The percentage hatch was highest (70.9-73.3%) at 4.0, 5.9, and 7.8 C, and was greatly reduced (6.0-28.4%) at 0.5, 2.0, and 10.0 C. The mortality of embryos was greatest during the early stages of development. Abnormally developed fry were most frequent (85.9% of the hatch) at 10.0 C, and least frequent (2.8%) at 4.0 C. Mean lengths of fry at hatching were shorter at 7.8 and 10.0 C (12.4 and 8.8 mm, respectively) than at lower temperatures (13.1 to 13.5 mm). The optimum temperature range for incubation of lake whitefish eggs was 3.2 to 8.1 C. Equations were derived for predicting development time to 20 successive stages, and to hatching, at constant incubation temperatures and at fluctuating daily mean water temperatures.

Effect of feeding low-fiber fraction of air-classified sunflower (Helianthus annus L.) meal on laying hen productive performance and egg yolk cholesterol.

PubMed

Laudadio, V; Ceci, E; Lastella, N M B; Tufarelli, V

2014-11-01

The present study was designed to determine the effect on laying performance and egg quality resulting from total substitution of soybean meal (SBM) with low-fiber sunflower meal (SFM; Helianthus annus L.) meal in diet of hens. ISA Brown layers, 28 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were kept in a free-range environment and fed 2 wheat middling-based diets consisting of a control diet, which contained SBM (153 g/kg of diet), and a test diet containing low-fiber SFM (160 g/kg of diet) as the main protein source. Each dietary treatment was replicated 4 times. Low-fiber SFM was obtained by a combination of sieving and air classification processes. Feed consumption was recorded daily and egg production was calculated on a hen-day basis; eggs from each group were collected weekly to evaluate egg components and quality. The total substitution of SBM with low-fiber SFM had no adverse effect on growth performance of laying hens. Egg production and none of egg quality traits examined were influenced by dietary treatment, except for yolk color (P < 0.05) and percentage of large-size eggs (P < 0.05) that were improved in hens fed the low-fiber SFM diet. Including low-fiber SFM decreased serum and egg yolk total cholesterol and low-density lipoprotein cholesterol concentrations (P < 0.001), and increased high-density lipoprotein cholesterol level. Our results suggest that the replacement of conventional soybean with low-fiber sunflower meal may be a valid alternative in diets for laying hens to improve egg quality and to develop low-cholesterol eggs. ©2014 Poultry Science Association Inc.

Embryo developmental events and the egg case of the Aleutian skate Bathyraja aleutica (Gilbert) and the Alaska skate Bathyraja parmifera (Bean).

PubMed

Hoff, G R

2009-02-01

Embryo development events were correlated with egg-case changes for the Aleutian skate Bathyraja aleutica and the Alaska skate Bathyraja parmifera. Yolk absorption underwent two phases: that of steady absorption during early development and that of rapid yolk absorption during the final development stages. Total length (L(T)) for 50% of the pre-hatching embryos egg-case jelly disappearance was 92.04 mm (range 81-102 mm) and 99.36 mm (range 81-100 mm) for B. aleutica and B. parmifera, respectively, allowing the inner chamber to open to seawater flow. The tail filament underwent three phases of growth: rapid elongation during early development (<100 mm embryo L(T)), stasis of tail filament length during the remainder of embryo development and rapid absorption soon after hatching. Complete tail filament development coincided with the disappearance of egg-case jelly. Clasper buds first developed at embryos >70 mm L(T) for both species and the sex ratio was 1:1 well before hatching. Egg cases that were devoid of an ova or developing embryo were c. 5.0 and 6.5% of the egg cases examined for B. aleutica and B. parmifera, respectively. Measurements showed that egg cases containing only egg jelly were smaller in both width and length than those possessing an ova. Embryo stages were punctuated with distinct events that correlated with egg case changes controlling the internal environment of the developing embryo.

Culture of chicken embryo in interspecific surrogate egg white.

PubMed

Liu, C; Zu, J; Baskar, V; Wernery, U; Chang, I K

2012-11-01

The effect of interspecific egg white on the development of chicken embryos was investigated in a surrogate eggshell culture system. Egg yolks were separated from fertile White Leghorn chicken eggs and cultured in different egg whites from turkey (group TK), guineafowl (group GF), and duck (group DK), and chicken (group CK) was used as control. The viability of chicken embryos in groups CK, TK, GF, and DK after 3 d culture in system II was 98.3, 90.2, 96.1, and 91.1%. The whole contents (egg yolk and surrogate egg white) were further transferred into an eggshell from a 1.5 times heavier chicken egg with air space (system III), and incubated for further 16 d, before moving them to a hatcher. No significant difference between the 4 groups was found in their viabilities, which ranged between 72.9 and 81.3%, until 14 d postincubation (P > 0.05). After 21 d, the viability decreased to 60.4, 57.4, 50.0, and 27.7% in groups CK, TK, GF, and DK. The viability in group DK was significantly lower than in the other groups (P < 0.05). Weight loss in system III was approximately 12% in all the 4 groups without significant difference (P > 0.05). Hatchability of the chicken embryo was 60.4, 55.3, 47.9, and 19.1% in groups CK, TK, GF, and DK, respectively, and that in group DK was significantly lower than in the other groups (P < 0.05). There was no difference between the other groups (P > 0.05). These results show that chicken embryos can develop to hatch in duck, guineafowl, and turkey egg whites. However, the hatchability decreases according to the phylogenetic distance. The present study will provide a tool for manipulation of avian embryos and eventual conservation of endangered wild birds.

Effect of egg ingestion on trimethylamine-N-oxide production in humans: a randomized, controlled, dose-response study1234

PubMed Central

Miller, Carolyn A; Corbin, Karen D; da Costa, Kerry-Ann; Zhang, Shucha; Zhao, Xueqing; Galanko, Joseph A; Blevins, Tondra; Bennett, Brian J; O'Connor, Annalouise; Zeisel, Steven H

2014-01-01

Background: It is important to understand whether eating eggs, which are a major source of dietary choline, results in increased exposure to trimethylamine-N-oxide (TMAO), which is purported to be a risk factor for developing heart disease. Objective: We determined whether humans eating eggs generate TMAO and, if so, whether there is an associated increase in a marker for inflammation [ie, high-sensitivity C-reactive protein (hsCRP)] or increased oxidation of low-density lipoprotein (LDL). Design: In a longitudinal, double-blind, randomized dietary intervention, 6 volunteers were fed breakfast doses of 0, 1, 2, 4, or 6 egg yolks. Diets were otherwise controlled on the day before and day of each egg dose with a standardized low-choline menu. Plasma TMAO at timed intervals (immediately before and 1, 2, 4, 8, and 24 h after each dose), 24-h urine TMAO, predose and 24-h postdose serum hsCRP, and plasma oxidized LDL were measured. Volunteers received all 5 doses with each dose separated by >2-wk washout periods. Results: The consumption of eggs was associated with increased plasma and urine TMAO concentrations (P < 0.01), with ∼14% of the total choline in eggs having been converted to TMAO. There was considerable variation between individuals in the TMAO response. There was no difference in hsCRP or oxidized LDL concentrations after egg doses. Conclusions: The consumption of ≥2 eggs results in an increased formation of TMAO. Choline is an essential nutrient that is required for normal human liver and muscle functions and important for normal fetal development. Additional study is needed to both confirm the association between TMAO and atherosclerosis and identify factors, microbiota and genetic, that influence the generation of TMAO before policy and medical recommendations are made that suggest reduced dietary choline intake. This trial was registered at clinicaltrials.gov as NCT01906554. PMID:24944063

Pre-implantation diagnosis of aneuploidy by polar body and blastomere FISH analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munne, S.; Cohen, J.; Grifo, J.

1994-09-01

For preimplantation genetic diagnosis (PGD) of aneuploidy in human in-vitro fertilization (IVF), two blastomeres per embryo should be analyzed to minimize errors caused by FISH and mosaicism. But the biopsy of two cells from an 8-cell embryo can be detrimental. This can be substituted by initial FISH analysis of the first polar body (PB) and subsequent single blastomere analysis. Simultaneous FISH analysis of chromosomes X, Y, 18, 13/21 was used for first polar body aneuploidy analysis. Normal divalents appeared as single-dotted signals corresponding to their two chromatids. We found that pre-division of chromatids increased dramatically with time in culture. Allmore » but three pre-division events involved separation of chromatids within the PB or the egg, with a total of two chromatids in each. We concluded that PB aneuploidy analysis is safe when performed within 6 hours after egg retrieval. For our first clinical case we chose a 39 year-old female carrier of an X-linked disease already selected for FISH pre-implantation diagnosis. Eight polar bodies from 12 eggs were analyzed: six showed a normal X181321 complement of divalents; one had an extra chromatid for 13/21 (egg {number_sign}8); and one had a missing chromatid for 13/21 (egg {number_sign}10). After insemination, six fertilized eggs developed into embryos, including egg {number_sign}10 but not egg {number_sign}8. At day 3 of development, a single blastomere per embryo was analyzed by FISH. According to the blastomere analysis, one embryo was haploid, one tetraploid. The two normal female embryos were replaced and pregnancy and CFS results are pending. These results suggest that this technique can be successfully applied for PGD of major aneuploidies in IVF patients over 35. In addition, it indicates that studies on pre-division should be performed on eggs within six hours of retrieval.« less

Development and reproductive potential of Tyrophagus putrescentiae (Acari: Acaridae) on plant-parasitic nematodes and artificial diets.

PubMed

Abou El-Atta, Doaa Abd El-Maksoud; Osman, Mohamed Ali

2016-04-01

This study investigated development, reproduction and life table parameters of the astigmatid mold mite Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) feeding on egg-masses or adult females of the nematode Meloidogyne incognita, egg-masses of the nematode Rotylenchulus reniformis, ras cheese or yeast at 25 ± 1 °C, 70 ± 10 % RH in the dark. Immature developmental times were shorter when the mite was fed females of M. incognita followed by yeast. Different prey/diet types had no significant effect on longevity and lifespan of both males and females. Daily oviposition rate (eggs/female/day) was highest for mites fed yeast (20.8 ± 1.8 eggs) and lowest for mites fed females of M. incognita (6.6 ± 0.5). Intrinsic rate of natural increase (r m) was highest for mites fed yeast compared to other prey/diet; no significant differences in r m were observed among mites fed on non-yeast diets. This result may suggest a role of T. putrescentiae as biocontrol agent of plant-parasitic nematodes and the yeast may be used for mite mass-production purposes.

Numerical modeling of heat transfer and pasteurizing value during thermal processing of intact egg.

PubMed

Abbasnezhad, Behzad; Hamdami, Nasser; Monteau, Jean-Yves; Vatankhah, Hamed

2016-01-01

Thermal Pasteurization of Eggs, as a widely used nutritive food, has been simulated. A three-dimensional numerical model, computational fluid dynamics codes of heat transfer equations using heat natural convection, and conduction mechanisms, based on finite element method, was developed to study the effect of air cell size and eggshell thickness. The model, confirmed by comparing experimental and numerical results, was able to predict the temperature profiles, the slowest heating zone, and the required heating time during pasteurization of intact eggs. The results showed that the air cell acted as a heat insulator. Increasing the air cell volume resulted in decreasing of the heat transfer rate, and the increasing the required time of pasteurization (up to 14%). The findings show that the effect on thermal pasteurization of the eggshell thickness was not considerable in comparison to the air cell volume.

Quail Egg compared to a quarter

NASA Technical Reports Server (NTRS)

2003-01-01

Quail eggs are small (shown here with a quarter for scale) and develop quickly, making them ideal for space experiments. The Avian Development Facility (ADF) supports 36 eggs in two carousels (below), one of which rotates to provide a 1-g control for comparing to eggs grown in microgravity. The ADF originated in NASA's Shuttle Student Involvement program in the 1980s and was developed under the NASA Small Business Irnovation Research program. In late 2001, the ADF made its first flight and carried eggs used in two investigations, Development and function of the inner-ear balance system in normal and altered gravity environments, and Skeletal development in embryonic quail.

Immunoglobulins in the eggs of the nurse shark, Ginglymostoma cirratum.

PubMed

Haines, Ashley N; Flajnik, Martin F; Rumfelt, Lynn L; Wourms, John P

2005-01-01

Elasmobranchs, which include the sharks, skates, and rays, emerged over 450 million years ago and are the oldest vertebrates to possess an adaptive immune system. They have evolved diverse reproductive modes, with a variety of physiological adaptations that enhance reproductive success. The nurse shark, Ginglymostoma cirratum, is an aplacental, viviparous elasmobranch in which the egg and its associated vitelline vasculature are the primary route for maternal-embryonic interactions. During gestation, nurse shark embryos hatch from their eggcases and develop free in the uterus, which is flushed regularly with seawater. Similar to higher vertebrates, embryonic and neonatal nurse sharks possess an immune system that is not fully competent. In birds and bony fishes, maternal immunoglobulins (Ig) stored in the egg during oogenesis confer protective immunity to embryos during gestation. However, early research suggested that such transfer of passive immunity does not occur in sharks. To better understand how elasmobranch embryos are protected from waterborne pathogens during this potentially vulnerable time, we have re-examined the existence of Igs in elasmobranch eggs. Using monoclonal antibodies, we establish the presence of two classes of Igs in nurse shark eggs: 7S IgM and IgNAR. The potential transfer of immunoglobulins from elasmobranch eggs is discussed.

Avian Incubation Patterns Reflect Temporal Changes in Developing Clutches

PubMed Central

2013-01-01

Incubation conditions for eggs influence offspring quality and reproductive success. One way in which parents regulate brooding conditions is by balancing the thermal requirements of embryos with time spent away from the nest for self-maintenance. Age related changes in embryo thermal tolerance would thus be expected to shape parental incubation behavior. We use data from unmanipulated Black-capped Chickadee (Poecile atricapillus) nests to examine the temporal dynamics of incubation, testing the prediction that increased heat flux from eggs as embryos age influences female incubation behavior and/or physiology to minimize temperature fluctuations. We found that the rate of heat loss from eggs increased with embryo age. Females responded to increased egg cooling rates by altering incubation rhythms (more frequent, shorter on- and off- bouts), but not brood patch temperature. Consequently, as embryos aged, females were able to increase mean egg temperature and decrease variation in temperature. Our findings highlight the need to view full incubation as more than a static rhythm; rather, it is a temporally dynamic and finely adjustable parental behavior. Furthermore, from a methodological perspective, intra- and inter-specific comparisons of incubation rhythms and average egg temperatures should control for the stage of incubation. PMID:23840339

Role of shell diffusion area in incubating eggs at simulated high altitude.

PubMed

Weiss, H S

1978-10-01

Embryonic development is inhibited when eggs are incubated at 9,100 m (0.3 atm) despite a normoxic environment. The problem apparently relates to respiratory gas exchange occurring by diffusion through gas-filled pores in the shell. Gaseous flux is therefore inversely proportional to ambient pressure and is affected by the physical characteristics of the ambient gas (Chapman-Enskog equation). Excess loss of H2O and CO2 occurs in eggs incubating at altitude and could be detrimental. Such increased loss should be correctable by decreasing diffusion area. This was tested by progressively increasing coverage of the shell with paraffin and incubating at simulated 0.3 ATA (225 Torr) in 100% O2. Uncoated eggs failed to hatch, but numbers of chicks increased with increased coverage. Maximum hatch was an extrapolated 90% of controls at 69% shell coverage. With further coverage, hatch size decreased. Egg weight loss, and estimate of H2O diffusion, was around three times controls in uncoated eggs but decreased linearly with paraffin coverage, reaching near normal at maximum hatch. Reduction of diffusion area to 0.3 normal at maximum hatch generally balanced the increased flux predicted for 0.3 ATA.

Comparative proteome analysis of egg yolk plasma proteins during storage.

PubMed

Gao, Dan; Qiu, Ning; Liu, Yaping; Ma, Meihu

2017-06-01

Physical changes such as chicken egg white thinning and egg yolk flattening occur during storage, implying a decline in egg quality. To reveal the deteriorative process related to chicken egg internal quality, a comparative proteomic method was used in this study to analyze the alterations in egg yolk plasma proteins at different storage times (0, 20 and 40 days) under an ambient temperature of 22 ± 2 °C. Using two-dimensional electrophoresis followed by matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry, 33 protein spots representing 12 proteins were identified with significant (P < 0.05) alterations in abundance at different storage times. The proteins that showed significant changes in abundance included serum albumin, vitellogenin fragments, IgY chains, ovalbumin, ovoinhibitor, α 2 -macroglobulin-like protein 1-like, hemopexin, transthyretin, apolipoprotein A-I and β 2 -glycoprotein I precursor. Accelerating degradation for most egg yolk plasma proteins was observed after prolonged storage (from day 20 to day 40). It is likely that the increased degradation of protease inhibitors such as ovoinhibitor and α 2 -macroglobulin-like protein 1-like during prolonged storage lead to an imbalance of protease and antiprotease in egg yolk, which may play a key role in the degradation of egg yolk proteins. These findings will provide an insight into the effects of storage on egg yolk protein changes and give a deeper understanding of the deteriorative process of chicken egg yolk. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Brood parasitism selects for no defence in a cuckoo host.

PubMed

Krüger, Oliver

2011-09-22

In coevolutionary arms races, like between cuckoos and their hosts, it is easy to understand why the host is under selection favouring anti-parasitism behaviour, such as egg rejection, which can lead to parasites evolving remarkable adaptations to 'trick' their host, such as mimetic eggs. But what about cases where the cuckoo egg is not mimetic and where the host does not act against it? Classically, such apparently non-adaptive behaviour is put down to evolutionary lag: given enough time, egg mimicry and parasite avoidance strategies will evolve. An alternative is that absence of egg mimicry and of anti-parasite behaviour is stable. Such stability is at first sight highly paradoxical. I show, using both field and experimental data to parametrize a simulation model, that the absence of defence behaviour by Cape bulbuls (Pycnonotus capensis) against parasitic eggs of the Jacobin cuckoo (Clamator jacobinus) is optimal behaviour. The cuckoo has evolved massive eggs (double the size of bulbul eggs) with thick shells, making it very hard or impossible for the host to eject the cuckoo egg. The host could still avoid brood parasitism by nest desertion. However, higher predation and parasitism risks later in the season makes desertion more costly than accepting the cuckoo egg, a strategy aided by the fact that many cuckoo eggs are incorrectly timed, so do not hatch in time and hence do not reduce host fitness to zero. Selection will therefore prevent the continuation of any coevolutionary arms race. Non-mimetic eggs and absence of defence strategies against cuckoo eggs will be the stable, if at first sight paradoxical, result. This journal is © 2011 The Royal Society

Nutrient Content of Brown Marmorated Stink Bug Eggs and Comparisons Between Experimental Uses

PubMed Central

Skillman, Victoria P

2017-01-01

Abstract Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), the brown marmorated stink bug (BMSB), has become a major pest. Seven experiments examined the nutrient content of their eggs in the context of female reproductive investment and use for experiments. Among 542 clusters examined, an average egg contained 23.50 ± 0.561 µg lipid, 3.17 ± 0.089 µg glycogen, and 3.08 ± 0.056 µg sugar. Mature eggs within a female’s ovary can make up 61% of her total lipid, 35% of glycogen, and 20% of sugar levels. Eggs obtained from a colony reared on a steady diet are expected to have consistent nutrient content. The age of a parental female only slightly affected the lipid level of oviposited eggs but did not affect glycogen or sugar levels. However, egg nutrient content can differ substantially by the source of the parental females; wild eggs had higher lipid but lower sugar content than colony-produced eggs. Further, the length of time that eggs are frozen influenced egg nutrient content. Freshly laid eggs had higher lipid and lower sugar levels than eggs frozen for 1 or 2 yr. Whether an egg turned grey following removal from cold storage did not affect nutrient content, nor did being frozen within 1 or 3 d of oviposition. The temperature at which eggs were left exposed did not impact egg nutrient content, but glycogen decreased and sugar increased with deployment time. This information combined with how factors affect host selection by natural enemies will help refine future experiments that use BMSB egg clusters.

Confirmation of cisco spawning in Chaumont Bay, Lake Ontario using an egg pumping device

USGS Publications Warehouse

George, Ellen M.; Stott, Wendylee; Young, Brian; Karboski, Curtis T.; Crabtree, Darran L.; Roseman, Edward; Rudstam, Lars G.

2017-01-01

Cisco Coregonus artedi, a historically abundant and commercially important fish in the Great Lakes, have declined drastically in the last century due to the impacts of invasive species, overfishing, and habitat degradation. Chaumont Bay, New York is believed to contain one of the last remaining spawning populations of cisco in Lake Ontario although direct evidence of spawning has remained elusive. We document cisco spawning in Chaumont Bay for the first time in decades through the use of an egg pumping device specifically developed to sample through lake ice. Forty-one eggs were identified as cisco using genetic barcoding of the mitochondrial cytochrome c oxidase I (COI) gene. Cisco eggs were associated with shallow, rocky shoals. Contemporary knowledge of spawning behavior is an important step toward the successful restoration of cisco in Lake Ontario and across the Great Lakes.

Geographic variation in cannibalism in Colorado potato beetle (Coleoptera: Chrysomelidae) populations.

PubMed

Baker, Mitchell; Hossain, Kazi; Zabierek, Kristina; Collie, Karyn; Alyokhin, Andrei; Mota-Sanchez, David; Whalon, Mark

2014-02-01

Cannibalism can have a large effect on population growth and survival in stressful environments, possibly including those created by insecticide use. In this study, we collected Colorado potato beetles from three isolated areas in the northeastern United States known for high levels of resistance to neonicotinoids. We measured resistance to imidacloprid in each of those populations, a laboratory susceptible population, and in hybrids between the three field populations and the laboratory susceptible population. We fed neonates eggs from resistant dams fed either imidacloprid-treated or untreated foliage to determine whether cannibals are exposed to toxins sequestered in eggs. We measured egg cannibalism by hatchlings within the clutch in each population and hybrids, and examined how fecundity and several variables associated with egg development varied among populations and with cannibalism, to see which traits might enhance or reduce cannibalism. Cannibalism varied significantly among populations, accounting for most of the variation in hatching success. Variability in egg development time and hatch rate in the absence of cannibalism in some populations affected rates of cannibalism. Resistance varied significantly among the field populations but was not related to cannibalism. Neonates fed eggs from dams on treated foliage showed signs of intoxication or death. Cannibalism appears to be part of a varying life history strategy in this species, with some populations laying larger and more cannibalistic clutches and the New York population laying smaller clutches with higher hatching success owing to reduced cannibalism.

In an Egg Shell: Egg to Chick to Egg.

ERIC Educational Resources Information Center

Lyon Electric Company, Chula Vista, CA.

The goals of this program include enabling students to learn about the anatomy of an avian egg, egg formation, bird embryo development, and the process of egg incubation. This guide is designed to accompany the hands-on experience of incubation and hatching chicken eggs and is organized in three sections. The teaching materials section includes…

Heat resistance of Salmonella in various egg products.

PubMed

Garibaldi, J A; Straka, R P; Ijichi, K

1969-04-01

The heat-resistance characteristics of Salmonella typhimurium Tm-1, a reference strain in the stationary phase of growth, were determined at several temperatures in the major types of products produced by the egg industry. The time required to kill 90% of the population (D value) at a given temperature in specific egg products was as follows: at 60 C (140 F), D = 0.27 min for whole egg; D = 0.60 min for whole egg plus 10% sucrose; D = 1.0 min for fortified whole egg; D = 0.20 min for egg white (pH 7.3), stabilized with aluminum; D = 0.40 min for egg yolk; D = 4.0 min for egg yolk plus 10% sucrose; D = 5.1 min for egg yolk plus 10% NaCl; D = 1.0 min for scrambled egg mix; at 55 C (131 F), D = 0.55 min for egg white (pH 9.2); D = 1.2 min for egg white (pH 9.2) plus 10% sucrose. The average Z value (number of degrees, either centigrade or fahrenheit, for a thermal destruction time curve to traverse one logarithmic cycle) was 4.6 C (8.3 F) with a range from 4.2 to 5.3 C. Supplementation with 10% sucrose appeared to have a severalfold greater effect on the heat stabilization of egg white proteins than on S. typhimurium Tm-1. This information should be of value in the formulation of heat treatments to insure that all egg products be free of viable salmonellae.

Longevity and viability of Taenia solium eggs in the digestive system of the beetle Ammophorus rubripes.

PubMed

Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano

2014-03-01

The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle's digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas.

LONGEVITY AND VIABILITY OF Taenia solium EGGS IN THE DIGESTIVE SYSTEM OF THE BEETLE Ammophorus rubripes

PubMed Central

Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano

2015-01-01

The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viability of eggs in their digestive system. One hundred beetles were distributed into five polyethylene boxes, and then they were infected with T. solium eggs. Gravid proglottids of T. solium were crushed and then mixed with cattle feces. One gram of this mixture was placed in each box for 24 hours, after which each group of beetles was transferred into a new clean box. Then, five beetles were dissected every three days. Time was strongly associated with viability (r=0.89; P<0.001) and the calculated time to cero viability is 36 days. The eggs in the intestinal system of each beetle were counted and tested for viability. Taenia solium eggs were present in the beetle’s digestive system for up to 39 days (13th sampling day out of 20), gradually reducing in numbers and viability, which was 0 on day 36 post-infection. Egg viability was around 40% up to day 24 post-infection, with a median number of eggs of 11 per beetle at this time. Dung beetles may potentially contribute towards dispersing T. solium eggs in endemic areas. PMID:24728368

Quantitative Aspects of the Development of Meloidogyne arenaria Larvae in Grapevine Varieties and Rootstocks.

PubMed

Ferris, H; Hunt, W A

1979-04-01

The development and productivity of parasitic stages of Meloidogyne arenaria were quantitatively defined in 14 varieties or rootstocks of grapevine. Mean development to maturity was related linearly to the number of degree-hours above 10 C temperature experienced from the time of penetration in all cultivars in which nematode adulthood was achieved. Averaged across varieties, 13,142 heat units were required for development of the mean individual to maturity. The standard deviation of the developing individuals about the mean, expressed as a proportion with 1 representing adulthood, did not differ with time or among varieties after 7,000 degree-hours had elapsed. Earliest egg production was observed after 7,662 degree-hours, averaged across varieties, considerably before mean development to maturity. Varieties were also ranked relative to the number of larvae establishing infection sites, and the rate of egg production per adult female. Varieties could he grouped according to their levels of horizontal resistance.

Vitellogenin knockdown strongly affects cotton boll weevil egg viability but not the number of eggs laid by females.

PubMed

Coelho, Roberta R; de Souza Júnior, José Dijair Antonino; Firmino, Alexandre A P; de Macedo, Leonardo L P; Fonseca, Fernando C A; Terra, Walter R; Engler, Gilbert; de Almeida Engler, Janice; da Silva, Maria Cristina M; Grossi-de-Sa, Maria Fatima

2016-09-01

Vitellogenin (Vg), a yolk protein precursor, is the primary egg nutrient source involved in insect reproduction and embryo development. The Cotton Boll weevil (CBW) Anthonomus grandis Boheman, the most important cotton pest in Americas, accumulates large amounts of Vg during reproduction. However, the precise role of this protein during embryo development in this insect remains unknown. Herein, we investigated the effects of vitellogenin (AgraVg) knockdown on the egg-laying and egg viability in A. grandis females, and also characterized morphologically the unviable eggs. AgraVg transcripts were found during all developmental stages of A. grandis, with highest abundance in females. Silencing of AgraVg culminated in a significant reduction in transcript amount, around 90%. Despite this transcriptional reduction, egg-laying was not affected in dsRNA-treated females but almost 100% of the eggs lost their viability. Eggs from dsRNA-treated females showed aberrant embryos phenotype suggesting interference at different stages of embryonic development. Unlike for other insects, the AgraVg knockdown did not affect the egg-laying ability of A. grandis, but hampered A. grandis reproduction by perturbing embryo development. We concluded that the Vg protein is essential for A. grandis reproduction and a good candidate to bio-engineer the resistance against this devastating cotton pest.

Changes during late-stage embryonic development from egg-juvenile to free-living hatchling in Chinese freshwater crab Sinopotamon yangtsekiense (Decapoda, Brachyura, Potamidae)

NASA Astrophysics Data System (ADS)

Xue, Junzeng; Liu, Yan; Cumberlidge, Neil; Wu, Huixian

2013-05-01

This study expands on recent reports that direct development in the Chinese potamid freshwater crab Sinopotamon yangtsekiense involves the completion of all brachyuran larval stages (nauplius, zoea, and megalopa) inside the egg case during embryonic development. Detailed studies of embryonic development in this species revealed the presence of an additional larval stage (the egg-juvenile) between the megalopa and the free-living hatchling crab. We described and compared the appendages of the head, thorax, and abdomen of the egg-juvenile with those of the hatchling crab in S. yangtsekiense. Significant differences were found between most of the appendages of these two stages with a soft exoskeleton in the egg-juvenile, no joint articulation, a slimmer appearance, and a lack of setae when compared with the newly emerged free-living hatchling crab. These modifications of the appendages are related to the confinement within the egg case of the egg-megalopa and egg-juvenile during direct development, and the need for the free-living hatchling freshwater crab to move, feed, and respire. In marine crabs, the megalopa gives rise to the first crab stage whereas in freshwater crabs the egg-juvenile follows the megalopa and immediately precedes the free-living first crab stage.

The Genetic Basis of Natural Variation in Drosophila (Diptera: Drosophilidae) Virgin Egg Retention

PubMed Central

Akhund-Zade, Jamilla; Bergland, Alan O.; Crowe, Sarah O.; Unckless, Robert L.

2017-01-01

Drosophila melanogaster is able to thrive in harsh northern climates through adaptations in life-history traits and physiological mechanisms that allow for survival through the winter. We examined the genetic basis of natural variation in one such trait, female virgin egg retention, which was previously shown to vary clinally and seasonally. To further our understanding of the genetic basis and evolution of virgin egg retention, we performed a genome-wide association study (GWAS) using the previously sequenced Drosophila Genetic Reference Panel (DGRP) mapping population. We found 29 single nucleotide polymorphisms (SNPs) associated with virgin egg retention and assayed 6 available mutant lines, each harboring a mutation in a candidate gene, for effects on egg retention time. We found that four out of the six mutant lines had defects in egg retention time as compared with the respective controls: mun, T48, Mes-4, and Klp67A. Surprisingly, none of these genes has a recognized role in ovulation control, but three of the four genes have known effects on fertility or have high expression in the ovaries. We also found that the SNP set associated with egg retention time was enriched for clinal SNPs. The majority of clinal SNPs had alleles associated with longer egg retention present at higher frequencies in higher latitudes. Our results support previous studies that show higher frequency of long retention times at higher latitude, providing evidence for the adaptive value of virgin egg-retention. PMID:28042107

Heat Stress Impedes Development and Lowers Fecundity of the Brown Planthopper Nilaparvata lugens (Stål)

PubMed Central

Piyaphongkul, Jiranan; Pritchard, Jeremy; Bale, Jeff

2012-01-01

This study investigated the effects of sub-lethal high temperatures on the development and reproduction of the brown plant hopper Nilaparvata lugens (Stål). When first instar nymphs were exposed at their ULT50 (41.8°C) mean development time to adult was increased in both males and females, from 15.2±0.3 and 18.2±0.3 days respectively in the control to 18.7±0.2 and 19±0.2 days in the treated insects. These differences in development arising from heat stress experienced in the first instar nymph did not persist into the adult stage (adult longevity of 23.5±1.1 and 24.4±1.1 days for treated males and females compared with 25.7±1.0 and 20.6±1.1 days in the control groups), although untreated males lived longer than untreated females. Total mean longevity was increased from 38.8±0.1 to 43.4±1.0 days in treated females, but male longevity was not affected (40.9±0.9 and 42.2±1.1 days respectively). When male and female first instar nymphs were exposed at their ULT50 of 41.8°C and allowed to mate on reaching adult, mean fecundity was reduced from 403.8±13.7 to 128.0±16.6 eggs per female in the treated insects. Following exposure of adult insects at their equivalent ULT50 (42.5°C), the three mating combinations of treated male x treated female, treated male x untreated female, and untreated male x treated female produced 169.3±14.7, 249.6±21.3 and 233.4±17.2 eggs per female respectively, all significantly lower than the control. Exposure of nymphs and adults at their respective ULT50 temperatures also significantly extended the time required for their progeny to complete egg development for all mating combinations compared with control. Overall, sub-lethal heat stress inhibited nymphal development, lowered fecundity and extended egg development time. PMID:23071803

Patterns and Drivers of Egg Pigment Intensity and Colour Diversity in the Ocean: A Meta-Analysis of Phylum Echinodermata.

PubMed

Montgomery, E M; Hamel, J-F; Mercier, A

Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is supported by the comparatively pale colour of equally large, internally brooded eggs. Secondarily, geographic location drives the evolution of egg colour diversity, presumably through the selection of better-adapted, more costly pigments in response to ecological pressure. © 2017 Elsevier Ltd. All rights reserved.

The relationship of parthenogenesis in virgin Chinese Painted quail (Coturnix chinensis) hens with embryonic mortality and hatchability following mating.

PubMed

Parker, H M; Kiess, A S; Robertson, M L; Wells, J B; McDaniel, C D

2012-06-01

Unfertilized chicken, turkey, and quail eggs are capable of developing embryos by parthenogenesis. However, it is unknown if the physiological mechanisms regulating parthenogenesis in virgin hens may actually work against fertilization, embryonic development, and hatchability of eggs from these same hens following mating. Additionally, because most parthenogenic development closely resembles early embryonic mortality in fertilized eggs during the first 2 to 3 d of incubation, it is possible that many unhatched eggs classified as containing early embryonic mortality may actually be unfertilized eggs that contain parthenogens. Therefore, the objective of this study was to examine the relationship of parthenogenesis before mating with embryonic development and hatchability characteristics after mating. Based upon their ability to produce unfertilized eggs that contain parthenogens, 372 virgin Chinese Painted quail hens were divided into 7 groups, according to their incidence of parthenogenesis: 0, 10, 20, 30, 40, 50, and greater than 50% parthenogenesis. Males were then placed with these hens so that fertility, embryonic mortality, and hatchability could be evaluated for each hen. Hatchability of eggs set, hatchability of fertile eggs, and late embryonic mortality declined dramatically as the incidence of parthenogenesis increased. On the other hand, early embryonic mortality increased as parthenogenesis increased. Fertility was not different across the 7 parthenogenesis hen groups, perhaps because unfertilized eggs that exhibited parthenogenesis resembled and were therefore classified as early embryonic mortality. In conclusion, virgin quail hens that exhibit parthenogenesis appear to have impaired embryonic development and hatchability following mating. Additional sperm-egg interaction and embryonic research is needed to determine if a large portion of the early embryonic mortality experienced by mated hens that exhibit parthenogenesis as virgin hens is in fact embryonic development in unfertilized eggs.

IL-10R Blockade during Chronic Schistosomiasis Mansoni Results in the Loss of B Cells from the Liver and the Development of Severe Pulmonary Disease

PubMed Central

Fairfax, Keke C.; Amiel, Eyal; King, Irah L.; Freitas, Tori C.; Mohrs, Markus; Pearce, Edward J.

2012-01-01

In schistosomiasis patients, parasite eggs trapped in hepatic sinusoids become foci for CD4+ T cell-orchestrated granulomatous cellular infiltrates. Since the immune response is unable to clear the infection, the liver is subjected to ongoing cycles of focal inflammation and healing that lead to vascular obstruction and tissue fibrosis. This is mitigated by regulatory mechanisms that develop over time and which minimize the inflammatory response to newly deposited eggs. Exploring changes in the hepatic inflammatory infiltrate over time in infected mice, we found an accumulation of schistosome egg antigen-specific IgG1-secreting plasma cells during chronic infection. This population was significantly diminished by blockade of the receptor for IL-10, a cytokine implicated in plasma cell development. Strikingly, IL-10R blockade precipitated the development of portal hypertension and the accumulation of parasite eggs in the lungs and heart. This did not reflect more aggressive Th2 cell responsiveness, increased hepatic fibrosis, or the emergence of Th1 or Th17 responses. Rather, a role for antibody in the prevention of severe disease was suggested by the finding that pulmonary involvement was also apparent in mice unable to secrete class switched antibody. A major effect of anti-IL-10R treatment was the loss of a myeloid population that stained positively for surface IgG1, and which exhibited characteristics of regulatory/anti-inflammatory macrophages. This finding suggests that antibody may promote protective effects within the liver through local interactions with macrophages. In summary, our data describe a role for IL-10-dependent B cell responses in the regulation of tissue damage during a chronic helminth infection. PMID:22291593

Characteristics and incidence of large eggs in Trichuris muris.

PubMed

Koyama, Koichi

2013-05-01

The production of small numbers of large eggs among the standard-sized eggs of Trichuris trichiura is well known. Large eggs have also been observed in Trichuris muris, but they have not been studied previously. This paper compares the characteristics of the large eggs (LEs, ≥74.5 μm long) and standard-sized eggs (SEs, <74.5 μm long) in cultures of T. muris. Among 112,554 cultured eggs, LEs occurred at very low frequency (0.03 %, i.e., about three large eggs per 10(4) cultured eggs). Embryonated eggs represented 93.72 % of SEs, but only 25.00 % of LEs were embryonated. Embryonated LEs and SEs contained fully matured larvae. An atypical category of unembryonated egg, which contained an incompletely developed larva, an abnormal larva, or granular components, was common among the LEs. However, similar atypical unembryonated SEs were rarely observed. These observations suggest that the LEs that occur very infrequently in T. muris result from an abnormality of embryonation (larval development).

Chilling requirements for hatching of a New Zealand isolate of Nematodirus filicollis.

PubMed

Oliver, A-M B; Pomroy, W E; Ganesh, S; Leathwick, D M

2016-08-15

The eggs of some species of the parasitic nematode Nematodirus require a period of chilling before they can hatch; N. filicollis is one such species. This study investigated this requirement for chilling in a New Zealand strain of this species. Eggs of N. filicollis were extracted from lamb's faeces and incubated at 20°C to allow development to the third stage larvae within the egg. These eggs were then placed into tissue culture plates and incubated at: 2.7°C (±0.99), 3.6°C (±0.90), 4.7°C (±0.35), 6.4°C (±0.37), 8.0°C (±1.54) or 9.9°C (±0.14) for up to 224 days. At 14day intervals until day 84, then every 28 days, one plate was removed from each temperature and placed at 13.1°C (±0.44) for 14 days. Eggs were then assessed for hatching. From this data, chill units were calculated by subtracting the culture temperature from a constant threshold of 11°C and multiplying by the number of days for which the sample was cultured; then the Gompertz model fitted. Even though hatching overall was low, a greater proportion of eggs hatched with chill accumulation. Maximum hatching of eggs required 800-1000 chill units. Consequently in the field, more than one season of chilling would be required before hatching. As such a generation time could take more than one year to complete. This is different to the hatching dynamics of N. spathiger, the other main species found in New Zealand sheep, which does not display this requirement for chilling and hatches immediately once the third stage larvae are developed. Copyright © 2016 Elsevier B.V. All rights reserved.

Caffeine alleviates the deterioration of Ca2+ release mechanisms and fragmentation of in vitro aged mouse eggs

PubMed Central

Zhang, Nan; Wakai, Takuya; Fissore, Rafael. A.

2011-01-01

The developmental competence of mammalian eggs is compromised by postovulatory aging. We and others found that in these eggs the intracellular calcium ([Ca2+]i) responses required for egg activation and initiation of development are altered. Nevertheless, the mechanism(s) underlying this defective Ca2+ release is not well known. Here, we investigated if the function of IP3R1, the major Ca2+ release channel at fertilization, was undermined in in vitro aged mouse eggs. We found that in aged eggs IP3R1 displayed reduced function, as many of the changes acquired during maturation that enhance IP3R1 Ca2+ conductivity such as phosphorylation, receptor reorganization and increased Ca2+ store content ([Ca2+]ER) were lost with increasing postovulatory time. IP3R1 fragmentation, possibly associated with the activation of caspase-3, was also observed in these eggs. Many of these changes were prevented when the postovulatory aging of eggs was carried out in the presence of caffeine, which minimized the decline in IP3R1 function and maintained [Ca2+]ER content. Caffeine also maintained mitochondrial membrane potential as measured by JC-1 fluorescence. We therefore conclude that [Ca2+]i responses in aged eggs are undermined by reduced IP3R1 sensitivity, decreased [Ca2+]ER and compromised mitochondrial function, and that addition of caffeine ameliorates most of these aging-associated changes. Understanding the molecular basis of the protective effects of caffeine will be useful in elucidating, and possibly reversing, the signaling pathway(s) compromised by in vitro culture of eggs. PMID:22095868

Radiation of Bactrocera dorsalis (Diptera: Tephritidae) Eggs to Improve the Mass Rearing of Diachasmimorpha longicaudata (Hymenoptera: Braconidae).

PubMed

Cai, Pumo; Hong, Jingfang; Wang, Cong; Yang, Yanchuan; Zhang, Qiwen; Ji, Qinge; Chen, Jiahua

2018-05-28

This study explored the potential for Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) larvae hatched from irradiated eggs as hosts for Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae). B. dorsalis eggs of three different ages (12-, 24-, and 36-h old) were analyzed for hatchability, pupation rate, pupal weight, emergence rate, and sex ratio after exposure to different doses of radiation (5 and 10 Gy) at different dose rates (1 and 6 Gy/min). For the eggs of different ages exposed to radiation, only the hatchability and pupal weight of 36-h-old eggs exposed to the dose rate of 1 Gy/min were not affected; therefore, 6 Gy/min was not suitable for irradiating eggs. The viability of the parents and progenies of D. longicaudata when the parents were reared from 36-h-old eggs irradiated at nine different doses (0, 5, 10, 15, 20, 25, 30, 35, and 40 Gy) under laboratory conditions were investigated. The emergence percentage, sex ratio, and longevity of parasitoids developed from irradiated eggs were similar to those reared from nonirradiated hosts. A significant increase in larva mortality was observed for the eggs irradiated at doses above 25 Gy, and no redundant adult flies emerged at doses above 15 Gy. Hence, for B. dorsalis eggs to be applied in the mass rearing of D. longicaudata, the age of 36 h and a dose of 20-25 Gy are the optimal parameters. The results reveal that hosts and parasitoids need not be separated, enabling a reduction in cost, labor, and time and resulting in an improved mass rearing procedure for D. longicaudata.

Induction of Food Allergy in Mice by Allergen Inhalation

DTIC Science & Technology

2015-10-01

whether and how inhaling egg white can sensitize for the development of egg white food allergy. Despite difficulties related to the complicated pregnancy...and illness of a key researcher, considerable progress has been made: 1) We cannot induce an allergic response to aerosolized egg white, even if...have shown that egg yolk acts as an adjuvant for the development of allergic lung disease tp egg white and induction of food allergy; 3) We have

Comparison of hatching egg characteristics, embryo development, yolk absorption, hatch window, and hatchability of Pekin Duck eggs of different weights.

PubMed

Ipek, A; Sozcu, A

2017-10-01

This study was carried out to determine the hatching egg characteristics, embryo development and yolk absorption during incubation, hatch window, and hatchability of Pekin duck eggs of different weights. A total of 960 hatching eggs was obtained from a breeder flock 35 to 36 wk of age. The eggs were classed into 3 weight categories: "light" (L; <75 g), "medium" (M; 76 to 82 g), and "heavy" (H; >83 g). The albumen weight was the highest in the heavy eggs, whereas the yolk weight was higher in the medium and heavy eggs. Egg breaking strength was the highest with a value of 2.5 kg/cm2 in light eggs, whereas the thinnest eggshell (0.3862 mm) was observed in heavy eggs. pH of albumen and yolk was similar and ranged from 8.8 to 8.9 and 5.9 to 6.0, respectively. On d 14 of incubation, yolk sac weight was found higher in the medium and heavy eggs. Additionally, the dry matter of the embryo and yolk sac differed among the egg weight groups during the incubation period. Interestingly, on d 25 of incubation, the embryo weight was higher in the light and heavy eggs (35.2 and 36.3 g, respectively) than in the medium eggs (29.8 g). These findings showed that embryo growth was affected by yolk absorption and dry matter accumulation. The hatchability of total and fertile eggs was lower for the heavy eggs than the light and medium eggs. The chick weight was 42.8, 48.4, and 54.9 g in light, medium, and heavy eggs, respectively. A percentage of 34.2, 36, and 31.6% of chicks from light, medium, and heavy eggs, hatched between 637 and 648 h, 39.6, 36.2, and 32.9% between 649 and 660 h, 26.2, 27.8, and 35.5% between 661 and 672 h of incubation, respectively. In conclusion, hatching egg quality, embryo development and yolk absorption during incubation, hatch window, and hatchability were affected by egg weight in Pekin ducks. © 2017 Poultry Science Association Inc.

Developmental plasticity in Tenebrio molitor (Coleoptera: Tenebrionidae): Analysis of Instar Variation in Number and Development Time under Different Diets

USDA-ARS?s Scientific Manuscript database

The variation in instar number and the pattern of sequential instar development time of Tenebrio molitor L. (Coleoptera: Tenebrionidae) was studied under 4 different diet regimes. Addition of dietary supplements consisting of dry potato or a mix of dry potato and dry egg whites significantly reduced...

In Vitro Cultivation of Cymatocarpus solearis (Brachycoeliidae) Metacercariae to Obtain the Adult Stage without the Marine Turtle Definitive Host

PubMed Central

Álvarez-Cadena, José

2010-01-01

In vitro cultivation of trematodes would assist studies on the basic biology of the parasites and their hosts. This is the first study to use the yolk of unfertilized chicken eggs as a simple and successful method of ovocultivation and the first time to obtain the adult-stage of the trematode Cymatocarpus solearis Braun, 1899 (Digenea: Brachycoeliidae). Chicken eggs were inoculated with metacercariae from the muscle of the spiny lobster, Panulirus argus (Latreille, 1804). The metacercariae were excysted and incubated for 576 hr (24 days) at 38℃ to obtain the adult stage. Eggs in utero were normal in shape and light brown color. The metacercariae developed into mature parasites that have been identified as the adult-stage found in marine turtles. The adult lobsters collected in Quintana Roo State, Mexico, showed the prevalence of 49.4% and the mean intensity of 26.0 per host (n = 87). A statistical study was performed to determine that no parasitic preference was detected for male versus female parasitized lobsters. Morphometric measurements of the adult-stage of C. solearis obtained in our study have been deposited in the National Helminths Collection of the Institute of Biology of the National Autonomous University of Mexico. This study is significant because it is the first time that a digenean of the family Brachycoeliidae has been demonstrated to develop in vitro from metacercariae into adults capable of producing eggs using the yolk of unfertilized chicken eggs. Secondly, this technique allows to obtain the adult stage of C. solearis without the presence of its marine turtle host, allows us to describe the mature parasites, and thus contribute to our understanding of the biology of C. solearis. PMID:20333285

Adaptive influence of extrinsic and intrinsic factors on variation of incubation periods among tropical and temperate passerines

USGS Publications Warehouse

Martin, Thomas E.; Ton, Riccardo; Oteyza, Juan C.

2018-01-01

Understanding intrinsic (physiological) and extrinsic (e.g., temperature) causes of variation in embryonic development time (incubation period) is important because they can have different impacts on individual quality. Robert Ricklefs and colleagues have argued that longer incubation periods result primarily from intrinsic physiological programs that increase individual quality and adult survival. They claim that incubation periods are largely invariant and that extrinsic factors like temperature have little impact. We have argued that adult survival may be a cause rather than a consequence of much of the variation in embryonic development time. A reduction in extrinsic sources of annual adult mortality (e.g., migration, predation, nonbreeding-season mortality) favors reduced parental effort during incubation to minimize costs to future reproduction and survival. Reduced parental effort, in turn, manifests as cooler average egg temperatures that yield longer incubation periods. Ricklefs and colleagues mischaracterized our hypothesis and deconstructed their own incorrect version, while also making some incorrect statements. We show that reevaluation of previous evidence provided by this group actually supports a role of egg temperature for the variation in incubation periods. We also summarize other observational and experimental evidence that incubation periods are not invariant and that egg temperature has a strong causal influence on variation within and among species. In fact, egg temperature explains ∼60% of the difference in incubation periods among species. The remaining ∼40% reflects intrinsic physiological programs and other factors, potentially providing intrinsic benefits. Ultimately, annual adult mortality explains substantial variation in parental effort and egg temperature, and the latter strongly explains variation in incubation periods. Both intrinsic programs and extrinsic temperature effects need to be considered in attempts to understand incubation strategies.

In vitro cultivation of Cymatocarpus solearis (Brachycoeliidae) metacercariae to obtain the adult stage without the marine turtle definitive host.

PubMed

Grano-Maldonado, Mayra; Alvarez-Cadena, José

2010-03-01

In vitro cultivation of trematodes would assist studies on the basic biology of the parasites and their hosts. This is the first study to use the yolk of unfertilized chicken eggs as a simple and successful method of ovocultivation and the first time to obtain the adult-stage of the trematode Cymatocarpus solearis Braun, 1899 (Digenea: Brachycoeliidae). Chicken eggs were inoculated with metacercariae from the muscle of the spiny lobster, Panulirus argus (Latreille, 1804). The metacercariae were excysted and incubated for 576 hr (24 days) at 38 to obtain the adult stage. Eggs in utero were normal in shape and light brown color. The metacercariae developed into mature parasites that have been identified as the adult-stage found in marine turtles. The adult lobsters collected in Quintana Roo State, Mexico, showed the prevalence of 49.4% and the mean intensity of 26.0 per host (n = 87). A statistical study was performed to determine that no parasitic preference was detected for male versus female parasitized lobsters. Morphometric measurements of the adult-stage of C. solearis obtained in our study have been deposited in the National Helminths Collection of the Institute of Biology of the National Autonomous University of Mexico. This study is significant because it is the first time that a digenean of the family Brachycoeliidae has been demonstrated to develop in vitro from metacercariae into adults capable of producing eggs using the yolk of unfertilized chicken eggs. Secondly, this technique allows to obtain the adult stage of C. solearis without the presence of its marine turtle host, allows us to describe the mature parasites, and thus contribute to our understanding of the biology of C. solearis.

Spatial and temporal variation in efficiency of the Moore egg collector

USGS Publications Warehouse

Worthington, Thomas A.; Brewer, Shannon K.; Farless, Nicole

2013-01-01

The Moore egg collector (MEC) was developed for quantitative and nondestructive capture of semibuoyant fish eggs. Previous studies have indicated that capture efficiency of the MEC was low and the use of one device did not adequately represent the spatial distribution within the water column of egg surrogates (gellan beads) of pelagic broadcast-spawning cyprinids. The objective of this study was to assess whether use of multiple MECs showed differences in spatial and temporal distribution of bead catches. Capture efficiency of three MECs was tested at four 500-m sites on the South Canadian River, a Great Plains river in Oklahoma. For each trial, approximately 100,000 beads were released and mean capture efficiency was 0.47–2.16%. Kolmogorov–Smirnov tests indicated the spatial distributions of bead catches were different among multiple MECs at three of four sites. Temporal variability in timing of peak catches of gellan beads was also evident between MECs. We concluded that the use of multiple MECs is necessary to properly sample eggs of pelagic broadcast-spawning cyprinids.

Producing and marketing a specialty egg.

PubMed

Michella, S M; Slaugh, B T

2000-07-01

Eggland's Best, Inc. markets premium quality shell eggs under the Eggland's Best (EB) brand name. The company, started in 1988, is comprised of a franchise network of established egg producers and covers most of the United States. Eggland's Best provides its franchisees with marketing and technical support. The franchisees produce, process, and distribute EB eggs according to the strict program established and monitored by EB. Production follows the all-natural vegetarian feed program in accordance with the company's US patent entitled "Eggs Compatible with a Cholesterol Reducing Diet and Method of Producing the Same." The EB program excludes animal fat and other animal byproducts. Eggland's Best eggs have seven times the generic level of vitamin E, nearly three times more omega-3 fatty acids and iodine, and 25% less saturated fat than regular generic eggs. Eggland's Best has one of the finest shell egg quality assurance programs anywhere. Eggland's Best franchisees submit weekly egg samples that are analyzed for shell quality, interior quality, vitamin E, iodine, cholesterol and fatty acids. Samples of feed and the EB-patented feed supplement are also analyzed. Approximately 28,000 total laboratory tests are conducted annually. Nationwide product and display retail evaluations are contracted through an outside audit company (40 to 50 cities evaluated four times per year). All EB eggs are USDA graded according to EB's strict quality standards. Producers must follow a food safety quality assurance program (United Egg Producers Association 5-Star or equivalent state or company program). Each egg is stamped "EB" as assurance of meeting EB's highest standards of flavor, quality, and nutrition. Eggland's Best has enjoyed record sales growth for the past 3 yr.

Improvement of sampling plans for Salmonella detection in pooled table eggs by use of real-time PCR.

PubMed

Pasquali, Frédérique; De Cesare, Alessandra; Valero, Antonio; Olsen, John Emerdhal; Manfreda, Gerardo

2014-08-01

Eggs and egg products have been described as the most critical food vehicles of salmonellosis. The prevalence and level of contamination of Salmonella on table eggs are low, which severely affects the sensitivity of sampling plans applied voluntarily in some European countries, where one to five pools of 10 eggs are tested by the culture based reference method ISO 6579:2004. In the current study we have compared the testing-sensitivity of the reference culture method ISO 6579:2004 and an alternative real-time PCR method on Salmonella contaminated egg-pool of different sizes (4-9 uninfected eggs mixed with one contaminated egg) and contamination levels (10°-10(1), 10(1)-10(2), 10(2)-10(3)CFU/eggshell). Two hundred and seventy samples corresponding to 15 replicates per pool size and inoculum level were tested. At the lowest contamination level real-time PCR detected Salmonella in 40% of contaminated pools vs 12% using ISO 6579. The results were used to estimate the lowest number of sample units needed to be tested in order to have a 95% certainty not falsely to accept a contaminated lot by Monte Carlo simulation. According to this simulation, at least 16 pools of 10 eggs each are needed to be tested by ISO 6579 in order to obtain this confidence level, while the minimum number of pools to be tested was reduced to 8 pools of 9 eggs each, when real-time PCR was applied as analytical method. This result underlines the importance of including analytical methods with higher sensitivity in order to improve the efficiency of sampling and reduce the number of samples to be tested. Copyright © 2013 Elsevier B.V. All rights reserved.

Ozone treatment of shell eggs to preserve functional quality and enhance shelf life during storage.

PubMed

Yüceer, Muhammed; Aday, Mehmet Seçkin; Caner, Cengiz

2016-06-01

Eggs have long been recognised as a source of high-quality proteins. Many methods exist to extend shelf life of food and one of them is ozone treatment, which is an emerging technology for disinfecting surfaces in the food industry. This study aimed to extend the shelf life of fresh eggs using gaseous ozone treatments at concentrations of 2, 4 and 6 ppm with exposure times of 2 and 5 min during storage for 6 weeks at 24 °C. The effect of the treatments on interior quality and functional properties of eggs is also reported. Ozone concentration and exposure time significantly affected the Haugh unit (HU), yolk index, albumen pH, relative whipping capacity (RWC), and albumen viscosity of eggs during the storage. Control eggs had the highest albumen pH and lowest albumen viscosity. Attributes such as albumen pH and RWC of eggs exposed to ozone treatments were better than the control samples. The measurement results showed that ozone concentration at 6 ppm and exposure time of 5 min can be applied to fresh eggs and extend shelf life up to 6 weeks at 24 °C storage period. Ozone treatments helped to maintain egg quality for a longer time. Ozone concentrations at 2 and 4 ppm showed promising results in maintaining internal quality and functional properties of fresh eggs during storage. Ozone at high concentration (6 ppm) caused a detrimental effect on eggshell quality. As a result, this study demonstrated that ozone treatments of 2, and especially 4 and 6 ppm concentration maintained eggshell quality during the storage. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Storage of Pentatomid Eggs in Liquid Nitrogen and Dormancy of Trissolcus basalis (Wollaston) and Telenomus podisi Ashmead (Hymenoptera: Platygastridae) Adults as a Method of Mass Production.

PubMed

Doetzer, A K; Foerster, L A

2013-10-01

The eggs of pentatomid species were evaluated to parasitism by Trissolcus basalis (Wollaston) and Telenomus podisi Ashmead after storage in liquid nitrogen. Adults which emerged from stored eggs were kept at 18°C for 120 and 180 days to investigate whether adult dormancy could be associated with host egg storage in liquid nitrogen as a method of mass production of these egg parasitoids. Eggs of Nezara viridula (L.) and Acrosternum pengue (Rolston) were successfully parasitized by T. basalis, as well as Piezodorus guildinii (Westwood) and Dichelops furcatus (F.) by T. podisi. The eggs of Edessa meditabunda (F.) were not parasitized by T. basalis. The emergence of T. podisi from eggs of Euschistus heros (F.) and Podisus nigrispinus (Dallas) stored for 6 months was lower than the control. Females of T. basalis and T. podisi that emerged from stored eggs were kept in dormancy at 18°C. Longevity of T. basalis was influenced by the storage time and sex, but not by the interaction of sex and storage time. For T. podisi, longevity was influenced by the storage time, sex, and by the interaction of sex and storage time. For T. basalis, storage in liquid nitrogen did not affect the fecundity of quiescent females, while the number of parasitized eggs by T. podisi decreased after storage. By the joint use of these techniques, it is possible to optimize mass production of T. basalis so that its life cycle can be monitored and synchronized with the life cycle and availability of hosts.

The Effect of Flunitrazepam (Rohypnol(®) ) on the Development of Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) and its Implications for Forensic Entomology.

PubMed

Baia, Tainá Costa; Campos, Alessandra; Wanderley, Bruno Mattos Silva; Gama, Renata Antonaci

2016-07-01

This study investigated the potential effects of flunitrazepam (known as "date rape drug") on the developmental cycle of Chrysomya megacephala, an important forensic species, and their possible implications for the calculation of the PMI. A 1050 C. megacephala eggs were divided into five groups with seven replications each. The eggs were placed on artificial diet prepared with four drug concentrations of flunitrazepam (4, 8, 16, and 32 ng/g), besides the control group (prepared with water). Were evaluated the potential effects on development time, weight gain, and mortality during the cycles. The drug had no significant effect on development time or mortality although it did affect the weight of the pupae and adults (Kruskal-Wallis, p < 0.05). The result can be deduced that the determination of the postmortem interval is not affected. © 2016 American Academy of Forensic Sciences.

A flotation/sieving method to detect Echinococcus multilocularis and Toxocara spp. eggs in soil by real-time PCR

PubMed Central

Umhang, Gérald; Bastien, Matthieu; Renault, Camille; Faisse, Marine; Caillot, Christophe; Boucher, Jean-Marc; Hormaz, Vanessa; Poulle, Marie-Lazarine; Boué, Franck

2017-01-01

Soil can be a source of human infection by many zoonotic helminth species including Echinococcus multilocularis and Toxocara spp. The prevention of alveolar echinococcosis could be greatly improved through the identification of at-risk areas. Yet very few data are available about the detection of E. multilocularis in soil, while more studies have been reported for Toxocara spp. Identification of soil contamination by E. multilocularis eggs requires the use of specific methods. This study describes the development of a method for the detection of E. multilocularis in soil samples with the concentration of eggs using a flotation/sieving method and detection by duplex real-time polymerase chain reaction (PCR). Toxocara spp. egg detection was also undertaken due to the widespread presence of this parasite in soil, despite it being considered less pathogenic. Method sensitivity of 100% was reached for the detection of 10 E. multilocularis eggs spiked in 10 g of soil. Concerning Toxocara spp., method sensitivity was lower but assumed to be due to the reduced effectiveness of the DNA extraction protocol. The parasitological status for E. multilocularis and Toxocara spp. of 63 carnivore fecal samples collected in highly endemic rural areas of France and of soil samples collected under and near these fecal samples was compared. The contamination of soil samples collected under positive fecal samples for E. multilocularis (n = 3) or Toxocara spp. (n = 19) confirmed the transfer of eggs from the definitive host to the environment. PMID:28737135

Development and reprotuction of Spodoptera eridania on natural hosts and artificial diet.

PubMed

Silva, A; Baronio, C A; Galzer, E C W; Garcia, M S; Botton, M

2018-04-09

The development and reproductive potential of Spodoptera eridania (Stoll, 1782) (Lepidoptera, Noctuidae) was compared on natural and artificial diets. Its biology was determined under laboratory conditions, providing an artificial diet, leaves of white clover and the peach cultivar 'Chimarrita' and fruits and leaves of the apple cultivar 'Gala'. Larvae of S. eridania could not complete their biological cycle when fed on apple fruits or peach leaves. The artificial diet provided the shortest development time, with a cycle of 28.5±0.14 days from egg to adult and 37.3% total viability. Apple leaves led to a longer development time from egg to adult (62.8±1.22 days) and lower total viability (23%) and white clover provided the highest total viability (54.3%). The results showed that S. eridania can use white clover and apple leaves to develop normally in apple orchards. The reduction of food sources such as white clover used by the larvae results in infestation and damage to fruits from "test bites".

Compatibility of the entomopathogenic fungus Beauveria bassiana with flufenoxuron and azadirachtin against Tetranychus urticae.

PubMed

Hernández, M M; Martínez-Villar, E; Peace, C; Pérez-Moreno, I; Marco, V

2012-12-01

Laboratory studies were developed to evaluate the compatibility of flufenoxuron and azadirachtin with Beauveria bassiana against Tetranychus urticae larvae along with the required Probit analysis of the involved chemicals on all of the life stages of this mite. Flufenoxuron displayed parallel regression lines for the mortality of eggs, deutonymphs and adults. Larvae and protonymphs were the most susceptible life stages. Protonymphs were 35 times more sensitive than eggs and adults. Azadirachtin gave equal mortality on proto- and deutonymphs. The response of eggs and adults was equivalent when treated with azadirachtin. The regression lines for proto- and deutonymphs were parallel to those of adults and eggs yet three times more sensitive. The effects of separate combinations of the entomopathogenic fungus Beauveria bassiana at its LC(20) with flufenoxuron and azadirachtin at their corresponding LC(40) were evaluated on mite larvae. The application of flufenoxuron with B. bassiana revealed a clear synergy. While the combination of azadirachtin and B. bassiana had an additive effect. These combinations with B. bassiana could improve mite control by contributing to a decline in the likelihood of resistance so often described in the literature.

Life history of two abundant populations of Dipetalogaster maximus (Uhler, 1894) (Hemiptera: Reduviidae: Triatominae) in northwestern Mexico.

PubMed

Martínez-Ibarra, José Alejandro; Nogueda-Torres, Benjamín; Cárdenas-Barón, Anahí Citlalli; Montañez-Valdez, Oziel Dante; Bustos-Saldaña, Rafael; Meillón-Isáis, Karla Mirella

2018-06-01

We focused on the analysis of biological parameters of two different abundant populations of Dipetalogaster maximus (Uhler) (Hemiptera: Reduviidae: Triatominae) from northwestern Mexico. The biological parameters were related to hatching of eggs, life cycle, and meal needed for molting by each instar of two populations from environmentally similar areas (El Fandango and San Dionisio) with a similar number of available hosts as blood meal sources. The D. maximus populations from the two locations were evaluated and compared. No significant differences (P>0.05) were recorded for the average hatching time of the two cohorts. The median egg-to-adult development time and the number of blood meals at each nymphal group were significantly shorter (P<0.05) for the El Fandango cohort. The number of obtained females at the end of the cycles, number of eggs laid, and rate of egg hatching were significantly higher (P<0.05) for the El Fandango cohort. These results contribute to the estimation of abundances of the studied populations of D. maximus in areas where many tourists go for camping and have an increased risk of being bitten and infected by this species. © 2018 The Society for Vector Ecology.

Timing of sperm penetration, pronuclear formation, pronuclear DNA synthesis, and first cleavage in naturally ovulated mouse eggs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishna, M.; Generoso, W.M.

1977-11-01

Timing of development of naturally ovulated mouse eggs from sperm penetration to first cleavage, including that of DNA synthesis, was established. In an attempt to limit variability, partial synchronization of ovulation was accomplished by shortening the length of the dark period to five hours, and partial synchronization of sperm entry was attempted by mating the females soon after the ovulated eggs reached the ampulla and by limiting the period at which mating could occur to only 20 minutes. Evidence of sperm penetration (presence of one or more sperm in perivitelline space or inside the vitellus) was found beginning 1.75 hoursmore » after the end of the mating period. Pronuclei were formed three to four hours after sperm entry. Pronuclear DNA synthesis began about eight hours postmating, 3.25 to 4.5 hours after pronuclear formation, or about 6.25 to 8.5 hours after sperm entry; it was completed in almost all zygotes by 16 hours postmating. The first completed cleavage division was found 17 to 18 hours postmating, and almost all eggs had cleaved by 20 hours.« less

Calcium signaling in mammalian egg activation and embryo development: Influence of subcellular localization

PubMed Central

Miao, Yi-Liang; Williams, Carmen J.

2012-01-01

Calcium (Ca2+) signals drive the fundamental events surrounding fertilization and the activation of development in all species examined to date. Initial studies of Ca2+ signaling at fertilization in marine animals were tightly linked to new discoveries of bioluminescent proteins and their use as fluorescent Ca2+ sensors. Since that time, there has been rapid progress in our understanding of the key functions for Ca2+ in many cell types and the impact of cellular localization on Ca2+ signaling pathways. In this review, which focuses on mammalian egg activation, we consider how Ca2+ is regulated and stored at different stages of oocyte development and examine the functions of molecules that serve as both regulators of Ca2+ release and effectors of Ca2+ signals. We then summarize studies exploring how Ca2+ directs downstream effectors mediating both egg activation and later signaling events required for successful preimplantation embryo development. Throughout this review, we focus attention on how localization of Ca2+ signals influences downstream signaling events, and attempt to highlight gaps in our knowledge that are ripe areas for future research. PMID:22888043

Oviposition, Life Cycle, and Longevity of the Leaf-Cutting Ant Acromyrmex rugosus rugosus.

PubMed

Verza, Sandra S; Mussury, Rosilda M; Camargo, Roberto S; Andrade, Ana Paula P; Forti, Luiz C

2017-08-04

Studies related to the demography of individual members from ant colonies have received little attention, although they are the basis to understanding the population dynamics of colonies. Thus, the objective of this work was to study the queen oviposition rate and the duration of the life cycle and longevity of Acromyrmex rugosus rugosus workers. To determine the oviposition rate, queens from three colonies were individually placed in plastic containers, and the eggs laid were quantified over a 96 h period. The development of the immature forms was observed every 24 h, with which the duration of each stage of development was determined. To verify the longevity of workers, the newly emerged adults were marked and daily observations were made. According to the results, there is variation in the development time of immature forms within the colony itself and between colonies. In addition, the number of eggs deposited was also inconstant in the three colonies, ranging from 5 to 119 eggs per day, while the longevity of workers varied from 3 to 7 months. Occasionally, it was found that the workers feed on the eggs produced by the queen; besides, there was a disappearance of larvae and pupae during the research, indicating a possibility of the practice of cannibalism in this species.

Development of chicken embryos in a pulsed magnetic field.

PubMed

Berman, E; Chacon, L; House, D; Koch, B A; Koch, W E; Leal, J; Løvtrup, S; Mantiply, E; Martin, A H; Martucci, G I

1990-01-01

Six independent experiments of common design were performed in laboratories in Canada, Spain, Sweden, and the United States of America. Fertilized eggs of domestic chickens were incubated as controls or in a pulsed magnetic field (PMF); embryos were then examined for developmental anomalies. Identical equipment in each laboratory consisted of two incubators, each containing a Helmholtz coil and electronic devices to develop, control, and monitor the pulsed field and to monitor temperature, relative humidity, and vibrations. A unipolar, pulsed, magnetic field (500-microseconds pulse duration, 100 pulses per s, 1-microT peak density, and 2-microseconds rise and fall time) was applied to experimental eggs during 48 h of incubation. In each laboratory, ten eggs were simultaneously sham exposed in a control incubator (pulse generator not activated) while the PMF was applied to ten eggs in the other incubator. The procedure was repeated ten times in each laboratory, and incubators were alternately used as a control device or as an active source of the PMF. After a 48-h exposure, the eggs were evaluated for fertility. All embryos were then assayed in the blind for development, morphology, and stage of maturity. In five of six laboratories, more exposed embryos exhibited structural anomalies than did controls, although putatively significant differences were observed in only two laboratories (two-tailed Ps of .03 and less than .001), and the significance of the difference in a third laboratory was only marginal (two-tailed P = .08). When the data from all six laboratories are pooled, the difference in incidence of abnormalities in PMF-exposed embryos (approximately 25 percent) and that of controls (approximately 19 percent), although small, is highly significant, as is the interaction between incidence of abnormalities and laboratory site (both Ps less than .001). The factor or factors responsible for the marked variability of inter-laboratory differences are unknown.

Cholecystolithiasis is associated with Clonorchis sinensis infection.

PubMed

Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Luo, Zhen-liang; Zheng, Pei-ming

2012-01-01

The objective of this study was to analyze gallbladder stones for direct evidence of a relationship between Clonorchis sinensis infection and gallbladder stones formation. We investigated one hundred eighty-three gallbladder stones for the presence of Clonorchis sinensis eggs using microscopy, and analyzed their composition using Fourier transform infrared spectroscopy. We confirmed the presence of Clonorchis sinensis eggs in the gallbladder stones using real-time fluorescent PCR and scanning electron microscopy. Clonorchis sinensis eggs were detected in 122 of 183 gallbladder stones based on morphologic characteristics and results from real-time fluorescent PCR. The proportion of pigment stones, cholesterol stones and mixed gallstones in the egg-positive stones was 79.5% (97/122), 3.3% (4/122) and 17.2% (21/122), respectively, while 29.5% (18/61), 31.1% (19/61) and 39.3% (24/61) in the egg-negative stones. The proportion of pigment stone in the Clonorchis sinensis egg-positive stones was higher than in egg-negative stones (P<0.0001). In the 30 egg-positive stones examined by scanning electron microscopy, dozens or even hundreds of Clonorchis sinensis eggs were visible (×400) showing a distinct morphology. Many eggs were wrapped with surrounding particles, and in some, muskmelon wrinkles was seen on the surface of the eggs. Also visible were pieces of texture shed from some of the eggs. Some eggs were depressed or without operculum while most eggs were adhered to or wrapped with amorphous particles or mucoid matter (×3000). Clonorchis sinensis eggs were detected in the gallbladder stones which suggests an association between Clonorchis sinensis infection and gallbladder stones formation, especially pigment stones.

Heat Resistance of Salmonella in Various Egg Products

PubMed Central

Garibaldi, J. A.; Straka, R. P.; Ijichi, K.

1969-01-01

The heat-resistance characteristics of Salmonella typhimurium Tm-1, a reference strain in the stationary phase of growth, were determined at several temperatures in the major types of products produced by the egg industry. The time required to kill 90% of the population (D value) at a given temperature in specific egg products was as follows: at 60 C (140 F), D = 0.27 min for whole egg; D = 0.60 min for whole egg plus 10% sucrose; D = 1.0 min for fortified whole egg; D = 0.20 min for egg white (pH 7.3), stabilized with aluminum; D = 0.40 min for egg yolk; D = 4.0 min for egg yolk plus 10% sucrose; D = 5.1 min for egg yolk plus 10% NaCl; D = 1.0 min for scrambled egg mix; at 55 C (131 F), D = 0.55 min for egg white (pH 9.2); D = 1.2 min for egg white (pH 9.2) plus 10% sucrose. The average Z value (number of degrees, either centigrade or fahrenheit, for a thermal destruction time curve to traverse one logarithmic cycle) was 4.6 C (8.3 F) with a range from 4.2 to 5.3 C. Supplementation with 10% sucrose appeared to have a severalfold greater effect on the heat stabilization of egg white proteins than on S. typhimurium Tm-1. This information should be of value in the formulation of heat treatments to insure that all egg products be free of viable salmonellae. Images PMID:4890741

Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination

USGS Publications Warehouse

Taylor, Gregory T.; Ackerman, Joshua T.; Shaffer, Scott A.

2018-01-01

Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster’s terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior.

Egg turning behavior and incubation temperature in Forster's terns in relation to mercury contamination.

PubMed

Taylor, Gregory T; Ackerman, Joshua T; Shaffer, Scott A

2018-01-01

Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster's terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior.

Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination

PubMed Central

Ackerman, Joshua T.; Shaffer, Scott A.

2018-01-01

Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster’s terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior. PMID:29447185

Effects of Salivary Gland Hypertrophy Virus on the Reproductive Behavior of the Housefly, Musca domestica▿

PubMed Central

Lietze, Verena-Ulrike; Geden, Christopher J.; Blackburn, Patrick; Boucias, Drion G.

2007-01-01

Pathological studies demonstrated that the salivary gland hypertrophy virus of houseflies (MdSGHV) shuts down reproduction in infected females. The mechanism that underlay the disruption of reproduction functioned on several levels. Females infected at the previtellogenic stage did not produce eggs, reflecting a block in the gonadotropic cycle. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis of hemolymph samples demonstrated that MdSGHV infection reduced the levels of both the female-specific hexamerin and egg yolk proteins. Furthermore, reverse transcriptase quantitative real-time PCR data demonstrated that infection blocked hexamerin and yolk protein gene transcription. When females were allowed to develop eggs prior to infection (postvitellogenic stage), the outcome of mating attempts depended upon when mating took place. If egg-containing, virus-infected females were mated within 24 h of infection, they copulated and deposited a single batch of fertilized eggs. However, if mating was delayed for a longer period, the egg-containing females refused to copulate with healthy males. Both of these results suggested that a virus-induced signal influenced the central nervous system, shutting down female receptivity and egg production. All experiments demonstrated that MdSGHV-infected males did not display azoospermia and were fertile. Both healthy females mated with infected males, and the resulting F1 progeny were free of salivary gland hypertrophy symptoms, which suggests that the virus is not sexually or vertically transmitted. PMID:17827327

Loop-mediated isothermal amplification assay for detection and discrimination of Toxocara canis and Toxocara cati eggs directly from sand samples.

PubMed

Macuhova, K; Kumagai, T; Akao, N; Ohta, N

2010-12-01

We developed a novel and simple method, using loop-mediated isothermal amplification (LAMP), for the detection and discrimination of Toxocara canis and Toxocara cati eggs. The new method employs 4 steps: (1) concentration of Toxocara eggs in a small amount of sand; (2) dissolution of the proteinaceous membrane of eggs and simultaneously separation of them from the sand using NaClO treatment; (3) extraction of DNA using NaOH treatment; and (4) detection of T. canis / T. cati DNA using a LAMP assay. All these steps are fast, easy to perform, and do not require expensive equipment or reagents. The novel method was tested both experimentally and in a field study. In the laboratory, we could reliably detect as few as 3 T. canis eggs in artificially contaminated sand, if the experiment was repeated twice. In the field trial, we were able to detect T. cati DNA from 4 natural sandpits having moderate to heavy contamination, although not in a single lightly contaminated sandpit. All of the examined sandpits were found to be contaminated with eggs of T. cati, but none appeared to contain T. canis. Our new method could extract DNA from T. canis and T. cati eggs directly from sand samples as well as detect and distinguish these 2 species in a few easy steps, with markedly reduced time and expense.

Migratory life histories explain the extreme egg-size dimorphism of Eudyptes penguins

PubMed Central

Williams, Tony D.

2016-01-01

When successive stages in the life history of an animal directly overlap, physiological conflicts can arise resulting in carryover effects from one stage to another. The extreme egg-size dimorphism (ESD) of Eudyptes penguins, where the first-laid A-egg is approximately 18–57% smaller than the second-laid B-egg, has interested researchers for decades. Recent studies have linked variation in this trait to a carryover effect of migration that limits the physiology of yolk production and egg sizes. We assembled data on ESD and estimates of migration–reproduction overlap in penguin species and use phylogenetic methods to test the idea that migration–reproduction overlap explains variation in ESD. We show that migration overlap is generally restricted to Eudyptes relative to non-Eudyptes penguins, and that this overlap (defined as the amount of time that egg production occurs on land versus at sea during homeward migration) is significantly and positively correlated with the degree of ESD in Eudyptes. In the non-Eudyptes species, however, ESD was unrelated to migration overlap as these species mostly produce their clutches on land. Our results support the recent hypothesis that extreme ESD of Eudyptes penguins evolved, in part, as a response to selection for a pelagic overwinter migration behaviour. This resulted in a temporal overlap with, and thus a constraint on, the physiology of follicle development, leading to smaller A-egg size and greater ESD. PMID:27708146

A method for collecting eggs of Pseudocapillaria tomentosa (Nematoda: Capillariidae) from zebrafish Danio rerio and efficacy of heat and chlorine for killing the nematode’s eggs

PubMed Central

Martins, ML; Watral, V; Rodrigues-Soares, JP; Kent, ML

2016-01-01

Pseudocapillaria tomentosa is a common pathogen of zebrafish (Danio rerio) in research facilities. We developed a method to collect and concentrate the nematode eggs using a modified sugar centrifugation method, and documented their normal development. Embryonating stages with blastomere formation followed by elongation of the embryo prior to larva formation cumulated in developed larvae inside the eggs and hatching after 5–10 d. We then evaluated the efficacy of heat and chlorine to kill them based on a larva development assay. Eggs were exposed to 40, 50, 60°C for 30 min and 1 h. Chlorine treatment was performed at 100, 250, 500, 1000, 3000 and 6000 ppm for 10 min. Samples exposed to 40°C for 30 min or 1 h showed incidences of larvated eggs similar to controls. In contrast, no larvation occurred with eggs exposed to either 50 or 60°C for 30 min or 1 h. Remarkably, in repeated assays, samples exposed to low doses of chlorine (100, 250, 500 and 1000 ppm for 10 min) showed significantly higher incidence of larvation than controls. Eggs treated with 3,000 ppm for 10 min did not develop larvae and no eggs were found after 6,000 ppm treatment. PMID:27334246

Rapid Surveillance for Vector Presence (RSVP): Development of a novel system for detecting Aedes aegypti and Aedes albopictus.

PubMed

Montgomery, Brian L; Shivas, Martin A; Hall-Mendelin, Sonja; Edwards, Jim; Hamilton, Nicholas A; Jansen, Cassie C; McMahon, Jamie L; Warrilow, David; van den Hurk, Andrew F

2017-03-01

The globally important Zika, dengue and chikungunya viruses are primarily transmitted by the invasive mosquitoes, Aedes aegypti and Aedes albopictus. In Australia, there is an increasing risk that these species may invade highly urbanized regions and trigger outbreaks. We describe the development of a Rapid Surveillance for Vector Presence (RSVP) system to expedite presence- absence surveys for both species. We developed a methodology that uses molecular assays to efficiently screen pooled ovitrap (egg trap) samples for traces of target species ribosomal RNA. Firstly, specific real-time reverse transcription-polymerase chain reaction (RT-PCR) assays were developed which detect a single Ae. aegypti or Ae. albopictus first instar larva in samples containing 4,999 and 999 non-target mosquitoes, respectively. ImageJ software was evaluated as an automated egg counting tool using ovitrap collections obtained from Brisbane, Australia. Qualitative assessment of ovistrips was required prior to automation because ImageJ did not differentiate between Aedes eggs and other objects or contaminants on 44.5% of ovistrips assessed, thus compromising the accuracy of egg counts. As a proof of concept, the RSVP was evaluated in Brisbane, Rockhampton and Goomeri, locations where Ae. aegypti is considered absent, present, and at the margin of its range, respectively. In Brisbane, Ae. aegypti was not detected in 25 pools formed from 477 ovitraps, comprising ≈ 54,300 eggs. In Rockhampton, Ae. aegypti was detected in 4/6 pools derived from 45 ovitraps, comprising ≈ 1,700 eggs. In Goomeri, Ae. aegypti was detected in 5/8 pools derived from 62 ovitraps, comprising ≈ 4,200 eggs. RSVP can rapidly detect nucleic acids from low numbers of target species within large samples of endemic species aggregated from multiple ovitraps. This screening capability facilitates deployment of ovitrap configurations of varying spatial scales, from a single residential block to entire suburbs or towns. RSVP is a powerful tool for surveillance of invasive Aedes spp., validation of species eradication and quality assurance for vector control operations implemented during disease outbreaks.

Rapid Surveillance for Vector Presence (RSVP): Development of a novel system for detecting Aedes aegypti and Aedes albopictus

PubMed Central

Montgomery, Brian L.; Shivas, Martin A.; Hall-Mendelin, Sonja; Edwards, Jim; Hamilton, Nicholas A.; Jansen, Cassie C.; McMahon, Jamie L.; Warrilow, David

2017-01-01

Background The globally important Zika, dengue and chikungunya viruses are primarily transmitted by the invasive mosquitoes, Aedes aegypti and Aedes albopictus. In Australia, there is an increasing risk that these species may invade highly urbanized regions and trigger outbreaks. We describe the development of a Rapid Surveillance for Vector Presence (RSVP) system to expedite presence- absence surveys for both species. Methodology/Principal findings We developed a methodology that uses molecular assays to efficiently screen pooled ovitrap (egg trap) samples for traces of target species ribosomal RNA. Firstly, specific real-time reverse transcription-polymerase chain reaction (RT-PCR) assays were developed which detect a single Ae. aegypti or Ae. albopictus first instar larva in samples containing 4,999 and 999 non-target mosquitoes, respectively. ImageJ software was evaluated as an automated egg counting tool using ovitrap collections obtained from Brisbane, Australia. Qualitative assessment of ovistrips was required prior to automation because ImageJ did not differentiate between Aedes eggs and other objects or contaminants on 44.5% of ovistrips assessed, thus compromising the accuracy of egg counts. As a proof of concept, the RSVP was evaluated in Brisbane, Rockhampton and Goomeri, locations where Ae. aegypti is considered absent, present, and at the margin of its range, respectively. In Brisbane, Ae. aegypti was not detected in 25 pools formed from 477 ovitraps, comprising ≈ 54,300 eggs. In Rockhampton, Ae. aegypti was detected in 4/6 pools derived from 45 ovitraps, comprising ≈ 1,700 eggs. In Goomeri, Ae. aegypti was detected in 5/8 pools derived from 62 ovitraps, comprising ≈ 4,200 eggs. Conclusions/Significance RSVP can rapidly detect nucleic acids from low numbers of target species within large samples of endemic species aggregated from multiple ovitraps. This screening capability facilitates deployment of ovitrap configurations of varying spatial scales, from a single residential block to entire suburbs or towns. RSVP is a powerful tool for surveillance of invasive Aedes spp., validation of species eradication and quality assurance for vector control operations implemented during disease outbreaks. PMID:28339458

The Genetic Basis of Natural Variation in Drosophila (Diptera: Drosophilidae) Virgin Egg Retention.

PubMed

Akhund-Zade, Jamilla; Bergland, Alan O; Crowe, Sarah O; Unckless, Robert L

2017-01-01

Drosophila melanogaster is able to thrive in harsh northern climates through adaptations in life-history traits and physiological mechanisms that allow for survival through the winter. We examined the genetic basis of natural variation in one such trait, female virgin egg retention, which was previously shown to vary clinally and seasonally. To further our understanding of the genetic basis and evolution of virgin egg retention, we performed a genome-wide association study (GWAS) using the previously sequenced Drosophila Genetic Reference Panel (DGRP) mapping population. We found 29 single nucleotide polymorphisms (SNPs) associated with virgin egg retention and assayed 6 available mutant lines, each harboring a mutation in a candidate gene, for effects on egg retention time. We found that four out of the six mutant lines had defects in egg retention time as compared with the respective controls: mun, T48, Mes-4, and Klp67A Surprisingly, none of these genes has a recognized role in ovulation control, but three of the four genes have known effects on fertility or have high expression in the ovaries. We also found that the SNP set associated with egg retention time was enriched for clinal SNPs. The majority of clinal SNPs had alleles associated with longer egg retention present at higher frequencies in higher latitudes. Our results support previous studies that show higher frequency of long retention times at higher latitude, providing evidence for the adaptive value of virgin egg-retention. © The Author 2017. Published by Oxford University Press on behalf of the Entomological Society of America.

Temperature effects on egg development and larval condition in the lesser sandeel, Ammodytes marinus

NASA Astrophysics Data System (ADS)

Régnier, Thomas; Gibb, Fiona M.; Wright, Peter J.

2018-04-01

Understanding the influence of temperature on egg development and larval condition in planktonic fish is a prerequisite to understanding the phenological impacts of climate change on marine food-webs. The lesser sandeel, Ammodytes marinus (Raitt 1934), is a key trophic link between zooplankton and many piscivorous fish, sea birds and mammals in the northeast Atlantic. Temperature-egg development relationships were determined for batches of lesser sandeel eggs. Hatching began as early as 19 days post fertilisation at 11 °C and as late as 36 days post fertilisation at 6 °C, which is faster than egg development rates reported for closely related species at the lower end of the tested temperature range. The average size of newly hatched larvae decreased with increasing incubation temperatures in early hatching larvae, but this effect was lost by the middle of the hatching period. While the study revealed important temperature effects on egg development rate, predicted variability based on the range of temperatures eggs experience in the field, suggests it is only a minor contributor to the observed inter-annual variation in hatch date.

Developing logistic regression models using purchase attributes and demographics to predict the probability of purchases of regular and specialty eggs.

PubMed

Bejaei, M; Wiseman, K; Cheng, K M

2015-01-01

Consumers' interest in specialty eggs appears to be growing in Europe and North America. The objective of this research was to develop logistic regression models that utilise purchaser attributes and demographics to predict the probability of a consumer purchasing a specific type of table egg including regular (white and brown), non-caged (free-run, free-range and organic) or nutrient-enhanced eggs. These purchase prediction models, together with the purchasers' attributes, can be used to assess market opportunities of different egg types specifically in British Columbia (BC). An online survey was used to gather data for the models. A total of 702 completed questionnaires were submitted by BC residents. Selected independent variables included in the logistic regression to develop models for different egg types to predict the probability of a consumer purchasing a specific type of table egg. The variables used in the model accounted for 54% and 49% of variances in the purchase of regular and non-caged eggs, respectively. Research results indicate that consumers of different egg types exhibit a set of unique and statistically significant characteristics and/or demographics. For example, consumers of regular eggs were less educated, older, price sensitive, major chain store buyers, and store flyer users, and had lower awareness about different types of eggs and less concern regarding animal welfare issues. However, most of the non-caged egg consumers were less concerned about price, had higher awareness about different types of table eggs, purchased their eggs from local/organic grocery stores, farm gates or farmers markets, and they were more concerned about care and feeding of hens compared to consumers of other eggs types.

Environmental contamination with Toxocara eggs: a quantitative approach to estimate the relative contributions of dogs, cats and foxes, and to assess the efficacy of advised interventions in dogs.

PubMed

Nijsse, Rolf; Mughini-Gras, Lapo; Wagenaar, Jaap A; Franssen, Frits; Ploeger, Harm W

2015-07-28

Environmental contamination with Toxocara eggs is considered the main source of human toxocariasis. The contribution of different groups of hosts to this contamination is largely unknown. Current deworming advices focus mainly on dogs. However, controversy exists about blind deworming regimens for >6-month-old dogs, as most of them do not actually shed Toxocara eggs. We aim to estimate the contribution of different non-juvenile hosts to the environmental Toxocara egg contamination and to assess the effects of different Toxocara-reducing interventions for dogs. A stochastic model was developed to quantify the relative contribution to the environmental contamination with Toxocara eggs of household dogs, household cats, stray cats, and foxes, all older than 6 months in areas with varying urbanization degrees. The model was built upon an existing model developed by Morgan et al. (2013). We used both original and published data on host density, prevalence and intensity of infection, coprophagic behaviour, faeces disposal by owners, and cats' outdoor access. Scenario analyses were performed to assess the expected reduction in dogs' egg output according to different deworming regimens and faeces clean-up compliances. Estimates referred to the Netherlands, a country free of stray dogs. Household dogs accounted for 39% of the overall egg output of >6-month-old hosts in the Netherlands, followed by stray cats (27%), household cats (19%), and foxes (15%). In urban areas, egg output was dominated by stray cats (81%). Intervention scenarios revealed that only with a high compliance (90%) to the four times a year deworming advice, dogs' contribution would drop from 39 to 28%. Alternatively, when 50% of owners would always remove their dogs' faeces, dogs' contribution would drop to 20%. Among final hosts of Toxocara older than 6 months, dogs are the main contributors to the environmental egg contamination, though cats in total (i.e. both owned and stray) transcend this contribution. A higher than expected compliance to deworming advice is necessary to reduce dogs' egg output meaningfully. Actions focusing solely on household dogs and cats are unlikely to sufficiently reduce environmental contamination with eggs, as stray cats and foxes are also important contributors.

Production of adenovirus vectors and their use as a delivery system for influenza vaccines

PubMed Central

Vemula, Sai V.; Mittal, Suresh K.

2010-01-01

IMPORTANCE OF THE FIELD With the emergence of highly pathogenic avian influenza H5N1 viruses that have crossed species barriers and are responsible for lethal infections in humans in many countries, there is an urgent need for the development of effective vaccines which can be produced in large quantities at a short notice and confer broad protection against these H5N1 variants. In order to meet the potential global vaccine demand in a pandemic scenario, new vaccine-production strategies must be explored in addition to the currently used egg-based technology for seasonal influenza. AREAS COVERED IN THIS REVIEW Adenovirus (Ad) based influenza vaccines represent an attractive alternative/supplement to the currently licensed egg-based influenza vaccines. Ad-based vaccines are relatively inexpensive to manufacture, and their production process does not require either chicken eggs or labor intensive and time-consuming processes necessitating enhanced biosafety facilities. Most importantly, in a pandemic situation, this vaccine strategy could offer a stockpiling option to reduce the response time before a strain-matched vaccine could be developed. WHAT THE READER WILL GAIN This review discusses Ad-vector technology and the current progress in the development of Ad-based influenza vaccines. TAKE HOME MESSAGE Ad vector-based influenza vaccines for pandemic preparedness are under development to meet the global vaccine demand. PMID:20822477

The effects of levetiracetam on neural tube development in the early stage of chick embryos.

PubMed

Guvenc, Yahya; Dalgic, Ali; Billur, Deniz; Karaoglu, Derya; Aydin, Sevim; Daglioglu, Ergun; Ozdol, Cagatay; Nacar, Osman Arikan; Yildirim, Ali Erdem; Belen, Deniz

2013-01-01

This study aimed to investigate the effects of a new generation antiepileptic agent, levetiracetam, on the neural tube development in a chick embryo model that corresponds to the first month of vertebral development in mammals. Forty-five Atabey® breed fertilized chicken eggs with no specific pathogens were randomly divided into 5 groups. All of the eggs were incubated at 37.8±2°C and 60±5 % relative humidity in an incubator. Group A was control group. The other eggs were applied physiological saline and drugs at a volume of 10 μL by the in ovo method at the 28th hour of the incubation period. Group B was given distilled water; Group C, physiological saline; Group D, Levetiracetam (L8668) at a dose equivalent to the treatment dose for humans (10 mg/ kg), and Group E, Levetiracetam (L8668) at a dose of 10 times the treatment dose. The embryos in all of the groups were removed from the shells at the 48th hour and morphologically and histologically evaluated. Of the 45 embryos incubated, neural tubes of 41 were closed and the embryos displayed normal development. Levetiracetam, at a dose equivalent to human treatment dose and 10 times the treatment dose, was shown not to cause neural tube defects in chick embryos.

Water-vapor conductance of testudinian and crocodilian eggs (class reptilia).

PubMed

Packard, G C; Taigen, T L; Packard, M J; Shuman, R D

1979-09-01

Flexible-shelled eggs of snapping turtles (Chelydra serpentina) have conductances to water vapor that are 55 times higher than predicted for avian eggs of similar size, whereas rigid-shelled eggs of softshell turtles (Trionyx spiniferus) and American alligators (Alligator mississippiensis) have conductances that are only five times higher than expected for comparable eggs of birds. The differences between empirical and predicted values result from the much higher effective pore areas in reptilian eggshells than in those of birds. The relatively high porosities of these reptilian eggs presumably facilitate the transport of oxygen and carbon dioxide eggshells in later stages of incubation when air trapped inside nest chambers may become hypoxic and hypercapnic, yet seem not to lead to excessive transpiration of water vapor owing to the high humidities in nests where incubation occurs.

Development of a Fluvial Egg Drift Simulator to evaluate the transport and dispersion of Asian carp eggs in rivers

USGS Publications Warehouse

Garcia, Tatiana; Jackson, P. Ryan; Murphy, Elizabeth A.; Valocchi, Albert J.; Garcia, Marcelo H.

2013-01-01

Asian carp are migrating towards the Great Lakes and are threatening to invade this ecosystem, hence there is an immediate need to control their population. The transport of Asian carp eggs in potential spawning rivers is an important factor in its life history and recruitment success. An understanding of the transport, development, and fate of Asian carp eggs has the potential to create prevention, management, and control strategies before the eggs hatch and develop the ability to swim. However, there is not a clear understanding of the hydrodynamic conditions at which the eggs are transported and kept in suspension. This knowledge is imperative because of the current assumption that suspension is required for the eggs to survive. Herein, FluEgg (Fluvial Egg Drift Simulator), a three-dimensional Lagrangian model capable of evaluating the influence of flow velocity, shear dispersion and turbulent diffusion on the transport and dispersal patterns of Asian carp eggs is presented. The model's variables include not only biological behavior (growth rate, density changes) but also the physical characteristics of the flow field, such as mean velocities and eddy diffusivities. The performance of the FluEgg model was evaluated using observed data from published flume experiments conducted in China with water-hardened Asian carp eggs as subjects. FluEgg simulations show a good agreement with the experimental data. The model was also run with observed data from the Sandusky River in Ohio to provide a real-world demonstration case. This research will support the identification of critical hydrodynamic conditions (e.g., flow velocity, depth, and shear velocity) to maintain eggs in suspension, assist in the evaluation of suitable spawning rivers for Asian carp populations and facilitate the development of prevention, control and management strategies for Asian carp species in rivers and water bodies.

Multicomponent T2 relaxation studies of the avian egg.

PubMed

Mitsouras, Dimitris; Mulkern, Robert V; Maier, Stephan E

2016-05-01

To investigate the tissue-like multiexponential T2 signal decays in avian eggs. Transverse relaxation studies of raw, soft-boiled and hard-boiled eggs were performed at 3 Tesla using a three-dimensional Carr-Purcell-Meiboom-Gill imaging sequence. Signal decays over a TE range of 11 to 354 ms were fitted assuming single- and multicomponent signal decays with up to three separately decaying components. Fat saturation was used to facilitate spectral assignment of observed decay components. Egg white, yolk and the centrally located latebra all demonstrate nonmonoexponential T2 decays. Specifically, egg white exhibits two-component decays with intermediate and long T2 times. Meanwhile, yolk and latebra are generally best characterized with triexponential decays, with short, intermediate and very long T2 decay times. Fat saturation revealed that the intermediate component of yolk could be attributed to lipids. Cooking of the egg profoundly altered the decay curves. Avian egg T2 decay curves cover a wide range of decay times. Observed T2 components in yolk and latebra as short as 10 ms, may prove valuable for testing clinical sequences designed to measure short T2 components, such as myelin-associated water in the brain. Thus we propose that the egg can be a versatile and widely available MR transverse relaxation phantom. © 2015 Wiley Periodicals, Inc.

The decline of an adaptation in the absence of a presumed selection pressure

USGS Publications Warehouse

Cruz, A.; Wiley, J.W.

1989-01-01

The colonial nesting Village Weaver (Ploceus cucullatus) lays eggs that vary in ground color and pattern, but individual females lay similar eggs each time. Tests on captive African stocks have shown that females reject eggs of other cohorts if such eggs are sufficiently different.

Effect of microwave exposure on the ovarian development of Drosophila melanogaster.

PubMed

Panagopoulos, Dimitris J

2012-06-01

In the present experiments the effect of GSM radiation on ovarian development of virgin Drosophila melanogaster female insects was studied. Newly emerged adult female flies were collected and divided into separate identical groups. After the a lapse of certain number of hours-different for each group-the insects (exposed and sham-exposed) were dissected and their intact ovaries were collected and photographed under an optical microscope with the same magnification. The size of the ovaries was compared between exposed and sham-exposed virgin female insects, during the time needed for the completion of oogenesis and maturation of the first eggs in the ovarioles. Immediately after the intact ovaries were photographed, they were further dissected into individual ovarioles and treated for TUNEL and acridine-orange assays to determine the degree of DNA damage in the egg chamber cells. The study showed that the ovarian size of the exposed insects is significantly smaller than that of the corresponding sham-exposed insects, due to destruction of egg chambers by the GSM radiation, after DNA damage and consequent cell death induction in the egg chamber cells of the virgin females as shown in previous experiments on inseminated females. The difference in ovarian size between sham-exposed and exposed virgin female flies becomes most evident 39-45 h after eclosion when the first eggs within the ovaries are at the late vitellogenic and post-vitellogenic stages (mid-late oogenesis). More than 45 h after eclosion, the difference in ovarian size decreases, as the first mature eggs of the sham-exposed insects are leaving the ovaries and are laid.

[Chronologic, structural and biometric study of the egg and its development of the small spotted dogfish (Scyliorhinus canicula) raised in artificial seawater].

PubMed

Foulley, M M; Mellinger, J

1980-01-01

The eggs of the small spotted dogfish (Scyliorhinus canicula), developed in artificial sea water at 14 degrees C, pre-hatched after 3 to 3 1/2 months (total embryo length: 31 to 38 mm). Hatching occurred after 6 1/2 to 7 1/2 months (length of newborn: 80 to 95 mm). Egg weight first increased for 12 days and then remained constant until pre-hatching. A biometric study of the whole egg, egg case and albumen chamber showed very little variation in egg width, while egg length varied widely. As laying occurs in pairs, the secretory activity in each nidamental gland was observed to adapt to the extra volume of egg case contents in two cases where a double egg was laid with a normal one. However, the size and shape of the normal eggs of each female were generally distinctive, regardless of the contents or the external conditions. The egg case wall had three separate layers, as shown by microscopy of fresh material and experimental studies with various dyes.

Oxygen Consumption is Limited at an Ecologically Relevant Rearing Temperature in Pupfish Eggs.

PubMed

Jones, Alexander C; Lim, David; Wayne-Thompson, Jacoby J; Urbina, Natasha; Puentedura, Georgina; Hillyard, Stanley; Breukelen, Frank Van

2016-10-01

The habitat of the critically endangered Devils Hole Pupfish, Cyprinodon diabolis is marked by constant high temperatures and low oxygen availability. In order to explore the effects of these conditions on development and recruitment of eggs in Devils Hole, we tested the effects of two ecologically relevant temperatures on the development, hatch success, and oxygen consumption of eggs from a refuge population of pupfish derived from C. diabolis and eggs from its close sister species, Cyprinodon nevadensis mionectes. We developed a simple method to measure oxygen consumption in a single egg. Parent acclimation temperature, rather than incubation temperature, was the most important factor influencing hatch success. Eggs incubated at 33°C hatched more quickly compared to those incubated at 28°C. Despite this accelerated development, larvae from both temperatures were of similar size at hatch. Unexpectedly, eggs incubated at 33°C experience lower than expected oxygen consumption rates compared to those incubated at 28°C. Oxygen consumption rates would be limited at PO 2 values that are much higher than environmental oxygen tensions. Oxygen consumption increased dramatically upon hatch, indicating that low oxygen conditions such as those present in Devils Hole may limit developing eggs. © 2016 Wiley Periodicals, Inc.

Identifying pelagic fish eggs in the southeast Yucatan Peninsula using DNA barcodes.

PubMed

Leyva-Cruz, E; Vásquez-Yeomans, L; Carrillo, L; Valdez-Moreno, M

2016-12-01

In the waters surrounding Banco Chinchorro in the Mexican Caribbean are spawning and nursery areas for many types of fish. In this natural environment, as opposed to under controlled laboratory conditions, it is almost impossible to link an individual egg to the adult that laid it. This makes identifying the species of the eggs difficult. However, DNA barcodes have made this easier. In the present study, 300 eggs were processed for molecular analysis, from which 139 sequences were obtained. We identified 42 taxa (33 species with their binomial names), 35 genera, and 24 families. The identified eggs included those from Ariomma melanum, which is the first recording of this species in the Mexican Caribbean. Eggs from economically important fish species were also identified, including frigate tuna (Auxis thazard), crevalle jack (Caranx hippos), common dolphinfish (Coryphaena hippurus), sailfish (Istiophorus platypterus), white marlin (Kajikia albida), skipjack tuna (Katsuwonus pelamis), blackfin tuna (Thunnus atlanticus), and swordfish (Xiphias gladius). We have also described new morphological characteristics and captured photographs for 21 species, as well as obtained new information about spawning locality and time for 16 species. This valuable information will provide the basis to develop more effective conservation measures for sustainable fisheries and protection of the Mesoamerican Barrier Reef System.

Utility of component diagnostic testing in guiding oral food challenges to milk and egg.

PubMed

Wang, Julie

2016-11-01

Food allergies affect up to 8% of children, and milk and egg allergies are the most common triggers. Accurately diagnosing these food allergies is important to prevent allergic reactions and to avoid unnecessary dietary restrictions. However, positive skin-prick tests and detectable levels of serum food specific immunoglobulin E (IgE) alone may not be diagnostic for food allergy. Advances in the identification of relevant allergens and the development of recombinant proteins now allow assessment of IgE binding to individual proteins within a food. Component-resolved diagnostics (CRD) have the potential to provide more accurate assessments of clinical reactivity to food allergens. To examine the available data for CRD for milk and egg allergies. This review discussed studies that evaluated the utility of CRD for guiding decisions about food challenges for milk and egg. Results of studies indicated that CRD may offer increased specificity, but sensitivity was lacking when compared with standard skin-prick testing and measurement of serum food specific IgE levels. The role of CRD in the diagnosis and management of milk and egg allergies is not well established at this time. Further studies are needed to explore the diagnostic value of CRD for milk and egg allergies.

Abiotic factors influencing embryonic development, egg hatching, and larval orientation in the reindeer warble fly, Hypoderma tarandi.

PubMed

Karter, A J; Folstad, I; Anderson, J R

1992-10-01

Wild-caught, tethered females of the reindeer warble fly, Hypoderma tarandi (L.) (= Oedemagena tarandi (L.)), (Diptera, Oestridae) were stimulated to oviposit on hairs of a reindeer hide. Newly laid eggs incubated at constant temperatures and relative humidities hatched within 3 days to 2 weeks, depending on the experimental conditions. Over a range of 7-40 degrees C, hatching only occurred between 20 and 37 degrees C. Eggs held at 100% relative humidity had lower hatchability and longer time to hatch relative to eggs held at 77% relative humidity. The average number of degree-days for hatching was 50.35. Between 20 and 33 degrees C there was a temperature-dependent linear trend in developmental rate, and the proportion of eggs hatching was highest, and least variable, at the mid-temperature ranges. The temperature range found in the natural host micro-habitat where H. tarandi commonly affix their eggs (close to the skin at the base of a host hair) was consistent with the experimental temperature treatments that produced the highest hatching rate. Newly emerged larvae displayed positive thermotaxis, while showing no phototaxic or geotaxic behaviour. Results indicate that constraints of the host environment, coupled with temperature-dependent hatching success, may impose a selective pressure on oviposition behaviour.

Yolk formation in some Charadriiform birds

USGS Publications Warehouse

Roudybush, T.E.; Grau, C.R.; Petersen, M.R.; Ainley, D.G.; Hirsch, K.V.; Gilman, A.P.; Patten, S.M.

1979-01-01

By counting and measuring the major ova of breeding birds at autopsy and combining these data with time intervals between ovipositions, rough estimates have been made of the time required to form yolk in some non-captive birds (King 1973). Direct studies have been made in domestic fowl (Gallus gallus var. domesticus; Gilbert 1972), turkeys (Meleagris galloparvo; Bacon and Cherms 1968), and Common quail (Coturnix coturnix; Bacon and Koontz 1971), by feeding the birds a capsule containing dye each day, and counting dye rings in the yolks after the eggs have been hardcooked. Recently developed methods of fixing and staining eggs have revealed differences in yolk deposited during day and night, thus permitting another estimation of the number of days during which yolk was deposited, and without direct contact with the female (Grau 1976). In eggs from chickens and quail that have been fed dyes, yolk that stained darkly with dichromate was shown to be deposited during the active daytime feeding periods, while pale-staining yolk was deposited during the night. Thus, pairs of light and dark rings, which together take a day to be deposited, may be counted to estimate time of yolk formation.In the present study we have applied the yolk ring method of estimating the number of days during which the bulk of the yolk is deposited around the central white core (Grau 1976) to the eggs of some shorebirds, gulls, terns and alcids.

Population Development of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) under Simulated UK Glasshouse Conditions

PubMed Central

Cuthbertson, Andrew G.S.; Mathers, James J.; Blackburn, Lisa F.; Korycinska, Anastasia; Luo, Weiqi; Jacobson, Robert J.; Northing, Phil

2013-01-01

Tomato leafminer Tuta absoluta (Meyrick) is a major pest of tomato plants in South America. It was first recorded in the UK in 2009 where it has been subjected to eradication policies. The current work outlines T. absoluta development under various UK glasshouse temperatures. The optimum temperature for Tuta development ranged from 19–23 °C. At 19 °C, there was 52% survival of T. absoluta from egg to adult. As temperature increased (23 °C and above) development time of the moth would appear to decrease. Population development ceases between 7 and 10 °C. Only 17% of eggs hatched at 10 °C but no larvae developed through to adult moths. No eggs hatched when maintained at 7 °C. Under laboratory conditions the total lifespan of the moth was longest (72 days) at 13 °C and shortest (35 days) at both 23 and 25 °C. Development from egg to adult took 58 days at 13 °C; 37 days at 19 °C and 23 days at 25 °C. High mortality of larvae occurred under all temperatures tested. First instar larvae were exposed on the leaf surface for approximately 82 minutes before fully tunnelling into the leaf. Adult longevity was longest at 10 °C with moths living for 40 days and shortest at 19 °C where they survived for 16 days. Generally more males than females were produced. The potential of Tuta absoluta to establish populations within UK protected horticulture is discussed. PMID:26464384

Some correlations between development and respiration in the sand dollar egg, as shown by cyanide inhibition studies.

PubMed

ROBBIE, W A

1948-01-30

Cyanide is a valuable tool for studying respiratory mechanisms and their rôle in embryonic development: it is relatively specific in its action, penetrates cell membranes readily, is active in low concentration, and may be controlled quantitatively (page 217). Echinarachnius is extremely sensitive to cyanide and the oxygen consumption of both eggs and of sperm is almost completely inhibited by 10(-5)M HCN (pages 219 and 221). Cell division is likewise arrested by the same concentration (page 223). One of the pronounced effects of an irreversible dosage of cyanide is the marked cytolysis or breakdown of the egg, both internally and at the cell membrane. This cytolysis appears to be related to the state of metabolism, and its occurrence varies with both the respiratory and developmental activity of the cell (page 224). The lethal dosage of cyanide varies with the state of development of the egg: the unfertilized egg is less susceptible than the fertilized one, and the susceptibility increases as the development of the fertilized egg proceeds (page 228). The Echinarachnius egg differs from that of Arbacia in respiratory behavior chiefly in its inability to survive prolonged anoxia: the sea urchin egg will tolerate for 24 hours a concentration of cyanide that kills the sand dollar eggs in 30 minutes (page 229). The Echinarachnius egg is apparently completely dependent upon cyanide-sensitive catalytic systems for its normal functioning and maintenance. Interference with this aerobic energy release mechanism results in irreversible damage to the egg (page 231).

SOME CORRELATIONS BETWEEN DEVELOPMENT AND RESPIRATION IN THE SAND DOLLAR EGG, AS SHOWN BY CYANIDE INHIBITION STUDIES

PubMed Central

Robbie, W. A.

1948-01-01

Cyanide is a valuable tool for studying respiratory mechanisms and their rôle in embryonic development: it is relatively specific in its action, penetrates cell membranes readily, is active in low concentration, and may be controlled quantitatively (page 217). Echinarachnius is extremely sensitive to cyanide and the oxygen consumption of both eggs and of sperm is almost completely inhibited by 10–5 M HCN (pages 219 and 221). Cell division is likewise arrested by the same concentration (page 223). One of the pronounced effects of an irreversible dosage of cyanide is the marked cytolysis or breakdown of the egg, both internally and at the cell membrane. This cytolysis appears to be related to the state of metabolism, and its occurrence varies with both the respiratory and developmental activity of the cell (page 224). The lethal dosage of cyanide varies with the state of development of the egg: the unfertilized egg is less susceptible than the fertilized one, and the susceptibility increases as the development of the fertilized egg proceeds (page 228). The Echinarachnius egg differs from that of Arbacia in respiratory behavior chiefly in its inability to survive prolonged anoxia: the sea urchin egg will tolerate for 24 hours a concentration of cyanide that kills the sand dollar eggs in 30 minutes (page 229). The Echinarachnius egg is apparently completely dependent upon cyanide-sensitive catalytic systems for its normal functioning and maintenance. Interference with this aerobic energy release mechanism results in irreversible damage to the egg (page 231). PMID:18920609

Cholecystolithiasis Is Associated with Clonorchis sinensis Infection

PubMed Central

Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Luo, Zhen-liang; Zheng, Pei-ming

2012-01-01

Background The objective of this study was to analyze gallbladder stones for direct evidence of a relationship between Clonorchis sinensis infection and gallbladder stones formation. Methodology We investigated one hundred eighty-three gallbladder stones for the presence of Clonorchis sinensis eggs using microscopy, and analyzed their composition using Fourier transform infrared spectroscopy. We confirmed the presence of Clonorchis sinensis eggs in the gallbladder stones using real-time fluorescent PCR and scanning electron microscopy. Principal Findings Clonorchis sinensis eggs were detected in 122 of 183 gallbladder stones based on morphologic characteristics and results from real-time fluorescent PCR. The proportion of pigment stones, cholesterol stones and mixed gallstones in the egg-positive stones was 79.5% (97/122), 3.3% (4/122) and 17.2% (21/122), respectively, while 29.5% (18/61), 31.1% (19/61) and 39.3% (24/61) in the egg-negative stones. The proportion of pigment stone in the Clonorchis sinensis egg-positive stones was higher than in egg-negative stones (P<0.0001). In the 30 egg-positive stones examined by scanning electron microscopy, dozens or even hundreds of Clonorchis sinensis eggs were visible (×400) showing a distinct morphology. Many eggs were wrapped with surrounding particles, and in some, muskmelon wrinkles was seen on the surface of the eggs. Also visible were pieces of texture shed from some of the eggs. Some eggs were depressed or without operculum while most eggs were adhered to or wrapped with amorphous particles or mucoid matter (×3000). Conclusion Clonorchis sinensis eggs were detected in the gallbladder stones which suggests an association between Clonorchis sinensis infection and gallbladder stones formation, especially pigment stones. PMID:22905137

9 CFR 590.122 - Time of inspection.

Code of Federal Regulations, 2010 CFR

2010-01-01

... shall be given reasonable advance notice by plant management of the hours when such inspection will be... PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Performance of...

Validation of Folate-Enriched Eggs as a Functional Food for Improving Folate Intake in Consumers

PubMed Central

Altic, Leslie; McNulty, Helene; Hoey, Leane; McAnena, Liadhan; Pentieva, Kristina

2016-01-01

Functional foods enriched with folate may be beneficial as a means of optimizing folate status in consumers. We recently developed novel eggs enriched with folate through folic acid supplementation of the hen’s feed, but their potential to influence consumer folate status is unknown because the natural folate forms incorporated into the eggs may not necessarily be retained during storage and cooking. This study aimed to determine the stability of natural folates in folate-enriched eggs under typical conditions of storage and cooking. Total folate was determined by microbiological assay following tri-enzyme treatment in folate-enriched eggs and un-enriched (barn and free-range) on the day they were laid, after storage (up to 27 days) and after using four typical cooking methods (boiling, poaching, frying, scrambling) for different durations. On the day of laying, the folate content of enriched eggs was found to be significantly higher than that of un-enriched barn or free-range eggs (mean ± SD; 123.2 ± 12.4 vs. 41.2 ± 2.8 vs. 65.6 ± 18.5 µg/100 g; p < 0.001). Storage at refrigerator and room temperature for periods up to the Best Before date resulted in no significant losses to the folate content of folate-enriched eggs. Furthermore, folate in enriched eggs remained stable when cooked by four typical methods for periods up to the maximum cooking time (e.g., 135 ± 22.5, 133.9 ± 23.0 and 132.5 ± 35.1; p = 0.73, for raw, scrambled for 50 s and scrambled for 2 min, respectively). Thus, natural folates in folate-enriched eggs remain highly stable with little or no losses following storage and cooking. These findings are important because they demonstrate the feasibility of introducing folate-enriched eggs into the diet of consumers as functional foods with enriched folate content. Further studies will confirm their effectiveness in optimizing the biomarker folate status of consumers. PMID:27916895

Validation of Folate-Enriched Eggs as a Functional Food for Improving Folate Intake in Consumers.

PubMed

Altic, Leslie; McNulty, Helene; Hoey, Leane; McAnena, Liadhan; Pentieva, Kristina

2016-11-30

Functional foods enriched with folate may be beneficial as a means of optimizing folate status in consumers. We recently developed novel eggs enriched with folate through folic acid supplementation of the hen's feed, but their potential to influence consumer folate status is unknown because the natural folate forms incorporated into the eggs may not necessarily be retained during storage and cooking. This study aimed to determine the stability of natural folates in folate-enriched eggs under typical conditions of storage and cooking. Total folate was determined by microbiological assay following tri-enzyme treatment in folate-enriched eggs and un-enriched (barn and free-range) on the day they were laid, after storage (up to 27 days) and after using four typical cooking methods (boiling, poaching, frying, scrambling) for different durations. On the day of laying, the folate content of enriched eggs was found to be significantly higher than that of un-enriched barn or free-range eggs (mean ± SD; 123.2 ± 12.4 vs. 41.2 ± 2.8 vs. 65.6 ± 18.5 µg/100 g; p < 0.001). Storage at refrigerator and room temperature for periods up to the Best Before date resulted in no significant losses to the folate content of folate-enriched eggs. Furthermore, folate in enriched eggs remained stable when cooked by four typical methods for periods up to the maximum cooking time (e.g., 135 ± 22.5, 133.9 ± 23.0 and 132.5 ± 35.1; p = 0.73, for raw, scrambled for 50 s and scrambled for 2 min, respectively). Thus, natural folates in folate-enriched eggs remain highly stable with little or no losses following storage and cooking. These findings are important because they demonstrate the feasibility of introducing folate-enriched eggs into the diet of consumers as functional foods with enriched folate content. Further studies will confirm their effectiveness in optimizing the biomarker folate status of consumers.

Plasma dispositions and concentrations of ivermectin in eggs following treatment of laying hens.

PubMed

Cirak, V Y; Aksit, D; Cihan, H; Gokbulut, C

2018-05-01

To determine the plasma disposition and concentrations of ivermectin (IVM) in eggs produced by laying hens following S/C, oral and I/V administration. Twenty-four laying hens, aged 37 weeks and weighing 1.73 (SD 0.12) kg were allocated to three groups of eight birds. The injectable formulation of IVM was administered either orally, S/C, or I/V, at a dose of 0.2 mg/kg liveweight, following dilution (1:5, v/v) with propylene glycol. Heparinised blood samples were collected at various times between 0.25 hours and 20 days after drug administration. Eggs produced by hens were also collected daily throughout the study period. Samples of plasma and homogenised egg were analysed using HPLC. Maximum concentrations of IVM in plasma and mean residence time of IVM were lower after oral (10.2 (SD 7.2) ng/mL and 0.38 (SD 0.14) days, respectively) than after S/C (82.9 (SD 12.4) ng/mL and 1.05 (SD 0.24) days, respectively) administration (p<0.01). The time to maximum concentration and elimination half-life were shorter following oral (0.14 (SD 0.04) and 0.23 (SD 0.11) days, respectively) than S/C (0.25 (SD 0.00) and 1.45 (SD 0.45) days, respectively) administration (p<0.01). IVM was first detected in eggs 2 days after treatment in all groups and was detected until 8 days after oral and I/V administration, and until 15 days after S/C administration. Peak concentrations of IVM were 15.7, 23.3 and 1.9 µg/kg, observed 2, 5 and 4 days after I/V, S/C and oral administration, respectively. The low plasma bioavailability of IVM observed after oral administration in laying hens could result in lower efficacy or subtherapeutic plasma concentrations, which may promote the development of parasitic drug resistance. Due to high IVM residues in eggs compared to the maximum residue limits for other food-producing animal species, a withdrawal period should be necessary for eggs after IVM treatment in laying hens.

Toxicity of pesticide and fertilizer mixtures simulating corn production to eggs of snapping turtles (Chelydra serpentina).

PubMed

de Solla, Shane Raymond; Martin, Pamela Anne; Mikoda, Paul

2011-09-15

Many reptiles oviposit in soils associated with agricultural landscapes. We evaluated the toxicity of a pesticide and fertilizer regime similar to those used in corn production in Ontario on the survivorship of exposed snapping turtle (Chelydra serpentina) eggs. The herbicides atrazine, dimethenamid, and glyphosate, the pyrethroid insecticide tefluthrin, and the fertilizer ammonia, were applied to clean soil, both as partial mixtures within chemical classes, as well as complete mixtures. Eggs were incubated in the soil in a garden plot in which these mixtures were applied at a typical field application rate, and higher rates. Otherwise, the eggs were unmanipulated and were subject to ambient temperature and weather conditions. Eggs were also exposed at male producing temperatures in the laboratory in covered bins in the same soil, where there was less opportunity for loss through volatilization or leaching. Egg mortality was 100% at 10× the typical field application rate of the complete mixture, both with and without tefluthrin. At typical field application rates, hatching success ranged between 91.7 and 95.8%. Eggs exposed only to herbicides were not negatively affected at any application rates. Although fertilizer treatments at typical field application rates did not affect eggs, mortality was remarkably higher at three times this rate, and 100% at higher rates. The frequency of deformities of hatchlings was elevated at the highest application rate of the insecticide tefluthrin. The majority of the toxicity of the mixture was not due to the herbicides or insecticide, but was due to the ammonia fertilizer. At typical field application rates, the chemical regime associated with corn production does not appear to have any detrimental impacts upon turtle egg development; however toxicity dramatically increases if this threshold is passed. Copyright © 2011. Published by Elsevier B.V.

Direct application of geothermal energy at the L'eggs Product Plant, Las Cruces, New Mexico. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-02-01

The study program to determine the feasibility of interfacing a potential geothermal resource of Dona Ana County, New Mexico L'eggs Product industrial process is discussed in this final report. Five separate sites were evaluated initially as to geothermal potential and technical feasibility. Preliminary analysis revealed that three sites were considered normal, but that two sites (about three miles from the L'eggs Plant) had very high shallow subsurface temperature gradients (up to 14.85/sup 0/F/100 ft). An initial engineering analysis showed that to meet the L'eggs plant temperature and energy requirements a geothermal fluid temperature of about 250/sup 0/F and 200 gpmmore » flow rate would be necessary. A brief economic comparison indicated that the L'eggs plant site and a geothermal site approximately four miles from the plant did merit further investigation. Detailed engineering and economic design and analysis of these two sites (including the drilling of an 1873 feet deep temperature gradient test hole at the L'eggs Plant) showed that development of the four mile distant site was technically feasible and was the more economic option. It was determined that a single-stage flash system interface design would be most appropriate for the L'eggs Plant. Approximately 39 billion Btu/yr of fossil fuel could be replaced with geothermal energy at the L'eggs facility for a total installed system cost of slightly over $2 million. The projected economic payback period was calculated to be 9.2 years before taxes. This payback was not considered acceptable by L'eggs Products, Inc., to merit additional design or construction work at this time.« less

Improved egg crack detection algorithm for modified pressure imaging system

USDA-ARS?s Scientific Manuscript database

Shell eggs with microcracks are often undetected during egg grading processes. In the past, a modified pressure imaging system was developed to detect eggs with microcracks without adversely affecting the quality of normal intact eggs. The basic idea of the modified pressure imaging system was to ap...

Using a novel micro-sampling technique to monitor the effects of methylmercury on the eggs of wild birds

USGS Publications Warehouse

Klimstra, J.D.; Stebbins, K.R.; Heinz, G.H.

2007-01-01

Methylmercury is the predominant chemical form of mercury reported in the eggs of wild birds. The embryo is the life stage at which birds are most sensitive to methylmercury. Protective guidelines have been based largely on captive-breeding studies done with chickens (Gallus domesticus), mallards (Anas platyrhynchos), and ring-necked pheasants (Phasianus colchicus). Typically these studies are cost and time prohibitive. In the past, researchers have used either egg injections or the ?sample egg? technique to determine contaminant effects on bird eggs. Both techniques have their limitations. As an alternative to the above methods and because most of the methylmercury is found in the albumen we have developed a novel, less invasive technique, to micro-sample the albumen of eggs in the field. An albumen sample would be analyzed and then compared to the hatching success of that egg. Using the micro-sampling procedure, the egg is oriented with the blunt end up and the pointed end down. A vent hole is drilled at the top to relieve pressure. Approximately one third up from the bottom, a withdrawal site is drilled just until the inner shell membrane is exposed. A syringe with a 21 or 18 gauge needle is gently inserted just into the egg and approximately 200?300?l of albumen is removed. Almost concurrently this site and then the vent are sealed. Thus far we have experimented with both chicken and mallard eggs in the laboratory. We sampled chicken eggs at days 0 and 3 of incubation with a hatching success of 76% and 70%, respectively. Neither group was significantly different from control eggs (P=0.52, 0.54). Field studies are in progress using this technique in which birds are allowed to incubate their own eggs. We envision micro-sampling to be a tool that researchers and managers could use in the field to determine the effects of mercury or other contaminants in bird populations. Micro-sampling would reduce the impact on the sampled population and could be used to monitor sensitive species without impacting reproduction and recruitment.

Extreme intra-clutch egg size dimorphism is not coupled with corresponding differences in antioxidant capacity and stable isotopes between eggs.

PubMed

Poisbleau, Maud; Beaulieu, Michaël; Dehnhard, Nina; Demongin, Laurent; Lepoint, Gilles; Sturaro, Nicolas; Eens, Marcel

2017-03-01

Oviparous females need to allocate resources optimally to their eggs in order to maximize their fitness. Among these resources, dietary antioxidants, acquired by females and transferred to the eggs during egg formation, can greatly affect the development and survival of the embryo and chick. In crested penguins, incubation starts after the second and last egg is laid and, as opposed to many other bird species, this egg hatches first, thereby enhancing the survival of the chick. Here, we assessed whether antioxidant and isotopic composition could underlie these differences between eggs within clutches of southern rockhopper penguins (Eudyptes chrysocome chrysocome). The second-laid egg had higher total antioxidant capacity than the first-laid egg, although this was not due to higher antioxidant concentration but to its higher mass. This suggests that resources are allocated by females at a constant rate in both eggs within clutches. Accordingly, we found a strong correlation for isotopic compositions between eggs suggesting that resources were allocated similarly to each egg within the clutch. Overall, we found little evidence for a significant role of antioxidant and isotopic compositions to explain differences in terms of embryo/chick development between eggs in crested penguins. However, since our results suggest a constant rate of antioxidant transfer from females to eggs, limiting the mass of the first-laid egg might represent a strategy for females to spare antioxidant defences and preserve self-maintenance. Copyright © 2017 Elsevier Inc. All rights reserved.

DEVELOPMENTAL PATTERN AND ADAPTATIONS FOR REPRODUCTION IN NUCELLA CRASSILABRUM AND OTHER MURICACEAN GASTROPODS.

PubMed

Gallardo, C S

1979-12-01

1. Eggs of Nucella crassilabrum range from 204 to 293 µm in diameter (mean = 240 µm). Only 6.6 to 7.9% are fertile; the remaining are ingested as nurse eggs. 2. Embryos metamorphose before hatching. Pre-hatching time ranges from 55 to 80 days according to seasonal temperature fluctuations. 3. Hatching size varies from 0.82 to 1.3 mm, depending on number of nurse-eggs ingested per embryo (from 3 to 20). Number of fertile embryos per capsule (10 to 122) depends on capsule size. 4. Hatching type and hatching size shown by N. crassilabrum agree with those of other muricaceans living in similar habitat conditions. 5. Pre-hatching time and hatching size data of various muricaceans are analyzed to determine to what extent they influence embryonic mode of nutrition, namely the presence of nurse-eggs or alternatively large and fertile self-sufficient eggs. Provision of nurse-eggs for embryos is of common occurrence among intertidal muricaceans and this mode of nutrition seems to have been favored in such habitats to reduce developmental time. Providing the yolk as nurse-eggs seems also to contribute to a larger hatching size, as suggested by some subtidal muricaceans with such embryo support patterns.

Applications of immunomagnetic capture and time-resolved fluorescence detection for Salmonella enteriditis in liquid eggs

NASA Astrophysics Data System (ADS)

Tu, Shu-I.; Gehring, Andrew; Paoli, George

2008-04-01

An immuno sandwich method was evaluated for the detection of Salmonella in liquid eggs. Liquid eggs spiked with different out-break strains of Salmonella were mixed with proper enrichment media and incubated at 37 C for 4 to 20 h. After enrichment, immunomagnetic beads (IMB) coated with anti Salmonella antibodies were used to capture the bacteria. Samarium (Sm) labeled anti Salmonella antibodies were then used to form sandwiched complexes with IMB captured bacteria. Sandwiched Salmonella were then treated with Sm-chelator to allow the measurement of the released Sm by time-resolved fluorescence (TRF). The processes ranging from IMB capture to Sm chelation were performed using an automated KingFisher apparatus. With this approach, the presence of ~ 1 CFU of outbreak strains of Salmonella Enteritidis per egg (~50 g of liquid eggs) could be detected after enrichment for 20 h at 37 C. For higher levels of Salmonella Enteritidis contamination, e.g., 10 CFU per 50 g of liquid eggs, the enrichment time could be reduced to 5 h at 37 C. The results demonstrated that a combination of IMB capture and TRF measurement could be a rapid and sensitive method for Salmonella Enteritidis detection in liquid eggs.

The effect of space environment on the development and aging of Drosophila Melanogaster (7-IML-1)

NASA Technical Reports Server (NTRS)

Marco, Roberto

1992-01-01

This experiment involves the study of the development of eggs of the fly, Drosophila, exposed to microgravity. It is presumed that oogenesis, rather than further states of embryonic development, is sensitive to gravity. This hypothesis will be tested by collecting eggs layered at specific times inflight and postflight from flies exposed to 0 and 1 g. This portion of the experiment is a repetition of an earlier experiment flown in Biorack during the Spacelab D1 Mission. An added feature of the experiment for the First International Microgravity Laboratory (IML-1) Mission is to study the effect of microgravity on the life span of Drosophila male flies. Various aspects of the investigation are discussed.

Population Growth Potential of the Bed Bug, Cimex lectularius L.: A Life Table Analysis

PubMed Central

Polanco, Andrea M.; Brewster, Carlyle C.; Miller, Dini M.

2011-01-01

Experimental life tables were constructed and analyzed for three strains of the common bed bug: a pyrethroid-susceptible laboratory strain (HS), a highly resistant field strain (RR), and a field strain with a declining level of resistance (KR). Egg to adult survival in the RR strain was 94% compared with 79% and 69% in the HS and KR strains, respectively. The RR strain also developed significantly faster from egg to adult (∼35 days) than the other two strains (∼40 days). Analysis of a survivorship and fecundity life table for the RR strain produced the following results. The average life expectancy for a newly laid egg was ∼143 days, and that of a newly molted adult was ∼127 days. Females produced an average of 0.64 daughter eggs/day with the highest weekly production during the fifth week of adult life. Analysis of daily reproductive parity showed that females produced 1–3 and 4–6 eggs on 79 and 21% of the days, respectively, when egg laying occurred. The net reproductive rate (R0) of the RR strain was ∼35, which represents a 35-fold increase in the population per generation (∼92 days). The intrinsic rate of increase, r, was 0.054 indicating that the population multiplies 1.1 times/female/day (λ) and doubles in size every 13 days. The stable age distribution (cx) was dominated by nymphs (54%), followed by eggs (34%) and adults (12%). Reproductive values (vx) for the strain increased from egg to the adult stage. PMID:26467620

Evaluation of suspension array analysis for detection of egg yolk antibodies against Salmonella Enteritidis.

PubMed

Thomas, M E; Klinkenberg, D; Bergwerff, A A; van Eerden, E; Stegeman, J A; Bouma, A

2010-06-01

Salmonella enterica serovar Enteritidis (SE) is an important source of food-related diarrhoea in humans, and table eggs are considered the primordial source of contamination of the human food chain. Using eggs collected at egg-packing stations as samples could be a convenient strategy to detect colonization of layer flocks. The aim of this study was to evaluate egg yolk anti-Salmonella antibody detection using suspension array analysis. An egg yolk panel from contact-infected and non-colonized laying hens was used for the evaluation. Receiver Operating Characteristic (ROC) curves were generated to define a cut-off value and to assess the overall accuracy of the assay. The diagnostic sensitivity and specificity were estimated by maximum likelihood. Sensitivity was quantified on hen level and on sample level, and also quantified as a function of time since colonization. The area under the ROC curve was estimated at 0.984 (se 0.006, P<0.001). Of all colonized contact-infected hens, 67.6% [95% CI: 46.8, 100] developed an antibody response, which was detectable 17.4 days [14.3, 26.9] after colonization. In total, 98% [95.4, 99.4] of the 'immunopositive' hens had test positive eggs. The overall sensitivity of the immunological test was 66.7% [45.9, 98.7] and the specificity was 98.5% [97.8, 99.1]. This study provided essential parameters for optimizing surveillance programs based on detection of antibodies, and indicates that immunology based on examination of egg yolk gives important information about the Salmonella status of the flock. (c) 2010 Elsevier B.V. All rights reserved.

Determinants and taxonomic consequences of extreme egg shell variability in Ramazzottius subanomalus (Biserov, 1985) (Tardigrada).

PubMed

Stec, Daniel; Morek, Witold; Gąsiorek, Piotr; Kaczmarek, Łukasz; Michalczyk, Łukasz

2016-12-15

Nearly a half of known eutardigrade species lay ornamented eggs. The ornamentation is thought to provide attachment of the egg to the substrate and protection for the developing embryo, but from the taxonomic point of view chorion morphology may also provide key characters for species differentiation and identification, especially between closely related taxa. Nonetheless, despite the evolutionary and taxonomic importance of the egg shell, the determinants of its morphology are very poorly, if at all, understood. Here, we combine morphological, molecular and experimental approaches in an attempt to separate the genetic and environmental factors that shape egg chorion morphology in Ramazzottius subanomalus (Biserov, 1985). Our integrative study, based on a population of R. subanomalus isolated from a single moss sample, revealed (1) remarkable variation in egg shell morphology, but (2) relatively little variation in animal morphometric traits, and (3) genetic differentiation, expressed as two ITS-2 haplotypes, but no parallel polymorphism in COI. Although animals did not differ morphometrically between the haplotypes, eggs laid by haplotype 1 and 2 females exhibited highly statistically significant differences in all measured traits. The study demonstrates, for the first time, a correlation between phenotypic and genetic variability within a tardigrade species. The revealed congruence between genetic and morphological traits might be viewed as an example of incipient speciation that illustrates early evolutionary steps leading to species complexes that differ primarily in terms of egg shell morphology. Moreover, our data confirm the value of the ITS-2 fragment in distinguishing very closely related tardigrade lineages.

Effects of flour conditioning on cannibalism of T. castaneum eggs and pupae.

PubMed

Flinn, Paul W; Campbell, James F

2012-12-01

Cannibalism is a very important factor regulating population dynamics of the red flour beetle. After several days of feeding, the flour becomes conditioned by the beetles, which can affect rates of cannibalism. Flour conditioning is caused by an accumulation of feces, pheromones, and ethylquinone, which is a repellent produced by the beetles. We determined the effect of five different levels of flour conditioning on cannibalism of red flour beetle eggs and pupae by adult and larval stages. Larvae had the highest rates of egg cannibalism (12 eggs eaten over the 4-d period) followed by female adults (seven eggs consumed). Adult males had the lowest rates of cannibalism with only two eggs consumed. Cannibalism of eggs by females was correlated negatively with the level of flour conditioning. There was no effect of flour conditioning on egg or pupal cannibalism by larvae or adult males. Cannibalism by adult females may decrease as the level of flour conditioning increases because females may spend less time tunneling in highly conditioned flour and more time trying to disperse to other areas that are better for oviposition.

Challenges in Radiofrequency Pasteurization of Shell Eggs: Coagulation Rings.

PubMed

Lau, Soon Kiat; Thippareddi, Harshavardhan; Jones, David; Negahban, Mehrdad; Subbiah, Jeyamkondan

2016-10-01

A total of 50 different configurations of simple radiofrequency (RF) heating at 27.12 MHz of a shell egg were simulated using a finite element model with the purpose of pasteurizing the egg. Temperature-dependent thermal and dielectric properties of the yolk, albumen, and shell were measured, fitted, and introduced into the model. A regression equation that relates the top electrode voltage to the gap between the electrodes and vertical position of the egg was developed. Simulation and experimental results had good agreement in terms of temperature deviation (root mean squared error ranged from 0.35 °C to 0.48 °C) and both results demonstrated the development of a "coagulation ring" around the air cell. The focused heating near the air cell of the egg prevented pasteurization of the egg due to its impact on quality (coagulation). Analysis of the electric field patterns offered a perspective on how nonuniform RF heating could occur in heterogeneous food products. The results can be used to guide development of RF heating for heterogeneous food products and further development of RF pasteurization of eggs. © 2016 Institute of Food Technologists®.

Insecticidal activity of 2-tridecanone against the cowpea weevil Callosobruchus maculatus (Coleoptera: Bruchidae).

PubMed

Braga, Yussef F B; Grangeiro, Thalles B; Freire, Eder A; Lopes, Helano L; Bezerra, José N S; Andrade-Neto, Manoel; Lima, Mary Anne S

2007-03-01

The effect of 2-tridecanone vapor on the cowpea weevil (Callosobruchus maculatus) development was determined. Seeds of cowpea were infested with adults and exposed to different doses of 2-tridecanone isolated from Pilocarpus microphyllus Stapf ex Holm, a plant species native from northeastern Brazil. The pure monoterpene was evaluated both undiluted as well as in the dilutions 1:10, 1:100 and 1:1,000 (v/v). The following parameters of the cowpea weevil life cycle were analyzed in response to decreasing doses of 2-tridecanone: number of eggs laid, percentage of egg hatching on seeds, percentage of adult emergence, adult weight at emergence, mean developmental time and number of adults emerged. Vapor of 2-tridecanone caused a significant (P < 0.05) reduction in the number of eggs laid, in the percentage of eggs hatched and in the number of emerged adults in infested seeds. The fumigant insecticidal effect of 2-tridecanone was mainly due to its ovicidal activity.

DNA extraction and barcode identification of development stages of forensically important flies in the Czech Republic.

PubMed

Olekšáková, Tereza; Žurovcová, Martina; Klimešová, Vanda; Barták, Miroslav; Šuláková, Hana

2018-04-01

Several methods of DNA extraction, coupled with 'DNA barcoding' species identification, were compared using specimens from early developmental stages of forensically important flies from the Calliphoridae and Sarcophagidae families. DNA was extracted at three immature stages - eggs, the first instar larvae, and empty pupal cases (puparia) - using four different extraction methods, namely, one simple 'homemade' extraction buffer protocol and three commercial kits. The extraction conditions, including the amount of proteinase K and incubation times, were optimized. The simple extraction buffer method was successful for half of the eggs and for the first instar larval samples. The DNA Lego Kit and DEP-25 DNA Extraction Kit were useful for DNA extractions from the first instar larvae samples, and the DNA Lego Kit was also successful regarding the extraction from eggs. The QIAamp DNA mini kit was the most effective; the extraction was successful with regard to all sample types - eggs, larvae, and pupari.

O-polysaccharide is important for Salmonella Pullorum survival in egg albumen, and virulence and colonization in chicken embryos.

PubMed

Guo, Rongxian; Li, Zhuoyang; Jiao, Yang; Geng, Shizhong; Pan, Zhiming; Chen, Xiang; Li, Qiuchun; Jiao, Xinan

2017-10-01

The pathogen Salmonella Pullorum is the causative agent of persistent systemic infection of poultry, leading to economic losses in developing countries due to morbidity, mortality and reduction in egg production. These infections may result in vertical transmission to eggs or progeny. Limited information is available regarding the mechanisms involved in the survival of Salmonella Pullorum in egg albumen and developing chicken embryos. Hence, we investigated the role of O-polysaccharide in the contamination of eggs and the colonization of chicken embryos. Compared with the wild-type strain, the isogenic waaL mutant exhibited an O-antigen-deficient rough phenotype, and increased sensitivity to egg albumen and chicken serum, as well as reduced adherence to DF-1 cells. Infection with Salmonella Pullorum lacking O-polysaccharide resulted in significantly reduced embryo lethality and bacterial colonization. These results suggest that O-polysaccharide is essential for Salmonella Pullorum colonization in eggs, both post-lay and developing embryos. The chicken embryo infection model could be used to characterize the interaction between Salmonella Pullorum and developing embryos, and it will also contribute to the development of more rational vaccines to protect laying hens and embryos.

Time-limited environments affect the evolution of egg-body size allometry.

PubMed

Eckerström-Liedholm, Simon; Sowersby, Will; Gonzalez-Voyer, Alejandro; Rogell, Björn

2017-07-01

Initial offspring size is a fundamental component of absolute growth rate, where large offspring will reach a given adult body size faster than smaller offspring. Yet, our knowledge regarding the coevolution between offspring and adult size is limited. In time-constrained environments, organisms need to reproduce at a high rate and reach a reproductive size quickly. To rapidly attain a large adult body size, we hypothesize that, in seasonal habitats, large species are bound to having a large initial size, and consequently, the evolution of egg size will be tightly matched to that of body size, compared to less time-limited systems. We tested this hypothesis in killifishes, and found a significantly steeper allometric relationship between egg and body sizes in annual, compared to nonannual species. We also found higher rates of evolution of egg and body size in annual compared to nonannual species. Our results suggest that time-constrained environments impose strong selection on rapidly reaching a species-specific body size, and reproduce at a high rate, which in turn imposes constraints on the evolution of egg sizes. In combination, these distinct selection pressures result in different relationships between egg and body size among species in time-constrained versus permanent habitats. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Laying sequence interacts with incubation temperature to influence rate of embryonic development and hatching synchrony in a precocial bird.

PubMed

Hepp, Gary R; Kennamer, Robert A

2018-01-01

Incubation starts during egg laying for many bird species and causes developmental asynchrony within clutches. Faster development of late-laid eggs can help reduce developmental differences and synchronize hatching, which is important for precocial species whose young must leave the nest soon after hatching. In this study, we examined the effect of egg laying sequence on length of the incubation period in Wood Ducks (Aix sponsa). Because incubation temperature strongly influences embryonic development rates, we tested the interactive effects of laying sequence and incubation temperature on the ability of late-laid eggs to accelerate development and synchronize hatching. We also examined the potential cost of faster development on duckling body condition. Fresh eggs were collected and incubated at three biologically relevant temperatures (Low: 34.9°C, Medium: 35.8°C, and High: 37.6°C), and egg laying sequences from 1 to 12 were used. Length of the incubation period declined linearly as laying sequence advanced, but the relationship was strongest at medium temperatures followed by low temperatures and high temperatures. There was little support for including fresh egg mass in models of incubation period. Estimated differences in length of the incubation period between eggs 1 and 12 were 2.7 d, 1.2 d, and 0.7 d at medium, low and high temperatures, respectively. Only at intermediate incubation temperatures did development rates of late-laid eggs increase sufficiently to completely compensate for natural levels of developmental asynchrony that have been reported in Wood Duck clutches at the start of full incubation. Body condition of ducklings was strongly affected by fresh egg mass and incubation temperature but declined only slightly as laying sequence progressed. Our findings show that laying sequence and incubation temperature play important roles in helping to shape embryo development and hatching synchrony in a precocial bird.

Laying sequence interacts with incubation temperature to influence rate of embryonic development and hatching synchrony in a precocial bird

PubMed Central

Kennamer, Robert A.

2018-01-01

Incubation starts during egg laying for many bird species and causes developmental asynchrony within clutches. Faster development of late-laid eggs can help reduce developmental differences and synchronize hatching, which is important for precocial species whose young must leave the nest soon after hatching. In this study, we examined the effect of egg laying sequence on length of the incubation period in Wood Ducks (Aix sponsa). Because incubation temperature strongly influences embryonic development rates, we tested the interactive effects of laying sequence and incubation temperature on the ability of late-laid eggs to accelerate development and synchronize hatching. We also examined the potential cost of faster development on duckling body condition. Fresh eggs were collected and incubated at three biologically relevant temperatures (Low: 34.9°C, Medium: 35.8°C, and High: 37.6°C), and egg laying sequences from 1 to 12 were used. Length of the incubation period declined linearly as laying sequence advanced, but the relationship was strongest at medium temperatures followed by low temperatures and high temperatures. There was little support for including fresh egg mass in models of incubation period. Estimated differences in length of the incubation period between eggs 1 and 12 were 2.7 d, 1.2 d, and 0.7 d at medium, low and high temperatures, respectively. Only at intermediate incubation temperatures did development rates of late-laid eggs increase sufficiently to completely compensate for natural levels of developmental asynchrony that have been reported in Wood Duck clutches at the start of full incubation. Body condition of ducklings was strongly affected by fresh egg mass and incubation temperature but declined only slightly as laying sequence progressed. Our findings show that laying sequence and incubation temperature play important roles in helping to shape embryo development and hatching synchrony in a precocial bird. PMID:29373593

Rheological behaviour of egg white and egg yolk from different poultry specimen

NASA Astrophysics Data System (ADS)

Kumbár, V.; Nedomová, Š.; Votava, J.; Buchar, J.

2017-01-01

The main goal of this study is differences in rheological behaviour of hen (ISA BROWN), goose (Anser anser f. domestica) and Japanese quail (Coturnix japonica) egg white and egg yolk. The rheological behaviour of egg white and egg yolk was studied using a concentric cylinder viscometer. Rheological behaviour was pseudoplastic and flow curves were fitted by the Herschel-Bulkley model and Ostwald-de Waele model with high values of coeficients of determination R2. The meaning of rheological parameters on friction factors during flow of egg white and egg yolk in real tube has been shown. Preliminary information on time-dependent behaviour of tested liquids has been also obtained.

[Effects of pomegranate varieties on the development and fecundity of Assara inouei Yamanaka (Lepidoptera: Pyralidae)].

PubMed

He, Chao; Shen, Deng Rong; Yin, Li Hong; Li, Xi Liang; He, Jian Cai; Yuan, Sheng Yong; Tian, Xue Jun

2017-03-18

Assara inouei Yanmanaka is an important pest of pomegranate fruits in Yunnan Province. To examine the effects of different pomegranate varieties on the development and reproduction of A. inouei, the biological characteristics, such as the developmental duration, the survival rate and reproduction of this pest feeding on five pomegranate varieties including Tianlvzi, Houpitianshazi, Tianguangyan, Suanlvzi and Suanshazi were observed respectively, and the life table parameters were established under the laboratory conditions of (25±1) ℃, RH (70±10)% and a photoperiod of 15 L:9 D. The results showed that there were no significant differences in the egg stage, larval stage, pupal stage, the longevity of male adults, generation duration form egg to adult and egg hatch rate among the five varieties. There were significant differences in the pre-pupal stage, the longevity of female adults, larval survival, pupation, eclosion and total survival rates, the number of eggs laid per female as well as male and female pupal mass among the five varieties, and all of which except the larval survival were higher on Suanlvzi, followed by Houpitianshazi, but there was no significant difference between these two varieties. The results of life table showed the net reproduction rate, the intrinsic rate of increase and finite rate of increase of the Suanlvzi population were the highest. There were no significant differences in the mean generation time among the five varieties, but significant difference was observed in the population doubling time, which was the shortest on Suanlvzi population. The development and reproduction of A. inouei were better on the Suanlvzi and Houpitianshazi among the five varieties.

Context-Dependent Plastic Response during Egg-Laying in a Widespread Newt Species

PubMed Central

Tóth, Zoltán

2015-01-01

Previous research on predator-induced phenotypic plasticity mostly focused on responses in morphology, developmental time and/or behaviour during early life stages, but the potential significance of anticipatory parental responses has been investigated less often. In this study I examined behavioural and maternal responses of gravid female smooth newts, Lissotriton vulgaris, in the presence of chemical cues originating from invertebrate predators, Acilius sulcatus water beetles and Aeshna cyanea dragonfly larvae. More specifically, I tested the extent of oviposition preference, plasticity in egg-wrapping behaviour and plasticity in egg size when females had the possibility to lay eggs at oviposition sites with and without predator cues during overnight trials. I found that individuals did not avoid laying eggs in the environment with predator cues; however, individuals that deposited eggs into both environments adjusted the size of the laid eggs to the perceived environment. Females deposited larger eggs earlier in the season but egg size decreased with time in the absence of predator cues, whereas individuals laid eggs of average size throughout the investigated reproductive period when such cues were present. Also, egg size was found to be positively related to hatching success. Individuals did not adjust their wrapping behaviour to the presence of predator cues, but females differed in the extent of egg-wrapping between ponds. Females’ body mass and tail depth were also different between ponds, whereas their body size was positively associated with egg size. According to these results, female smooth newts have the potential to exhibit activational plasticity and invest differently into eggs depending on temporal and environmental factors. Such an anticipatory response may contribute to the success of this caudate species under a wide range of predator regimes at its natural breeding habitats. PMID:26291328

Comparative toxicity of two Iodophors to rainbow trout eggs

USGS Publications Warehouse

Amend, Donald F.

1974-01-01

Toxicity of Wescodyne(R) and Betadine(R) to eyed eggs was not adversely affected by water hardness (as calcium and magnesium) or by exposure periods up to 60 min. Both iodophors were much more toxic below pH 6.0 than at pH 8.0. In general Wescodyne was slightly more toxic than Betadine. Significant egg loss occurred if freshly fertilized eggs were water-hardened in either iodophor at 100 ppm of iodine, but egg loss at 25 ppm of iodine or at 100 ppm if the eggs were disinfected 30 min after water hardening was comparable to the control. Also, there was no effect on the egg mortality or fry development following single or multiple exposures after eggs were water hardened. At pH 6.0 and above, Wescodyne and Betadine at 100 ppm iodine in a 15-min dip would be safe to use on rainbow trout eggs at any stage of development after water hardening. Recommendations and precautions for hatchery use are given.

Neurotoxic and teratogenic effects of an organophosphorus insecticide (phenyl phosphonothioic acid-O-ethyl -O-[4-nitrophenyl] ester) on mallard development

USGS Publications Warehouse

Hoffman, D.J.; Sileo, L.

1984-01-01

Phenyl phosphonothioic acid-O-ethyl-O-[4-nitrophenyl] ester (EPN) is one of the 10 most frequently used organophosphorus insecticides and causes delayed neurotoxicity in adult chickens and mallards. Small amounts of organophosphorus insecticides placed on birds' eggs are embryotoxic and teratogenic. For this reason, the effects of topical egg application on EPN were examined on mallard (Anas platyrhynchos) embryo development. Mallard eggs were treated topically at 72 hr of incubation with 25 microliter of a nontoxic oil vehicle or with EPN in the vehicle at concentrations of approximately 12, 36, or 108 micrograms/g egg, equivalent to one, three, and nine times the agricultural level of application used to spray crops. Treatment with EPN resulted in 22 to 44% mortality over this dose range by 18 days of development compared with 4 and 5% for untreated and vehicle-treated controls. EPN impaired embryonic growth and was highly teratogenic: 37-42% of the surviving embryos at 18 days were abnormal with cervical and axial scoliosis as well as severe edema. Brain weights were significantly lower in EPN-treated groups at different stages of development including hatchlings. Brain neurotoxic esterase (NTE) activity was inhibited by as much as 91% at 11 days, 81% at 18 days, and 79% in hatchlings. Examination of brain NTE activity during the course of normal development revealed an increase of nearly sixfold from Day 11 through hatching. The most rapid increase occurred between Day 20 and hatching. Brain acetylcholinesterase (AChE) activity was inhibited by as much as 41% at 11 days, 47% at 18 days, and 20% in hatchlings. Plasma cholinesterase and alkaline phosphatase activities were inhibited and plasma aspartate aminotransferase activity was increased at one or more stages of development. Hatchlings from EPN-treated eggs were weaker and slower to right themselves. Histopathological examination did not reveal demyelination and axonopathy of the spinal cord that was characteristic of delayed neurotoxicity in adult birds.

'Banking time': egg freezing and the negotiation of future fertility.

PubMed

Waldby, Catherine

2015-01-01

This paper examines the relatively recent practice of non-medical egg freezing, in which women bank their eggs for later use in conceiving a child. Non-medical egg freezing has only been available for about the last five years, as new vitrification techniques have made the success rates for actual conception more reliable than the earlier method of slow freezing. I draw on interviews with both clinicians and women who have banked their eggs to consider how this novel practice articulates with broader issues about the relationship between sexuality, reproduction and the political economy of household formation. Non-medical egg-freezing provides a technical solution to a number of different problems women face with regard to the elongation of the life course, the extension of education, the cost of household establishment and the iterative nature of relationship formation, thematised by the ubiquity of internet dating among the interviewees. I focus on the ways women used egg freezing to manage and reconcile different forms of time.

A Schistosoma haematobium-specific real-time PCR for diagnosis of urogenital schistosomiasis in serum samples of international travelers and migrants.

PubMed

Cnops, Lieselotte; Soentjens, Patrick; Clerinx, Jan; Van Esbroeck, Marjan

2013-01-01

Diagnosis of urogenital schistosomiasis by microscopy and serological tests may be elusive in travelers due to low egg load and the absence of seroconversion upon arrival. There is need for a more sensitive diagnostic test. Therefore, we developed a real-time PCR targeting the Schistosoma haematobium-specific Dra1 sequence. The PCR was evaluated on urine (n = 111), stool (n = 84) and serum samples (n = 135), and one biopsy from travelers and migrants with confirmed or suspected schistosomiasis. PCR revealed a positive result in 7/7 urine samples, 11/11 stool samples and 1/1 biopsy containing S. haematobium eggs as demonstrated by microscopy and in 22/23 serum samples from patients with a parasitological confirmed S. haematobium infection. S. haematobium DNA was additionally detected by PCR in 7 urine, 3 stool and 5 serum samples of patients suspected of having schistosomiasis without egg excretion in urine and feces. None of these suspected patients demonstrated other parasitic infections except one with Blastocystis hominis and Entamoeba cyst in a fecal sample. The PCR was negative in all stool samples containing S. mansoni eggs (n = 21) and in all serum samples of patients with a microscopically confirmed S. mansoni (n = 22), Ascaris lumbricoides (n = 1), Ancylostomidae (n = 1), Strongyloides stercoralis (n = 1) or Trichuris trichuria infection (n = 1). The PCR demonstrated a high specificity, reproducibility and analytical sensitivity (0.5 eggs per gram of feces). The real-time PCR targeting the Dra1 sequence for S. haematobium-specific detection in urine, feces, and particularly serum, is a promising tool to confirm the diagnosis, also during the acute phase of urogenital schistosomiasis.

Motion compensated image processing and optimal parameters for egg crack detection using modified pressure

USDA-ARS?s Scientific Manuscript database

Shell eggs with microcracks are often undetected during egg grading processes. In the past, a modified pressure imaging system was developed to detect eggs with microcracks without adversely affecting the quality of normal intact eggs. The basic idea of the modified pressure imaging system was to ap...

Improved modified pressure imaging and software for egg micro-crack detection and egg quality grading

USDA-ARS?s Scientific Manuscript database

Cracks in the egg shell increase a food safety risk. Especially, eggs with very fine, hairline cracks (micro-cracks) are often undetected during the grading process because they are almost impossible to detect visually. A modified pressure imaging system was developed to detect eggs with micro-crack...

New technique for fertilizing eggs of burbot, asp and ide under hatchery conditions.

PubMed

Kucharczyk, Dariusz; Nowosad, Joanna; Łuczyński, Marek J; Targońska, Katarzyna

2016-09-01

The development of a new protocol for egg fertilization may increase embryo survival and benefit the aquaculture process. In the present study, a new technique of partially adding sperm to activated eggs in the artificial fertilization of burbot (Lota lota), ide (Leuciscus idus) and asp (Aspius aspius) eggs was evaluated. If the same volume of sperm was divided into two or three parts and added to eggs in 30-60s intervals, it significantly improved embryo survival at the eyed-egg-stage of development. In the present study, the periodic addition of spermatozoa to eggs affected fertilization (ide and asp) and embryo survival rates (ide, asp and burbot) and might be successfully applied under hatchery conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of pre-incubation of eggs in fresh water and varying sperm concentration on fertilization rate in sterlet sturgeon, Acipenser ruthenus.

PubMed

Siddique, Mohammad Abdul Momin; Butts, Ian Anthony Ernest; Psenicka, Martin; Linhart, Otomar

2015-08-01

Standardization of fertilization protocols for sterlet Acipenser ruthenus is crucial for improving reproductive techniques and for conservation purposes. Our objectives were to determine the number of sperm (tested 430,000:1, 43,000:1, 4300:1, 430:1 sperm to egg) required to fertilize eggs and explore how pre-incubation of eggs in freshwater for 0min, 0.5min, 1min, and 10min interacts with different sperm ratios. Fertilization success ranged from 29.7% at 430:1 to 84.2% at 430,000:1. Pre-incubation time had no effect on fertilization success at 430,000:1 and 43,000:1 sperm to egg ratios, while it was significant at the 4300:1 and 430:1 ratios. The use of adequate experimental suboptimal sperm to egg ratio revealed a positive effect of pre-incubation time, such that at the 430:1 ratio, 0.5min pre-incubation increased the fertilization rate than 10min. At 0min pre-incubation the proportion of fertilized eggs increased at the 430,000:1 ratio, while at 1min fertilization increased at the 4300:1 ratio. At the 10min pre-incubation time, fertilization increased at the 43,000:1 ratio. Moreover, at the 0.5min pre-incubation time, the 43,000:1 ratio increased the fertilization rate than the 430:1 ratio. Generally, for 430:1 ratio, the fertilization rate is lower than in control. Transmission electron microscopy showed that pre-incubation of eggs in water for <10min does not trigger a cortical reaction or the formation of a perivitelline space. Results suggest that with a low sperm to egg ratio 0.5 to 1min pre-incubation of eggs in freshwater prior to fertilization can enhance fertilization rate of sterlet. Copyright © 2015 Elsevier B.V. All rights reserved.

Modified egg as a nutritional supplement during peak brain development: a new target for fortification.

PubMed

Shapira, Niva

2009-01-01

Though eggs have the unique capacity, like breastmilk, to concentrate essential nutrients required for early growth and brain development of offspring - i.e. n-3 PUFA, increasingly deficient and sources contaminated - cholesterol and allergy concerns often exclude them from perinatal recommendations. Egg's potential contribution of key nutrients required for peak brain development are re-evaluated vis-à-vis fortification, accessibility, and risks. Contributions of standard (USDA) and fortified (selected market-available) egg compositions to perinatal requirements for critical brain-supporting nutrients were compared to human and cow milks, and risks and recommendations evaluated. Standard egg has already higher concentrations/kcal of iron, selenium, zinc, choline, vitamins B12 and E, and essential amino acids (plus taurine) than human milk. Fortified egg could further yield significant n-3 PUFA % recommendations for pregnancy-lactation (total n-3 69.6-75.0% [DRI=1400-1300 mg/day]), including DHA (120.1-129.3%, mostly approximately 80% [calculated DRI=140-130 mg/day]), plus antioxidant vitamins A (9.0-15.2%) and E (51.6-65.3%), and minerals iodine (33.6-44.5%) and selenium (33.7-39.3%); % recommendations for children (1-3 y) even more. Cholesterol, important for nerve membranes and learning, may not be generally contraindicated in childbearing-aged women (approximately 10.5% hypercholesterolemia), and early-life egg exposure may increase tolerance. Egg-inclusive perinatal nutrition programs have shown significant contributions. Eggs, especially target-fortified, may provide a unique nutritional supplement for peak brain development continously during pregnancy, nursing, and infancy (from 6 months), especially vs. insufficiencies. Missing nutritional opportunities by egg exclusion vs. concerns of hypercholesterolemia or allergy could be addressed individually, rather than as general recommendations, warranting further research and targeted egg design.

Development and survival of Anopheles gambiae eggs in drying soil: influence of the rate of drying, egg age, and soil type.

PubMed

Shililu, J I; Grueber, W B; Mbogo, C M; Githure, J I; Riddiford, L M; Beier, J C

2004-09-01

Little is known about the contribution made by the egg stage of African malaria vectors to the rapid rise in adult populations following the onset of seasonal rains. To examine this issue, we evaluated the viability of Anopheles gambiae eggs in drying soil in the laboratory. Survival data were collected from field-caught mosquitoes kept in sandy loam soil and laboratory-reared colonies kept in sandy loam soil and black cotton soil. Under high, medium, and low soil-moisture regimes, egg viability declined sharply with increased duration of drying. Eggs remained viable in drying sandy loam soil for 1, 5, and 10 days, but not after 15 or 20 days. The most dramatic decline in hatching success occurred between drying days 1 (78-83% hatch) and 5 (20-23% hatch). In contrast, eggs reared in high-moisture black cotton soil remained viable for up to 15 days. Furthermore, after 5 drying days, high-, medium-, and low-moisture soils averaged 59, 47, and 31% hatching success, respectively. We recovered unhatched eggs from sandy loam soils to examine the developmental status of the embryos. A majority of the unhatched eggs that were recovered from days 15 and 20 in sandy loam soils contained fully developed late-stage embryos. Thus, unhatched eggs completed embryonic development but probably died before receiving an appropriate hatching stimulus. Our results suggest that the absolute moisture content of the soil does not alone determine hatching success of anopheline eggs. Rather, soil moisture, together with the rate of drying, physiological factors associated with the age of the egg, and the type of soil in which the egg rests likely influence survival.

Migratory life histories explain the extreme egg-size dimorphism of Eudyptes penguins.

PubMed

Crossin, Glenn T; Williams, Tony D

2016-10-12

When successive stages in the life history of an animal directly overlap, physiological conflicts can arise resulting in carryover effects from one stage to another. The extreme egg-size dimorphism (ESD) of Eudyptes penguins, where the first-laid A-egg is approximately 18-57% smaller than the second-laid B-egg, has interested researchers for decades. Recent studies have linked variation in this trait to a carryover effect of migration that limits the physiology of yolk production and egg sizes. We assembled data on ESD and estimates of migration-reproduction overlap in penguin species and use phylogenetic methods to test the idea that migration-reproduction overlap explains variation in ESD. We show that migration overlap is generally restricted to Eudyptes relative to non-Eudyptes penguins, and that this overlap (defined as the amount of time that egg production occurs on land versus at sea during homeward migration) is significantly and positively correlated with the degree of ESD in Eudyptes In the non-Eudyptes species, however, ESD was unrelated to migration overlap as these species mostly produce their clutches on land. Our results support the recent hypothesis that extreme ESD of Eudyptes penguins evolved, in part, as a response to selection for a pelagic overwinter migration behaviour. This resulted in a temporal overlap with, and thus a constraint on, the physiology of follicle development, leading to smaller A-egg size and greater ESD. © 2016 The Author(s).

Membrane junctions in Xenopus eggs: their distribution suggests a role in calcium regulation.

PubMed

Gardiner, D M; Grey, R D

1983-04-01

We have observed the presence of membrane junctions formed between the plasma membrane and cortical endoplasmic reticulum of mature, unactivated eggs of xenopus laevis. The parallel, paired membranes of the junction are separated by a 10-mn gap within which electron-dense material is present. This material occurs in patches with an average center-to-center distance of approximately 30 nm. These junctions are rare in immature (but fully grown) oocytes (approximately 2 percent of the plasma membrane is associated with junctions) and increase dramatically during progesterone-induced maturation. Junctions in the mature, unactivated egg are two to three times more abundant in the animal hemisphere (25-30 percent of the plasma membrane associated with junction) as compared with the vegetal hemisphere (10-15 percent). Junction density decreases rapidly to values characteristic of immature oocytes in response to egg activation. The plasma membrane-ER junctions of xenopus eggs are strikingly similar in structure to membrane junctions in muscle cells thought to be essential in the triggering of intracellular calcium release from the sarcoplasmic reticulum. In addition, the junctions' distinctive, animal-vegetal polarity of distribution, their dramatic appearance during maturation, and their disapperance during activation are correlated with previously documented patterns of calcium-mediated events in anuran eggs. We discuss several lines of evidence supporting the hypothesis that these junctions in xenopus eggs are sites that transduce extracellular events into intracellular calcium release during fertilization and activation of development.

Brine shrimp development in space: ground-based data to shuttle flight results

NASA Technical Reports Server (NTRS)

Spooner, B. S.; DeBell, L.; Hawkins, L.; Metcalf, J.; Guikema, J. A.; Rosowski, J.

1992-01-01

The brine shrimp, Artemia salina, has been used as a model system to assess microgravity effects on developing organisms. Following fertilization and early development, the egg can arrest in early gastrula as a dehydrated cyst stage that is stable to harsh environments over long time periods. When salt water is added, the cysts can reactivate, with embryonic development and egg hatching occurring in about 24 h. A series of larval molts or instars, over about a 2 week period, results in the adult crustacean. We have assessed these developmental events in a closed syringe system, a bioprocessing module, in ground-based studies, and have conducted preliminary in-orbit experiments aboard the Space Shuttle Atlantis during the flights of STS-37 and STS-43. Although the in-flight data are limited, spectacular degrees of development have been achieved.

Multi-Component T2 Relaxation Studies of the Avian Egg

PubMed Central

Mitsouras, Dimitris; Mulkern, Robert V.; Maier, Stephan E.

2015-01-01

Purpose To investigate the tissue-like multiexponential T2 signal decays in avian eggs. Methods Transverse relaxation studies of raw, soft-boiled and hard-boiled eggs were performed at 3 Tesla using a 3D Carr-Purcell-Meiboom-Gill (CPMG) imaging sequence. Signal decays over a TE range of 11 to 354 ms were fitted assuming single- and multi-component signal decays with up to three separately decaying components. Fat saturation was used to facilitate spectral assignment of observed decay components. Results Egg white, yolk and the centrally located latebra all demonstrate nonmonoexponential T2 decays. Specifically, egg white exhibits two-component decays with intermediate and long T2 times. Meanwhile, yolk and latebra are generally best characterized with triexponential decays, with short, intermediate and very long T2 decay times. Fat saturation revealed that the intermediate component of yolk could be attributed to lipids. Cooking of the egg profoundly altered the decay curves. Conclusion Avian egg T2 decay curves cover a wide range of decay times. Observed T2 components in yolk and latebra as short as 10 ms, may prove valuable for testing clinical sequences designed to measure short T2 components, such as myelin-associated water in the brain. Thus we propose that the egg can be a versatile and widely available MR transverse relaxation phantom. PMID:26037128

Biomechanical evidence suggests extensive eggshell thinning during incubation in the Sanagasta titanosaur dinosaurs

PubMed Central

Taborda, Jeremías R. A.; Fiorelli, Lucas E.; Grellet-Tinner, Gerald

2018-01-01

The reproduction of titanosaur dinosaurs is still a complex and debated topic. Their Late Cretaceous nesting sites are distributed worldwide and their eggs display substantial morphological variations according to the parent species. In contrast to the typical 1.3–2.0 mm thick shells common to eggs of most titanosaur species (e.g., those that nested in Auca Mahuevo, Tama, Toteşti or Boseong), the Cretaceous Sanagasta eggs of Argentina display an unusual shell thickness of up to 7.9 mm. Their oviposition was synchronous with a palaeogeothermal process, leading to the hypothesis that their extra thick eggshell was an adaptation to this particular nesting environment. Although this hypothesis has already been supported indirectly through several investigations, the mechanical implications of developing such thick shells and how this might have affected the success of hatching remains untested. Finite element analyses estimate that the breaking point of the thick-shelled Sanagasta eggs is 14–45 times higher than for other smaller and equally sized titanosaur eggs. The considerable energetic disadvantage for piping through these thick eggshells suggests that their dissolution during incubation would have been paramount for a successful hatching.

Detection of laryngeal function using speech and electroglottographic data.

PubMed

Childers, D G; Bae, K S

1992-01-01

The purpose of this research was to develop quantitative measures for the assessment of laryngeal function using speech and electroglottographic (EGG) data. We developed two procedures for the detection of laryngeal pathology: 1) a spectral distortion measure using pitch synchronous and asynchronous methods with linear predictive coding (LPC) vectors and vector quantization (VQ) and 2) analysis of the EGG signal using time interval and amplitude difference measures. The VQ procedure was conjectured to offer the possibility of circumventing the need to estimate the glottal volume velocity wave-form by inverse filtering techniques. The EGG procedure was to evaluate data that was "nearly" a direct measure of vocal fold vibratory motion and thus was conjectured to offer the potential for providing an excellent assessment of laryngeal function. A threshold based procedure gave 75.9 and 69.0% probability of pathological detection using procedures 1) and 2), respectively, for 29 patients with pathological voices and 52 normal subjects. The false alarm probability was 9.6% for the normal subjects.

["The first stages of the human egg" by Auguste d'Eternod published one hundred years ago in the Comptes Rendus de l'Association des Anatomistes].

PubMed

Catala, M

2014-06-01

The development of the embryo and foetus fascinates, but its study in humans is difficult because of both technical and ethical problems. Auguste d'Eternod, Swiss embryologist, published in 1913 an article entitled "The early stages of the human egg" in the Comptes Rendus de l'Association des Anatomistes, the ancestor of the journal Morphologie. This work is focused not only on the early stages of development: fertilization, cleavage of the egg, blastocyst formation, gastrulation, but also on the extra-embryonic processes characteristic of mammals. On the occasion of the centenary of the publication of this work, I propose a critical review by placing the data published in the literature and historical context of the time. Finally, I try to extract from these observations the concepts that are still used today by embryologists. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Timing of the calcium intake and effect of calcium deficiency on behaviour and egg laying in captive great tits, Parus major.

PubMed

Graveland, J; Berends, A E

1997-01-01

The calcium demand of egg-laying birds is much higher than in other vertebrates during reproduction. We showed elsewhere that a low level of calcium availability can greatly affect the eggshell quality and reproduction of free-living passerines. However, there are few data on calcium demand and calcium intake in relation to egg laying and behaviour and egg-laying performance under conditions of calcium shortage in nondomesticated birds. We examined these aspects in an experiment with captive great tits, Parus major, on a diet deficient in calcium, with or without snail shells as an additional calcium source. More than 90% of the calcium intake for egg production took place during the egg-laying period. Females ingested about 1.7 times as much calcium as they deposited in eggshells. Removing the snail shells after the first egg resulted in eggshell defects and interruptions of laying after 1-3 d. Females without snail shells doubled their searching effort and started to burrow in the soil and to eat sand, small stones, and their own eggs. Most calcium was consumed in the evening, probably to supplement the calcium available from the medullary bone with an additional calcium source in the gut during eggshell formation. The results demonstrated that eggshell formation requires accurate timing of the calcium intake and that obtaining sufficient calcium is time-consuming, even in calcium-rich environments. These factors pertaining to calcium intake greatly affect the ability of birds to collect sufficient calcium for eggshell formation in calcium-poor areas.

Comparative ovicidal activity of Moringa oleifera leaf extracts on Fasciola gigantica eggs

PubMed Central

Hegazi, Ahmed G.; Megeed, Kadria N. Abdel; Hassan, Soad E.; Abdelaziz, M. M.; Toaleb, Nagwa I.; Shanawany, Eman E. El; Aboelsoued, Dina

2018-01-01

Background: Fasciolosis is an important zoonotic disease affecting the productive performance of farm animals in Egypt. Aim: The aim of the present study was comparing the ovicidal effect of different extracts as an alcoholic (Methanolic and Ethanolic) and aqueous Moringa oleifera leaf extracts on Fasciola gigantica non-embryonated and developed eggs. Materials and Methods: Tested concentrations of extracts ranged from 12.5 to 800 mg/ml. Nitroxynil was used as reference drug with a dose of 100 mg/ml. Results: M. oleifera alcoholic and aqueous extracts showed a concentration-dependent ovicidal effect on F. gigantica non-embryonated and developed eggs. Based on LC50 values, water extract showed the highest ovicidal activity since it registered the lowest values of 2.6 mg/ml on non-embryonated eggs. Non-embryonated eggs were more susceptible to aqueous extract than developed eggs. On the other hand, the developed eggs were more susceptible to ethanolic extract than non-embryonated eggs even the lowest LC50 (12.38 mg/ml). Conclusion: M. oleifera leaf extracts especially aqueous extract could be a promising step in the field of controlling fascioliasis. Further, in vivo studies are needed to enlighten the therapeutic potential of M. oleifera extracts in treating F. gigantica infection. PMID:29657406

Ovicidal activity of Metarhizium brunneum (Mb F52) on dengue fever vector, Aedes aegypti

USDA-ARS?s Scientific Manuscript database

The ovicidal activity of Metarhizium brunneum F52 (Mb F52) grown from granules was evaluated against Aedes aegypti eggs over time. Survival of larvae from treated eggs was significantly less when compared with untreated eggs at 7, 10 and 14 days post treatment. Only 27 % of treated eggs produced vi...

How dietary plant nectar affects the survival, growth, and fecundity of a cursorial spider Cheiracanthium inclusum (Araneae: Miturgidae).

PubMed

Taylor, R M; Pfannenstiel, R S

2009-10-01

We measured the effects of plant nectar consumption on Cheiracanthium inclusum (Hentz) (Miturgidae), an agriculturally important spider. Newly emerged spiderlings were reared on the eggs of Helicoverpa zea (Boddie) at four prey densities, 1, 5, 25, or 125 eggs, three times a week, with or without nectar. Nectar came from the extrafloral nectaries of Indian almond, Terminalia cattapa L. (Combretaceae). The addition of nectar to prey (1) allowed spiderlings on the 1-egg diet to survive longer and molt many more times; (2) allowed virtually all of the spiderlings on the 5-egg diet to become small adults and 50% to mate and reproduce versus those without nectar, none of which matured to adulthood; and (3) increased fecundity of females on 5-egg and 25-egg diets to the level of females fed five times the amount of prey. These results show that spiders that feed on nectar increase their fitness with increased survival, growth, and fecundity, particularly when density of prey is inadequate or marginal.

Detection and enumeration of Salmonella enteritidis in homemade ice cream associated with an outbreak: comparison of conventional and real-time PCR methods.

PubMed

Seo, K H; Valentin-Bon, I E; Brackett, R E

2006-03-01

Salmonellosis caused by Salmonella Enteritidis (SE) is a significant cause of foodborne illnesses in the United States. Consumption of undercooked eggs and egg-containing products has been the primary risk factor for the disease. The importance of the bacterial enumeration technique has been enormously stressed because of the quantitative risk analysis of SE in shell eggs. Traditional enumeration methods mainly depend on slow and tedious most-probable-number (MPN) methods. Therefore, specific, sensitive, and rapid methods for SE quantitation are needed to collect sufficient data for risk assessment and food safety policy development. We previously developed a real-time quantitative PCR assay for the direct detection and enumeration of SE and, in this study, applied it to naturally contaminated ice cream samples with and without enrichment. The detection limit of the real-time PCR assay was determined with artificially inoculated ice cream. When applied to the direct detection and quantification of SE in ice cream, the real-time PCR assay was as sensitive as the conventional plate count method in frequency of detection. However, populations of SE derived from real-time quantitative PCR were approximately 1 log higher than provided by MPN and CFU values obtained by conventional culture methods. The detection and enumeration of SE in naturally contaminated ice cream can be completed in 3 h by this real-time PCR method, whereas the cultural enrichment method requires 5 to 7 days. A commercial immunoassay for the specific detection of SE was also included in the study. The real-time PCR assay proved to be a valuable tool that may be useful to the food industry in monitoring its processes to improve product quality and safety.

Toxicity of TNT Wastewaters to Aquatic Organisms. Volume 3. Chronic Toxicity of LAP Wastewater and 2,4,6-Trinitrotoluene.

DTIC Science & Technology

1985-05-01

problems with fungal infe c- tion, we flushed the eggs daily with malachite green up to the time of 17 5. hatching (Leitritz and Levis, 1976). After...spread of disease to other eggs. Despite prophylactic treatment with malachite green up to the time of hatching, many of the eggs were lost to fungal

Effects of gamma irradiation on the grape vine moth, Lobesia botrana, eggs

NASA Astrophysics Data System (ADS)

Mansour, M.; Al-Attar, J.

2012-11-01

Eggs of the grape vine moth, Lobesia botrana (Denis and Schiffermuller), ranging in age from 1-24 to 73-96 h, were exposed, at 24 h intervals, to gamma radiation ranging from 25-600 Gy. The effects of gamma radiation on egg hatch, pupation, adult emergence, sex ratio and rate of development were examined. Results showed that the radiosensitivity of the grape vine moth eggs decreased with increasing age and increased with increasing radiation dose. Egg hatch in 1-24 h old eggs was significantly affected at 25 Gy and completely prevented at 100 Gy. At the age of 25-48 h, radiation sensitivity was only a little lower; egg hatch at 100 Gy was <1% and at 125 Gy no egg hatch was observed. Egg sensitivity to gamma irradiation decreased significantly in the 49-72 h age group; egg hatch was 66% at 100 Gy, and 500 Gy did not completely stop egg hatch (<1%). Eggs irradiated a few hours before egg hatch (73-96 h old) were the most resistant; 150 Gy had no significant effect on egg hatch and at 600 Gy over 33% of the eggs hatched. When pupation or adult emergence was used as a criterion for measuring effectiveness, however, the effects of gamma radiation were very severe. In the most resistant age group (73-96 h old), 150 Gy completely prevented pupation and adult emergence and all larvae resulting from eggs irradiated <49 h old died before pupation. In addition, the rate of development of immature stages resulting from irradiated eggs was negatively affected and sex ratio was skewed in favor of males.

Impact of Breakfasts (with or without Eggs) on Body Weight Regulation and Blood Lipids in University Students over a 14-Week Semester

PubMed Central

Rueda, Janice M.; Khosla, Pramod

2013-01-01

The effects of breakfast type on body weight and blood lipids were evaluated in university freshman. Seventy-three subjects were instructed to consume a breakfast with eggs (Egg Breakfast, EB, n = 39) or without (Non-Egg Breakfast, NEB, n = 34), five times/week for 14 weeks. Breakfast composition, anthropometric measurements and blood lipids were measured at multiple times. During the study, mean weight change was 1.6 ± 5.3 lbs (0.73 ± 2.41 kg), but there was no difference between groups. Both groups consumed similar calories for breakfast at all time-points. The EB group consumed significantly more calories at breakfast from protein, total fat and saturated fat, but significantly fewer calories from carbohydrate at every time-point. Cholesterol consumption at breakfast in the EB group was significantly higher than the NEB group at all time points. Breakfast food choices (other than eggs) were similar between groups. Blood lipids were similar between groups at all time points, indicating that the additional 400 mg/day of dietary cholesterol did not negatively impact blood lipids. PMID:24352089

Detection of quinolones in commercial eggs obtained from farms in the Espaíllat Province in the Dominican Republic.

PubMed

Moscoso, S; de los Santos, F Solís; Andino, A G; Diaz-Sanchez, Sandra; Hanning, I

2015-01-01

Previously, we reported the use of quinolones in broiler chickens resulted in residues in retail poultry meat obtained from nine districts in the Santiago Province of the Dominican Republic. Residues in poultry products are a concern due to consumer allergies and the potential to develop antibiotic-resistant bacteria. Given the use of quinolones in poultry production and our previous findings in poultry meat, the objective of this study was to evaluate the presence of quinolone residues in eggs. Samples were collected from 48 different farms located in three of the four municipalities (Moca, Cayetano Germosén, and Jamao) of the Espaíllat Province. Each farm was sampled three times between July and September for a total of 144 samples. Samples were evaluated qualitatively and quantitatively for quinolone residues using the Equinox test. Operation systems (cage or floor), seasonality, and location were considered along with egg-producer sizes that were defined as small scale, <30,000 eggs per day; medium scale, 30,000 to 60,000 eggs per day; or large scale, >60,000 eggs per day. From small-, medium-, and large-scale producers, 69, 50, and 40% of samples were positive for quinolone residues, respectively. A greater number of samples were positive (61%) in floor-laying hen producers compared with those using cages (40%). In the Jamao municipality, 67% of the samples were positive compared with Moca and Cayetano Germosén, where 56 and 25% of samples were positive, respectively. Sampling time had an effect on percent positives: samples collected in July, August, and September were 71, 19, and 63% positive, respectively. Overall, 51% of the samples obtained from eggs produced in the province of Espaíllat were positive for quinolone residues at levels higher than the maximum limits for edible tissue established by the regulatory agencies, including the European Union and U.S. Department of Agriculture. The results obtained from this research confirmed the presence of quinolone residue in eggs, which may present a health risk to some consumers.

QuantiFly: Robust Trainable Software for Automated Drosophila Egg Counting.

PubMed

Waithe, Dominic; Rennert, Peter; Brostow, Gabriel; Piper, Matthew D W

2015-01-01

We report the development and testing of software called QuantiFly: an automated tool to quantify Drosophila egg laying. Many laboratories count Drosophila eggs as a marker of fitness. The existing method requires laboratory researchers to count eggs manually while looking down a microscope. This technique is both time-consuming and tedious, especially when experiments require daily counts of hundreds of vials. The basis of the QuantiFly software is an algorithm which applies and improves upon an existing advanced pattern recognition and machine-learning routine. The accuracy of the baseline algorithm is additionally increased in this study through correction of bias observed in the algorithm output. The QuantiFly software, which includes the refined algorithm, has been designed to be immediately accessible to scientists through an intuitive and responsive user-friendly graphical interface. The software is also open-source, self-contained, has no dependencies and is easily installed (https://github.com/dwaithe/quantifly). Compared to manual egg counts made from digital images, QuantiFly achieved average accuracies of 94% and 85% for eggs laid on transparent (defined) and opaque (yeast-based) fly media. Thus, the software is capable of detecting experimental differences in most experimental situations. Significantly, the advanced feature recognition capabilities of the software proved to be robust to food surface artefacts like bubbles and crevices. The user experience involves image acquisition, algorithm training by labelling a subset of eggs in images of some of the vials, followed by a batch analysis mode in which new images are automatically assessed for egg numbers. Initial training typically requires approximately 10 minutes, while subsequent image evaluation by the software is performed in just a few seconds. Given the average time per vial for manual counting is approximately 40 seconds, our software introduces a timesaving advantage for experiments starting with as few as 20 vials. We also describe an optional acrylic box to be used as a digital camera mount and to provide controlled lighting during image acquisition which will guarantee the conditions used in this study.

QuantiFly: Robust Trainable Software for Automated Drosophila Egg Counting

PubMed Central

Waithe, Dominic; Rennert, Peter; Brostow, Gabriel; Piper, Matthew D. W.

2015-01-01

We report the development and testing of software called QuantiFly: an automated tool to quantify Drosophila egg laying. Many laboratories count Drosophila eggs as a marker of fitness. The existing method requires laboratory researchers to count eggs manually while looking down a microscope. This technique is both time-consuming and tedious, especially when experiments require daily counts of hundreds of vials. The basis of the QuantiFly software is an algorithm which applies and improves upon an existing advanced pattern recognition and machine-learning routine. The accuracy of the baseline algorithm is additionally increased in this study through correction of bias observed in the algorithm output. The QuantiFly software, which includes the refined algorithm, has been designed to be immediately accessible to scientists through an intuitive and responsive user-friendly graphical interface. The software is also open-source, self-contained, has no dependencies and is easily installed (https://github.com/dwaithe/quantifly). Compared to manual egg counts made from digital images, QuantiFly achieved average accuracies of 94% and 85% for eggs laid on transparent (defined) and opaque (yeast-based) fly media. Thus, the software is capable of detecting experimental differences in most experimental situations. Significantly, the advanced feature recognition capabilities of the software proved to be robust to food surface artefacts like bubbles and crevices. The user experience involves image acquisition, algorithm training by labelling a subset of eggs in images of some of the vials, followed by a batch analysis mode in which new images are automatically assessed for egg numbers. Initial training typically requires approximately 10 minutes, while subsequent image evaluation by the software is performed in just a few seconds. Given the average time per vial for manual counting is approximately 40 seconds, our software introduces a timesaving advantage for experiments starting with as few as 20 vials. We also describe an optional acrylic box to be used as a digital camera mount and to provide controlled lighting during image acquisition which will guarantee the conditions used in this study. PMID:25992957

Parent psychological adjustment, donor conception and disclosure: a follow-up over 10 years

PubMed Central

Blake, L.; Jadva, V.; Golombok, S.

2014-01-01

STUDY QUESTION What is the relationship between parent psychological adjustment, type of gamete donation (donor insemination, egg donation) and parents' disclosure of their use of donated gametes to their children. SUMMARY ANSWER Disclosure of donor origins to the child was not always associated with optimal levels of psychological adjustment, especially for fathers in donor insemination families. WHAT IS KNOWN ALREADY Cross-sectional analyses have found mothers and fathers who conceived a child using donated sperm or eggs to be psychologically well-adjusted, with few differences emerging between parents in gamete donation families and parents in families in which parents conceived naturally. The relationship between mothers' and fathers' psychological well-being, type of gamete donation (donor insemination, egg donation) and parents' disclosure decisions has not yet been examined. STUDY DESIGN, SIZE, DURATION In this follow-up study, data were obtained from mothers and fathers in donor insemination and egg donation families at 5 time points; when the children in the families were aged 1, 2, 3, 7 and 10. In the first phase of the study, 50 donor insemination families and 51 egg donation families with a 1-year-old child participated. By age 10, the study included 34 families with a child conceived by donor insemination and 30 families with a child conceived by egg donation, representing 68 and 58% of the original sample, respectively. PARTICIPANTS/MATERIALS, SETTING, METHODS Families were recruited through nine fertility clinics in the UK. Standardized questionnaires assessing depression, stress and anxiety were administered to mothers and fathers in donor insemination and egg donation families. MAIN RESULTS AND THE ROLE OF CHANCE Mothers and fathers in both donor insemination and egg donation families were found to be psychologically well-adjusted; for the vast majority of parents' levels of depression, anxiety and parenting stress were found to be within the normal range at all 5 time points. Disclosure of the child's donor origins to the child was not always associated with optimal levels of parental psychological adjustment. For example, disclosure was associated with lower levels of psychological well-being for certain groups in particular (such as fathers in donor insemination families), at certain times (when children are in middle childhood and have a more sophisticated understanding of their donor origins). LIMITATIONS, REASONS FOR CAUTION Owing to small sample sizes, the value of this study lies not in its generalizability, but in its potential to point future research in new directions. WIDER IMPLICATIONS OF THE FINDINGS Donor insemination and egg donation families are a heterogeneous group, and future research should endeavour to obtain data from fathers as well as mothers. Support and guidance in terms of disclosure and family functioning might be most beneficial for parents (and especially fathers) in donor insemination families, particularly as the child grows older. The more that is known about the process of disclosure over time, from the perspective of the different members of the family, the better supported parents and their children can be. STUDY FUNDING COMPETING INTEREST(S) The project described was supported by grant number RO1HD051621 from the National Institute of Child Health and Human Development. The content is solely the responsibility of the authors and does not represent the official views of the National Institute of Child Health and Human Development or the National Institutes of Health. The authors have no conflict of interest to declare. PMID:25240010

Effects of maternal dietary egg intake during early lactation on human milk ovalbumin concentration: a randomized controlled trial.

PubMed

Metcalfe, J R; Marsh, J A; D'Vaz, N; Geddes, D T; Lai, C T; Prescott, S L; Palmer, D J

2016-12-01

There is limited understanding of how maternal diet affects breastmilk food allergen concentrations, and whether exposure to allergens through this route influences the development of infant oral tolerance or sensitization. To investigate how maternal dietary egg ingestion during early lactation influences egg protein (ovalbumin) levels detected in human breastmilk. In a randomized controlled trial, women were allocated to a dietary group for the first six weeks of lactation: high-egg diet (> 4 eggs per week), low-egg diet (one-three eggs per week) or an egg-free diet. Breastmilk samples were collected at 2, 4 and 6 weeks of lactation for the measurement of ovalbumin. The permeability of the mammary epithelium was assessed by measuring the breastmilk sodium : potassium ratio. Egg-specific IgE and IgG4 were measured in infant plasma at 6 weeks, and prior to the introduction of egg in solids at 16 weeks. Average maternal egg ingestion was associated with breastmilk ovalbumin concentration. Specifically, for each additional egg ingested per week, there was an average 25% increase in ovalbumin concentration (95% CI: 5-48%, P = 0.01). Breastmilk ovalbumin concentrations were significantly higher in the 'high-egg' group (> 4 eggs per week) compared with the 'egg-free' group (P = 0.04). However, one-third of women had no breastmilk ovalbumin detected. No detectable associations were found between mammary epithelium permeability and breastmilk ovalbumin concentrations. Infant plasma egg-specific IgG4 levels were also positively associated with maternal egg ingestion, with an average 22% (95% CI: 3-45%) increase in infant egg-specific IgG4 levels per additional egg consumed per week (P = 0.02). Increased maternal egg ingestion is associated with increased breastmilk ovalbumin, and markers of immune tolerance in infants. These results highlight the potential for maternal diet to benefit infant oral tolerance development during lactation. © 2016 John Wiley & Sons Ltd.

[A comparison of soil contamination with Toxocara canis and Toxocara cati eggs in rural and urban areas of Wielkopolska district in 2000-2005].

PubMed

Mizgajska-Wiktor, Hanna; Jarosz, Wojciech

2007-01-01

The aim of the studies was to compare the degree of soil contamination with Toxocara canis and T. cati eggs in rural and urban areas depending on time of sampling and type of places examined. Material and methods. Over 2000-2005 a total of 538 soil samples from 3 villages and 368 from Poznań city (Poland) areas were examined for Toxocara spp. eggs. In spring 418 samples in rural areas and 184 samples in urban areas were collected and in autumn 120 and 184 respectively. The samples were examined using flotation technique in saturated sodium nitrate. The discrimination of T. canis and T. cati eggs was based on the size of eggs and transparency of shell layers. Results. The contamination of soil with Toxocara eggs was higher in the urban areas (19.8% positive samples) than in the rural ones (15.6% positive samples) and city or village-backyards were most heavily contaminated. Both, in the villages and in the city, the degree of soil contamination with eggs in spring and autumn was similar (17.6 and 14.8% positive samples respectively). T. cati eggs were much more prevalent in urban areas (97% of all eggs recovered) while T. canis in rural areas (84% of all recovered eggs). The share of T. canis and T. cati eggs in soil contamination did not depend on the time of sampling.

Effects of the chitin synthesis inhibitor buprofezin on survival and development of immatures of Chrysoperla rufilabris (Neuroptera: Chrysopidae).

PubMed

Liu, T X; Chen, T Y

2000-04-01

Effects of buprofezin (Applaud), a chitin synthesis inhibitor, on survival and development of eggs, three instars, and pupae of Chrysoperla rufilabris (Burmeister) were determined in the laboratory. Buprofezin at three tested concentrations (100, 500, and 1,000 mg [AI]/liter) did not affect the viability and development of eggs when the eggs were treated, or third instars and pupae when those stages were treated. Although the degree of effects by buprofezin on larvae varied with instar, buprofezin at the higher concentrations (500 and 1,000 mg [AI]/liter) reduced survival rates 17-47% and prolonged the overall development from first instars to adult emergence by 2 or 3 d when first instars were treated, indicating that the first instar is the most vulnerable stage. When second instars were treated, the survival of C. rufilabris from second instars to pupae was not significantly affected. However, the developmental time from second instar to adult emergence was longer in the treatments with the highest concentration (1,000 mg [AI]/liter) than that with the lowest concentration (100 mg [AI]/liter). The compatibility of buprofezin with natural enemies in integrated pest management programs is discussed.

Penguin chicks benefit from elevated yolk androgen levels under sibling competition.

PubMed

Poisbleau, Maud; Müller, Wendt; Carslake, David; Demongin, Laurent; Groothuis, Ton G G; Van Camp, Jeff; Eens, Marcel

2012-01-01

Crested penguins (genus Eudyptes) have a peculiar hatching pattern, with the first-laid egg (A-egg) hatching after the second-laid egg (B-egg) and chicks from A-eggs typically having a much lower survival probability. Maternal yolk androgens have been suggested to contribute to the competitive superiority of the B-chick in southern rockhopper penguins Eudyptes chrysocome, given their important role in mediating sibling competition in other species. We therefore increased the yolk androgen levels in freshly-laid eggs and examined the consequences for sibling competition--via effects on embryonic developmental times, chick growth and early survival. We placed one androgen-treated egg and one control egg into each foster nest, matching them for mass, laying date and laying order. The androgen treatment did not significantly affect embryonic developmental times or chick measurements at hatching. However, elevated yolk androgen levels benefitted chick growth in interaction with the number of siblings in a brood. Chicks from androgen-treated eggs had faster growth in the presence of a sibling than chicks from control eggs. Under these circumstances they also had a higher survival probability. Thus maternal androgens appear to reinforce the observed hatching pattern, facilitating brood reduction. This contrasts to most previous studies in other species where yolk androgens have been shown to compensate for the negative consequences of delayed hatching within the brood hierarchy.

Consequences of elevating plasma testosterone in females of a socially monogamous songbird: evidence of constraints on male evolution?

PubMed

Clotfelter, Ethan D; O'Neal, Dawn M; Gaudioso, Jacqueline M; Casto, Joseph M; Parker-Renga, Ian M; Snajdr, Eric A; Duffy, Deborah L; Nolan, Val; Ketterson, Ellen D

2004-08-01

To explore whether selection for testosterone-mediated traits in males might be constrained by costs of higher testosterone to females, we examined the effects of experimental elevation of plasma testosterone on physiological, reproductive, and behavioral parameters in a female songbird, the dark-eyed junco (Junco hyemalis). We used subcutaneous implants to elevate testosterone (T) in captive and free-living female juncos. In captive birds, we measured the effects of high T on body mass, feather molt, and brood patch formation. In the field, we monitored its effects on the timing of egg laying, clutch size, egg size, egg steroid levels, incubation, and nest-defense behavior. Females implanted with testosterone (T-females) had significantly higher circulating levels of testosterone than did control females (C-females). Captive T-females had lower body mass, were less likely to develop brood patches, and delayed feather molt relative to C-females. Among free-living females, the interval between nest completion and appearance of the first egg was longer for T-females than for C-females and egg yolk concentrations of testosterone were higher, but there were no significant differences in estradiol levels, clutch size, or egg size. Incubation and nest defense behavior were also similar between T- and C-females. Our results suggest that selection on males for higher testosterone might initially lead to a correlated response in females producing changes in body mass and feather molt, both of which could be detrimental. Other possible female responses would be delayed onset of reproduction, which might reduce reproductive success, and higher yolk testosterone, which might have either positive or negative effects on offspring development. We found no reason to expect reduced parental behavior by females as a negative fitness consequence of selection for higher testosterone in males.

Identification of proteins in renaissance paintings by proteomics.

PubMed

Tokarski, Caroline; Martin, Elisabeth; Rolando, Christian; Cren-Olivé, Cécile

2006-03-01

The presented work proposes a new methodology based on proteomics techniques to identify proteins in old art paintings. The main challenging tasks of this work were (i) to find appropriate conditions for extracting proteins from the binding media without protein hydrolysis in amino acids and (ii) to develop analytical methods adapted to the small sample quantity available. Starting from microsamples of painting models (ovalbumin-based, which is the major egg white protein, and egg-based paintings), multiple extraction solutions (HCl, HCOOH, NH3, NaOH) and conditions (ultrasonic bath, mortar and pestle, grinding resin) were evaluated. The best results were obtained using a commercial kit including a synthetic resin, mortar and pestle to grind the sample in an aqueous solution acidified with trifluoroacetic acid at 1% with additional multiple steps of ultrasonic baths. The resulting supernatant was analyzed by MALDI-TOF in linear mode to verify the efficiency of the extraction solution. An enzymatic hydrolysis step was also performed for protein identification; the peptide mixture was analyzed by nanoLC/nanoESI/Q-q-TOF MS/MS with an adapted chromatographic run for the low sample quantity. Finally, the developed methodology was successfully applied to Renaissance art painting microsamples of approximately 10 microg from Benedetto Bonfigli's triptych, The Virgin and Child, St. John the Baptist, St. Sebastian (XVth century), and Niccolo di Pietro Gerini's painting, The Virgin and Child (XIVth century), identifying, for the first time and without ambiguity, the presence of whole egg proteins (egg yolk and egg white) in a painting binder.

Early development of zooxanthella-containing eggs of the corals Porites cylindrica and Montipora digitata: The endodermal localization of zooxanthellae.

PubMed

Hirose, Mamiko; Hidaka, Michio

2006-10-01

We studied the early development of zooxanthellae-containing eggs of the scleractinian corals Porites cylindrica and Montipora digitata to elucidate how zooxanthellae become localized to the endoderm of planulae during the course of development. In both species, zooxanthellae were distributed evenly in the oocytes and delivered almost equally to the blastomeres during cleavage. In P. cylindrica, gastrulation occurred via delamination or ingression, and blastomeres containing zooxanthellae dropped into the blastocoel during gastrulation. Thus, zooxanthellae were restricted to the endodermal cells at the gastrula or early planula stage in P. cylindrica. In M. digitata, gastrulation occurred by a combination of invagination and epiboly to form a somewhat concave gastrula. Zooxanthellae were present in both endodermal and ectodermal cells of early planulae, but they disappeared from the ectoderm as the planulae matured. In our previous study on two species of Pocillopora, we found that zooxanthellae were localized in eggs as well as in embryos, and that blastomeres containing zooxanthellae later dropped into the blastocoel to become restricted to the endoderm (Hirose et al., 2000). The timing and mechanism of zooxanthella localization and types of gastrulation differed among species belonging to the three genera. These results suggest that zooxanthella localization in the embryos reflects the timing of the determination of presumptive endoderm cells and/or specificity of zooxanthellae toward presumptive endoderm cells.

Time Trends and Patterns of Reported Egg Consumption in the U.S. by Sociodemographic Characteristics

PubMed Central

Conrad, Zach; Johnson, LuAnn K.; Roemmich, James N.; Juan, WenYen; Jahns, Lisa

2017-01-01

Eggs have the potential to contribute essential nutrients to nutritionally vulnerable populations on limited food budgets. Further research is needed to better understand patterns of egg consumption across diverse sociodemographic groups in order to inform clinical practice to improve nutrient adequacy. Data on demographics and egg intake of 29,694 U.S. adults were obtained from the National Health and Nutrition Examination Survey, 2001–2012. The National Cancer Institute’s usual intake methodology was used to estimate the distribution of egg intake. Linear and logistic regression models were used to test for time trends in egg consumption and for differences between sociodemographic groups. The proportion of the U.S. population, overall (21%–22%; p = 0.311) and by sociodemographic group (p > 0.05 for all groups), that reported consuming eggs remained unchanged from 2001 to 2012. Mean egg consumption increased overall from 23.0 (95% CI, 20.8–25.2) g/day in 2001–2002 to 25.5 (22.7–28.4) g/day in 2011–2012 (p = 0.012), but not among food insecure individuals (p = 0.816) and Supplemental Nutrition Assistance Program (SNAP) participants (p = 0.399). No differences in the odds of egg consumption were observed by income level, food security status, or SNAP participation status (p > 0.05 for all groups). Given the nutritional benefits of eggs, as well as their low cost and culinary versatility, the results presented here have important implications for reducing disparities in health outcomes and diet quality, in particular among food insecure individuals and SNAP participants. Further research is needed to examine factors that influence egg consumption and associated nutrient intake, and to identify potential barriers to increasing egg consumption, such as egg price changes, across diverse sociodemographic groups. PMID:28350345

Time Trends and Patterns of Reported Egg Consumption in the U.S. by Sociodemographic Characteristics.

PubMed

Conrad, Zach; Johnson, LuAnn K; Roemmich, James N; Juan, WenYen; Jahns, Lisa

2017-03-28

Eggs have the potential to contribute essential nutrients to nutritionally vulnerable populations on limited food budgets. Further research is needed to better understand patterns of egg consumption across diverse sociodemographic groups in order to inform clinical practice to improve nutrient adequacy. Data on demographics and egg intake of 29,694 U.S. adults were obtained from the National Health and Nutrition Examination Survey, 2001-2012. The National Cancer Institute's usual intake methodology was used to estimate the distribution of egg intake. Linear and logistic regression models were used to test for time trends in egg consumption and for differences between sociodemographic groups. The proportion of the U.S. population, overall (21%-22%; p = 0.311) and by sociodemographic group ( p > 0.05 for all groups), that reported consuming eggs remained unchanged from 2001 to 2012. Mean egg consumption increased overall from 23.0 (95% CI, 20.8-25.2) g/day in 2001-2002 to 25.5 (22.7-28.4) g/day in 2011-2012 ( p = 0.012), but not among food insecure individuals ( p = 0.816) and Supplemental Nutrition Assistance Program (SNAP) participants ( p = 0.399). No differences in the odds of egg consumption were observed by income level, food security status, or SNAP participation status ( p > 0.05 for all groups). Given the nutritional benefits of eggs, as well as their low cost and culinary versatility, the results presented here have important implications for reducing disparities in health outcomes and diet quality, in particular among food insecure individuals and SNAP participants. Further research is needed to examine factors that influence egg consumption and associated nutrient intake, and to identify potential barriers to increasing egg consumption, such as egg price changes, across diverse sociodemographic groups.

A SIMPLE AND EFFECTIVE MULTIPLEX PCR TECHNIQUE FOR DETECTING HUMAN PATHOGENIC TAENIA EGGS IN HOUSEFLIES.

PubMed

Pornruseetriratn, Siritavee; Maipanich, Wanna; Sa-nguankiat, Surapol; Pubampen, Somchit; Poodeepiyasawat, Akkarin; Thaenkham, Urusa

2017-01-01

Taenia solium, T. saginata, and T. asiatica are cestode pathogens causing taeniasis in humans. Houseflies can transfer Taenia eggs to food. However, houseflies are thought to carry only small numbers of Taenia eggs, sometimes fewer than 10. Although several PCR-based methods have been developed to detect Taenia DNA, these require more than 10 eggs for adequate detection. We developed a multiplex PCR method with high specificity for the discrimination among the eggs of the three Taenia species, T. solium, T. saginata, and T. asiatica, using 18S ribosomal DNA (rDNA) as a genetic marker. This technique was found to be highly sensitive, capable of identifying the Taenia species from only one egg. This multiplex PCR technique using 18S rDNA specific primers should be suitable to diagnose Taenia eggs.

Development of eggs and larvae of Emmelichthys nitidus (Percoidei: Emmelichthyidae) in south-eastern Australia, including a temperature-dependent egg incubation model

NASA Astrophysics Data System (ADS)

Neira, Francisco J.; Keane, John P.; Lyle, Jeremy M.; Tracey, Sean R.

2008-08-01

Reared eggs and field-collected material were employed to describe the development of the pelagic eggs and larvae of Emmelichthys nitidus (Emmelichthyidae), a small (36 cm TL) mid-water schooling species common in shelf waters of temperate Australia. Hydrated oocytes from adults trawled from spawning grounds off eastern Tasmania were fertilized and reared to the yolk-sac larval stage, and the data employed to build a temperature-dependent egg incubation model. Embryogenesis lasted 96, 84 and 54 h at mean temperatures of 13.1, 14.4 and 16.5 °C respectively, and was divided into seven stages based on extent of epiboly until blastopore closure (stages I-III) and embryo growth (stages IV-VII). Eggs (1.00-1.05 mm diameter) are spherical with a smooth chorion, small perivitelline space and prominent, unsegmented yolk with a single, posteriorly-located oil globule (0.18-0.20 mm diameter) that becomes pigmented from stage III. Embryos have two distinct snout melanophores, and a paired melanophore row laterally along the trunk and tail. Morphological identification of eggs collected during surveys in October 2005 and 2006 was validated using quantitative PCR amplification of the mtDNA d-loop gene region unique to E. nitidus, producing an 80-100% agreement across all seven stages. Newly-emerged larvae (1.9-3.3 mm) possess a prominent yolk sac with the posteriorly-located, pigmented oil globule, mouth not yet functional and unpigmented eyes. Notochord flexion occurs between 5 and 8 mm while fins are formed by 12 mm. Larvae examined (3.3-17.4 mm) are lightly pigmented and possess percoid features such as an elongate to moderate body, coiled, triangular-shaped gut, preopercular spines and 24-25 myomeres; two prominent pigment patches opposite each other dorsally and ventrally along the tail are diagnostic. Variability of mean egg ages ( y) by temperature ( t) and stage ( i) was best described by the deterministic stage-to-age model y = 35.911exp[-(0.155 t + 0.262 i)] i2.436. Developmental changes and model outputs paralleled those reported for laboratory-reared eggs of known clupeoids and scombrids, whereby hatching time and transition periods between stages decrease with increasing temperatures. The suitability of the incubation model to assign ages to staged field-caught eggs of E. nitidus is discussed in terms of its application to estimate spawning biomass using the daily egg production method.

Use of sodium dodecyl sulfate pretreatment and 2-stage curing for improved quality of salted duck eggs.

PubMed

Lian, Zixuan; Qiao, Longshan; Zhu, Guanghong; Deng, Yun; Qian, Bingjun; Yue, Jin; Zhao, Yanyun

2014-03-01

The effects of use of sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing on the microbial, physicochemical, and microstructural qualities of salted duck eggs were studied. After pretreatment in 0.5% (w/v) SDS solution at room conditions for 15 min, no discolorations were observed and no microorganisms were detected on the egg shells. In the 2-stage curing process, 25% (w/v) and 30% (w/v) saline solutions were evaluated in the 1st step (Stage I, approximately 18 d), whereas 4% (w/v) saline solution was applied in the 2nd step (Stage II, approximately 15 d). Along with increased curing time, water content decreased and NaCl content increased in the egg yolks from approximately 0.40% to 0.86%, whereas the water content of egg albumen remained at approximately 85% during the 2-stage curing. More importantly, the NaCl content of albumen maintained at approximately 4.0% at Stage II curing. Yolk index as a sign of maturity for salted duck eggs reached 1 at the end of Stage I (18 d) and retained the same value during Stage II curing regardless of the NaCl concentration in the Stage I saline solution. Oil exudation in egg yolks increased as the time of curing increased. As seen from scanning electron microscopy, oil was released from yolk granules. This study indicated that SDS pretreatment is effective to reduce microbial load on the shells of fresh duck eggs and the 2-stage curing can improve physicochemical qualities of the salted duck eggs and shortened curing time to about 7 to 17 d as compared to the traditional 1-step curing method. Spoiled saline solution and uneven distribution of salt are the 2 major problems in producing salted duck eggs. Sodium dodecyl sulfate (SDS) pretreatment and 2-stage curing process have shown effective to solve these problems, respectively. The SDS pretreatment was able to remove microorganisms and soil from the surface of fresh egg shells, thus preventing the spoilage of the saline solution. The 2-stage curing process successfully controlled the NaCl content of egg albumen and yolk in the final product, and shortened the curing time compared to the traditional 1-step curing method. © 2014 Institute of Food Technologists®

Egg serpins: The chicken and/or the egg dilemma.

PubMed

Dombre, Clara; Guyot, Nicolas; Moreau, Thierry; Monget, Philippe; Da Silva, Mylène; Gautron, Joël; Réhault-Godbert, Sophie

2017-02-01

Twenty-seven serpins belonging to clade A, B, C, D, E, F, G, H and I serpins are currently referenced in chicken genome databases. Phylogenetic analysis of chicken serpins revealed that ovalbumin (Serpinb14) and its paralogs ovalbumin-related protein Y (Serpinb14b) and ovalbumin-related protein X (Serpinb14c) are found in bird species. These clade B serpins are specifically expressed in reproductive tissues and exported in the egg where they constitute major protein components. These data suggest that these three paralogs have probably appeared in birds to face new environments and ensure the extra-uterine development of an embryo in a shell egg. Twelve other serpins have been identified in the newly produced egg, some of them having a specific distribution in the respective egg structures (eggshell, egg white, vitelline membrane and egg yolk). The physiological role of these egg serpins remain largely unexplored, but there is increasing evidence in literature or by homologies with their mammalian counterparts, that some of them participate in cell proliferation, tissue remodeling and/or angiogenesis associated with folliculogenesis and development of extraembryonic structures, eggshell biomineralization, egg defense and nutrition of the embryo. A better knowledge of the phylogenetic evolution of these 15 serpins in other oviparous species, on their egg distribution, on their regulation during embryonic development (activation/degradation/transfer) and on their functional specificity, is needed to better appreciate their role and their bird-specificity. These review shed light on the multiple possibilities that offer the avian egg model to study the role of serpins in reproduction and developmental biology. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Measles-Mumps-Rubella vaccine for children with egg allergy: Is admission for inpatient vaccination necessary?

PubMed

Tan, M S; Teoh, E J; Hor, C P; Yeoh, A A C

2016-08-01

Children who develop any hypersensitivity reaction to eggs are routinely referred to hospital for Measles-Mumps-Rubella (MMR) vaccination as inpatients to prevent anaphylaxis. We aimed to study the association between hypersensitivity reactions after egg exposure and similar reactions after MMR immunisation; and examine the necessity of hospital admission for vaccination. A prospective observational study was conducted in Paediatric Department in Bukit Mertajam Hospital, Penang, between March and December 2014. Children referred from local polyclinics for inpatient MMR vaccination because of a history of egg allergy were recruited. The children were observed in the ward for post vaccination allergic reactions. Concurrently, a group of children without egg allergy was recruited from those admitted for other illnesses but had recent MMR vaccination at polyclinics. Parents of these children were interviewed and asked if they had observed any reactions post vaccination. In both groups, sociodemographics, medical history and family history of atopy were collected. Eighty-seven subjects were recruited in this study. Fifty-four infants with egg allergy had previous mild allergic reactions after exposure to eggs or egg-related products. They were associated with a family history of egg hypersensitivity, personal history of acute gastroenteritis and upper respiratory tract infections. Two of them developed cutaneous rashes post vaccination during observation, but none developed anaphylactic or anaphylactoid reactions. Two infants among those without egg allergy had post vaccination fever. There was no association between egg allergy and hypersensitivity reactions to MMR vaccine (p=0.632). MMR vaccine can be safely administered to children with mild egg allergy, hence admission for vaccination in the hospital is not warranted. Risk stratification is required to ensure only infants with severe reactions will be admitted for vaccination.

Stage selection and restricted oviposition period improves cryopreservation of dipteran embryos.

PubMed

Rajamohan, Arun; Rinehart, Joseph P; Leopold, Roger A

2015-04-01

Embryos of two dipteran species (Musca domestica and Lucilia sericata) were assessed for an effective sampling time that would result in the highest post-cryopreservation hatch rate, with a primary goal to define species-specific egg collection periods and the effects of manual stage selection on post cryopreservation yield. The effects of the time taken to collect eggs on, (a) the proportion of embryos reaching a specific developmental stage between 17 and 20 h of development, and (b) the post-cryopreservation hatch rate were assessed. Permeabilization treatment applied at any stage of embryonic development did not significantly reduce embryo viability. Eggs collected over longer durations significantly reduced the number of embryos available in a specific developmental stage amenable to cryopreservation. Hatch percentage after cryopreservation of the embryos of M. domestica collected over a 60 min period was 10.7 ± 8.7% compared to 31 ± 5% for the eggs collected for just 15 min. Similarly, percent hatch in L. sericata resulted in 17.0 ± 3.9 and <2% for 15 and 60 min samples, respectively. Significantly higher hatching rates were obtained for cryopreservation after manual selection of specific embryonic developmental stages from the dechorionated samples. Post-cryopreservation hatching rate for stage-selected M. domestica embryos was 86.5 ± 5.5% compared to 33.3 ± 4.5% for embryos staged only by an overall visual confirmation. In the case of L. sericata, the hatching percentage was 79.0 ± 11.1 for stage-selected embryos compared to 17.0 ± 3.9% without individual selection. Published by Elsevier Inc.

Amphibian fertilization and development in microgravity

NASA Technical Reports Server (NTRS)

Souza, K. A.; Black, S. D.

1985-01-01

An experiment investigating the effects of gravity on embryonic development in amphibians is proposed. The planned procedures for the preparation of the frog eggs for launching in the Space Shuttle, for the injection of the eggs with gonadotropin, for the insertion of the eggs into egg chambers, for the storage of one of the chambers in a microgravity area and the second into a centrifuge, and for the fertilization of the eggs are described. The later organogenesis, swimming behavior, cytoplasmic components, cellular formation, neural plate and archenteron expansion, and allometry and expansion of the organ systems will be examined. Normal morphology for embryos and tadpoles developing at microgravity and the formation of the neural plate opposite the sperm entry point meridian are predicted.

Among-sibling differences in the phenotypes of juvenile fish depend on their location within the egg mass and maternal dominance rank

PubMed Central

Burton, Tim; Hoogenboom, M. O.; Beevers, N. D.; Armstrong, J. D.; Metcalfe, N. B.

2013-01-01

We investigated whether among-sibling differences in the phenotypes of juvenile fish were systematically related to the position in the egg mass where each individual developed during oogenesis. We sampled eggs from the front, middle and rear thirds of the egg mass in female brown trout of known dominance rank. In the resulting juveniles, we then measured traits that are related to individual fitness: body size, social status and standard metabolic rate (SMR). When controlling for differences among females in mean egg size, siblings from dominant mothers were initially larger (and had a lower mass-corrected SMR) if they developed from eggs at the rear of the egg mass. However, heterogeneity in the size of siblings from different positions in the egg mass diminished in lower-ranking females. Location of the egg within the egg mass also affected the social dominance of the resulting juvenile fish, although the direction of this effect varied with developmental age. This study provides the first evidence of a systematic basis for among-sibling differences in the phenotypes of offspring in a highly fecund organism. PMID:23193132

Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones

NASA Astrophysics Data System (ADS)

Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

2012-12-01

We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

Phosphine resistance does not confer cross-resistance to sulfuryl fluoride in four major stored grain insect pests.

PubMed

Jagadeesan, Rajeswaran; Nayak, Manoj K

2017-07-01

Susceptibility to phosphine (PH 3 ) and sulfuryl fluoride (SF) and cross-resistance to SF were evaluated in two life stages (eggs and adults) of key grain insect pests, Rhyzopertha dominca (F.), Sitophilus oryzae (L.), Cryptolestes ferrugineus (Stephens), and Tribolium castaneum (Herbst). This study was performed with an aim to integrate SF into phosphine resistance management programmes in Australia. Characterisation of susceptibility and resistance to phosphine in eggs and adults showed that C. ferrugineus was the most tolerant as well as resistant species. Mortality responses of eggs and adults to SF at 25 °C revealed T. castaneum to be the most tolerant species followed by S. oryzae, C. ferrugineus and R. dominica. A high dose range of SF, 50.8-62.2 mg L -1 over 48 h, representing c (concentration) × t (time) products of 2438-2985 gh m -3 , was required for complete control of eggs of T. castaneum, whereas eggs of the least tolerant R. dominca required only 630 gh m -3 for 48 h (13.13 mg L -1 ). Mortality response of eggs and adults of phosphine-resistant strains to SF in all four species confirmed the lack of cross-resistance to SF. Our research concludes that phosphine resistance does not confer cross-resistance to SF in grain insect pests irrespective of the variation in levels of tolerance to SF itself or resistance to phosphine in their egg and adult stages. While our study confirms that SF has potential as a 'phosphine resistance breaker', the observed higher tolerance in eggs stresses the importance of developing SF fumigation protocols with longer exposure periods. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Offspring sex in a TSD gecko correlates with an interaction between incubation temperature and yolk steroid hormones.

PubMed

Ding, Guo-Hua; Yang, Jing; Wang, Jin; Ji, Xiang

2012-12-01

We incubated eggs of the Japanese gecko Gekko japonicus at three temperatures, and measured yolk testosterone (T) and 17β-estradiol (E2) levels at three time points in embryonic development (oviposition, 1/3 of incubation, and 2/3 of incubation), to examine whether maternal influence on offspring sex via yolk steroid hormone deposition is significant in the species. Eggs incubated at 24 °C and 32 °C produced mostly females, and eggs incubated at 28 °C almost a 50:50 sex ratio of hatchlings. Female-producing eggs were larger than male-producing eggs. Clutches in which eggs were incubated at the same temperature produced mostly same-sex siblings. Yolk T level at laying was negatively related to eggs mass, and yolk E2/T ratio was positively related to egg mass. Results of two-way ANOVA with incubation temperature and stage as the factors show that: yolk E2 level was higher at 32 °C than at 24 °C; yolk T level was higher, whereas yolk E2/T ratio was smaller, at 28 °C than at 24 °C; yolk E2 and T levels were higher at 2/3 than at 1/3 of incubation. Our data in G. japonucus show that: (1) maternal influence on offspring sex via yolk steroid hormone deposition is significant; (2) incubation temperature affects the dynamics of developmental changes in yolk steroid hormones; (3) influences of yolk steroid hormones on offspring sex are secondary relative to incubation temperature effects; and (4) offspring sex correlates with an interaction between incubation temperature and yolk steroid hormones.

Automated parasite faecal egg counting using fluorescence labelling, smartphone image capture and computational image analysis.

PubMed

Slusarewicz, Paul; Pagano, Stefanie; Mills, Christopher; Popa, Gabriel; Chow, K Martin; Mendenhall, Michael; Rodgers, David W; Nielsen, Martin K

2016-07-01

Intestinal parasites are a concern in veterinary medicine worldwide and for human health in the developing world. Infections are identified by microscopic visualisation of parasite eggs in faeces, which is time-consuming, requires technical expertise and is impractical for use on-site. For these reasons, recommendations for parasite surveillance are not widely adopted and parasite control is based on administration of rote prophylactic treatments with anthelmintic drugs. This approach is known to promote anthelmintic resistance, so there is a pronounced need for a convenient egg counting assay to promote good clinical practice. Using a fluorescent chitin-binding protein, we show that this structural carbohydrate is present and accessible in shells of ova of strongyle, ascarid, trichurid and coccidian parasites. Furthermore, we show that a cellular smartphone can be used as an inexpensive device to image fluorescent eggs and, by harnessing the computational power of the phone, to perform image analysis to count the eggs. Strongyle egg counts generated by the smartphone system had a significant linear correlation with manual McMaster counts (R(2)=0.98), but with a significantly lower coefficient of variation (P=0.0177). Furthermore, the system was capable of differentiating equine strongyle and ascarid eggs similar to the McMaster method, but with significantly lower coefficients of variation (P<0.0001). This demonstrates the feasibility of a simple, automated on-site test to detect and/or enumerate parasite eggs in mammalian faeces without the need for a laboratory microscope, and highlights the potential of smartphones as relatively sophisticated, inexpensive and portable medical diagnostic devices. Copyright © 2016 Australian Society for Parasitology. Published by Elsevier Ltd. All rights reserved.

Extraction and Analysis of V-Type Agents (VX, RVX, CVX, and VM) from Various Food Matrices by Ultra-Performance Liquid Chromatography-Time-Of-Flight Mass Spectrometry

DTIC Science & Technology

2015-12-01

2% reduced fat milk, Egg Beaters egg whites, tomato sauce, and several meats, including hamburger meat (80% lean and 20% fat), hot dogs, chicken... Egg Whites and Tomato Sauce .....................................................3 2.3.3 Group 3: Hot Dogs, Chicken Nuggets, Turkey Deli Meat...Apple juice, orange juice, whole milk, 2% reduced fat milk, Egg Beaters processed egg whites, tomato sauce, precooked turkey deli meat (99% fat free

Nematode development after removal of egg cytoplasm: absence of localized unbound determinants.

PubMed

Laufer, J S; von Ehrenstein, G

1981-01-23

Embryos of Caenorhabditis elegans develop into fertile adults after cell fragments, containing presumptive cytoplasm of somatic and germ line precursors, are extruded from uncleaved eggs or early blastomeres through laser-induced holes in the eggshells. This suggests that the determinate development of this worm is not dependent on the prelocalization of determinants in specific regions of the egg cytoplasm.

Does magnesium hardness in hatching waters affect the fertilization and hatching success of hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

Embryonic development is deemed to be the most sensitive stage in the life cycle of a teleost. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on egg development and embryo survival. Ca2+ and Mg2+ contribute to water har...

Egg size matching by an intraspecific brood parasite

USGS Publications Warehouse

Lemons, Patrick R.; Sedinger, James S.

2011-01-01

Avian brood parasitism provides an ideal system with which to understand animal recognition and its affect on fitness. This phenomenon of laying eggs in the nests of other individuals has classically been framed from the perspective of interspecific brood parasitism and host recognition of parasitic eggs. Few examples exist of strategies adopted by intraspecific brood parasites to maximize success of parasitic eggs. Intraspecific brood parasitism within precocial birds can be a risky strategy in that hatch synchrony is essential to reproductive success. Given that egg size is positively correlated with incubation time, parasitic birds would benefit by recognizing and selecting hosts with a similar egg size. Intraspecific brood parasitism is an alternative reproductive strategy in black brant (Branta bernicla nigricans), a colonial nesting goose with precocial young. Based on a randomization test, parasitic eggs in this study differed less in size from eggs in their host's nests than did random eggs placed in random nests. Parasitic eggs were remarkably similar in size to hosts’ eggs, differing by <2% of volume on average from host eggs, whereas randomly paired eggs in random nests differed by nearly 8%. The precision with which parasitic brant match the egg size of hosts in our study supports our hypothesis that brant match egg size of hosts, thereby maximizing hatching success of their parasitic eggs.

Ballistocardiogram of avian eggs determined by an electromagnetic induction coil.

PubMed

Ono, H; Akiyama, R; Sakamoto, Y; Pearson, J T; Tazawa, H

1997-07-01

As an avian embryo grows within an eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat. A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure the cardiogenic ballistic movement of the egg or ballistocardiogram (BCG). In this context, there is interest in using an electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system. Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs, indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of the velocity of egg movements.

As the Egg Turns: Monitoring Egg Attendance Behavior in Wild Birds Using Novel Data Logging Technology

PubMed Central

Shaffer, Scott A.; Clatterbuck, Corey A.; Kelsey, Emma C.; Naiman, Alex D.; Young, Lindsay C.; VanderWerf, Eric A.; Warzybok, Pete; Bradley, Russell; Jahncke, Jaime; Bower, Geoff C.

2014-01-01

Egg turning is unique to birds and critical for embryonic development in most avian species. Technology that can measure changes in egg orientation and temperature at fine temporal scales (1 Hz) was neither readily available nor small enough to fit into artificial eggs until recently. Here we show the utility of novel miniature data loggers equipped with 3-axis (i.e., triaxial) accelerometers, magnetometers, and a temperature thermistor to study egg turning behavior in free-ranging birds. Artificial eggs containing egg loggers were deployed in the nests of three seabird species for 1–7 days of continuous monitoring. These species (1) turned their eggs more frequently (up to 6.5 turns h−1) than previously reported for other species, but angular changes were often small (1–10° most common), (2) displayed similar mean turning rates (ca. 2 turns h−1) despite major differences in reproductive ecology, and (3) demonstrated distinct diurnal cycling in egg temperatures that varied between 1.4 and 2.4°C. These novel egg loggers revealed high-resolution, three-dimensional egg turning behavior heretofore never measured in wild birds. This new form of biotechnology has broad applicability for addressing fundamental questions in avian breeding ecology, life history, and development, and can be used as a tool to monitor birds that are sensitive to disturbance while breeding. PMID:24887441

Aggregation protects flexible-shelled reptile eggs from severe hydric stress.

PubMed

Marco, Adolfo; Díaz-Paniagua, Carmen

2008-03-01

Many reptiles lay eggs with flexible shells that can progressively lose water until lethal dehydration under dry soil conditions. The number of eggs that develop together may influence the water exchange in the nest. We hypothesise that egg aggregation could reduce water lost under dry conditions. We exposed aggregated and isolated eggs to severe hydric stress followed by a period of rehydration. Hydric stress caused a general loss of water in common chameleon eggs. Initial egg mass did not affect survival but eggs that had lost more water had higher mortality and produced smaller hatchlings. Mass loss was higher and even lethal for isolated Chamaeleo chameleon eggs. However, aggregated eggs lost less water and most survived this period. After hydric stress, all surviving eggs gained mass via water absorption, and aggregation negatively affected water uptake. Isolated eggs hatched at smaller sizes than aggregated eggs. Aggregation also favoured hatching synchrony. Large clutches may favour hatching success of terrestrial flexible-shelled eggs incubated under severe drought conditions.

Diurnal fluctuations in nematode egg excretion in naturally and in experimentally infected chickens.

PubMed

Wongrak, Kalyakorn; Gauly, Matthias; Daş, Gürbüz

2015-03-15

We investigated whether nematode egg excretion through feces of naturally or experimentally infected chickens follow certain patterns within a day, which may allow determining the most appropriate sampling time for the highest parasite egg concentration. Feces samples (n=864) from chickens (n=36) with naturally occurring mixed nematode infections (trials N1, N2) or with an experimental Ascaridia galli infection (E) were collected quantitatively every 4h for four consecutive days. Number of eggs per gram of feces (EPG) was determined, and accumulative egg output (AEO) at each sampling time as well as total number of eggs excreted within 24h (eggs per day, EPD) were then estimated. At the end of the collection period, the hens were necropsied and their worm burdens determined. Naturally infected hens harbored Heterakis gallinarum (100%), Capillaria spp. (95.7%) and A. galli (91.3%). The experimental A. galli infection produced patent infections in all the birds. In general, both fecal egg concentration (EPG) and the amount of feces increased (P<0.05) sharply from the early morning to early-noon (10:00 a.m.) and remained at a high level until evenings which thereafter decreased to their initial levels during the night both in naturally and experimentally infected birds. This resulted in a more apparent increase or a decrease in AEO at the corresponding time points, respectively, and led to much higher egg excretions during the daytime than the nights. Despite the apparent within day fluctuations in egg excretion, neither EPG (P=0.704) nor AEO (P=0.499) nor EPD (P=0.149) was significantly different among the four collection days. Similarly, there was no significant interaction (P>0.05) between effects of sampling hours and days on EPG and AEO, suggesting the existence of repeatable diurnal fluctuations within each day. Although an association between climatic parameters (e.g., ambient temperature and relative humidity) and the nematode egg excretion was quantified, a causal relationship could not be demonstrated. We conclude that nematode egg excretion through chicken feces in both natural and experimental infections shows repeatable diurnal fluctuations, which may indicate adaptive strategies by nematodes and eventually favor parasite spread. Since analytic sensitivity of fecal egg counts suffers from low egg concentrations in feces, samples taken during the daytime have a higher diagnostic value. Copyright © 2015 Elsevier B.V. All rights reserved.

Experimental parameterisation of principal physics in buoyancy variations of marine teleost eggs.

PubMed

Jung, Kyung-Mi; Folkvord, Arild; Kjesbu, Olav Sigurd; Sundby, Svein

2014-01-01

It is generally accepted that the high buoyancy of pelagic marine eggs is due to substantial influx of water across the cell membrane just before ovulation. Here we further develop the theoretical basis by applying laboratory observations of the various components of the fertilized egg in first-principle equations for egg specific gravity (ρ(egg)) followed by statistical validation. We selected Atlantic cod as a model animal due to the affluent amount of literature on this species, but also undertook additional dedicated experimental works. We found that specific gravity of yolk plus embryo is central in influencing ρ(egg) and thereby the buoyancy. However, our established framework documents the effect on ρ(egg) of the initial deposition of the heavy chorion material in the gonad prior to spawning. Thereafter, we describe the temporal changes in ρ(egg) during incubation: Generally, the eggs showed a slight rise in ρ(egg) from fertilization to mid-gastrulation followed by a gradual decrease until full development of main embryonic organs just before hatching. Ontogenetic changes in ρ(egg) were significantly associated with volume and mass changes of yolk plus embryo. The initial ρ(egg) at fertilization appeared significantly influenced by the chorion volume fraction which is determined by the combination of the final chorion volume of the oocyte and of the degree of swelling (hydrolyzation) prior to spawning. The outlined principles and algorithms are universal in nature and should therefore be applicable to fish eggs in general.

Experimental Parameterisation of Principal Physics in Buoyancy Variations of Marine Teleost Eggs

PubMed Central

Jung, Kyung-Mi; Folkvord, Arild; Kjesbu, Olav Sigurd; Sundby, Svein

2014-01-01

It is generally accepted that the high buoyancy of pelagic marine eggs is due to substantial influx of water across the cell membrane just before ovulation. Here we further develop the theoretical basis by applying laboratory observations of the various components of the fertilized egg in first-principle equations for egg specific gravity (ρegg) followed by statistical validation. We selected Atlantic cod as a model animal due to the affluent amount of literature on this species, but also undertook additional dedicated experimental works. We found that specific gravity of yolk plus embryo is central in influencing ρegg and thereby the buoyancy. However, our established framework documents the effect on ρegg of the initial deposition of the heavy chorion material in the gonad prior to spawning. Thereafter, we describe the temporal changes in ρegg during incubation: Generally, the eggs showed a slight rise in ρegg from fertilization to mid-gastrulation followed by a gradual decrease until full development of main embryonic organs just before hatching. Ontogenetic changes in ρegg were significantly associated with volume and mass changes of yolk plus embryo. The initial ρegg at fertilization appeared significantly influenced by the chorion volume fraction which is determined by the combination of the final chorion volume of the oocyte and of the degree of swelling (hydrolyzation) prior to spawning. The outlined principles and algorithms are universal in nature and should therefore be applicable to fish eggs in general. PMID:25122447

Artificial induction of mito-gynogenetic diploids in large yellow croaker ( Pseudosciaena crocea) by hydrostatic pressure

NASA Astrophysics Data System (ADS)

Cai, Mingyi; Wu, Qingming; Liu, Xiande; Yao, Cuiluan; Chen, Qingkai; Wang, Zhiyong

2010-07-01

The present study investigated conditions for inducing mito-gynogenetic (endomitosis) diploids by hydrostatic pressure in the large yellow croaker Pseudosciaena crocea. In haploid control groups, the development of eggs was activated with ultraviolet radiated semen. All fry presented typical haploid syndrome in the haploid control groups, and were verified as haploids using cytometry. After hydrostatic pressure treatment, morphologically normal fry reappeared at different frequencies according to the intensity and time of pressure shock. Fry with normal appearance in the pressure treated groups were verified as gynogenetic double haploids (GDHs), containing only one allele from the female parent at all four diagnostic microsatellite loci. For a fixed duration of 3 min, the optimal intensity of blocking the first mitosis was determined to be 40 Mpa, which was similar to that of blocking the second meiosis. There was a “window” of starting time, from 36.1 min to 38.1 min post-insemination at 25.0±1.0°C, within which the production of GDHs was not significantly different. Maximum production of morphologically normal fries, 9.36%±2.97% of developed eggs, was found when the eggs were shocked with hydrostatic pressure at 40 Mpa for 3 min, starting from 38.1 min post insemination at 25.0±1.0°C.

Distributed Egg Production Functions for Meloidogyne arenaria in Grape Varieties and Consideration of the Mechanistic Relationship between Plant and Parasite.

PubMed

Ferris, H; Schneider, S M; Semenoff, M C

1984-04-01

Nematode egg production rates, as mediated by environmental conditions and host status, are important determinants of population development. Rates of egg production by Meloidogyne arenaria varied from 0.48 to 1.0 egg per female per DD (degree days above 10 C) in different grape varieties. The length of the egg production period ranged from 550 to 855 DD where measurable, and was generally longer in those varieties where the production rate was slow. We hypothesize that if a successful infection site is established, a constant number of eggs is produced if favorable environmental conditions prevail. Mechanistic coupling structures between plant growth and nematode population models are formulated. The nematode population influences metabolite supply through its effect on physiological efficiency and also acts as a metabolic sink; the degree of plant physiological stress influences nematode population development by affecting the sex ratio and egg production rates.

A nonlethal microsampling technique to monitor the effects of mercury on wild bird eggs

USGS Publications Warehouse

Stebbins, Katherine R.; Klimstra, Jon D.; ,; Ackerman, Joshua T.; Heinz, Gary

2009-01-01

Methylmercury is the predominant chemical form of mercury reported in the eggs of wild birds, and the embryo is the most sensitive life stage to methylmercury toxicity. Protective guidelines have been based mainly on captive-breeding studies with chickens (Gallus gallus), mallards (Anas platyrhynchos), and ring-necked pheasants (Phasianus colchicus) or on field studies where whole eggs were collected and analyzed and the effects of the mercury were measured based on the reproductive success of the remaining eggs. However, both of these methods have limitations. As an alternative, we developed a technique that involves extracting a small sample of albumen from a live egg, sealing the egg, returning the egg to its nest to be naturally incubated by the parents, and then relating the hatching success of this microsampled egg to its mercury concentration. After first developing this technique in the laboratory using chicken and mallard eggs, we selected the laughing gull (Larus atricilla) and black-necked stilt (Himantopus mexicanus) as test subjects in the field. We found that 92% of the microsampled laughing gull eggs met our reproductive endpoint of survival to the beginning of hatching compared to 100% for the paired control eggs within the same nests. Microsampled black-necked stilt eggs exhibited 100% hatching success compared to 93% for the paired control eggs. Our results indicate that microsampling is an effective tool for nonlethally sampling mercury concentrations in eggs and, as such, can be used for monitoring sensitive species, as well as for improving studies that examine the effects of mercury on avian reproduction.

Advanced Oxidation Process sanitation of hatching eggs reduces Salmonella in broiler chicks

USDA-ARS?s Scientific Manuscript database

Reduction of Salmonella contamination of eggs is important in improving the microbial food safety of poultry and poultry products. Developing interventions to reduce Salmonella contamination of eggs is important to improving the microbial quality of eggs entering the hatchery. Previously, the hydr...

The effect of low-density diets on broiler breeder performance during the laying period and on embryonic development of their offspring.

PubMed

Enting, H; Kruip, T A M; Verstegen, M W A; van der Aar, P J

2007-05-01

The effect of low-density diets on bird performance, egg composition, and embryonic development was studied with 2,100 female and 210 male Cobb broiler breeders from 25 to 60 wk of age. The experiment included 5 treatments. These included a control group with a normal density diet (ND, 2,800 kcal of AME/kg). Treatments 2 (LD11) and 3 (LD21) had a 11 and 21% lower nutrient density. Treatment 4 (LD11(OP)) had a 11% less dense diet, which was obtained by inclusion of other feed ingredients. In these 4 treatments similar diets were given during the rearing and the laying period. Treatment 5 combined LD12 in the rearing period and ND diets during the laying period (LD12-ND). Egg composition and embryonic development were measured in eggs of ND and LD21 birds at 29 and 41 wk of age. During the laying period from wk 25 to 60, live weights did not differ among treatments, except that birds fed LD11(OP) had lower live weights. A significantly higher rate of lay was provided by LD11 compared with ND. Egg weights were significantly higher when low-density diets were fed, particularly in LD11(OP). Percentage of fertile eggs did not differ among treatments. Compared with the other treatments, LD11(OP) provided a significantly lower hatchability. We found that LD21 resulted in a better development of the area vitellina externa and heart and embryo weight at 29 wk of age. It was concluded that this was related to a higher egg weight and egg white proportion. This suggests that the amount of egg white in eggs of hens fed ND was limiting for embryonic development, particularly in eggs of young broiler breeders.

Regulation of protein phosphatase 2A during embryonic diapause process in the silkworm, Bombyx mori.

PubMed

Gu, Shi-Hong; Hsieh, Hsiao-Yen; Lin, Pei-Ling

2017-11-01

Regulation of protein phosphorylation requires coordinated interactions between protein kinases and protein phosphatases. In the present study, we investigated regulation of protein phosphatase 2A (PP2A) during the embryonic diapause process of B. mori. An immunoblotting analysis showed that Bombyx eggs contained a catalytic C subunit, a major regulatory B subunit (B55/PR55 subunit), and a structural A subunit, with the A and B subunits undergoing differential changes between diapause and non-diapause eggs during embryonic process. In non-diapause eggs, eggs whose diapause initiation was prevented by HCl, and eggs in which diapause had been terminated by chilling of diapausing eggs at 5°C for 70days and then were transferred to 25°C, protein levels of the A and B subunits of PP2A gradually increased toward embryonic development. However, protein levels of the A and B subunits in diapause eggs remained at low levels during the first 8days after oviposition. The direct determination of PP2A enzymatic activity showed that the activity remained at low levels in diapause eggs during the first 8days after oviposition. However, in non-diapause eggs, eggs whose diapause initiation was prevented by HCl, and eggs in which diapause had been terminated by chilling, PP2A enzymatic activity sharply increased during the first several days, reached a peak during the middle embryonic development, and then greatly decreased 3 or 4days before hatching. Examination of temporal changes in mRNA expression levels of the catalytic β subunit and regulatory subunit of PP2A showed high levels in eggs whose diapause initiation was prevented by HCl compared to those in diapause eggs. These results demonstrate that the higher PP2A gene expression and PP2A A and B subunit protein levels and increased enzymatic activity are related to embryonic development of B. mori. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trans-shell infection by pathogenic micro-organisms reduces the shelf life of non-incubated bird's eggs: a constraint on the onset of incubation?

PubMed

Cook, Mark I; Beissinger, Steven R; Toranzos, Gary A; Rodriguez, Roberto A; Arendt, Wayne J

2003-11-07

Many birds initiate incubation before clutch completion, which results in asynchronous hatching. The ensuing within-brood size disparity often places later-hatched nestlings at a developmental disadvantage, but the functional significance of the timing of the onset of incubation is poorly understood. Early incubation may serve to maintain the viability of early-laid eggs, which declines over time owing to the putative effects of ambient temperature. An unexplored risk to egg viability is trans-shell infection by micro-organisms. We experimentally investigated the rate and magnitude of microbial trans-shell infection of the egg, and the relative effects of ambient temperature and micro-organisms on hatching success. We show that infection of egg contents is prevalent and occurs within the time required to lay a clutch. The probability of infection depends on the climatic conditions, the exposure period and the phylogenetic composition of the eggshell microbiota. We also demonstrate that microbial infection and ambient temperature act independently to reduce egg viability considerably. Our results suggest that these two factors could affect the onset of avian incubation in a wide range of environments.

Trans-shell infection by pathogenic micro-organisms reduces the shelf life of non-incubated bird's eggs: a constraint on the onset of incubation?

PubMed Central

Cook, Mark I; Beissinger, Steven R; Toranzos, Gary A; Rodriguez, Roberto A; Arendt, Wayne J

2003-01-01

Many birds initiate incubation before clutch completion, which results in asynchronous hatching. The ensuing within-brood size disparity often places later-hatched nestlings at a developmental disadvantage, but the functional significance of the timing of the onset of incubation is poorly understood. Early incubation may serve to maintain the viability of early-laid eggs, which declines over time owing to the putative effects of ambient temperature. An unexplored risk to egg viability is trans-shell infection by micro-organisms. We experimentally investigated the rate and magnitude of microbial trans-shell infection of the egg, and the relative effects of ambient temperature and micro-organisms on hatching success. We show that infection of egg contents is prevalent and occurs within the time required to lay a clutch. The probability of infection depends on the climatic conditions, the exposure period and the phylogenetic composition of the eggshell microbiota. We also demonstrate that microbial infection and ambient temperature act independently to reduce egg viability considerably. Our results suggest that these two factors could affect the onset of avian incubation in a wide range of environments. PMID:14613609

Preliminary results of the Artemia salina experiments in biostack on LDEF

NASA Technical Reports Server (NTRS)

Graul, E. H.; Ruether, W.; Hiendl, C. O.

1992-01-01

The mosaic egg of the brine shrimp, Artemia salina, resting in blastula or gastrula state represents a system that during further development, proceeds without any further development to the larval stage, the free swimming nauplius. Therefore, injury to a single cell of the egg will be manifest in the larvae. In several experiments, it was shown that the passage of a single heavy ion through the shrimp egg damaged a cellular area large enough to disturb either embryogenesis or further development of the larvae, or the integrity of the adult individual. Emergence from the egg shell was heavily disturbed by the heavy ions as was hatching. Additional late effects, due to a hit by a heavy ion, are delayed of growth and of sexual maturity, and reduced fertility. Anomalies in the body and the extremities could be observed more frequently for the nauplii which had developed from eggs hit by heavy ions.

Influence of clinostat rotation on fertilized amphibian egg pattern specification

NASA Technical Reports Server (NTRS)

Neff, A. W.; Smith, R. C.; Malacinski, G. M.; Chung, H.-M.

1984-01-01

Pattern specification in fertile Xenopus eggs rotated on horizontal clinostats was monitored with respect to primary embryonic axis formation, subsequent morphogenesis, and compartmentalization of the cytoplasm. At the speeds of 1 to 24 rpm (which are believed to simulate microgravity) a large percentage of eggs developed normal axial structures. Eggs clinostated at 12 rpm showed a randomization of dorsal/ventral polarity. The cytoplasmic compartments showed some clinostat effects but no abnormal mixing, disruption or dislocation of compartments. It is predicted that Xenopus eggs fertilized and allowed to develop in space will retain normal cytoplasmic density compartments, establish primary axes and undergo normal morphogenesis in space. Their dorsal/ventral polarity may not, however, be determined by the sperm entrance site (as is the case for 1 g eggs).

9 CFR 592.510 - Base time rate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Base time rate. 592.510 Section 592... PRODUCTS INSPECTION VOLUNTARY INSPECTION OF EGG PRODUCTS Fees and Charges § 592.510 Base time rate. The base time rate for voluntary inspection services for egg products is $47.79 per hour per program...

Egg clutch patterning in Lestes virens (Odonata, Lestidae) with evolutionary emphasis on endophytic oviposition in lestid dragonflies.

PubMed

Matushkina, Natalia A; Buy, Denis; Lambret, Philippe

2016-12-01

Egg deposition within plants is one of the most widely distributed and ancient behaviors in Odonata. The resulting clutch consists of eggs placed in peculiar pattern that can be a characteristic for certain groups of Odonata. Despite their importance for paleontological and evolutionary research, data on egg-clutch positioning are missing or insufficient for most species. Here, patterning of egg clutches in Lestes virens was measured and described in detail for the first time. The female usually produces a linear row of single eggs directed at an angle rightward or leftward to the longitudinal axis of plant substrate. Less often eggs are arranged in egg-sets consisting of up to 4 eggs. Apparently, the female insect follows the rigid behavior stereotypes during oviposition and is unable to easily switch to the alternate stereotypical behavior of single egg deposition or production of multiegg sets. Based on a literature review and original data, egg clutch patterning of European Lestidae is overlaid on preexisting phylogenies. The resulting evolutionary scenario of egg-clutch patterning can be considered in the framework of egg-laying behavior in Lestidae. © 2015 Institute of Zoology, Chinese Academy of Sciences.

Cryptic cuckoo eggs hide from competing cuckoos

PubMed Central

Gloag, Ros; Keller, Laurie-Anne; Langmore, Naomi E.

2014-01-01

Interspecific arms races between cuckoos and their hosts have produced remarkable examples of mimicry, with parasite eggs evolving to match host egg appearance and so evade removal by hosts. Certain bronze-cuckoo species, however, lay eggs that are cryptic rather than mimetic. These eggs are coated in a low luminance pigment that camouflages them within the dark interiors of hosts' nests. We investigated whether cuckoo egg crypsis is likely to have arisen from the same coevolutionary processes known to favour egg mimicry. We added high and low luminance-painted eggs to the nests of large-billed gerygones (Gerygone magnirostris), a host of the little bronze-cuckoo (Chalcites minutillus). Gerygones rarely rejected either egg type, and did not reject natural cuckoo eggs. Cuckoos, by contrast, regularly removed an egg from clutches before laying their own and were five times more likely to remove a high luminance model than its low luminance counterpart. Given that we found one-third of all parasitized nests were exploited by multiple cuckoos, our results suggest that competition between cuckoos has been the key selective agent for egg crypsis. In such intraspecific arms races, crypsis may be favoured over mimicry because it can reduce the risk of egg removal to levels below chance. PMID:25122227

Morphological Differentiation of the Eggs of North American Container-Inhabiting Aedes Mosquitoes.

PubMed

Bova, Jake; Paulson, Sally; Paulson, Greg

2016-09-01

Aedes aegypti , Ae. albopictus, Ae. japonicus japonicus, and Ae. triseriatus eggs are described with the aid of color images and images from scanning electron microscopy. All eggs were broadly cigar shaped with Ae. triseriatus and Ae. j japonicus eggs being dull or matte black, while Ae. albopictus and Ae. aegypti eggs were shiny jet black. Aedes triseriatus eggs were lighter in color and had a rougher appearance when compared to those of Ae. j. japonicus. Aedes albopictus and Ae. aegypti eggs can be differentiated by the distinct presence of micropylar collars in Ae. aegypti. Our results reduce the need to rear these mosquitoes, reducing labor and time while providing an accurate identification of the vector mosquitoes.

Comment on linking the sex difference in PCB concentrations of fish to release of eggs at spawning: Time to jettison the dogma

USGS Publications Warehouse

Madenjian, Charles P.

2017-01-01

For the past 20 years or so, a commonly used explanation in the scientific literature for higher polychlorinated biphenyl (PCB) concentrations in male fish than in female fish has been that females lose a high proportion of their PCB body burden by releasing eggs at spawning time, and therefore the females undergo a substantial decrease in their PCB concentration immediately after spawning due to shedding of their eggs [1]. Indeed, this explanation can be viewed as the conventional wisdom used by toxicologists to account for differences in PCB concentrations between the sexes of fish. On the surface, this explanation seems plausible. PCBs are lipid soluble, and eggs are thought to be relatively high in lipid concentration. If a sufficiently high proportion of the PCB body burden within a female fish is transferred to the eggs, then the release of eggs at spawning would be expected to result in a dramatic decrease in the PCB concentration of the female.

Immunologic changes in children with egg allergy ingesting extensively heated egg.

PubMed

Lemon-Mulé, Heather; Sampson, Hugh A; Sicherer, Scott H; Shreffler, Wayne G; Noone, Sally; Nowak-Wegrzyn, Anna

2008-11-01

Prior studies have suggested that heated egg might be tolerated by some children with egg allergy. We sought to confirm tolerance of heated egg in a subset of children with egg allergy, to evaluate clinical and immunologic predictors of heated egg tolerance, to characterize immunologic changes associated with continued ingestion of heated egg, and to determine whether a diet incorporating heated egg is well tolerated. Subjects with documented IgE-mediated egg allergy underwent physician-supervised oral food challenges to extensively heated egg (in the form of a muffin and a waffle), with tolerant subjects also undergoing regular egg challenges (in a form of scrambled egg or French toast). Heated egg-tolerant subjects incorporated heated egg into their diets. Skin prick test wheal diameters and egg white, ovalbumin, and ovomucoid IgE levels, as well as ovalbumin and ovomucoid IgG4 levels, were measured at baseline for all subjects and at 3, 6, and 12 months for those tolerant of heated egg. Sixty-four of 117 subjects tolerated heated egg, 23 tolerated regular egg, and 27 reacted to heated egg. Heated egg-reactive subjects had larger skin test wheals and greater egg white-specific, ovalbumin-specific, and ovomucoid-specific IgE levels compared with heated egg- and egg-tolerant subjects. Continued ingestion of heated egg was associated with decreased skin test wheal diameters and ovalbumin-specific IgE levels and increased ovalbumin-specific and ovomucoid-specific IgG4 levels. The majority of subjects with egg allergy were tolerant of heated egg. Continued ingestion of heated egg was well tolerated and associated with immunologic changes that paralleled the changes observed with the development of clinical tolerance to regular egg.

Facultative cardiac responses to regional hypoxia in lizard embryos.

PubMed

Du, Wei-Guo; Thompson, Michael B; Shine, Richard

2010-08-01

In natural nests, the eggs of squamate reptiles (lizards and snakes) sometimes experience unpredictable shifts in oxygen availability as a function of nest flooding, or the details of egg location within a nest. We experimentally investigated whether embryos can facultatively adjust cardiac function to cope with such challenges by imposing regional hypoxia on developing eggs of the scincid lizard Bassiana duperreyi. To do so, we sealed half of the eggshell surface with tissue adhesive. The embryos rapidly responded by increasing heart rates, which they maintained for long periods. The elevated heart rates enabled the embryos not only to survive, but to maintain "normal" metabolic rates, and to hatch at the usual time with unmodified phenotypic traits (e.g., hatchling size, relative heart mass, locomotor speed, post-hatchling survival and growth rates). Turtles and birds with rigid (highly calcified) eggshells show more dramatic ill-effects from hypoxic incubation, suggesting that the thin (and thus, highly gas-permeable) parchment-shelled eggs of most squamates allow more effective embryonic adjustment of oxygen exchange rates in response to externally-imposed hypoxia. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Prenatal stress in birds: pathways, effects, function and perspectives.

PubMed

Henriksen, Rie; Rettenbacher, Sophie; Groothuis, Ton G G

2011-06-01

Although most work on prenatal stress has been conducted on mammalian species, birds provide useful alternative models since avian embryos develop outside the mother's body in a concealed environment, the egg, which is produced during a short time window of 4-14 days. This facilitates measurement of maternal substances provided for and manipulation of the embryo without interfering with the mother's physiology. We critically review prenatal corticosterone mediated effects in birds by reviewing both studies were females had elevated levels of plasma corticosterone during egg formation and studies applying corticosterone injections directly into the egg. A selected review of the mammalian literature is used as background. The results suggest that besides prenatal exposure to corticosterone itself, maternal corticosterone affects offspring's behaviour and physiology via alteration of other egg components. However, results are inconsistent, perhaps due to the interaction with variation in the post-natal environment, sex, age, developmental mode and details of treatment. The potential role of adaptive maternal programming has not been tested adequately and suggestions for future research are discussed. Copyright © 2011. Published by Elsevier Ltd.

Integrating toxicity risk in bird eggs and chicks: using chick down feathers to estimate mercury concentrations in eggs.

PubMed

Ackerman, Joshua T; Eagles-Smith, Collin A

2009-03-15

The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5-32.4 microg g(-1) fw) and eggs (0.04-2.79 microg g(-1) fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n=94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n=28, r2 = 0.79). Down feather Hg in recaptured chicks (< or =10 days old) was correlated with down feather Hg at hatching (< or =3 days old; n=88, r2 = 0.74). Our results demonstrate the utility of using down feathers of chicks < or =10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg's effects on both egg hatchability and subsequent chick mortality.

Integrating toxicity risk in bird eggs and chicks: Using chick down feathers to estimate mercury concentrations in eggs

USGS Publications Warehouse

Ackerman, Joshua T.; Eagles-Smith, Collin A.

2009-01-01

The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5−32.4 μg g−1 fw) and eggs (0.04−2.79 μg g−1 fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n = 94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n = 28, r2 = 0.79). Down feather Hg in recaptured chicks (≤10 days old) was correlated with down feather Hg at hatching (≤3 days old; n = 88, r2 = 0.74). Our results demonstrate the utility of using down feathers of chicks ≤10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg’s effects on both egg hatchability and subsequent chick mortality.

Dirt detection on brown eggs by means of color computer vision.

PubMed

Mertens, K; De Ketelaere, B; Kamers, B; Bamelis, F R; Kemps, B J; Verhoelst, E M; De Baerdemaeker, J G; Decuypere, E M

2005-10-01

In the last 20 yr, different methods for detecting defects in eggs were developed. Until now, no satisfying technique existed to sort and quantify dirt on eggshells. The work presented here focuses on the design of an off-line computer vision system to differentiate and quantify the presence of different dirt stains on brown eggs: dark (feces), white (uric acid), blood, and yolk stains. A system that provides uniform light exposure around the egg was designed. In this uniform light, pictures of dirty and clean eggs were taken, stored, and analyzed. The classification was based on a few standard logical operators, allowing for a quick implementation in an online set-up. In an experiment, 100 clean and 100 dirty eggs were used to validate the classification algorithm. The designed vision system showed an accuracy of 99% for the detection of dirt stains. Two percent of the clean eggs had a light-colored eggshell and were subsequently mistaken for showing large white stains. The accuracy of differentiation of the different kinds of dirt stains was 91%. Of the eggs with dark stains, 10.81% were mistaken for having bloodstains, and 33.33% of eggs with bloodstains were mistaken for having dark stains. The developed system is possibly a first step toward an on line dirt evaluation technique for brown eggs.

Oviposition site choice under conflicting risks demonstrates that aquatic predators drive terrestrial egg-laying

PubMed Central

Touchon, Justin C.; Worley, Julie L.

2015-01-01

Laying eggs out of water was crucial to the transition to land and has evolved repeatedly in multiple animal phyla. However, testing hypotheses about this transition has been difficult because extant species only breed in one environment. The pantless treefrog, Dendropsophus ebraccatus, makes such tests possible because they lay both aquatic and arboreal eggs. Here, we test the oviposition site choices of D. ebraccatus under conflicting risks of arboreal egg desiccation and aquatic egg predation, thereby estimating the relative importance of each selective agent on reproduction. We also measured discrimination between habitats with and without predators and development of naturally laid aquatic and arboreal eggs. Aquatic embryos in nature developed faster than arboreal embryos, implying no cost to aquatic egg laying. In choice tests, D. ebraccatus avoided habitats with fish, showing that they can detect aquatic egg predators. Most importantly, D. ebraccatus laid most eggs in the water when faced with only desiccation risk, but switched to laying eggs arboreally when desiccation risk and aquatic predators were both present. This provides the first experimental evidence to our knowledge that aquatic predation risk influences non-aquatic oviposition and strongly supports the hypothesis that it was a driver of the evolution of terrestrial reproduction. PMID:25948689

Assessing the Total Mortality Caused by Two Species of Trichogramma on Its Natural Host Plutella xylostella (L.) at Different Temperatures.

PubMed

Marchioro, C A; Krechemer, F S; Foerster, L A

2015-06-01

Trichogramma pretiosum Riley and Trichogramma atopovirilia Oatman & Platner are natural enemies of Plutella xylostella (L.) in Southern Brazil. Laboratory studies to evaluate parasitoids performance under different conditions, such as temperature regimes, are necessary to assess their potential as biocontrol agents of P. xylostella. In most studies involving Trichogramma, parasitism rate is the main parameter used to evaluate parasitoid performance, ignoring that parasitoids can cause egg mortality by feeding on the host content and/or to multiple drilling without laying eggs. This study was conducted to investigate three main issues: how temperature affects T. pretiosum and T.atopovirilia development on eggs of P. xylostella, whether or not these species respond differently to temperature, and how important is the mortality they cause besides parasitism on P. xylostella. Temperature effects (from 10 to 30°C) on development, survival, parasitism rate, mortality, and total mortality caused by T. pretiosum and T. atopovirilia on eggs of P. xylostella were evaluated. Temperature affected the development time, female longevity, parasitism rate, mortality not directly related to parasitoid larval development, and total mortality caused on the host. No significant differences were recorded for the estimated thermal requirements for T. pretiosum and T. atopovirilia. However, the higher mortality caused by T. pretiosum indicates that this parasitoid is the most suitable to be used against P. xylostella. Also, the results suggest that the use of parasitism rate as the only parameter to evaluate the performance of T. pretiosum and T. atopovirilia may underestimate the potential of these parasitoids in regulating pest populations.

Effect of gluten, egg and soy proteins on the rheological and thermo-mechanical properties of wholegrain rice flour.

PubMed

Pătraşcu, Livia; Banu, Iuliana; Vasilean, Ina; Aprodu, Iuliana

2017-03-01

The effect of protein addition on the rheological, thermo-mechanical and baking properties of wholegrain rice flour was investigated. Gluten, powdered eggs and soy protein concentrate were first analyzed in terms of rheological properties, alone and in admixture with rice flour. The temperature ramp tests showed clear differences in the rheological behavior of the batters supplemented with different proteins. The highest thermal stability was observed in case of soy protein samples. Frequency sweep tests indicated significant improvements of the rheological properties of rice flour supplemented with 15% gluten or soy proteins. The thermo-mechanical tests showed that, due to the high fat contents and low level of free water, the dough samples containing powdered eggs exhibited the highest stability. Addition of gluten resulted in a significant decrease of the dough development time, whereas samples with powdered eggs and soy proteins were more difficult to hydrate. The incorporation of proteins into the rice flour-based dough formulations significantly affected starch behavior by decreasing the peak consistency values. Concerning the quality of the rice flour-based breads, soy protein addition resulted in lighter crumb color and increased texture attributes, samples with gluten had better resilience and adhesiveness, whereas breads with egg protein were less brittle.

Species-specific vulnerability of benthic marine embryos of congeneric snails (Haminoea spp.) to ultraviolet radiation and other intertidal stressors.

PubMed

Russell, Janine; Phillips, Nicole

2009-08-01

We used field surveys and multi-factorial experiments to examine synergistic effects of ultraviolet radiation (UVR) and low tide conditions on the embryonic mortality of two bubble-shell snail species that deposit gelatinous egg masses in intertidal mudflats: Haminoea zelandiae from New Zealand, and Haminoea vesicula from Washington, USA. Egg masses of both species were predominantly found in shallow pools at low tide, and a substantial proportion of both were found in sunny as well as shaded microhabitats. Both exposure to sun and desiccation led to increased embryonic mortality for naturally deposited egg masses of H. zelandiae compared to those that were shaded or submerged. For H. vesicula, although mortality was double for embryos within desiccated egg masses, there was no additional mortality due to sun exposure. In manipulative experiments, UVR and low tide conditions increased embryonic mortality for both species; however, H. zelandiae appeared to be more vulnerable to UVR, whereas H. vesicula was particularly vulnerable to desiccation. Simulated tidal pool conditions significantly increased mortality only for H. vesicula. These results suggest an important role of species-specific differences in vulnerability to different stressors, even for ecologically similar congeners; here, these differences may be related to development time or egg mass characteristics.

Thelytokous Parthenogenesis in Unmated Queen Honeybees (Apis mellifera capensis): Central Fusion and High Recombination Rates

PubMed Central

Oldroyd, Benjamin P.; Allsopp, Michael H.; Gloag, Rosalyn S.; Lim, Julianne; Jordan, Lyndon A.; Beekman, Madeleine

2008-01-01

The subspecies of honeybee indigenous to the Cape region of South Africa, Apis mellifera capensis, is unique because a high proportion of unmated workers can lay eggs that develop into females via thelytokous parthenogenesis involving central fusion of meiotic products. This ability allows pseudoclonal lineages of workers to establish, which are presently widespread as reproductive parasites within the honeybee populations of South Africa. Successful long-term propagation of a parthenogen requires the maintenance of heterozygosity at the sex locus, which in honeybees must be heterozygous for the expression of female traits. Thus, in successful lineages of parasitic workers, recombination events are reduced by an order of magnitude relative to meiosis in queens of other honeybee subspecies. Here we show that in unmated A. m. capensis queens treated to induce oviposition, no such reduction in recombination occurs, indicating that thelytoky and reduced recombination are not controlled by the same gene. Our virgin queens were able to lay both arrhenotokous male-producing haploid eggs and thelytokous female-producing diploid eggs at the same time, with evidence that they have some voluntary control over which kind of egg was laid. If so, they are able to influence the kind of second-division meiosis that occurs in their eggs post partum. PMID:18716331

The adaptive significance of hatching synchrony of waterfowl eggs

USGS Publications Warehouse

Flint, Paul L.; Lindberg, Mark S.; MacCluskie, Margaret C.; Sedinger, James S.

1994-01-01

We estimated the amount of incubation time that first laid Black Brent eggs received before completion of the clutch. First laid eggs received up to 48 hours of incubation before the last egg was laid in Brent clutches. Waterfowl clutches usually hatch within a period of 24 hours, suggesting that some mechanism reduces developmental asynchrony during incubation. The combination of incubation during laying and hatch synchronization mechanisms should be adaptive because these traits reduce nest exposure, maintain egg viability, and result in an earlier hatch date, all of which increase fitness in waterfowl.

Time-trends and congener profiles of PBDEs and PCBs in California peregrine falcons (Falco peregrinus).

PubMed

Park, June-Soo; Holden, Arthur; Chu, Vivian; Kim, Michele; Rhee, Alexandra; Patel, Puja; Shi, Yating; Linthicum, Janet; Walton, Brian J; McKeown, Karen; Jewell, Nicholas P; Hooper, Kim

2009-12-01

High levels (microg/g lw) of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were measured in peregrine falcon eggs from California (n = 90 eggs from 52 birds, 38 nest sites, collected 1986-2007, SigmaPBDEs median = 4.53, range = 0.08-53.1). Over the past 22 years, PBDE levels more than tripled each decade in the eggs, whereas PCB levels had no significant changes. PBDE levels were highest in eggs from major California cities ("Big Cities"), whereas PCBs showed no difference across the regions. For PBDEs, Big City eggs had markedly different patterns from Coastal eggs: BDE-209 and the higher brominated PBDEs (hexa-nona) were dominant congeners in Big City eggs, while BDE-47 and -99 were dominant in Coastal eggs. In many of the birds that gave multiple eggs over time ("time series"), PBDE patterns changed over time: the high proportions of BDE-209 and higher brominated PBDEs (short half-lives) in young birds contrasted with increasingly higher proportions of BDE-153 (long half-life) and other lower brominated PBDEs as the birds aged. These data are consistent with metabolic debromination of BDE-209 (t(1/2) = 1-2 weeks) to the lower brominated PBDEs, with accumulation over time of BDE-153 (t(1/2) = 3-4 years). In contrast, PCB patterns showed no differences by locations, and did not change over time. Diet (prey birds) may explain the urban PBDE pattern, as the patterns in urban pigeons and peregrines were similar, with high proportions of BDE-209 and the higher-brominated PBDEs. Also, our prey data (feathers from peregrine nests) showed urban peregrines having a higher proportion (>2 fold) of granivorous/opportunistic birds (e.g., "introduced feral" pigeons, mourning doves, starlings) in their diet than coastal peregrines. In summary, these data indicate that BDE-209 exits consumer products as an environmental contaminant to be taken up by wildlife (particularly in urban locations), and undergoes metabolic debromination to the banned lower-brominated PBDEs. High levels of the higher-brominated PBDE congeners, especially in urban locations, permitted accurate measures of relative proportions of homologues in each of the hexa-nona congener classes. Using the major hexa-nona homologues in each of these classes, we propose a pathway for the stepwise, metabolic debromination of BDE-209.

Increasing thiamine concentrations in lake trout eggs from Lakes Huron and Michigan coincide with low alewife abundance

USGS Publications Warehouse

Riley, Stephen C.; Rinchard, Jacques; Honeyfield, Dale C.; Evans, Allison N.; Begnoche, Linda

2011-01-01

Lake trout Salvelinus namaycush in the Laurentian Great Lakes suffer from thiamine deficiency as a result of adult lake trout consuming prey containing thiaminase, a thiamine-degrading enzyme. Sufficiently low egg thiamine concentrations result in direct mortality of or sublethal effects on newly hatched lake trout fry. To determine the prevalence and severity of low thiamine in lake trout eggs, we monitored thiamine concentrations in lake trout eggs from 15 sites in Lakes Huron and Michigan from 2001 to 2009. Lake trout egg thiamine concentrations at most sites in both lakes were initially low and increased over time at 11 of 15 sites, and the proportion of females with egg thiamine concentrations lower than the recommended management objective of 4 nmol/g decreased over time at eight sites. Egg thiamine concentrations at five of six sites in Lakes Huron and Michigan were significantly inversely related to site-specific estimates of mean abundance of alewives Alosa pseudoharengus, and successful natural reproduction of lake trout has been observed in Lake Huron since the alewife population crashed. These results support the hypothesis that low egg thiamine in Great Lakes lake trout is associated with increased alewife abundance and that low alewife abundance may currently be a prerequisite for successful reproduction by lake trout in the Great Lakes.

In Vitro Culturing and Live Imaging of Drosophila Egg Chambers: A History and Adaptable Method.

PubMed

Peters, Nathaniel C; Berg, Celeste A

2016-01-01

The development of the Drosophila egg chamber encompasses a myriad of diverse germline and somatic events, and as such, the egg chamber has become a widely used and influential developmental model. Advantages of this system include physical accessibility, genetic tractability, and amenability to microscopy and live culturing, the last of which is the focus of this chapter. To provide adequate context, we summarize the structure of the Drosophila ovary and egg chamber, the morphogenetic events of oogenesis, the history of egg-chamber live culturing, and many of the important discoveries that this culturing has afforded. Subsequently, we discuss various culturing methods that have facilitated analyses of different stages of egg-chamber development and different types of cells within the egg chamber, and we present an optimized protocol for live culturing Drosophila egg chambers.We designed this protocol for culturing late-stage Drosophila egg chambers and live imaging epithelial tube morphogenesis, but with appropriate modifications, it can be used to culture egg chambers of any stage. The protocol employs a liquid-permeable, weighted "blanket" to gently hold egg chambers against the coverslip in a glass-bottomed culture dish so the egg chambers can be imaged on an inverted microscope. This setup provides a more buffered, stable, culturing environment than previously published methods by using a larger volume of culture media, but the setup is also compatible with small volumes. This chapter should aid researchers in their efforts to culture and live-image Drosophila egg chambers, further augmenting the impressive power of this model system.

In vitro culturing and live imaging of Drosophila egg chambers: A history and adaptable method

PubMed Central

Peters, Nathaniel C.; Berg, Celeste A.

2017-01-01

Summary/Abstract The development of the Drosophila egg chamber encompasses a myriad of diverse germline and somatic events, and as such, the egg chamber has become a widely used and influential developmental model. Advantages of this system include physical accessibility, genetic tractability, and amenability to microscopy and live culturing, the last of which is the focus of this chapter. To provide adequate context, we summarize the structure of the Drosophila ovary and egg chamber, the morphogenetic events of oogenesis, the history of egg-chamber live culturing, and many of the important discoveries that this culturing has afforded. Subsequently, we discuss various culturing methods that have facilitated analyses of different stages of egg-chamber development and different types of cells within the egg chamber, and we present an optimized protocol for live culturing Drosophila egg chambers. We designed this protocol for culturing late-stage Drosophila egg chambers and live imaging epithelial tube morphogenesis, but with appropriate modifications it can be used to culture egg chambers of any stage. The protocol employs a liquid-permeable, weighted, “blanket” to gently hold egg chambers against the coverslip in a glass-bottomed culture dish so the egg chambers can be imaged on an inverted microscope. This setup provides a more buffered, stable culturing environment than previously published methods by using a larger volume of culture media, but the setup is also compatible with small volumes. This chapter should aid researchers in their efforts to culture and live image Drosophila egg chambers, further augmenting the impressive power of this model system. PMID:27557572

Effects of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in domestic pigeon squabs (Columba livia).

PubMed

Zhang, X Y; Li, L L; Miao, L P; Zhang, N N; Zou, X T

2018-01-01

This study was conducted to evaluate the effect of in ovo feeding of cationic amino acids on hatchability, hatch weights, and organ developments in pigeon squabs. Two experiments were conducted in this study. Eggs in Exp. 1 were subjected to modification of in ovo feeding in pigeons. Optimal time was determined by checking amniotic fluid volume, and suitable length was confirmed through ink injection. Results showed that the optimum time of in ovo feeding was on d 13 of embryonic development, and the suitable injected length was 20 mm to reach the amniotic cavity of the embryo. Eggs in Exp. 2 were transferred to access in ovo feeding of cationic amino acids. A total of 75 fertile pigeon eggs was randomly distributed into 5 treatments of 15 replicate eggs. Treatments in Exp. 2 consisted of non-injected controls (Control), a sterile buffered solution (0.75% saline), or a cationic amino acid mixture (> 98.5% purity crystalline L-arginine, > 98% purity crystalline L-lysine, and > 98.5% purity L-histidine) containing 0.1, 1, or 10% concentration (Conc.), which were relative to their total content in the eggs, respectively. The crystalline amino acids were dissolved in 200 μL buffered solution prior to in ovo feeding. After hatching, hatch weight (HW) and organ weight (OW) of the squabs were measured immediately. In ovo feeding of cationic amino acids increased the proportions of yolk-free hatch weight to hatch weight (YFHW/HW) (quadratic P = 0.01), and those of OW to YFHW including the heart (quadratic P = 0.01), kidney (quadratic P < 0.01), and liver (quadratic P = 0.02) compared to the control group, and the levels of those ratios were maximized in the 1% Conc group. Also, a proportion of small intestine weight to YFHW improved (linear P = 0.02, quadratic P = 0.05) after in ovo feeding. The organ weight of the head, leg, heart, lung, kidney, proventriculus, pancreas, liver, and small intestine correlated with YFHW positively (0.4 < correlation coefficient < 0.8, P < 0.05). In conclusion, cationic amino acids injection into amnion can improve the embryonic development, which may be mediated by the increment of relative organ weight. © 2017 Poultry Science Association Inc.

Egg collagen content is increased by a diet supplemented with wood charcoal powder containing wood vinegar liquid.

PubMed

Yamauchi, K; Matsumoto, Y; Yamauchi, K

2016-10-01

The aims of the present study were to examine whether collagen exists in egg, particularly in egg yolk; to establish a Fourier transform-near infrared (FT-NIR) measurement method for collagen in egg and to assess the possibility of increasing the collagen content by feeding hens a diet containing wood charcoal powder containing wood vinegar liquid (WCV). The collagen in eggs from 67-week-old hens fed on the dietary 0 and 9.9 g/kg WCV diets was investigated using a combination of histochemical, matrix-assisted laser desorption ionisation with time-of-flight mass spectrometry (MALDI-TOF MS), Fourier transform infrared (FT-IR) and FT-NIR approaches. All approaches used to identify collagen in egg yolk yielded positive results. The collagen in egg yolk measured using colorimetry, collagen in egg yolk, egg white and eggshell membrane using FT-NIR and collagen in egg yolk determined by treating the egg yolk with collagenase were abundant after feeding a dietary WCV (p<0.05). These results suggest that egg yolk contains collagen, that the collagen in egg can be measured using FT-NIR, and that the collagen content of egg yolk can be increased by feeding dietary WCV diets.

Comparative embryology of five species of lampreys of the upper Great Lakes

USGS Publications Warehouse

Smith, Allen J.; Howell, John H.; Piavis, George W.

1968-01-01

The four species of lampreys native to the upper Great Lakes (American brook lamprey, Lampetra lamotteni; chestnut lamprey, Ichthyomyzon castaneus; northern brook lamprey, I. fossor; and silver lamprey, I. unicuspis) were collected in various stages of their life cycle and maintained in the laboratory until sexually mature. Secondary sex characters of the four native species are compared. Several batches of eggs of each species were reared at 18.4A?C and their development was compared to that of the exotic sea lamprey, Petromyzon marinus. The temperature of 18.4A?C was previously determined to be optimum for development of the sea lamprey. The high percentage survival of many batches of eggs of native species to prolarvae indicated that 18.4A?C was near the optimum for them. Survival to the burrowing stage varied considerably among different batches of eggs from the same species; some batches failed to produce prolarvae. The staging characteristics used for the sea lamprey were applicable to the native species, except for the end point of the burrowing stage. Embryos of the native species in each stage of development appeared according to the time sequence established for the sea lamprey.

9 CFR 592.510 - Base time rate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Base time rate. 592.510 Section 592.510 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION VOLUNTARY INSPECTION OF EGG PRODUCTS Fees and Charges § 592.510 Base time rate. The...

CrazyEgg Reports for Single Page Analysis

EPA Pesticide Factsheets

CrazyEgg provides an in depth look at visitor behavior on one page. While you can use GA to do trend analysis of your web area, CrazyEgg helps diagnose the design of a single Web page by visually displaying all visitor clicks during a specified time.

Transovarial persistence of Babesia ovata DNA in a hard tick, Haemaphysalis longicornis, in a semi-artificial mouse skin membrane feeding system.

PubMed

Umemiya-Shirafuji, Rika; Hatta, Takeshi; Okubo, Kazuhiro; Sato, Moeko; Maeda, Hiroki; Kume, Aiko; Yokoyama, Naoaki; Igarashi, Ikuo; Tsuji, Naotoshi; Fujisaki, Kozo; Inoue, Noboru; Suzuki, Hiroshi

2017-12-20

Bovine piroplasmosis, a tick-borne protozoan disease, is a major concern for the cattle industry worldwide due to its negative effects on livestock productivity. Toward the development of novel therapeutic and vaccine approaches, tick-parasite experimental models have been established to clarify the development of parasites in the ticks and the transmission of the parasites by ticks. A novel tick-Babesia experimental infection model recently revealed the time course of Babesia ovata migration in its vector Haemaphysalis longicornis, which is a dominant tick species in Japan. However, there has been no research on the transovarial persistence of B. ovata DNA using this experimental infection model. Here we assessed the presence of B. ovata DNA in eggs derived from parthenogenetic H. longicornis female ticks that had engorged after semi-artificial mouse skin membrane feeding of B. ovata-infected bovine red blood cells. The oviposition period of the engorged female ticks was 21-24 days in the semi-artificial feeding. Total egg weight measured daily reached a peak by day 3 in all female ticks. Nested PCR revealed that 3 of 10 female ticks laid B. ovata DNA-positive eggs after the semi-artificial feeding. In addition, B. ovata DNA was detected at the peak of egg weight during oviposition, indicating that B. ovata exist in the eggs laid a few days after the onset of oviposition in the tick. These findings will contribute to the establishment of B. ovata-infected H. longicornis colonies under laboratory conditions.

Economic and market issues on the sustainability of egg production in the United States: analysis of alternative production systems.

PubMed

Sumner, D A; Gow, H; Hayes, D; Matthews, W; Norwood, B; Rosen-Molina, J T; Thurman, W

2011-01-01

Conventional cage housing for laying hens evolved as a cost-effective egg production system. Complying with mandated hen housing alternatives would raise marginal production costs and require sizable capital investment. California data indicate that shifts from conventional cages to barn housing would likely cause farm-level cost increases of about 40% per dozen. The US data on production costs of such alternatives as furnished cages are not readily available and European data are not applicable to the US industry structure. Economic analysis relies on key facts about production and marketing of conventional and noncage eggs. Even if mandated by government or buyers, shifts to alternative housing would likely occur with lead times of at least 5 yr. Therefore, egg producers and input suppliers would have considerable time to plan new systems and build new facilities. Relatively few US consumers now pay the high retail premiums required for nonconventional eggs from hens housed in alternative systems. However, data from consumer experiments indicate that additional consumers would also be willing to pay some premium. Nonetheless, current data do not allow easy extrapolation to understand the willingness to pay for such eggs by the vast majority of conventional egg consumers. Egg consumption in the United States tends to be relatively unresponsive to price changes, such that sustained farm price increases of 40% would likely reduce consumption by less than 10%. This combination of facts and relationships suggests that, unless low-cost imports grew rapidly, requirements for higher cost hen housing systems would raise US egg prices considerably while reducing egg consumption marginally. Eggs are a low-cost source of animal protein and low-income consumers would be hardest hit. However, because egg expenditures are a very small share of the consumer budget, real income loss for consumers would be small in percentage terms. Finally, the high egg prices imposed by alternative hen housing systems raise complex issues about linking public policy costs to policy beneficiaries.

Effects of calcium and magnesium hardness on the fertilization and hatching success of hybrid catfish eggs

USDA-ARS?s Scientific Manuscript database

Hybrid catfish are exclusively produced by strip spawning of channel catfish females, fertilizing stripped eggs with blue catfish sperm, and hatching the fertilized eggs. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on ...

Spatial variations in mortality in pelagic early life stages of a marine fish (Gadus morhua)

NASA Astrophysics Data System (ADS)

Langangen, Øystein; Stige, Leif C.; Yaragina, Natalia A.; Ottersen, Geir; Vikebø, Frode B.; Stenseth, Nils Chr.

2014-09-01

Mortality of pelagic eggs and larvae of marine fish is often assumed to be constant both in space and time due to lacking information. This may, however, be a gross oversimplification, as early life stages are likely to experience large variations in mortality both in time and space. In this paper we develop a method for estimating the spatial variability in mortality of eggs and larvae. The method relies on survey data and physical-biological particle-drift models to predict the drift of ichthyoplankton. Furthermore, the method was used to estimate the spatially resolved mortality field in the egg and larval stages of Barents Sea cod (Gadus morhua). We analyzed data from the Barents Sea for the period between 1959 and 1993 when there are two surveys available: a spring and a summer survey. An individual-based physical-biological particle-drift model, tailored to the egg and larval stages of Barents Sea cod, was used to predict the drift trajectories from the observed stage-specific distributions in spring to the time of observation in the summer, a drift time of approximately 45 days. We interpreted the spatial patterns in the differences between the predicted and observed abundance distributions in summer as reflecting the spatial patterns in mortality over the drift period. Using the estimated mortality fields, we show that the spatial variations in mortality might have a significant impact on survival to later life stages and we suggest that there may be trade-offs between increased early survival in off shore regions and reduced probability of ending up in the favorable nursing grounds in the Barents Sea. In addition, we show that accounting for the estimated mortality field, improves the correlation between a simulated recruitment index and observation-based indices of juvenile abundance.

Effects of ovarian steroids and prolactin on the sequential development of nesting behaviour in female budgerigars.

PubMed

Hutchison, R E

1975-10-01

As intact, breeding female budgerigars approach egg-laying, they spend an increasing amount of time in the nestbox and nest hollow. The brood patch area begins to defeather and becomes vascular and the oviduct increases in weight. Precursory albumen forms in the tubular glands of the oviduct. Oestradiol (OB) treatment in combination with prolactin (OB+PL) induced ovariectomized budgerigars to display nesting behaviour which did not differ from that shown by intact females in the 3 days immediately preceding egg-laying. In contrast, OB induced only the initial phase of the nesting sequence and the effects of OB in combination with progesterone (OB+PR) were intermediate between treatments with OB alone and OB+PL. Incubation of artificial eggs occurred only in the OB+PL group and the latency to display of the incubation posture was shorter in the OB+PL group than in the OB+PR group. No incubation posture was displayed by the OB-treated group. Oviduct development was not influenced by prolactin, but progesterone induced precocious development of tubular glands in the magnum region of the oviduct. Treatment with OB+PR induced uniform development of precursor albumen in the tubular glands. Development of the brood patch occurred with both OB+PL and OB+PR treatment. However, OB+PR resulted in defeathering which was advanced in relation to vascularity when compared with intact breeding females, whereas defeathering and vascularity of the OB+PL group did not differ from that of intact females at egg-laying. These results indicate that prolactin in combination with oestradiol was more effective than progesterone not only in inducing the later phases of nesting behaviour but also in initiating incubation behaviour and defeathering of the brood patch area.

Molecular characterization, expression profile of the FSHRgene and its association with egg production traits in muscovy duck.

PubMed

Xu, Jiguo; Gao, Xinfeng; Li, Xing; Ye, Qiao; Jebessa, Endashaw; Abdalla, Bahareldin Ali; Nie, Qinghua

2017-06-01

Follicle-stimulating hormone (FSH) and its receptor play a key role in the follicular development and regulation of steroidogenesis in the ovary and spermatogenesis in the testis. The purpose of this study was to characterize themuscovy duck FSHR gene, identify SNPs and their association with egg production traits in muscovy ducks. Here, we cloned the complementary DNA (cDNA) sequence of FSHR, and examined the expression patterns of FSHR gene in adult female muscovy duck tissues. The cloned cDNA of the muscovy duck FSHR gene shared high similarity to those of pekin duck (Anas platyrhynchos) (95.7%) and chicken (93.2%). Three different muscovy duck FSHR transcripts were identified. Quantitative real-time PCR (RT-qPCR) results showed that the FSHR gene was expressed in all the 14 tested tissues, and the highest expression level was seen in the ovary. A total of 16 SNPs were identified, among which, four SNPs were located in the coding region of FSHR. The SNP C320T is significantly associated with egg production at 59 weeks of age (P < 0.05), whereas the SNP A227G is significantly associated with age at first egg stage (P < 0.05). These results suggest that the two SNPs (A227G and C320T) of FSHR gene are associated with egg production traits and could be potential markers that can be used for marker-assisted selection programmes to increase egg production in muscovy duck.

A Laboratory Investigation of the Suspension, Transport, and Settling of Silver Carp Eggs Using Synthetic Surrogates

PubMed Central

Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

2015-01-01

Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study provide insights about transport, suspension, and dispersion of silver carp eggs. The knowledge gained from this study is useful to characterize the critical hydrodynamic conditions of the flow at which surrogates for silver carp water-hardened eggs settle out of suspension, and provides insight into how eggs may interact with riverbed sediments and morphology. PMID:26713855

A laboratory investigation of the suspension, transport, and settling of silver carp eggs using synthetic surrogates

USGS Publications Warehouse

Garcia, Tatiana; Zuniga Zamalloa, Carlo; Jackson, P. Ryan; Murphy, Elizabeth A.; Garcia, Marcelo H.

2015-01-01

Asian carp eggs are semi-buoyant and must remain suspended in the water to survive, supported by the turbulence of the flow, until they hatch and develop the ability to swim. Analysis of the transport and dispersal patterns of Asian carp eggs will facilitate the development and implementation of control strategies to target the early life stages. Experimenting with Asian carp eggs is complicated due to practical issues of obtaining eggs in close proximity to experimental facilities and extensive handling of eggs tends to damage them. Herein, we describe laboratory experiments using styrene beads (4.85 mm diameter) as synthetic surrogate eggs to mimic the physical properties of water-hardened silver carp eggs. The first set of experiments was completed in a rectangular vertical column filled with salt water. The salinity of the water was adjusted in an iterative fashion to obtain a close approximation of the fall velocity of the styrene beads to the mean fall velocity of silver carp water-hardened eggs. The terminal fall velocity of synthetic eggs was measured using an image processing method. The second set of experiments was performed in a temperature-controlled recirculatory flume with a sediment bed. The flume was filled with salt water, and synthetic eggs were allowed to drift under different flow conditions. Drifting behavior, suspension conditions, and settling characteristics of synthetic eggs were observed. At high velocities, eggs were suspended and distributed through the water column. Eggs that touched the sediment bed were re-entrained by the flow. Eggs saltated when they touched the bed, especially at moderate velocities and with a relatively flat bed. At lower velocities, some settling of the eggs was observed. With lower velocities and a flat bed, eggs were trapped near the walls of the flume. When bedforms were present, eggs were trapped in the lee of the bedforms in addition to being trapped near the flume walls. Results of this research study provide insights about transport, suspension, and dispersion of silver carp eggs. The knowledge gained from this study is useful to characterize the critical hydrodynamic conditions of the flow at which surrogates for silver carp water-hardened eggs settle out of suspension, and provides insight into how eggs may interact with riverbed sediments and morphology.

[Conception rate and embryo development in guinea pigs with synchronized estrus induced by progesterone implant].

PubMed

Ueda, H; Kosaka, T; Takahashi, K W

1994-01-01

Observations were made on the timing of mating and the pre-implantation development of fertilized eggs in guinea pigs synchronized by long-term progesterone treatment. Females received a subcutaneous implant of progesterone-filled silastic tubing for 14 days. Copulation was observed from the evening of day 4 to the morning of day 6 in 53 of 54 females (98%). Most of them (47/53, 89%) copulated on day 5 after removal of the tubing. Designating the day of copulation (day 5 after removal of the tubing) as day 0 of gestation, embryos collected from the genital tract were at the 4-cell, 8-cell, morula, and blastocyst stages on days 1, 3, 4 and 5 of gestation, respectively. Eggs were recovered at high incidence (85-100%) from days 1 to 5 of gestation. On day 6 gestation, no eggs were recovered from the genital tract, suggesting that implantation had occurred. The mean litter size (+/- S. D.) was 4.0 +/- 0.8 pups, which were born normally after a mean gestation period of 67 +/- 1 days in 7 synchronized females. Since the female guinea pigs synchronized by the long-term progesterone treatment had normal reproductive ability similar to that of cyclic females, this technique would make it possible to obtain animals at a scheduled time even in smaller-sized colonies. In addition, observations on the pre-implantation development of embryos in females with synchronized estrus might be a useful aid in the field of reproductive research.

High atmospheric temperatures and ‘ambient incubation’ drive embryonic development and lead to earlier hatching in a passerine bird

PubMed Central

Griffith, Simon C.; Mainwaring, Mark C.; Sorato, Enrico; Beckmann, Christa

2016-01-01

Tropical and subtropical species typically experience relatively high atmospheric temperatures during reproduction, and are subject to climate-related challenges that are largely unexplored, relative to more extensive work conducted in temperate regions. We studied the effects of high atmospheric and nest temperatures during reproduction in the zebra finch. We characterized the temperature within nests in a subtropical population of this species in relation to atmospheric temperature. Temperatures within nests frequently exceeded the level at which embryo’s develop optimally, even in the absence of parental incubation. We experimentally manipulated internal nest temperature to demonstrate that an average difference of 6°C in the nest temperature during the laying period reduced hatching time by an average of 3% of the total incubation time, owing to ‘ambient incubation’. Given the avian constraint of laying a single egg per day, the first eggs of a clutch are subject to prolonged effects of nest temperature relative to later laid eggs, potentially increasing hatching asynchrony. While birds may ameliorate the negative effects of ambient incubation on embryonic development by varying the location and design of their nests, high atmospheric temperatures are likely to constitute an important selective force on avian reproductive behaviour and physiology in subtropical and tropical regions, particularly in the light of predicted climate change that in many areas is leading to a higher frequency of hot days during the periods when birds breed. PMID:26998315

Food-cooking processes modulate allergenic properties of hen's egg white proteins.

PubMed

Liu, Xiaoyu; Feng, Bai-Sui; Kong, Xiaoli; Xu, Hong; Li, Xiumin; Yang, Ping-Chang; Liu, Zhigang

2013-01-01

Reducing the allergenicity of food allergens can suppress the clinical symptoms of food allergy. The objective of the present study was to investigate the effects of processing on the allergenic properties of hen's egg white proteins. Eggs were processed by traditional Chinese cooking, including steaming, water boiling, frying, spicing and tea boiling. The contents of processed egg protein were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis; the allergenicity was evaluated by Western blotting, enzyme-linked immunosorbent assay and enzyme allergosorbent test inhibition. Circular dichroism spectrum analysis of four major egg allergens from various egg products was performed as well. A mouse model of food allergy was developed to test the allergenicity of processed egg protein in vivo. Protein degradation was significant following tea boiling and spiced-tea boiling. The total allergenic potential of water-boiled egg and fried egg was relatively higher than that of steamed egg, spiced egg and tea-boiled egg. Challenge with proteins from raw egg, water-boiled egg and fried egg induced skewed T-helper 2 pattern responses (Th2 responses) in the intestine of mice sensitized to egg proteins; however, when the mice sensitized to egg proteins were challenged with proteins from steamed egg, spiced egg and tea-boiled egg, respectively, only weak Th2 responses were induced in their intestine. Processing by steaming, spicing, or tea boiling can weaken the allergenicity of egg proteins. Copyright © 2012 S. Karger AG, Basel.

Effects of fine sediment, hyporheic flow, and spawning site characteristics on survival and development of bull trout embryos

USGS Publications Warehouse

Bowerman, Tracy; Neilson, Bethany; Budy, Phaedra

2014-01-01

Successful spawning is imperative for the persistence of salmonid populations, but relatively little research has been conducted to evaluate factors affecting early life-stage survival for bull trout (Salvelinus confluentus), a threatened char. We conducted a field experiment to assess the relationship between site-specific environmental factors and bull trout embryo survival and fry emergence timing. Survival from egg to hatch was negatively related to percent fine sediment (<1 mm) in the redd and positively related to the strength of downwelling at spawning sites. Survival of eggs to fry emergence was also negatively related to fine sediment, and the best statistical models included additional variables that described the rate of downwelling and intragravel flow within the incubation environment. Fry emerged at an earlier stage in development from redds with high percentages of fine sediment. Increased hydraulic conductivity via redd construction and selection of spawning sites with strong downwelling appear to enhance hyporheic flow rates and bull trout egg survival, but early life-stage success may ultimately be limited by intrusion of fine sediment into the incubation environment.

Density-Dependent Oviposition by Female Aedes albopictus (Diptera: Culicidae) Spreads Eggs Among Containers During the Summer but Accumulates Them in the Fall.

PubMed

Fonseca, D M; Kaplan, L R; Heiry, R A; Strickman, D

2015-07-01

When possible, oviparous females should deposit eggs in sites that maximize the future performance of their offspring. Therefore, studies of oviposition behavior may uncover parameters important to offspring fitness. Gravid female Aedes albopictus (Skuse) were given a choice of containers with leaf infusion or plain water, either open or with a cover with a small opening, and their behavior was compared under summer (long day, higher temperature) or fall (short day, lower temperature) regimes. Open containers with leaf infusion were always preferred, but over time, summer females expanded their choices to oviposit in all containers and follow-up experiments indicated that the number of eggs laid was inversely correlated to the number of eggs present. In contrast, fall females laying diapausing eggs that do not hatch until the spring, accumulated eggs in open containers with food resulting in high egg densities. Combined, these results demonstrate a seasonal shift that suggests either high winter egg mortality or safety in numbers. It also demonstrates that female Ae. albopictus change their behavior based on cues associated with expected added risk, which varies across time and space. The wide distribution of summer eggs across container types may contribute to the fast expansion of Ae. albopictus across its invasive range, but egg accumulation in the fall may be exploited for control. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Investigation of a type C/D botulism outbreak in free-range laying hens in France.

PubMed

Souillard, R; Le Maréchal, C; Ballan, V; Rouxel, S; Léon, D; Balaine, L; Poëzevara, T; Houard, E; Robineau, B; Robinault, C; Chemaly, M; Le Bouquin, S

2017-04-01

In 2014, a botulism outbreak in a flock of laying hens was investigated in France. In the flock of 5020 hens, clinical signs of botulism occurred at 46 weeks of age. A type C/D botulism outbreak was confirmed using the mouse lethality assay for detection of botulinum toxin in serum and a real-time PCR test to detect Clostridium botulinum in intestinal contents. The disease lasted one week with a mortality rate of 2.6% without recurrence. Botulism in laying hens has rarely been reported. Five monthly visits were made to the farm between December 2014 and May 2015 for a longitudinal study of the persistence of C. botulinum in the poultry house after the outbreak, and to assess egg contamination by C. botulinum. Several samples were collected on each visit: in the house (from the ventilation circuit, the egg circuit, water and feed, droppings) and the surrounding area. Thirty clean and 30 dirty eggs were also swabbed at each visit. In addition, 12 dirty and 12 clean eggs were collected to analyse eggshell and egg content. The samples were analysed using real-time PCR to detect type C/D C. botulinum. The bacterium was still detected in the house more than 5 months after the outbreak, mostly on the walls and in the egg circuit. Regarding egg contamination, the bacteria were detected only on the shell but not in the content of the eggs. Control measures should therefore be implemented throughout the egg production period to avoid dissemination of the bacteria, particularly during egg collection.

Oviposition and the plasma concentrations of LH, progesterone, and corticosterone in bobwhite quail (Colinus virginianus) fed parathion

USGS Publications Warehouse

Rattner, B.A.; Sileo, L.; Scanes, C.G.

1982-01-01

Bobwhite quail were fed concentrations of parathion (0,50, 100, 200 or 400 p.p.m.) for 10 days. Food intake, body weight change, brain acetylcholinesterase activity, egg production, and ovary weight were reduced in a dose-dependent manner. In a second experiment, birds were fed 0, 25 or 100 p.p.m. parathion or pair-fed control food to equate consumption in the 100 p.p.m. group. Egg production was not affected in birds fed 25 p.p.m. or in the pair-fed group, but the daily time of oviposition was more variable than in the control group. Cessation of egg production, inhibition of follicular development, and reduced plasma LH concentration were observed in birds fed 100 p.p.m. parathion. These findings indicate that exposure to parathion can impair reproduction, possibly by altering gonadotrophin secretion.

Time trends and patterns of reported egg consumption in the U.S. by sociodemographic characteristics

USDA-ARS?s Scientific Manuscript database

Eggs have the potential to contribute essential nutrients to nutritionally vulnerable populations on limited food budgets. Further research is needed to better understand patterns of egg consumption across diverse sociodemographic groups in order to inform clinical practice and industry decision-mak...

Chick Development and Asynchroneous Hatching in the Zebra Finch (Taeniopygia guttata castanotis).

PubMed

Ikebuchi, Maki; Okanoya, Kazuo; Hasegawa, Toshikazu; Bischof, Hans-Joachim

2017-10-01

The mode of hatching in birds has important impacts on both parents and chicks, including the costs and risks of breeding for parents, and sibling competition in a clutch. Birds with multiple eggs in a single clutch often begin incubating when most eggs are laid, thereby reducing time of incubation, nursing burden, and sibling competition. In some songbirds and some other species, however, incubation starts immediately after the first egg is laid, and the chicks thus hatch asynchronously. This may result in differences in parental care and in sibling competition based on body size differences among older and younger chicks, which in turn might produce asynchronous development among siblings favoring the first hatchling, and further affect the development and fitness of the chicks after fledging. To determine whether such processes in fact occur in the zebra finch, we observed chick development in 18 clutches of zebra finches. We found that there were effects of asynchronous hatching, but these were smaller than expected and mostly not significant. Our observations suggest that the amount of care given to each chick may be equated with such factors as a camouflage effect of the down feathers, and that the low illumination within the nest also complicates the determination of the hatching order by the parents.

Ecdysteroids in the adults and eggs of Opogona sacchari (Bojer), an invasive alien pest.

PubMed

Wang, FangHai; Zhang, GuRen; Wen, RuiZhen; He, GuoFeng

2008-02-01

In order to understand the composition and quantitative variation of ecdysteroids in the adults and eggs of Opogona sacchari (Bojer), an invasive alien pest, we analyzed the ecdysteroid composition and titers in the adult and egg of this pest. On day 4 after eclosion, the titer of ecdysteroids in the male adult was 0.080 ng/adult, much lower than 5.978 ng/adult in the female adult. During the development of ovaries, the titer of ecdysteroids was low on the first two days, and high in the late period, with the peak (10.48 ng/ovary) appearing on day 3. During the development of eggs, the titer of ecdysteroids was about 0.010 ng/egg from day 1 to day 3, and then decreased to 0.006 ng/egg on day 4. In both adults and eggs, three main components of ecdysteroids were found by identification of HPLC/RIA. They were 20-hydroxyecdysone, 26-hydroxyecdysone, and an unidentified component.

Effects of temperature on development, mortality, mating and blood feeding behavior of Culiseta incidens (Diptera: Culicidae).

PubMed

Su, T; Mulla, M S

2001-06-01

Culiseta incidens Thomson is distributed over most of the western USA and Canada northward to Alaska. Because this mosquito is difficult to colonize, its biology has not been well investigated. We colonized this species in 1998 and studied the effects of temperature on various aspects of its life cycle. The time required for egg melanization and the duration of the egg stage were negatively correlated with temperature. The proportion of fertile egg rafts was temperature-independent. An inverse relationship existed between temperature and egg hatch. Molting and stadium duration after hatching were temperature-dependent, with higher temperature accelerating development and molting. Larvae and pupae experienced lower mortality and higher molting success at lower temperatures. Survivorship of adult mosquitoes fed on sugar solution was inversely proportional to temperature, lethal times for 50% mortality (LT50) were greater at the lower temperature than at the higher temperature. Females survived longer than did males at all test temperatures. Because this species is eurygamous, mating only occurred in large cages. Mating success was also affected by temperature. At the test temperatures, 20 degrees C, 25 degrees C and 30 degrees C, mating started from 3-5 days after emergence and reached a peak on days 13-15 after emergence. Maximum mating rates at 20 degrees C and 25 degrees C were higher than at 30 degrees C. Blood feeding, as indicated by cumulative feeding rates, was affected by cage size, mosquito age and temperature. Mosquitoes in large cages exhibited a much higher feeding rate than in small cages. With age, the cumulative blood feeding rate increased, with the highest rate at 25 degrees C, followed by 20 degrees C and 30 degrees C. At all temperatures tested, most of the blood fed females were mated.

The effects of temperature, diet, and other factors on development, survivorship, and oviposition of Aethina tumida (Coleoptera: Nitidulidae).

PubMed

Meikle, William G; Patt, Joseph M

2011-06-01

Developmental rate and survivorship of small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae), life stages were measured across different temperatures (21, 25, 28, 32 and 35 degrees C) and diets, which included natural and artificial pollen, honey, and bee pupae. Temperature affected hatch success, time to hatching, and larval growth. Eggs hatched in 61 h at 21 degrees C but in < 22 h at 35 degrees C. Larvae achieved peak weight in < 8 d at 35 degrees C but needed 17 d at 21 degrees C. Diet had comparatively little effect on larval survivorship or maximum weight, although larvae fed only bee pupae had lower survivorship. Access to soil influenced pupation success. Duration of the life stage spent in the soil, during which pupation occurs, was also affected by temperature: adults emerged after 32.7 d at 21 degrees C but after only 14.8 d at 35 degrees C, albeit with high mortality. Minimum temperature for development was estimated at 13.5 degrees C for eggs, and 10.0 degrees C for larvae and pupae. Temperature influenced adult longevity and oviposition: on a honey and pollen diet average adult lifespan was 92.8 d at 24 degrees C but only 11.6 d at 35 degrees C. Beetles lived longer at 28 degrees C or lower but produced the most eggs per female, regardless of diet, at 32 degrees C. Beetle density influenced fecundity: beetles kept at three pairs per vial laid 6.7 times more eggs per female than those kept as single pairs. Overall, beetles fared best at 28-32 degrees C with mortality of all stages highest at 35 degrees C.

Salmonella Typhimurium and Salmonella Sofia: Growth in and Persistence on Eggs under Production and Retail Conditions

PubMed Central

McAuley, Catherine M.; Duffy, Lesley L.; Subasinghe, Nela; Hogg, Geoff; Coventry, John; Fegan, Narelle

2015-01-01

Salmonellosis in Australia has been linked to eggs and egg products with specific serotypes associated with outbreaks. We compared attachment to and survival on egg shells and growth in eggs of two Salmonella serotypes, an egg outbreak associated Salmonella Typhimurium and a non-egg-associated Salmonella enterica ssp. II 1,4,12,27:b:[e,n,x] (S. Sofia). Experiments were conducted at combinations of 4, 15, 22, 37 and 42°C. No significant differences occurred between the serotypes in maximum growth rates, which were significantly greater (P < 0.001) in egg yolk (0.427 log10 CFU/mL/h) compared to whole egg (0.312 log10 CFU/mL/h) and egg white (0.029 log10 CFU/mL/h). Attachment to egg shells varied by time (1 or 20 min) and temperature (4, 22 and 42°C), with S. Typhimurium isolates attaching at higher levels (P < 0.05) than S. Sofia after 1 min at 4°C and S. Typhimurium ATCC 14028 attaching at higher (P < 0.05) levels at 22°C. Survival on egg shells was not significantly different across isolates. Salmonella serotypes behaved similarly regarding growth in egg contents, attachment to egg shells and survival on eggs, indicating that other factors more likely contributed to reasons for S. Typhimurium being implicated in multiple egg-associated outbreaks. PMID:26539536

Streambed scour of salmon spawning habitat in a regulated river influenced by management of peak discharge

USGS Publications Warehouse

Gendaszek, Andrew S.; Burton, Karl D.; Magirl, Christopher S.; Konrad, Christopher P.

2017-01-01

In the Pacific Northwest of the United States, salmon eggs incubating within streambed gravels are susceptible to scour during floods. The threat to egg-to-fry survival by streambed scour is mitigated, in part, by the adaptation of salmon to bury their eggs below the typical depth of scour. In regulated rivers globally, we suggest that water managers consider the effect of dam operations on scour and its impacts on species dependent on benthic habitats.We instrumented salmon-spawning habitat with accelerometer scour monitors (ASMs) at 73 locations in 11 reaches of the Cedar River in western Washington State of the United States from Autumn 2013 through the Spring of 2014. The timing of scour was related to the discharge measured at a nearby gage and compared to previously published ASM data at 26 locations in two reaches of the Cedar River collected between Autumn 2010 and Spring 2011.Thirteen percent of the recovered ASMs recorded scour during a peak-discharge event in March 2014 (2-to 3-year recurrence interval) compared to 71% of the recovered ASMs during a higher peak-discharge event in January 2011 (10-year recurrence interval). Of the 23 locations where ASMs recorded scour during the 2011 and 2014 deployments, 35% had scour when the discharge was ≤87.3 m3/s (3,082 ft3/s) (2-year recurrence interval discharge) with 13% recording scour at or below the 62.3 m3/s (2,200 ft3/s) operational threshold for peak-discharge management during the incubation of salmon eggs.Scour to the depth of salmon egg pockets was limited during peak discharges with frequent (1.25-year or less) recurrence intervals, which managers can regulate through dam operations on the Cedar River. Pairing novel measurements of the timing of streambed scour with discharge data allows the development of peak-discharge management strategies that protect salmon eggs incubating within streambed gravels during floods.

Spatial and temporal trends of contaminants in eggs of wading birds from San Francisco Bay, California

USGS Publications Warehouse

Hothem, R.L.; Roster, D.L.; King, K.A.; Keldsen, T.J.; Marois, Katherine C.; Wainwright, S.E.

1995-01-01

Between 1989 and 1991, reproduction by black-crowned night-herons (Nycticorax nycticorax) and snowy egrets (Egretta thula) was studied at sites in San Francisco Bay. Eggs were collected from these and other bay sites and from South Wilbur Flood Area, a reference site in California's San Joaquin Valley. Eggs were analyzed for inorganic trace elements, organochlorine pesticides, and polychlorinated biphenyls (PCBs). Results were compared among sites and years and with results of previous studies. There was some evidence of impaired reproduction, but concentrations of contaminants were generally lower than threshold levels for such effects. Egg hatchability was generally good, with predation being the factor that most limited reproductive success. Mean PCB concentrations were generally higher in eggs from the south end of San Francisco Bay than from the north, but the only temporal change, an increase, was observed at Alcatraz Island. There were spatial differences for p,p'-DDE in night-heron eggs in 1990, but the highest mean concentration of DDE was in night-heron eggs from South Wilbur in 1991. Temporal declines in maximum concentrations of DDE in eggs were observed in the bay, but means did not change significantly over time, At Bair Island in the southern end of the bay, mean concentrations of mercury decreased while selenium increased in night-heron eggs over time, but there were no clear bay-wide spatial or temporal trends for either element.

Effects of egg shell quality and washing on Salmonella Infantis penetration.

PubMed

Samiullah; Chousalkar, K K; Roberts, J R; Sexton, M; May, D; Kiermeier, A

2013-07-15

The vast majority of eggs in Australia are washed prior to packing to remove dirt and fecal material and to reduce the microbial contamination of the egg shell. The egg contents can be an ideal growth medium for microorganisms which can result in human illness if eggs are stored improperly and eaten raw or undercooked, and it is estimated that egg-related salmonellosis is costing Australia $44 million per year. Egg shell characteristics such as shell thickness, amount of cuticle present, and thickness of individual egg shell layers can affect the ease with which bacteria can penetrate the egg shell and washing could partially or completely remove the cuticle layer. The current study was conducted to investigate the effects of egg washing on cuticle cover and effects of egg shell quality and cuticle cover on Salmonella Infantis penetration of the egg shell. A higher incidence of unfavorable ultrastructural variables of the mammillary layer such as late fusion, type B bodies, type A bodies, poor cap quality, alignment, depression, erosion and cubics were recorded in Salmonella penetrated areas of egg shells. The influence of egg washing on the ability of Salmonella Infantis on the egg shell surface to enter the egg internal contents was also investigated using culture-based agar egg penetration and real-time qPCR based experiments. The results from the current study indicate that washing affected cuticle cover. There were no significant differences in Salmonella Infantis penetration of washed or unwashed eggs. Egg shell translucency may have effects on Salmonella Infantis penetration of the egg shell. The qPCR assay was more sensitive for detection of Salmonella Infantis from egg shell wash and internal contents than traditional microbiological methods. The agar egg and whole egg inoculation experiments indicated that Salmonella Infantis penetrated the egg shells. Egg washing not only can be highly effective at removing Salmonella Infantis from the egg shell surface, but also allows subsequent trans-shell and trans-membrane penetration into the egg. Consequently, it is important to prevent recontamination of the egg after washing. Copyright © 2013 Elsevier B.V. All rights reserved.

Rigid shells enhance survival of gekkotan eggs.

PubMed

Andrews, Robin M

2015-11-01

The majority of lizards and snakes produce permeable parchment-shelled eggs that require high moisture conditions for successful embryonic development. One clade of gekkotan lizards is an exception; females produce relatively impermeable rigid-shelled eggs that normally incubate successfully under low moisture conditions. I tested the hypothesis that the rigid-shell increases egg survival during incubation, but only under low moisture conditions. To test this hypothesis, I incubated rigid-shelled eggs of Chondrodactylus turneri under low and under high moisture conditions. Eggs were incubated with parchment-shelled eggs of Eublepharis macularius to insure that incubation conditions were suitable for parchment-shelled eggs. Chondrodactylus turneri eggs had very high survival (>90%) when they were incubated under low moisture conditions. In contrast, eggs incubated under high moisture conditions had low survival overall, and lower survival than those of the parchment-shelled eggs of E. macularius. Mortality of C. turneri and E. macularius eggs incubated under high moisture conditions was the result of fungal infection, a common source of egg mortality for squamates under laboratory and field conditions. These observations document high survival of rigid-shelled eggs under low moisture conditions because eggs escape from fungal infection. Highly mineralized rigid shells also make egg survival independent of moisture availability and may also provide protection from small invertebrates in nature. Enhanced egg survival could thus compensate for the low reproductive output of gekkotans that produce rigid-shelled eggs. © 2015 Wiley Periodicals, Inc.

Effects of triploidy induction on antioxidant defense status in rainbow trout (Oncorhynchus mykiss) during early development.

PubMed

Taghipoor, Kaveh; Keyvanshokooh, Saeed; Salati, Amir Parviz; Pasha-Zanoosi, Hossein; Babaheydari, Samad Bahrami

2016-08-01

The objective of the present study was to examine the antioxidant status of rainbow trout (Oncorhynchus mykiss) during the early stages of development (fertilized egg, eyed egg, alevin and fry) as an effect of triploidy induction. Eggs and milt were taken from eight females and six males. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat-shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group (control and heat-shocked) and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. Triplicate samples of fertilized eggs from each experimental group were randomly selected 1.5h post-fertilization and at the eyed egg stage of development (18 days post-fertilization, dpf). At 27 dpf, triplicate samples of alevins were chosen from each group. Based on ploidy determination experiment performed on both groups, nine diploid and nine triploid fry (76 dpf) were also selected. The triploidy induction success rate was 87.1%. Vitamin C was in lesser concentrations in fertilized eggs and eyed eggs of the heat-shock treatment group as compared with eggs of the diploid group. Alevins of the heat-shock treatment group had a lower superoxide dismutase (SOD) activity than alevins of the diploid group. Glutathione peroxidase (GPx) level was greater in fertilized eggs and alevins of the heat-shock treatment group as compared to diploids. Catalse (CAT) activity was greater in fertilized eggs, alevins and fry of the heat-shock treatment group than those of the diploid group. Malondialdehyde (MDA), as an index of lipid peroxidation, was in greater concentration in fertilized eggs of the group that was heat-shocked, but it was lesser in alevins and fry of the group in which the eggs were heat-shocked as compared to diploid counterparts. The results demonstrate that heat-shock treatment leads to changes in the values of antioxidant enzymes such as SOD, CAT and GPx, and low molecular weight free-radical scavengers such as vitamin C, as well as level of lipid peroxidation. Copyright © 2016 Elsevier B.V. All rights reserved.

Eggs: The role of gravity in the establishment of the dorso-ventral axis in the amphibian embryo (7-IML-1)

NASA Technical Reports Server (NTRS)

Ubbels, Geertje A.

1992-01-01

The purpose of this experiment is to fertilize frog (Xenopus laevis) eggs under microgravity, to perform histological fixations at two different programmed times, and after return to Earth, to determine whether timing and pattern of egg cleavages and axis formation are normal. Because of the limited viability of the gametes, this experiment will be the very first to be activated in the Biorack. Various aspects of this investigation are discussed.

Nondestructive pasteurization of shell eggs using radio frequency energy

USDA-ARS?s Scientific Manuscript database

Shell eggs are on the top of the list of the 10 riskiest foods regulated by the Food and Drug Administration and 352 outbreaks from 1990 to 2006 were linked to eggs. The goals of this study were to design and assemble an apparatus to apply RF energy to shell eggs and to develop a process for pasteur...

Examining the relationships between egg cortisol and oxidative stress in developing wild sockeye salmon (Oncorhynchus nerka).

PubMed

Taylor, Jessica J; Sopinka, Natalie M; Wilson, Samantha M; Hinch, Scott G; Patterson, David A; Cooke, Steven J; Willmore, William G

2016-10-01

Maternally-derived hormones in oocytes, such as glucocorticoids (GCs), play a crucial role in embryo development in oviparous taxa. In fishes, maternal stressor exposure increases circulating and egg cortisol levels, the primary GC in fishes, as well as induces oxidative stress. Elevated egg cortisol levels modify offspring traits but whether maternal oxidative stress correlates with circulating and egg cortisol levels, and whether maternal/egg cortisol levels correlate with offspring oxidative stress have yet to be determined. The objective of this study was to examine the relationships among maternal and egg cortisol, and maternal and offspring oxidative stress to provide insight into the potential intergenerational effects of stressor exposure in sockeye salmon (Oncorhynchus nerka). Antioxidant concentration and oxidative stress were measured in maternal tissues (plasma, brain, heart and liver) as well as offspring developmental stages (pre-fertilization, 24h post-fertilization, eyed, and hatch), and were compared to both naturally-occurring and experimentally-elevated (via cortisol egg bath) levels of cortisol in eggs. Oxygen radical absorptive capacity of tissues from maternal sockeye salmon was measured spectrophotometrically and was not correlated with maternal or egg cortisol concentrations. Also, naturally-occurring and experimentally-elevated cortisol levels in eggs (to mimic maternal stress) did not affect oxidative stress or antioxidant capacity of the offspring. We conclude that the metrics of maternal stress examined in sockeye salmon (i.e., maternal/egg cortisol, maternal oxidative stress) are independent of each other, and that egg cortisol content does not influence offspring oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

No nutritional benefits of egg cannibalism for Coleomegilla maculata (Coleoptera: Coccinellidae) on a high-quality diet.

PubMed

Abdelwahab, A H; Michaud, J P; Bayoumy, M H; Awadalla, S S; El-Gendy, M

2017-09-11

Egg cannibalism serves various functions in the Coccinellidae. Here we examined the fitness consequences of egg cannibalism by neonates, fourth instar larvae, and prereproductive adults of Coleomegilla maculata DeGeer, with beetles fed a diet of Ephestia kuehniella Zeller eggs. Cannibalism of two eggs by neonates had no effect on development, and cannibalism of five eggs by fourth instars did not benefit any aspect of reproduction, but delayed pupation slightly. Cannibalism of eggs by pre-reproductive adults had no effect on reproductive success in any combination of reciprocal crosses of cannibals and non-cannibals. Females did not recognize, nor avoid consuming, their own clutches, and cannibalism propensity did not change following mating and onset of oviposition in either sex. These results contrast with those for more strictly aphidophagous species in which larvae gain developmental benefits, and females may recognize and avoid filial egg clusters while using cannibalism to interfere with conspecific females, whereas males reduce egg cannibalism after mating because they cannot recognize filial clusters. Egg cannibalism may confer developmental benefits to C. maculata when diet is suboptimal, as previously shown, but no such benefits were evident on the high-quality E. kuehniella egg diet. Female C. maculata do not require aphids to reproduce and distribute their eggs broadly in the environment, given that larvae can develop on pollen and non-aphid prey. Thus, C. maculata is not subject to the intraspecific competition that selects for cannibalism in more aphidophagous species, and also lacks many secondary adaptations associated with the behaviour.

Regulator of G-protein signaling 2 (RGS2) suppresses premature calcium release in mouse eggs

PubMed Central

Bernhardt, Miranda L.; Lowther, Katie M.; Padilla-Banks, Elizabeth; McDonough, Caitlin E.; Lee, Katherine N.; Evsikov, Alexei V.; Uliasz, Tracy F.; Chidiac, Peter; Williams, Carmen J.; Mehlmann, Lisa M.

2015-01-01

During oocyte maturation, capacity and sensitivity of Ca2+ signaling machinery increases dramatically, preparing the metaphase II (MII)-arrested egg for fertilization. Upon sperm-egg fusion, Ca2+ release from IP3-sensitive endoplasmic reticulum stores results in cytoplasmic Ca2+ oscillations that drive egg activation and initiate early embryo development. Premature Ca2+ release can cause parthenogenetic activation prior to fertilization; thus, preventing inappropriate Ca2+ signaling is crucial for ensuring robust MII arrest. Here, we show that regulator of G-protein signaling 2 (RGS2) suppresses Ca2+ release in MII eggs. Rgs2 mRNA was recruited for translation during oocyte maturation, resulting in ∼20-fold more RGS2 protein in MII eggs than in fully grown immature oocytes. Rgs2-siRNA-injected oocytes matured to MII; however, they had increased sensitivity to low pH and acetylcholine (ACh), which caused inappropriate Ca2+ release and premature egg activation. When matured in vitro, RGS2-depleted eggs underwent spontaneous Ca2+ increases that were sufficient to cause premature zona pellucida conversion. Rgs2−/− females had reduced litter sizes, and their eggs had increased sensitivity to low pH and ACh. Rgs2−/− eggs also underwent premature zona pellucida conversion in vivo. These findings indicate that RGS2 functions as a brake to suppress premature Ca2+ release in eggs that are poised on the brink of development. PMID:26160904

Calcium and actin in the saga of awakening oocytes.

PubMed

Santella, Luigia; Limatola, Nunzia; Chun, Jong T

2015-04-24

The interaction of the spermatozoon with the egg at fertilization remains one of the most fascinating mysteries of life. Much of our scientific knowledge on fertilization comes from studies on sea urchin and starfish, which provide plenty of gametes. Large and transparent, these eggs have served as excellent model systems for studying egg activation and embryo development in seawater, a plain natural medium. Starfish oocytes allow the study of the cortical, cytoplasmic and nuclear changes during the meiotic maturation process, which can also be triggered in vitro by hormonal stimulation. These morphological and biochemical changes ensure successful fertilization of the eggs at the first metaphase. On the other hand, sea urchin eggs are fertilized after the completion of meiosis, and are particularly suitable for the study of sperm-egg interaction, early events of egg activation, and embryonic development, as a large number of mature eggs can be fertilized synchronously. Starfish and sea urchin eggs undergo abrupt changes in the cytoskeleton and ion fluxes in response to the fertilizing spermatozoon. The plasma membrane and cortex of an egg thus represent "excitable media" that quickly respond to the stimulus with the Ca(2+) swings and structural changes. In this article, we review some of the key findings on the rapid dynamic rearrangements of the actin cytoskeleton in the oocyte/egg cortex upon hormonal or sperm stimulation and their roles in the modulation of the Ca(2+) signals and in the control of monospermic fertilization. Copyright © 2015 Elsevier Inc. All rights reserved.

The Oral Provocation Test for Raw Egg in Patients with Hen Egg Allergy.

PubMed

Kido, Jun; Nishi, Natsuko; Matsumoto, Tomoaki

2018-06-06

Many researchers have made efforts to develop diagnostic tools for predicting the outcome of oral food challenges (OFCs). The aim of this study was to assess the diagnostic value of the skin prick test (SPT) and blood-specific IgE concentrations based on the outcome of the OFCs for heated and raw hen egg. This study included 103 children with suspected hen egg allergy (HEA; median age 23 months, range 10-155; 72 boys, 31 girls). Forty-three patients were diagnosed with HEA by OFC. Of 60 patients who tolerated heated egg white (HEW), 22 underwent the OFC for raw hen egg and 7 developed adverse reactions after ingesting raw egg. Their wheal diameters and specific IgE levels for egg white and ovomucoid were determined. Wheal diameters as well as blood-specific IgE levels for egg white and ovomucoid were significantly larger in children with positive OFC results for HEW than in those with negative results. However, there were no significant differences between the positive and negative test results for raw hen egg white (REW) in wheal diameter or blood-specific IgE levels. The SPT and blood-specific IgE can be used to diagnose HEA. However, the provocation test for REW in children without HEW allergy is important because the values of SPT and specific IgE were not significantly different between children with and without raw egg allergy. © 2018 S. Karger AG, Basel.

9 CFR 590.522 - Breaking room operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... room personnel shall wash their hands thoroughly with odorless soap and water each time they enter the... wholesomeness by smelling the shell or the egg meat and by visual examination at the time of breaking. All egg... of shell particles and other foreign material shall be cleaned and sanitized each time it is...

9 CFR 590.522 - Breaking room operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... room personnel shall wash their hands thoroughly with odorless soap and water each time they enter the... wholesomeness by smelling the shell or the egg meat and by visual examination at the time of breaking. All egg... of shell particles and other foreign material shall be cleaned and sanitized each time it is...

9 CFR 590.522 - Breaking room operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... room personnel shall wash their hands thoroughly with odorless soap and water each time they enter the... wholesomeness by smelling the shell or the egg meat and by visual examination at the time of breaking. All egg... of shell particles and other foreign material shall be cleaned and sanitized each time it is...

Verification of Egg Farming Systems from The Netherlands and New Zealand Using Stable Isotopes.

PubMed

Rogers, Karyne M; van Ruth, Saskia; Alewijn, Martin; Philips, Andy; Rogers, Pam

2015-09-30

Stable isotopes were used to develop authentication criteria of eggs laid under cage, barn, free range, and organic farming regimens from The Netherlands and New Zealand. A training set of commercial poultry feeds and egg albumen from 49 poultry farms across The Netherlands was used to determine the isotopic variability of organic and conventional feeds and to assess trophic effects of these corresponding feeds and barn, free range, and organic farming regimens on corresponding egg albumen. A further 52 brands of New Zealand eggs were sampled from supermarket shelves in 2008 (18), 2010 (30), and 2014 (4) to characterize and monitor changes in caged, barn, free range, and organic egg farming regimens. Stable carbon (δ(13)C) and nitrogen (δ(15)N) isotopes of 49 commercial poultry feeds and their corresponding egg albumens reveals that Dutch poultry are fed exclusively on a plant-based feed and that it is possible to discriminate between conventional and organic egg farming regimens in The Netherlands. Similarly, it is possible to discriminate between New Zealand organic and conventional egg farming regimens, although in the initial screening in 2008, results showed that some organic eggs had isotope values similar to those of conventional eggs, suggesting hens were not exclusively receiving an organic diet. Dutch and New Zealand egg regimens were shown to have a low isotopic correlation between both countries, because of different poultry feed compositions. In New Zealand, both conventional and organic egg whites have higher δ(15)N values than corresponding Dutch egg whites, due to the use of fishmeal or meat and bone meal (MBM), which is banned in European countries. This study suggests that stable isotopes (specifically nitrogen) show particular promise as a screening and authentication tool for organically farmed eggs. Criteria to assess truthfulness in labeling of organic eggs were developed, and we propose that Dutch organic egg whites should have a minimum δ(15)N value of 4.8‰ to account for an organic plant derived diet. Monitoring of New Zealand egg isotopes over the past 7 years suggests that organic eggs should have a minimum δ(15)N value of 6.0‰, and eggs falling below this value should be investigated further by certification authorities.

A new species of Trichosomoididae (Nematoda) from skin of red snapper, Lutjanus campechanus (Perciformes: Lutjanidae), on the Texas-Louisiana shelf, northern Gulf of Mexico.

PubMed

Ruiz, Carlos F; Ray, Candis L; Cook, Melissa; Grace, Mark A; Bullard, Stephen A

2013-04-01

Eggs and larvae of Huffmanela oleumimica n. sp. infect red snapper, Lutjanus campechanus (Poey, 1860), were collected from the Texas-Louisiana Shelf (28°16'36.58″N, 93°03'51.08″W) and are herein described using light and scanning electron microscopy. Eggs in skin comprised fields (1-5 × 1-12 mm; 250 eggs/mm(2)) of variously oriented eggs deposited in dense patches or in scribble-like tracks. Eggs had clear (larvae indistinct, principally vitelline material), amber (developing larvae present) or brown (fully developed larvae present; little, or no, vitelline material) shells and measured 46-54 μm (x = 50; SD ± 1.6; n = 213) long, 23-33 (27 ± 1.4; 213) wide, 2-3 (3 ± 0.5; 213) in eggshell thickness, 18-25 (21 ± 1.1; 213) in vitelline mass width, and 36-42 (39 ± 1.1; 213) in vitelline mass length with protruding polar plugs 5-9 (7 ± 0.6; 213) long and 5-8 (6 ± 0.5; 213) wide. Fully developed larvae were 160-201 (176 ± 7.9) long and 7-8 (7 ± 0.5) wide, had transverse cuticular ridges, and were emerging from some eggs within and beneath epidermis. The new species differs from its congeners by having eggs <65 μm in total length and that have a brown eggshell when fully developed, an envelope throughout development, and irregularly-dispersed eggshell spines plus a larva >110 μm long with transverse cuticular ridges. The eggs lack a spindle-shaped envelope, polar filaments, and eggshell ridges. This is the first report of a species of Huffmanela from a snapper (Lutjanidae) or from the Gulf of Mexico. A table of egg and larval characteristics, hosts, and localities for Huffmanela spp. is provided.

Process of egg formation in the female body cavity and fertilization in male eggs of Phytoseiulus persimilis (Acari: Phytoseiidae).

PubMed

Toyoshima, S; Nakamura, M; Nagahama, Y; Amano, H

2000-01-01

The process of egg formation in the body cavity of a phytoseiid mite, Phytoseiulus persimilis, was observed to examine fertilization of male eggs. After insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. Two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. After the egg became filled with yolk granules the two pronuclei fused. The egg moved via the narrow entrance at the ventral region into the oviduct, where the eggshell was formed. When the eggshell was complete, and while embryogenesis proceeded, the egg was deposited. In the meantime some ova began to expand sequentially and two joining pronuclei appeared in expanding eggs. The joining pronuclei in the first egg proved male diploidy. This is additional evidence of pseudo-arrhenotoky in this phytoseiid mite species, since the first eggs developed into males.

Yolk proteins during ovary and egg development of mature female freshwater crayfish (Cherax quadricarinatus).

PubMed

Serrano-Pinto, Vania; Vazquez-Boucard, Celia; Villarreal-Colmenares, Humberto

2003-01-01

Vitellins from ovaries and eggs at different stages of development in freshwater crayfish (Cherax quadricarinatus) were examined by chromatography, PAGE and SDS-PAGE. With these methods, two forms of vitellin (Vt1 and Vt2) were observed in ovaries and eggs (stages I and V). In ovaries in secondary vitellogenesis, native molecular mass was 470 (Vt1) and 440 (Vt2) kDa. The electrophoretic pattern of the eggs proved to be more complex. The protein molecular mass depend on the development stage of the egg: stage I, 650 kDa (Vt1) and 440 kDa (Vt2); stage V, 390 kDa (Vt1) and 340 kDa (Vt2). The identified vitellins appear to be lipo-glycocarotenoprotein. A similar vitellin polypeptide composition was observed in the two forms of vitellin from ovaries and eggs in stage V. In ovaries the SDS-PAGE analysis showed four subunits with molecular weights of approximately 180, 120, 95 and 80 kDa (Vt1 and Vt2). The polypeptide composition in the two forms of vitellins in stage I and stage III eggs were different at 195, 190, 130 and 110 kDa (Vt1) and 116 and 107 kDa (Vt2). On the other hand, in stage V eggs, 110, 95, 87 and 75 kDa (Vt1 and Vt2) were identified. Two antibodies (Ab1 and Ab2) were prepared against the purified proteins of stage V eggs and their specificity was demonstrated by radial immunoprecipitation, and Western blotting analysis. Two forms of vitellins were also found in stage V eggs after chromatography on Sepharose CL-2B column and hydroxylapatite and polyacrylamide gel electrophoresis.

Cell cycle in egg cell and its progression during zygotic development in rice.

PubMed

Sukawa, Yumiko; Okamoto, Takashi

2018-03-01

Rice egg is arrested at G1 phase probably by OsKRP2. After fusion with sperm, karyogamy, OsWEE1-mediated parental DNA integrity in zygote nucleus, zygote progresses cell cycle to produce two-celled embryo. In angiosperms, female and male gametes exist in gametophytes after the complementation of meiosis and the progression of nuclear/cell division of the haploid cell. Within the embryo sac, the egg cell is specially differentiated for fertilization and subsequent embryogenesis, and cellular programs for embryonic development, such as restarting the cell cycle and de novo gene expression, are halted. There is only limited knowledge about how the cell cycle in egg cells restarts toward zygotic division, although the conversion of the cell cycle from a quiescent and arrested state to an active state is the most evident transition of cell status from egg cell to zygote. This is partly due to the difficulty in direct access and analysis of egg cells, zygotes and early embryos, which are deeply embedded in ovaries. In this study, precise relative DNA amounts in the nuclei of egg cells, developing zygotes and cells of early embryos were measured, and the cell cycle of a rice egg cell was estimated as the G1 phase with a 1C DNA level. In addition, increases in DNA content in zygote nuclei via karyogamy and DNA replication were also detectable according to progression of the cell cycle. In addition, expression profiles for cell cycle-related genes in egg cells and zygotes were also addressed, and it was suggested that OsKRP2 and OsWEE1 function in the inhibition of cell cycle progression in egg cells and in checkpoint of parental DNA integrity in zygote nucleus, respectively.

Effects of Schistosoma haematobium infection on reproductive success and male outcrossing ability in the simultaneous hermaphrodite, Bulinus truncatus (Gastropoda: Planorbidae).

PubMed

Schrag, S J; Rollinson, D

1994-01-01

The schistosome intermediate snail host, Bulinus truncatus (Mollusca: Planorbidae), has two reproductive (phally) morphs. Both aphallics and euphallics can self-fertilize, but aphallics cannot donate sperm because they do not develop a functional penis and prostate. This study investigated the interactions between phally and fitness consequences of Schistosoma haematobium infection in B. truncatus. Snails which developed patent infections produced 26% fewer eggs than controls and 35% fewer eggs than exposed snails which did not develop infections. This reduction was due to a lower lifetime production of egg masses and a smaller mean number of eggs/mass in infected snails relative to control or exposed snails. However, there was no evidence of increased mortality in infected snails. Contrary to reports of fecundity compensation in other intermediate host snails, egg production post-exposure during the pre-patent period did not increase relative to that of controls in either infected or exposed snails. Phally did not influence susceptibility to infection or length of the prepatent period. Furthermore, lifetime egg, egg mass and hatchling production, as well as mean eggs/mass and number of hatchlings reaching maturity, did not differ significantly between aphallics and euphallics within control of exposed experimental groups. However, within the infected group euphallics produced 38% fewer eggs, smaller egg masses, and fewer hatchlings reaching maturity than aphallics, supporting the prediction of a cost to the growth and maintenance of a full male tract. This cost was detectable only when snails were under the stress of infection. The proportion of euphallic offspring produced did not differ across experimental groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Nesting ecology of roseate spoonbills at Nueces Bay, Texas

USGS Publications Warehouse

White, D.H.; Mitchell, C.A.

1982-01-01

We conducted a 3-year study in 1978-80 of thenesting ecology of Roseate Spoonbills (Ajaia ajaja) at Nueces Bay, Texas. Reproductive success, as well as nesting chronology, nest composition and placement, growth and development of young, egg measurements, and pollutant residues in eggs were determined. For 154 marked nests, the average clutch size was 3.0 eggs; 73% of the eggs hatched, and 87% of the nests were successful (fledged at least one young). Nest success (total fledglings: total eggs) averaged 50% during the study, or 1.5 fledglings per nest. Incubation began the day after the first egg was laid, and the incubation period for each egg was 22 days. Eggs hatched in the order that they were laid; the first and second egg hatched on consecutive days, and the second, third, and fourth egg hatched every other day. Nest composition and size were highly consistent, as was distance between nests within clusters, but nest placement varied considerably and was dependent on the vegetative configuration of the dredged-material islands. Growth rate of nestlings conformed to a 'standard' growth curve where body weight equaled that of adults at fledging. There was no difference in weight gain among siblings based on actual age. Nestlings fledged at about siz weeks of age when feather development was complete. At fledging, the bills of juveniles had almost reached adult width, but bill length was only 67% that of adults.

Egg freezing and egg banking: empowerment and alienation in assisted reproduction.

PubMed

Robertson, John A

2014-06-01

With the development of rapid freezing of human oocytes, many programs have reported IVF success rates comparable to those achieved with fresh eggs and thawed frozen embryos. Egg freezing is now gaining professional and regulatory acceptance as a safe and effective technique for women who wish to avoid discarding excess embryos, who face fertility-threatening medical treatments, or who want to preserve their eggs for use when they are better situated to have a family. This article focuses on the uses of and justification for egg freezing, the path to professional acceptance, the variability in success rates, and the controversy over freezing eggs for social rather than medical reasons. It also addresses the emergence of egg banking as a separate sector in the infertility industry, the regulatory issues that it poses, and its effect on egg donation. Key here is the legal control of stored eggs by banking women and their options when they wish to dispose of those eggs. The analysis is framed around empowerment and alienation. Egg freezing is generally empowering for women, but the donation or sale of unused eggs to infertile women, egg bankers, and researchers also raises issues of alienation.

Egg freezing and egg banking: empowerment and alienation in assisted reproduction

PubMed Central

Robertson, John A.

2014-01-01

With the development of rapid freezing of human oocytes, many programs have reported IVF success rates comparable to those achieved with fresh eggs and thawed frozen embryos. Egg freezing is now gaining professional and regulatory acceptance as a safe and effective technique for women who wish to avoid discarding excess embryos, who face fertility-threatening medical treatments, or who want to preserve their eggs for use when they are better situated to have a family. This article focuses on the uses of and justification for egg freezing, the path to professional acceptance, the variability in success rates, and the controversy over freezing eggs for social rather than medical reasons. It also addresses the emergence of egg banking as a separate sector in the infertility industry, the regulatory issues that it poses, and its effect on egg donation. Key here is the legal control of stored eggs by banking women and their options when they wish to dispose of those eggs. The analysis is framed around empowerment and alienation. Egg freezing is generally empowering for women, but the donation or sale of unused eggs to infertile women, egg bankers, and researchers also raises issues of alienation. PMID:27774158

Spawning habitat selection of hickory shad

USGS Publications Warehouse

Harris, Julianne E.; Hightower, J.E.

2011-01-01

We examined the spawning habitat selectivity of hickory shad Alosa mediocris, an anadromous species on the Atlantic coast of North America. Using plankton tows and artificial substrates (spawning pads), we collected hickory shad eggs in the Roanoke River, North Carolina, to identify spawning timing, temperature, and microhabitat use. Hickory shad eggs were collected by both sampling gears in March and April. The results from this and three other studies in North Carolina indicate that spawning peaks at water temperatures between 12.0??C and 14.9??C and that approximately 90% occurs between 11.0??C and 18.9??C. Hickory shad eggs were collected in run and riffle habitats. Water velocity and substrate were significantly different at spawning pads with eggs than at those without eggs, suggesting that these are important microhabitat factors for spawning. Hickory shad eggs were usually collected in velocities of at least 0.1 m/s and on all substrates except those dominated by silt. Eggs were most abundant on gravel, cobble, and boulder substrates. Hickory shad spawned further upstream in years when water discharge rates at Roanoke Rapids were approximately average during March and April (2005 and 2007), as compared with a severe drought year (2006), suggesting that water flows may affect not only spawning site selection but also the quantity and quality of spawning habitat available at a macrohabitat scale. Using our field data and a Bayesian approach to resource selection analysis, we developed a preliminary habitat suitability model for hickory shad. This Bayesian approach provides an objective framework for updating the model as future studies of hickory shad spawning habitat are conducted. ?? American Fisheries Society 2011.

Temperature-Dependent Development and Survival of Brazilian Populations of the Mediterranean Fruit Fly, Ceratitis capitata, from Tropical, Subtropical and Temperate Regions

PubMed Central

Ricalde, Marcelo P.; Nava, Dori E.; Loeck, Alci E.; Donatti, Michele G.

2012-01-01

The Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is one of the principal exotic pests affecting Brazilian production in the northeastern and southeastern regions of Brazil. In the south, it is has potential as a serious threat to temperate-climate fruit farms, since it is already found in urban and suburban communities in this region. We studied the biological characteristics of C. capitata populations from Pelotas-RS (temperate climate), Petrolina-PE (tropical), and Campinas-SP (subtropical). Ceratitis capitata biology was studied under controlled temperature (15, 20, 25, 30, and 35 ± 1 °C), 70 ± 10% RH, and 14:10 L:D photoperiod. The duration and survival rate of the egg, larval, and pupal stages were evaluated and the thermal requirements of these three populations were determined. The duration and survival of these developmental stages varied with temperature, with similar values for the three populations, except for some variation in the egg phase. Egg to adult developmental time for all three populations was inversely proportional to temperature; from 15 to 30 °C developmental time varied from 71.2 to 17.1, 70.2 to 17.1, and 68.5 to 16.9 days, respectively. Survival during development was affected at 15 to 30 °C, and differed significantly from survival at 20 to 25 °C. At 35 °C, immature stages did not develop. The basal temperature and degree-day requirement were similar for all immature stages except for the egg stage. The basal temperatures and thermal constants were 9.30 and 350, 8.47 and 341, and 9.60 °C and 328 degree-days for the Pelotas, Petrolina, and Campinas populations, respectively. Results suggested that survival and thermal requirements are similar for these tropical, subtropical, and temperate populations of C. capitata, and demonstrate the species' capacity to adapt to different climate conditions. PMID:22963468

Temperature sequence of eggs from oviposition through distribution: processing--part 2.

PubMed

Koelkebeck, K W; Patterson, P H; Anderson, K E; Darre, M J; Carey, J B; Ahn, D U; Ernst, R A; Kuney, D R; Jones, D

2008-06-01

The Egg Safety Action Plan released in 1999 raised questions concerning egg temperature used in the risk assessment model. Therefore, a national study was initiated to determine the internal and external temperature sequence of eggs from oviposition through distribution. Researchers gathered data from commercial egg production, shell egg processing, and distribution facilities. The experimental design was a mixed model with 2 random effects for season and geographic region and a fixed effect for operation type (inline or offline). For this report, internal and external egg temperature data were recorded at specific points during shell egg processing in the winter and summer months. In addition, internal egg temperatures were recorded in pre- and postshell egg processing cooler areas. There was a significant season x geographic region interaction (P < 0.05) for both surface and internal temperatures. Egg temperatures were lower in the winter vs. summer, but eggs gained in temperature from the accumulator to the postshell egg processing cooler. During shell egg processing, summer egg surface and internal temperatures were greater (P < 0.05) than during the winter. When examining the effect of shell egg processing time and conditions, it was found that 2.4 and 3.8 degrees C were added to egg surface temperatures, and 3.3 and 6.0 degrees C were added to internal temperatures in the summer and winter, respectively. Internal egg temperatures were higher (P < 0.05) in the preshell egg processing cooler area during the summer vs. winter, and internal egg temperatures were higher (P < 0.05) in the summer when eggs were (3/4) cool (temperature change required to meet USDA-Agricultural Marketing Service storage regulation of 7.2 degrees C) in the postshell egg processing area. However, the cooling rate was not different (P > 0.05) for eggs in the postshell egg processing cooler area in the summer vs. winter. Therefore, these data suggest that season of year and geographic location can affect the temperature of eggs during shell egg processing and should be a component in future assessments of egg safety.

Effect of Cold Storage on Biological Traits of Psix saccharicola (Hymenoptera: Platygastridae), an Egg Parasitoid of Acrosternum arabicum (Hemiptera: Pentatomidae).

PubMed

Forouzan, Farzane; Jalali, Mohammad Amin; Ziaaddini, Mahdi; Hashemi Rad, Hamid

2018-05-28

Psix saccharicola (Mani) (Hymenoptera: Platygastridae) is a solitary egg parasitoid of the pistachio green stink bug, Acrosternum arabicum (Wagner) (Hemiptera: Pentatomidae), which is one of the most important pests of pistachio in Iran. Augmentation of P. saccharicola field populations using mass-reared individuals may provide an alternative to conventional pesticide use for pistachio green stink bug control. Cold storage is an important component of mass-rearing protocols for optimum timing of host egg parasitization and potentially extended storage of P. saccharicola pupae prior to adult emergence. The impact of cold storage on A. arabicum eggs for various time intervals at 4.0°C was investigated. Results indicated that host eggs stored at 4.0°C for up to 60 d could be exploited by P. sacchricola, whereas no offspring were produced when eggs were stored for 120 d. The emergence rates of the F1 and F2 generations declined with increased host egg storage time. Both sex ratio and survival rate of the F2 generation decreased as the refrigeration time of host eggs increased. The impact of cold storage on P. saccharicola pupae was evaluated. Reared pupae of P. saccharicola were held for 1 wk at three temperatures and compared with a control (27 ± 1°C). Psix saccharicola pupae were tolerant to cold storage at 8 and 12°C. Cold storage adversely affected mean adult emergence at 4°C, which decreased following low temperature exposure. Furthermore, mean percentage survivorship was unaffected by storage at low temperatures in the F1 generation, but was reduced at 4°C. The sex ratio of the F1 generation became more male-biased when held at lower storage temperatures. The highest female proportion was observed at 12°C.

Timing of Allergenic Food Introduction to the Infant Diet and Risk of Allergic or Autoimmune Disease: A Systematic Review and Meta-analysis.

PubMed

Ierodiakonou, Despo; Garcia-Larsen, Vanessa; Logan, Andrew; Groome, Annabel; Cunha, Sergio; Chivinge, Jennifer; Robinson, Zoe; Geoghegan, Natalie; Jarrold, Katharine; Reeves, Tim; Tagiyeva-Milne, Nara; Nurmatov, Ulugbek; Trivella, Marialena; Leonardi-Bee, Jo; Boyle, Robert J

2016-09-20

Timing of introduction of allergenic foods to the infant diet may influence the risk of allergic or autoimmune disease, but the evidence for this has not been comprehensively synthesized. To systematically review and meta-analyze evidence that timing of allergenic food introduction during infancy influences risk of allergic or autoimmune disease. MEDLINE, EMBASE, Web of Science, CENTRAL, and LILACS databases were searched between January 1946 and March 2016. Intervention trials and observational studies that evaluated timing of allergenic food introduction during the first year of life and reported allergic or autoimmune disease or allergic sensitization were included. Data were extracted in duplicate and synthesized for meta-analysis using generic inverse variance or Mantel-Haenszel methods with a random-effects model. GRADE was used to assess the certainty of evidence. Wheeze, eczema, allergic rhinitis, food allergy, allergic sensitization, type 1 diabetes mellitus, celiac disease, inflammatory bowel disease, autoimmune thyroid disease, and juvenile rheumatoid arthritis. Of 16 289 original titles screened, data were extracted from 204 titles reporting 146 studies. There was moderate-certainty evidence from 5 trials (1915 participants) that early egg introduction at 4 to 6 months was associated with reduced egg allergy (risk ratio [RR], 0.56; 95% CI, 0.36-0.87; I2 = 36%; P = .009). Absolute risk reduction for a population with 5.4% incidence of egg allergy was 24 cases (95% CI, 7-35 cases) per 1000 population. There was moderate-certainty evidence from 2 trials (1550 participants) that early peanut introduction at 4 to 11 months was associated with reduced peanut allergy (RR, 0.29; 95% CI, 0.11-0.74; I2 = 66%; P = .009). Absolute risk reduction for a population with 2.5% incidence of peanut allergy was 18 cases (95% CI, 6-22 cases) per 1000 population. Certainty of evidence was downgraded because of imprecision of effect estimates and indirectness of the populations and interventions studied. Timing of egg or peanut introduction was not associated with risk of allergy to other foods. There was low- to very low-certainty evidence that early fish introduction was associated with reduced allergic sensitization and rhinitis. There was high-certainty evidence that timing of gluten introduction was not associated with celiac disease risk, and timing of allergenic food introduction was not associated with other outcomes. In this systematic review, early egg or peanut introduction to the infant diet was associated with lower risk of developing egg or peanut allergy. These findings must be considered in the context of limitations in the primary studies.

The impact of six insecticides commonly used in control of agricultural pests on the generalist predator Hippodamia convergens (Coleoptera: Coccinellidae).

PubMed

Santos, Kenia Fernanda Aguiar; Zanuzo Zanardi, Odimar; de Morais, Matheus Rovere; Jacob, Cynthia Renata Oliveira; de Oliveira, Monique Bárbara; Yamamoto, Pedro Takao

2017-11-01

Hippodamia convergens is an important predator found in different agroecosystems. We evaluated the impacts of six insecticides on eggs, larvae and adults of this predator. For eggs, all insecticides reduced larval hatching rates, but did not affect egg duration. Chlorpyrifos and phosmet reduced larval survival; and chlorpyrifos, etofenprox and phosmet prolonged the larva development time. The survival and duration of pupae were not affected by all insecticides tested. Chlorpyrifos reduced fecundity, fertility and longevity when eggs were sprayed. For first-instar larvae, chlorpyrifos, etofenprox, phosmet and imidacloprid caused 100% mortality, while azadirachtin and thiamethoxam caused 35.0 and 52.7% mortality, respectively. However, azadirachtin and thiamethoxam did not affect the other biological parameters of the predator. In adults, chlorpyrifos, etofenprox and phosmet reduced adult survival. Chlorpyrifos, etofenprox, and phosmet reduced fecundity and longevity, but did not affect fertility. Azadirachtin, imidacloprid and thiamethoxam did not affect fecundity, fertility or longevity. Based on demographic parameters, all insecticides reduced the net reproductive rate (R o ), intrinsic rate of increase (r) and finite rate of increase (λ) of the predator when eggs were treated directly. Azadirachtin, chlorpyrifos, etofenprox and phosmet increased the mean generation time (T), while the effects of imidacloprid and thiamethoxam were similar to the control. When first-instar larvae were treated, azadirachtin and thiamethoxam reduced the R o , r and λ. Thiamethoxam increased the T value, while the effects of the other insecticides were similar to the control. These insecticides should be used with caution, in order to reduce their harmful effects on the predator in agroecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Distribution and elimination of Norfloxacin in Fenneropenaeus chinensis larvae

NASA Astrophysics Data System (ADS)

Sun, Ming; Li, Jian; Zhao, Fazhen; Li, Jitao; Chang, Zhiqiang

2013-09-01

This study examined the distribution and elimination of Norfloxacin (NFLX) in Fenneropenaeus chinensis ovary and egg and newly hatched larvae. Mature parental shrimp were exposed to 4 or 10 mg L-1 NFLX for 2 or 5 d. Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography (HPLC). Results showed that NFLX residue accumulated in F. chinensis eggs after the parental exposure, with the highest residue detected in ovary. To examine the fate of NFLX residue in larvae, we further determined the concentration of NFLX residue in F. chinensis eggs and larvae at 4 different developmental stages after 24-h exposure. From the newly metamorphosed larvae (0 h post-metamorphosis, h.p.m), samples were taken at different time intervals to 72 h.p.m. HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10 mg L-1 NFLX were the highest at 1.5 h, i.e., 0.332 and 0.454 μg g-1, respectively. At the two NFLX exposure levels, the elimination time of half NFLX (half life) in nauplius was 45.36 and 49.85 h, respectively, followed by that in zoea (31.68 and 33.13 h), mysis larvae (42.24 and 47.28 h) and postlarvae (24.48 and 30.96 h). Both NFLX exposure levels had a germicidal effect. The distribution and elimination of NFLX residue in F. chinensis tissue, eggs and larvae correlated well with the drug exposure level. The disappearance of NFLX residue coincided with the larval growth, and the half-life of NFLX decreased with the larval development.

Evaluation of in vitro and in vivo nematicidal potential of a multifunctional streptomycete, Streptomyces hydrogenans strain DH16 against Meloidogyne incognita.

PubMed

Kaur, Talwinder; Jasrotia, Shivam; Ohri, Puja; Manhas, Rajesh Kumari

2016-11-01

The present work demonstrated the nematicidal potential of Streptomyces hydrogenans strain DH16 (a strain with strong antagonism against fungal phytopathogens and insect pest) against Meloidogyne incognita. The culture supernatant and solvent extract significantly inhibited egg hatching (almost 100%) along with J2 mortality of more than 95% after 96h. The nematicidal activity of 10-(2,2-dimethyl-cyclohexyl)-6,9-dihydroxy-4,9-dimethyl-dec-2-enoic acid methyl ester (SH2; a new antifungal compound) purified from this streptomycete was also evaluated using different concentrations. The juvenile mortality of the nematode increased with increasing concentration and exposure time and reached the maximum (95%) after 96h at concentration of 100μg/ml. After 160h of incubation, egg hatch of 16% was observed at concentration of 100μg/ml as compared to control where 100% egg hatching was achieved. However, at the highest concentration of the compound (200μg/ml), 100% J2 mortality and 0% egg hatching were observed after 72 and 160h of incubation, respectively. In vivo pot experiments further revealed the nematicidal potential of S. hydrogenans where soil drenching with its culture supernatant and cells effectively controlled root galls, egg masses in nematode infested tomato plants and at the same time promoted the growth of tomato plants. Additionally, in the absence of nematodes, soil drenching with culture supernatant and cells significantly enhanced the various agronomic traits of plants as compared to control plants. Thus, the outcomes of the current study endorse the potential of S. hydrogenans strain DH16 and its metabolites to be developed as safe nematicidal and plant growth promoting agents. Copyright © 2016 Elsevier GmbH. All rights reserved.

A singleplex real-time fluorescence resonance energy transfer PCR with melting curve analysis for the differential detection of Paragonimus heterotremus, Echinostoma malayanum and Fasciola gigantica eggs in faeces.

PubMed

Tantrawatpan, Chairat; Saijuntha, Weerachai; Manochantr, Sirikul; Kheolamai, Pakpoom; Thanchomnang, Tongjit; Sadaow, Lakkhana; Intapan, Pewpan M; Maleewong, Wanchai

2016-01-01

Because the eggs of Paragonimus, Echinostoma and Fasciola are very similar in size and shape, it is difficult to distinguish and accurately identify species by the morphology of their eggs, which is a standard diagnostic method. In this study, a novel assay combining a real-time fluorescence resonance energy transfer PCR and melting curve analysis using one set of primers and fluorophore-labelled hybridization probes specific for the 28S rDNA region was developed for the molecular detection of Paragonimus heterotremus, Echinostoma malayanum and Fasciola gigantica eggs. This assay could detect and distinguish P. heterotremus, E. malayanum and F. gigantica DNA with the distinct melting temperature (Tm) values of 57.99±0.08, 62.12±0.15 and 74.10±0.18, respectively. The assay can also be used to detect and distinguish DNA from P. bangkokensis, P. harinasutai, P. machorchis, E. revolutum, Hypodereum conoideum and F. hepatica, which have different Tm values. The sensitivity of this assay enabled the detection of one egg of P. heterotremus, E. malayanum or F. gigantica per 100 mg of faeces. In addition, the specificity testing showed no fluorescence signal for other parasites. Due to the sensitivity and specificity of our assay in detecting P. heterotremus, E. malayanum and F. gigantica, our method could be used to accurately diagnose these three medically important parasitic groups and has potential implications for molecular epidemiological investigations of human and/or animal infections. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Development of Urinary Bladder Pre-Neoplasia by Schistosoma haematobium Eggs and Chemical Carcinogen in Mice

PubMed Central

Chala, Bayissa; Choi, Min-Ho; Moon, Kyung Chul; Kim, Hyung Suk; Kwak, Cheol; Hong, Sung-Tae

2017-01-01

Schistosoma haematobium is a biocarcinogen of human urinary bladder (UB). The present study investigated developing UB cancer mouse model by injecting S. haematobium eggs into the bladder wall and introduction of chemical carcinogens. Histopathological findings showed mild hyperplasia to epithelial vacuolar change, and high grade dysplasia. Squamous metaplasia was observed in the S. haematobium eggs+NDMA group at week 12 but not in other groups. Immunohistochemistry revealed significantly high expression of Ki-67 in urothelial epithelial cells of the S. haematobium eggs+BBN group at week 20. The qRT-PCR showed high expression of p53 gene in S. haematobium eggs group at week 4 and S. haematobium eggs+BBN group at week 20. E-cadherin and vimentin showed contrasting expression in S. haematobium eggs+BBN group. Such inverse expression of E-cadherin and vimentin may indicate epithelial mesenchymal transition in the UB tissue. In conclusion, S. haematobium eggs and nitrosamines may transform UB cells into squamous metaplasia and dysplasia in correlation with increased expression of Ki-67. Marked decrease in E-cadherin and increase in p53 and vimentin expressions may support the transformation. The present study introduces a promising modified animal model for UB cancer study using S. haematobium eggs. PMID:28285503

Thermal tolerance during early ontogeny in the common whelk Buccinum undatum (Linnaeus 1785): Bioenergetics, nurse egg partitioning and developmental success

NASA Astrophysics Data System (ADS)

Smith, Kathryn E.; Thatje, Sven; Hauton, Chris

2013-05-01

Temperature is arguably the primary factor affecting development in ectotherms and, as a result, may be the driving force behind setting species' geographic limits. The shallow-water gastropod Buccinum undatum is distributed widely throughout the North Atlantic, with an overall annual thermal range of below zero to above 22 °C. In UK waters this species is a winter spawner. Egg masses are laid and develop when sea temperatures are at their coolest (4 to 10 °C) indicating future climate warming may have the potential to cause range shifts in this species. In order to examine the potential impacts of ocean warming, we investigate the effects of temperature on the early ontogeny of B. undatum across a thermal range of 0 to 22 °C. Each egg mass consists of approximately 100 capsules, in which embryos undergo direct development. Successful development was observed at temperatures ranging from 6 to 18 °C. Rates of development increased with temperature, but the proportion of each egg mass developing successfully decreased at the same time. With increasing temperature, the mean early veliger weight increased, but the number of early veligers developing per capsule decreased, suggesting a negative impact on the number of crawl-away juveniles produced per capsule. Elemental analysis showed both carbon (C) and nitrogen (N) to increase with temperature in early veligers but not in hatching juveniles, indicating greater energy reserves are accumulated during early ontogeny to compensate for the higher energetic demands of development at higher temperature. The developmental plasticity observed in B. undatum suggests this species to be capable of adapting to temperatures above those it currently experiences in nature. B. undatum may possess a thermal resilience to ocean warming at its current upper temperature distribution limit. This thermal resilience, however, may come at the cost of a reduced offspring number.

Host location and host discrimination behavior of Telenomus isis, an egg parasitoid of the African cereal stem borer Sesamia calamistis.

PubMed

Chabi-Olaye, A; Schulthess, F; Poehling, H M; Borgemeister, C

2001-04-01

In the Republic of Benin, the scelionid egg parasitoid Telenomus isis (Polaszek) is one of the most important control factors of the noctuid maize stem borer Sesamia calamistis. In the present study, the role of various sources of contact kairomones (male or virgin or mated female moths) and of the moth's oviposition substrate (leaf sheath versus filter paper: host plant species) in host location and oviposition behavior of T. isis was investigated in Munger cells, open arenas, and/or Petri dish assays. Furthermore, its ability to distinguish between unparasitized eggs and eggs parasitized by a conspecific female or by the trichogrammatid Lathromeris ovicida was studied. In the Munger cell experiment, T. isis spent more time in moths' odor fields than in the control. There was no difference between virgin and mated females. In the open arena assay, traces left by both the male and female moths acted as contact cues, which elicited an arrestment response in the parasitoid. The residence and patch retention time in the arena with virgin or mated females of S. calamistis was about 4.8 times as long as that with males. The presence of maize leaf sheaths stimulated the oviposition behavior of T. isis when compared to eggs offered on filter paper. During the first 6 hr, more eggs were parasitized on maize leaves, although there was no difference in the final number of offspring between the two substrates. In addition, if eggs of S. calamistis were offered together with different host plant species or alone, maize and sorghum were both more attractive than millet or the egg alone and equally attractive between themselves, indicating that the plant tissue influences host finding of T. isis. Both T. isis and L. ovicida recognized markings of conspecific females, and intraspecific superparasitism was therefore low. Interspecific superparasitism was more than three times higher for L. ovicida than for T. isis, indicating that only T. isis was able to recognize the marking of the other species and tried to avoid superparasitism. Emergence of parasitoids from multiparasitized eggs generally was in favor of L. ovicida regardless of species order.

Effects of in ovo injection of carbohydrates on embryonic metabolism, hatchability, and subsequent somatic characteristics of broiler hatchlings.

PubMed

Zhai, W; Gerard, P D; Pulikanti, R; Peebles, E D

2011-10-01

The effects of the in ovo injection of different carbohydrate solutions on the internal egg temperature (IT), hatchability, and time of hatch of embryonated Ross × Ross 708 broiler hatching eggs were determined. In addition, the BW, liver weight, yolk sac weight (YSW), and yolk-free BW (YFBW) of the embryos on d 19.5 of incubation and of the chicks on day of hatch were determined. Eggs containing live embryos were injected in the amnion on d 18.5 of incubation using an automated multiple-egg injector. Solution injections delivered 1.2 mL of physiological saline (0.85%) alone or with a supplemental carbohydrate. The following supplemental carbohydrates were separately dissolved in saline at a concentration of 0.3 g/mL: glucose, fructose, sucrose, maltose, and dextrin. Temperature transponders were implanted in the air cells of embryonated and nonembryonated eggs after in ovo injection for the detection of IT at 6, 14, and 22 h after injection. The IT of embryonated eggs was significantly greater than that of nonembryonated eggs at all 3 times after the treatment period. Eggs that were injected with saline with or without supplemental carbohydrates experienced a reduction in IT when compared with control eggs whose shells were perforated without solution delivery, and the decrease in IT was associated with a delay in hatch time. Liver weight was negatively related to YSW and positively related to YFBW, and YSW was negatively related to YFBW. Although the saline and carbohydrate solution injections increased chick BW compared with noninjected controls, chick YFBW was decreased in the maltose- and sucrose-injected groups. In conclusion, the injection of 1.2 mL of saline with or without supplemental carbohydrates lowered embryonic metabolism, as reflected by a lower IT and a delay in time of hatch. However, effects of the different carbohydrate solutions on yolk absorption and tissue deposition in yolk-free embryos varied. These results suggest that lower volumes for solutions containing maltose, sucrose, or fructose should be considered for in ovo injection.

Elevated PCDD/F levels and distinctive PCDD/F congener profiles in free range eggs.

PubMed

Hsu, Jing-Fang; Chen, Chun; Liao, Pao-Chi

2010-07-14

Chicken eggs are one of the most important foods in the human diet all over the world, and the demand for eggs from free range hens has steadily increased. Congener-specific analyses of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were performed on 6 free range and 12 caged chicken egg samples collected in Taiwan. The mean level of PCDD/Fs in the free range egg samples was 5.7 (1.79/0.314) times higher than those in the caged egg samples. Principle component analysis revealed that at least three characteristic patterns of PCDD/F congener were observed among the 18 egg samples. The different PCDD/F congener patterns between free range and caged egg samples may reflect distinctive exposure scenarios among the free range and caged hens. We suggest that the differences of PCDD/F levels and congener patterns between free range and caged egg samples give rise to the issues related to the safety of eating free range chicken eggs. The present data may provide useful information for further investigation of the possible PCDD/F sources in the contaminated free range eggs.

Dungeness crab, Cancer magister, do not extrude eggs annually in southeastern Alaska: An in situ study

USGS Publications Warehouse

Swiney, K.M.; Shirley, Thomas C.; Taggart, S. James; O'Clair, Charles E.

2003-01-01

The reproductive biology of female Dungeness crabs was studied with crab-pot and dive-transect sampling in five bays within or near Glacier Bay National Park and Preserve, southeastern Alaska, in April and September yearly from 1992 to 1998. A large percentage of nonovigerous, mature females was found in April, a time when females were expected to be brooding eggs that hatch in May and June. Our study examined differences between ovigerous and nonovigerous females collected in April and September samples to corroborate our previous laboratory study in which we found nonannual egg extrusion among Dungeness crabs. Seasonal differences in the catches of ovigerous and nonovigerous females, crab sizes, shell condition, and appendage injury were examined. Additionally, all crabs collected from two bays were tagged beginning in the fall of 1995; tagging was conducted twice annually. Our pot and dive data indicate that females, particularly larger ones, do not extrude eggs annually. Larger females have lower molting probabilities, which limits mating potential and increases reliance on stored sperm. The tagging study confirmed that at least some females do not extrude eggs in one year and then extrude eggs at a later time without molting, thus skipping at least one reproductive season. A reproductive cycle of Dungeness crabs in Alaska is introduced which includes earlier egg extrusion by larger females and nonannual egg extrusion.

Inactivation kinetics of a four-strain composite of Salmonella Enteritidis and Oranienberg in commercially-acquired liquid egg yolk

USDA-ARS?s Scientific Manuscript database

Introduction: Current liquid egg pasteurization requirements are based on command and control prescribed time/temperature combinations for specified egg products. Requirements are found in the Code of Federal Regulations, Title 9, Ch. III, Sec. 590.570. These standards were based on data for the ...

Round goby Neogobius melanostomus attraction to conspecific and heterospecific egg odours.

PubMed

Yavno, S; Corkum, L D

2011-06-01

In this study, cannibalistic and predatory responses of juvenile Neogobius melanostomus (either fed or deprived of food and caught during the reproductive summer or non-reproductive winter season) to water washings of fertilized eggs from conspecifics (N. melanostomus), heterospecifics (rainbow trout Oncorhynchus mykiss) and control lake water were tested. Fed juveniles (summer season) spent significantly more time on the side of the flume containing stimuli from conspecific eggs over control water, while significantly preferring control water to heterospecific stimuli. In addition, fish showed a significant preference towards stimuli from conspecific eggs over heterospecific stimuli by associating near conspecific egg odours 1·5 times longer [Correction added after online publication 28 April 2011, text changed]. Fish that were deprived of food, regardless of whether caught during the summer or winter season, did not show any preference towards either conspecific or heterospecific stimuli. These findings show that conspecific egg odours attract fed juveniles and that there is a potential to lure fish to odour traps as a means of control. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Coexposure of dioxin-like polychlorinated biphenyls and polychlorinated dibenzo-p-dioxins and dibenzofurans in free-range hens and implications derived from congener profile analysis.

PubMed

Lin, Chingju; Hsu, Jing-Fang; Liao, Pao-Chi

2012-02-29

The consumption of free-range eggs is becoming more popular worldwide. We analyzed the levels of 12 dioxin-like polychlorinated biphenyls (dl-PCBs) and their congener profiles from 6 free-range and 12 caged egg samples. The mean levels of dl-PCBs in the free-range samples were 5.4 times higher than those in caged eggs. All egg samples exhibited at least two characteristic dl-PCB congener patterns, which reflected distinctive contamination sources. Additionally, for the first time, we demonstrated that the dl-PCB levels in the free-range eggs were highly correlated with elevated levels of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) (r = 0.986; p < 0.001), indicating a coexposure scenario in free-range hens. Cluster analysis of congener patterns implied that this coexposure scenario could be attributed to distinct dl-PCB and PCDD/F sources. This congener profile information provides insights from a different perspective for further identifying potential dl-PCB and PCDD/F sources in the polluted free-range eggs.

Life history attributes of the rare mayfly Siphlonisca aerodromia Needham (Ephemeroptera:Siphlonuridae)

USGS Publications Warehouse

Gibbs, K.E.; Siebenmann, M.

1996-01-01

Over a 3-y period, we examined the biology of late-instar nymphs, adults, and eggs of the rare predaceous mayfly S. aerodromia at Tomah Stream, Maine, to identify life history attributes associated with the mayfly's movements between the stream channel and the bordering floodplain. Eggs were deposited in the stream channel in June and hatched in November and December. Embryonic development occurred in 47-92% of eggs from unmated females. With rising water levels following snowmelt in March or April, nymphs moved from channel to floodplain, where most nymphal growth and development took place. Sex ratios of nymphs in the floodplain were female biased (1 M:1.4 F in 1991 and 1 M:2.1 F in 1992). Nymphs molted to the final instar earlier in 1991 than in 1992 and male nymphs molted to the final instar before female nymphs in 1991 but not 1992. Time in the final instar decreased as the season advanced. Seasonal emergence was protandrous and lasted 10-11 d during late May and early June; timing of seasonal emergence in 1991, 1992, and 1993 was related to maximum air temperatures and persistence of standing water in the floodplain during May. Emergence of subimagos was female biased in 1991, but male biased in 1992. Diel emergence was from 0700 to 1700 h (EST) and occurred only when water temperature was >11??C.

Egg cases of the genus Apristurus (Chondrichthyes: Scyliorhinidae): phylogenetic and ecological implications.

PubMed

Flammang, Brooke E; Ebert, David A; Cailliet, Gregor M

2007-01-01

The genus Apristurus has been divided formerly into three species subgroups based on morphological and molecular phylogenies. Previous studies have agreed on the separation into distinct species groups, the largest two of which have been described as the brunneus and spongiceps groups. An examination of the egg cases produced by these oviparous catsharks corroborates the distinction in species groups: egg cases of the brunneus group have long fibrous and curly tendrils at either end, whereas egg cases of the spongiceps group lack tendrils. The egg cases of A. kampae, A. manis, A. spongiceps and Apristurus sp. D are described for the first time, and the egg cases of A. brunneus and A. riveri are re-described to include comparable morphological characteristics. The ecological implications of egg case morphology on oviposition and ventilation are also discussed.

Microbial infections are associated with embryo mortality in Arctic-nesting geese.

USGS Publications Warehouse

Hansen, Cristina M.; Meixell, Brandt W.; Van Hemert, Caroline R.; Hare, Rebekah F.; Hueffer, Karsten

2015-01-01

To address the role of bacterial infection in hatching failure of wild geese, we monitored embryo development in a breeding population of Greater white-fronted geese (Anser albifrons) on the Arctic Coastal Plain of Alaska. During 2013, we observed mortality of normally developing embryos and collected 36 addled eggs for analysis. We also collected 17 infertile eggs for comparison. Using standard culture methods and gene sequencing to identify bacteria within collected eggs, we identified a potentially novel species of Neisseria in 33 eggs, Macrococcus caseolyticus in 6 eggs, and Streptococcus uberis and Rothia nasimurium in 4 eggs each. We detected seven other bacterial species at lower frequencies. Sequences of the 16S rRNA genes from the Neisseria isolates most closely matched sequences from N. animaloris and N. canis (96 to 97% identity), but phylogenetic analysis suggested substantial genetic differentiation between egg isolates and known Neisseria species. Although definitive sources of the bacteria remain unknown, we detected Neisseria DNA from swabs of eggshells, nest contents, and cloacae of nesting females. To assess the pathogenicity of bacteria identified in contents of addled eggs, we inoculated isolates of Neisseria, Macrococcus, Streptococcus, and Rothia at various concentrations into developing chicken eggs. Seven-day mortality rates varied from 70 to 100%, depending on the bacterial species and inoculation dose. Our results suggest that bacterial infections are a source of embryo mortality in wild geese in the Arctic.    

Influence of ambient ultraviolet radiation on Bufo calamita egg development in a semiarid zone (Catalonia, Spain).

PubMed

Oromi, Neus; Marquis, Olivier; Miaud, Claude; Sanuy, Delfi

2008-01-01

Several experiments have shown that ambient ultraviolet-B radiation (UV-B) has negative effects on the development of amphibians' embryos. We studied the effects of UV-B radiation on development, survival and frequency of deformity during egg development in the Natterjack toad (Bufo calamita) from a semiarid region of Lleida (Catalonia, Spain). Eggs exposed to ambient levels of UV-B and those protected from UV-B with a filter exhibited similar developmental rate, mortality rate and frequency of developmental anomalies. These experiments show that eggs of Bufo calamita of the studied population are able to develop normally during embryonic period when exposed to current high levels of UV-B observed in Catalonia. These results will be used as reference for future studies on geographic variation in UV-B tolerance in this species.

Higher Storage Temperature Causes Greater Salmonella enterica Serovar Typhimurium Internal Penetration of Artificially Contaminated, Commercially Available, Washed Free Range Eggs.

PubMed

Whiley, Alice; Fallowfield, Howard; Ross, Kirstin; McEvoy, Vanessa; Whiley, Harriet

2016-07-01

Foodborne salmonellosis is a major public health concern, with contaminated eggs identified as a significant source of infection. In Australia, the most prevalent cause of salmonellosis from eggs is Salmonella enterica subsp. enterica serovar Typhimurium. This study explored the effect of temperature after 1, 7, 14, 21, and 28 days of storage on commercially available washed free range eggs, artificially contaminated with Salmonella Typhimurium on the external surface. At each time point, the external surface of the egg, the crushed eggshell, and the internal egg yolk and albumen were analyzed for Salmonella. After 28 days of storage, 25% of eggs stored at 4°C, 50% of eggs stored at 14°C, and 100% of eggs stored at 23 and 35°C were internally contaminated with Salmonella. After 1 day of storage, more than 50% of all eggs had Salmonella present in the crushed shell after the external surface had been disinfected with ethanol. This is the first study to demonstrate that refrigeration reduced the potential for Salmonella Typhimurium to penetrate the eggshell membrane and internally contaminate table eggs commercially available in Australia. It also suggests that the processes of cracking eggs may be a source of cross-contamination within the kitchen.

Becoming a mother by non-anonymous egg donation: secrecy and the relationship between egg recipient, egg donor and egg donation child.

PubMed

van Berkel, D; Candido, A; Pijffers, W H

2007-06-01

The object of the study was to investigate secrecy in non-anonymous egg donation, to explore some characteristics of this kind of egg donation arrangement and the relationship of the recipient with her non-genetic child. Forty-four egg recipients and 62 IVF patients with a child conceived through egg donation and/or IVF were recruited. A semi-structured questionnaire was sent to all the participants. Chi-square and T-tests were used to examine the differences between the groups. There were no significant differences on the following aspects. The same high proportion of egg donation mothers (77%) and IVF mothers (87%) had the intention of telling their child about the conception but most women thought disclosure at a later time preferable. Two thirds of the recipients and IVF mothers said the way of conception had no influence on the relationship with their child. The two groups differed however in their argumentation about secrecy and named different feelings. Egg donation mothers expressed more denial and showed more defensive reactions, anxieties and uncertainty. It is suggested that recognition of a certain difference between a natural conception and egg donation could be helpful in early disclosure and could help to diminish anxieties in egg donation mothers.

Biological variation in two Anopheles vestitipennis populations with different feeding preferences in southern Mexico.

PubMed

Ulloa, Armando; Rodríguez, Mario H; Arredondo-Jimenez, Juan I; Fernandez-Salas, Ildefonso

2005-12-01

The lengths of gonotrophic cycle and egg development and survival rate were studied in Anopheles vestitipennis collected in horse and human-baited traps in southern Mexico. The gonotrophic cycle duration was estimated using cross-correlation analysis, whereas the survival rate was assessed using a vertical method. Daily changes of parity rates gave significant correlation indices at 3 and 4 days in the zoophilic and anthropophilic populations, respectively. The minimum time required to develop mature eggs after blood feeding was 54 and 60 h, and the survival rate was 0.93 and 0.88 in zoophilic and anthropophilic female mosquito populations, respectively. These biological differences provide additional support for the existence of subpopulations with distinctive feeding preferences within An. vestitipennis in southern Mexico.

Field Acceptance and Nutritional Intake of the Meal, Ready-to-Eat and Heat and Serve Ration.

DTIC Science & Technology

1998-05-01

Scrambled Eggs (Natick) and Scrambled Eggs w/Bacon(Natick). These two mean ratings were received from the control group. Table 4A Control Group H&S...6.4 Creamed Ground Beef 6.3 Corned Beef Hash 6.1 Western Scrambled Eggs (Natick)* 4.6 Scrambled Eggs w...5.4 20 38 33 * Natick - NRDEC developed eggs Table 4B Test Group H&S Breakfast Acceptability Ratings (n=39) Food Groups Food Item Entrees

Forskolin-induced differentiation of BeWo cells stimulates increased tumor growth in the chorioallantoic membrane (CAM) of the turkey (Meleagris gallopavo) egg.

PubMed

Schneider, Ralf; Borges, Marcus; Kadyrov, Mamed

2011-05-01

Invasiveness of BeWo cells has been assessed in a variety of assay systems including matrigel and mouse. At the same time BeWo cells are mostly used as model system for trophoblast fusion. Here we aimed to test the properties of BeWo cells in a combined approach. We forced BeWo cells to differentiate by culturing the cells in the presence of forskolin and then used these cells for invasion assays on the chorioallantoic membrane (CAM) of the turkey. The chorioallantoic membranes of turkey eggs were incubated with medium containing forskolin, BeWo cells cultured in medium alone, BeWo cells cultured in forskolin and washed, and BeWo cells cultured in forskolin and used directly for application. Suspensions were applied onto ten CAM per condition. For local tumor formation eggs were checked for tumor development every 24h macroscopically for up to 12 days and immunohistochemistry for cytokeratin 18 and Ki-67 were used for further analysis. Forskolin alone did not have any deleterious effect on the CAM. When the CAM was incubated with BeWo cells cultured in medium 40% of the eggs developed a macroscopically visible tumor. BeWo cells stimulated with forskolin and washed induced tumor growth in 50% of the eggs, while forskolin stimulated BeWo cells applied directly onto the CAM induced tumor growth in 70% of the eggs. Forced differentiation of BeWo cells by forskolin may lead to syncytial fusion in a plastic culture dish. Under the conditions used here, i.e. in direct contact to a living tissue, forskolin-induced differentiation of BeWo cells leads to an increase in tumor formation in the CAM. Thus BeWo cells may use signaling pathways to decide for both differentiation pathways similar to primary trophoblast depending on the environment. Copyright © 2011 Elsevier GmbH. All rights reserved.

Association of egg consumption and calcified atherosclerotic plaque in the coronary arteries: the NHLBI Family Heart Study

PubMed Central

Robbins, Jeremy M.; Petrone, Andrew B.; Ellison, R. Curtis; Hunt, Steven C.; Carr, J. Jeffrey; Heiss, Gerardo; Arnett, Donna K.; Gaziano, J. Michael; Djoussé, Luc

2015-01-01

Background and Aims Eggs are a ubiquitous and important source of dietary cholesterol and nutrients, yet their relationship to coronary heart disease (CHD) remains unclear. While some data have suggested a positive association between egg consumption and CHD, especially among diabetic subjects, limited data exist on the influence of egg consumption on subclinical disease. Thus, we sought to examine whether egg consumption is associated with calcified atherosclerotic plaques in the coronary arteries. Methods In a cross-sectional design, we studied 1848 participants of the NHLBI Family Heart Study without known CHD. Egg consumption was assessed by a semi-quantitative food frequency questionnaire and coronary-artery calcium (CAC) was measured by cardiac CT. We defined prevalent CAC using an Agatston score of at least 100 and fitted generalized estimating equations to calculate prevalence odds ratios of CAC. Results Mean age was 56.5 years and 41% were male. Median consumption of eggs was 1/week. There was no association between frequency of egg consumption and prevalent CAC. Odds ratios (95% CI) for CAC were 1.0 (reference), 0.95 (0.66-1.38), 0.94 (0.63-1.40), and 0.90 (0.57-1.42) for egg consumption of almost never, 1-3 times per month, once per week, and 2+ times per week, respectively (p for trend 0.66), adjusting for age, sex, BMI, smoking, alcohol, physical activity, income, field center, total calories, and bacon. Additional control for hypertension and diabetes mellitus, or restricting the analysis to subjects with diabetes mellitus or fasting glucose >126 mg/dL did not alter the findings. Conclusions These data do not provide evidence for an association between egg consumption and prevalent CAC in adult men and women. PMID:25642410

Egg Production in a Coastal Seabird, the Glaucous-Winged Gull (Larus glaucescens), Declines during the Last Century

PubMed Central

Blight, Louise K.

2011-01-01

Seabirds integrate information about oceanic ecosystems across time and space, and are considered sensitive indicators of marine conditions. To assess whether hypothesized long-term foodweb changes such as forage fish declines may be reflected in a consumer's life history traits over time, I used meta-regression to evaluate multi-decadal changes in aspects of egg production in the glaucous-winged gull (Larus glaucescens), a common coastal bird. Study data were derived from literature searches of published papers and unpublished historical accounts, museum egg collections, and modern field studies, with inclusion criteria based on data quality and geographic area of the original study. Combined historical and modern data showed that gull egg size declined at an average of 0.04 cc y−1 from 1902 (108 y), equivalent to a decline of 5% of mean egg volume, while clutch size decreased over 48 y from a mean of 2.82 eggs per clutch in 1962 to 2.25 in 2009. There was a negative relationship between lay date and mean clutch size in a given year, with smaller clutches occurring in years where egg laying commenced later. Lay date itself advanced over time, with commencement of laying presently (2008–2010) 7 d later than in previous studies (1959–1986). This study demonstrates that glaucous-winged gull investment in egg production has declined significantly over the past ∼50–100 y, with such changes potentially contributing to recent population declines. Though gulls are generalist feeders that should readily be able to buffer themselves against food web changes, they are likely nutritionally constrained during the early breeding period, when egg production requirements are ideally met by consumption of high-quality prey such as forage fish. This study's results suggest a possible decline in the availability of such prey, and the incremental long-term impoverishment of a coastal marine ecosystem bordering one of North America's rapidly growing urban areas. PMID:21789207

Effects of salinity on striped bass eggs and larvae from the Savannah River, Georgia

USGS Publications Warehouse

Winger, P.V.; Lasier, P.J.

1994-01-01

Operation of a tide gate installed in the Savannah River by the U.S. Army Corps of Engineers to reduce dredging activities increased salinities upstream in important spawning habitat for striped bass Morone saxatilis. To assess the effects of salinity on survival and growth of striped bass at early life stages, newly fertilized eggs and 48-h-posthatch were exposed to serial dilutions of seawater, with salinities ranging from 0 to 33 permill (g/L) in increments of 3 permill in addition, older larvae (5-d posthatch) were exposed to salinities of 0, 6, 12, 18, and 24 permill. Eggs were exposed until 24 h posthatch, 48-h-posthatch larvae were exposed for 10 d, and 5-d-posthatch larvae were exposed for 6 d. Eggs died within 24 h in salinities greater than 18 permill. Both survival and total length of larvae hatched from eggs exposed to salinities of 15 permill or higher were reduced. Percent mortality and mean total lengths of newly hatched larvae followed the same pattern for each of three sets of salinity regimes (i.e., changes in salinities over time) that striped bass eggs might encounter during passage downstream in the Savannah River. Hardening eggs in freshwater did not increase survival or length of hatched larvae over that shown by eggs hardened in saline water. The 5-d-posthatch larvae were less sensitive to salinity than the 48-h-posthatch larvae. Survival of larvae was negatively con-elated with both salinity and exposure time. For 48-h-posthatch larvae, the 10-d LC50 (the salinity lethal to 50% of the test fish within 10 d) was 10 permill. Probabilities of survival for larval striped bass exposed to different salinities for different amounts of time can be estimated from curves generated from models of survival analysis. Salinities judged to be critical to Savannah River striped bass eggs and larvae are those greater than 9 permill.

The relationship of incubational egg weight loss with parthenogenesis in Chinese Painted quail (Coturnix chinensis).

PubMed

Wells, J B; Parker, H M; Kiess, A S; McDaniel, C D

2012-01-01

Parthenogenesis, embryonic development of an unfertilized egg, has been studied extensively in turkeys. Recently it has been revealed that parthenogenesis also occurs in Chinese Painted quail, and the percentage of eggs exhibiting parthenogenesis is negatively correlated with clutch sequence position. In broiler breeders, it has been reported that the first egg of a clutch sequence loses less egg weight during incubation than subsequent eggs. Because the incidence of parthenogenesis is greater and egg weight loss is less in the first egg of a clutch sequence, it is possible that egg weight loss is less in parthenogenetic eggs. Therefore, the objective of this study was to determine if a relationship exists between egg weight loss (a measure of eggshell quality) and parthenogenesis. Daily, individual eggs were collected and labeled. To determine egg weight loss, eggs were weighed before setting and then again after 10 d of incubation. Eggs were stored for 0 to 3 d at 20°C and incubated at 37.5°C. Pearson correlation coefficients were used to determine if relationships existed between egg weight loss and average incidence of parthenogenesis, parthenogen size, egg storage, and average clutch sequence position for all hens examined (157) as well as only for hens that exhibited parthenogenesis (102). The percentage of egg weight loss was negatively correlated with the incidence of parthenogenetic eggs and parthenogen size. However, the percentage of egg weight loss was positively correlated with average clutch position. In conclusion, it appears that eggshell quality possibly influences the incidence of parthenogenesis in Chinese Painted quail eggs because as the percentage of egg weight loss decreases, the incidence of parthenogenesis increases.

An estimation of carrying capacity for sea otters along the California coast

USGS Publications Warehouse

Laidre, K.L.; Jameson, R.J.; DeMaster, D.P.

2001-01-01

Eggs of wild birds collected for the purpose of measuring concentrations of pesticides or other pollutants vary from nearly fresh to nearly dry so that objective comparisons cannot be made on the basis of weight of the contents at the time of collection. Residue concentrations in the nearly dry eggs can be greatly exaggerated by this artifact. Valid interpretation of residue data depends upon compensation for these losses. A method is presented for making adjustments on the basis of volume of the egg, and formulas are derived for estimating the volume of eggs of eagles, ospreys, and pelicans from egg measurements. The possibility of adjustments on the basis of percentage of moisture, solids, or fat in fresh eggs is discussed also.

FonaDyn - A system for real-time analysis of the electroglottogram, over the voice range

NASA Astrophysics Data System (ADS)

Ternström, Sten; Johansson, Dennis; Selamtzis, Andreas

2018-01-01

From soft to loud and low to high, the mechanisms of human voice have many degrees of freedom, making it difficult to assess phonation from the acoustic signal alone. FonaDyn is a research tool that combines acoustics with electroglottography (EGG). It characterizes and visualizes in real time the dynamics of EGG waveforms, using statistical clustering of the cycle-synchronous EGG Fourier components, and their sample entropy. The prevalence and stability of different EGG waveshapes are mapped as colored regions into a so-called voice range profile, without needing pre-defined thresholds or categories. With appropriately 'trained' clusters, FonaDyn can classify and map voice regimes. This is of potential scientific, clinical and pedagogical interest.

Supercooling ability is surprisingly invariable in eggs of the land snail Cantareus aspersus.

PubMed

Ansart, Armelle; Madec, Luc; Vernon, Philippe

2007-02-01

From an ontogenetic point of view, invertebrate eggs are generally the most freezing intolerant stage of a species. Development state, water content and acclimation may affect their supercooling ability. In this study, we measured fresh mass, water content and temperature of crystallisation (T(c)) of eggs of the edible land snail Cantareus aspersus, depending on its form ("aspersa"vs. "maxima"), incubation temperature (20, 12 and 7 degrees C) and physiological age (as part of the complete development). We also tested their tolerance to freezing. Despite a high number of individual observations (n=759) and significant differences of fresh mass and water content between both subspecies, no effect of origin, incubation temperature or development state has been found in this study. T(c) remained constant whatever the condition, with an overall mean of -5.40+/-0.24 degrees C (mean+/-SD). We suggest that fresh mass is important, a high water content and a constantly wet surface confer to land snail eggs a poor ability to supercool. Moreover, the presence of ice nucleating agents at the egg surface (microorganisms present in the soil, calcium carbonate crystals of the egg shell) might induce freezing. Thus, considering the present results, to delay hatching by cryopreservation of eggs does not seem possible.

Contaminants in ospreys from the Pacific Northwest: II. Organochlorine pesticides, polychlorinated biphenyls and mercury, 1991-1997

USGS Publications Warehouse

Elliott, J.E.; Macmer, M.M.; Wilson, L.K.; Henny, Charles J.

2000-01-01

Eggs of ospreys (Pandion haliaetus) were collected over the period 1991 to 1997 at 111 nests in the Fraser and Columbia River drainage systems of British Columbia, Washington, and Oregon. Contents were analyzed for organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and total mercury. Blood samples were taken from nestling ospreys at two time points during the 1992 breeding season on the Thompson River and analyzed for non-ortho PCBs. Concentrations of DDE and related compounds showed high variability among individual eggs within study areas and no significant differences in mean concentrations among study areas. Some eggs contained high concentrations of DDE, up to 20 mg/kg (wet weight), for which there were no evident local sources, suggesting that exposure occurred outside of the breeding grounds. Most other OC pesticides measured in osprey eggs showed a similar distribution, although mean concentrations of chlordane-related compounds were generally, and in some cases significantly, higher in samples collected from the Columbia River sites compared to elsewhere. Significantly greater concentrations of PCBs were found in eggs from the Columbia River basin compared to the Fraser. This was attributed to extensive development of hydroelectric generation and related industries on the Columbia system. Significant differences among sites were also found in the pattern of PCB congeners, e.g., eggs from the lower Columbia River site had proportionally greater concentrations of less chlorinated, Aroclor 1242–type PCBs compared to other sites. In contrast, eggs from upper reaches of the Columbia River had relatively greater amounts of Aroclor 1254 and 1260 congeners. Mercury concentrations in osprey eggs tended to be uniform among sites and comparable to those reported in the literature for ospreys nesting on naturally formed lakes and rivers. There were no significant temporal changes in mean concentrations of any of the measured compounds at sites monitored from 1991 to 1997.

Contaminants in ospreys from the Pacific Northwest: II. Organochlorine pesticides, polychlorinated biphenyls, and mercury, 1991-1997.

PubMed

Elliott, J E; Machmer, M M; Wilson, L K; Henny, C J

2000-01-01

Eggs of ospreys (Pandion haliaetus) were collected over the period 1991 to 1997 at 111 nests in the Fraser and Columbia River drainage systems of British Columbia, Washington, and Oregon. Contents were analyzed for organochlorine (OC) pesticides, polychlorinated biphenyls (PCBs), and total mercury. Blood samples were taken from nestling ospreys at two time points during the 1992 breeding season on the Thompson River and analyzed for non-ortho PCBs. Concentrations of DDE and related compounds showed high variability among individual eggs within study areas and no significant differences in mean concentrations among study areas. Some eggs contained high concentrations of DDE, up to 20 mg/kg (wet weight), for which there were no evident local sources, suggesting that exposure occurred outside of the breeding grounds. Most other OC pesticides measured in osprey eggs showed a similar distribution, although mean concentrations of chlordane-related compounds were generally, and in some cases significantly, higher in samples collected from the Columbia River sites compared to elsewhere. Significantly greater concentrations of PCBs were found in eggs from the Columbia River basin compared to the Fraser. This was attributed to extensive development of hydroelectric generation and related industries on the Columbia system. Significant differences among sites were also found in the pattern of PCB congeners, e.g., eggs from the lower Columbia River site had proportionally greater concentrations of less chlorinated, Aroclor 1242-type PCBs compared to other sites. In contrast, eggs from upper reaches of the Columbia River had relatively greater amounts of Aroclor 1254 and 1260 congeners. Mercury concentrations in osprey eggs tended to be uniform among sites and comparable to those reported in the literature for ospreys nesting on naturally formed lakes and rivers. There were no significant temporal changes in mean concentrations of any of the measured compounds at sites monitored from 1991 to 1997.

Variation in maternal effects and embryonic development rates among passerine species

USGS Publications Warehouse

Martin, T.E.; Schwabl, H.

2008-01-01

Embryonic development rates are reflected by the length of incubation period in birds, and these vary substantially among species within and among geographical regions. The incubation periods are consistently shorter in North America (Arizona study site) than in tropical (Venezuela) and subtropical (Argentina) South America based on the study of 83 passerine species in 17 clades. Parents, mothers in particular, may influence incubation periods and resulting offspring quality through proximate pathways, while variation in maternal strategies among species can result from selection by adult and offspring mortality. Parents of long-lived species, as is common in the tropics and subtropics, may be under selection to minimize costs to themselves during incubation. Indeed, time spent incubating is often lower in the tropical and subtropical species than the related north temperate species, causing cooler average egg temperatures in the southern regions. Decreased egg temperatures result in longer incubation periods and reflect a cost imposed on offspring by parents because energy cost to the embryo and risk of offspring predation are both increased. Mothers may adjust egg size and constituents as a means to partially offset such costs. For example, reduced androgen concentrations in egg yolks may slow development rates, but may enhance offspring quality through physiological trade-offs that may be particularly beneficial in longer-lived species, as in the tropics and subtropics. We provide initial data to show that yolks of tropical birds contain substantially lower concentrations of growth-promoting androgens than north temperate relatives. Thus, maternal (and parental) effects on embryonic development rates may include contrasting and complementary proximate influences on offspring quality and deserve further field study among species. ?? 2007 The Royal Society.

Variation in maternal effects and embryonic development rates among passerine species.

PubMed

Martin, Thomas E; Schwabl, Hubert

2008-05-12

Embryonic development rates are reflected by the length of incubation period in birds, and these vary substantially among species within and among geographical regions. The incubation periods are consistently shorter in North America (Arizona study site) than in tropical (Venezuela) and subtropical (Argentina) South America based on the study of 83 passerine species in 17 clades. Parents, mothers in particular, may influence incubation periods and resulting offspring quality through proximate pathways, while variation in maternal strategies among species can result from selection by adult and offspring mortality. Parents of long-lived species, as is common in the tropics and subtropics, may be under selection to minimize costs to themselves during incubation. Indeed, time spent incubating is often lower in the tropical and subtropical species than the related north temperate species, causing cooler average egg temperatures in the southern regions. Decreased egg temperatures result in longer incubation periods and reflect a cost imposed on offspring by parents because energy cost to the embryo and risk of offspring predation are both increased. Mothers may adjust egg size and constituents as a means to partially offset such costs. For example, reduced androgen concentrations in egg yolks may slow development rates, but may enhance offspring quality through physiological trade-offs that may be particularly beneficial in longer-lived species, as in the tropics and subtropics. We provide initial data to show that yolks of tropical birds contain substantially lower concentrations of growth-promoting androgens than north temperate relatives. Thus, maternal (and parental) effects on embryonic development rates may include contrasting and complementary proximate influences on offspring quality and deserve further field study among species.

Kinematics of gray crescent formation in Xenopus eggs: the displacement of subcortical cytoplasm relative to the egg surface.

PubMed

Vincent, J P; Oster, G F; Gerhart, J C

1986-02-01

Specification of the amphibian dorso-ventral axis takes place in the period between fertilization and first cleavage when the gray crescent forms. In the course of gray crescent formation, the egg reorganizes its periphery by a movement for which two descriptions have been given. According to the "rotation hypothesis," which was originated and supported for Rana eggs, the entire egg cortex rotates by an arc of 30 degrees relative to the stationary subcortical cytoplasm, leaving the crescent as a zone of altered coloration. The "contraction hypothesis" on the other hand, which was proposed for Xenopus and Rana eggs, asserts that there is a cortical contraction focused at the sperm entry point that leads to stretching of the opposite equatorial zone at which the crescent appears. We have reinvestigated the case of Xenopus eggs by imprinting one kind of fluorescent dye pattern (Nile blue) onto the subcortical cytoplasm and another kind (fluorescein-lectin) onto the egg surface. When the egg surface is held fixed by embedding the egg in gelatin, two major movements of the subcortical cytoplasm are observable. First, starting at time 0.3 (30% of the time between fertilization and first cleavage), the animal hemisphere subcortical cytoplasm converges toward a point, while the vegetal hemisphere is quiescent. This convergence continues with decreasing strength until approximately 0.8 of the first cell cycle. Second, at 0.45, an overall rotation of the animal and vegetal subcortical cytoplasm commences, superimposed on the animal hemisphere convergence. By 0.8-0.9 the rotation is complete, having accomplished a 30 degrees displacement of the subcortical cytoplasm relative to the surface. This rotation reliably locates the future dorsal midline of the embryo at the meridian on which the displacement of the subcortical cytoplasm is greatest in a vegetal direction. In normal unembedded eggs, when the egg surface is free to move, it rotates 30 degrees relative to the subcortical cytoplasm, which remains stationary in a position of gravitational equilibrium. Although both a convergence and rotation occur in the Xenopus egg, we give evidence that the rotation, not the convergence (perhaps equated with contraction), specifies the embryo's prospective axis. Even though the Xenopus egg does not form a classical gray crescent, due to its particular pigment distribution, the reorganization process which specifies the future embryonic axis resembles that of the Rana egg.

Cytoplasmic rearrangements associated with amphibian egg symmetrization

NASA Technical Reports Server (NTRS)

Malacinski, G. M.

1984-01-01

Cytoplasmic rearrangements which follow fertilization were mentioned in normal and inverted eggs. A set of yolk compartments was resolved by cytological analyses of both normally oriented and inverted eggs. Those compartments were characterized by their yolk platelet compositions and movement during egg inversion. It is found that during egg inversion the yolk compartments shift minor cytoplasmic compartments which line the egg cortex. Those yolk mass shifts occurred only after the inverted egg was activated. The direction of shift of the major yolk components, rather than the sperm entrance site, determines the dorsal/ventral polarity of the inverted egg. Among different spawnings the rate of shift varied. Eggs that displayed the fastest rate of shift exhibited the highest frequency of developmental abnormalities during organogenesis. Interpretation of novel observations on cytoplasmic organization provide criticism of some earlier models. A new density compartment model is presented as a coherent way to view the organization of the egg cytoplasm and the development of bilateral symmetry.

Egg hatching response to a range of ultraviolet-B (UV-B) radiation doses for four predatory mites and the herbivorous spider mite Tetranychus urticae.

PubMed

Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A

2017-01-01

Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.

Do Uniparental Sanderlings Calidris alba Increase Egg Heat Input to Compensate for Low Nest Attentiveness?

PubMed Central

Reneerkens, Jeroen; Grond, Kirsten; Schekkerman, Hans; Tulp, Ingrid; Piersma, Theunis

2011-01-01

Birds breeding in cold environments regularly have to interrupt incubation to forage, causing a trade-off between two mutually exclusive behaviours. Earlier studies showed that uniparental Arctic sandpipers overall spend less time incubating their eggs than biparental species, but interspecific differences in size and ecology were potential confounding factors. This study reports on a within-species comparison of breeding schedules and metal egg temperatures in uni- and biparental sanderlings (Calidris alba) in Northeast Greenland in relation to ambient temperature. We recorded incubation schedules with nest temperature loggers in 34 sanderling clutches (13 uniparentals, 21 biparentals). The temperature of a metal egg placed within the clutch of 17 incubating birds (6 uniparentals, 9 biparentals) was measured as an indicator of the heat put into eggs. Recess frequency, recess duration and total recess time were higher in uniparentals than in biparentals and positively correlated with ambient temperatures in uniparentals only. Uniparental sanderlings maintained significantly higher metal egg temperatures during incubation than biparentals (1.4°C difference on average). Our results suggest that uniparental sanderlings compensate for the lower nest attendance, which may prolong the duration of the incubation period and negatively affect the condition of the hatchlings, by maintaining a higher heat flux into the eggs. PMID:21347377

Development of a PCR Assay for Diagnosing Trematode (Opisthorchis and Haplorchis) Infections in Human Stools

PubMed Central

Kanda, Seiji; Laimanivong, Sakhone; Shimono, Takaki; Darcy, Andrew Waleluma; Phyaluanglath, Amphay; Mishima, Nobuyuki; Nishiyama, Toshimasa

2017-01-01

We developed a combined conventional polymerase chain reaction (PCR) and real-time PCR (qPCR)-based assay for detecting and discriminating between Opisthorchis viverrini and Haplorchis taichui parasite infections. The first PCR amplifies the mitochondrial cytochrome c oxidase subunit I (COI) genes of parasites, and differential diagnosis is achieved by performing qPCR with specific primers and SYBR Green I. The detection limit of the assay was found to be 2.0 × 102 plasmid copies in a test in which a stool sample was spiked with a single egg, which is equivalent to 5 eggs per gram (EPG). The testing of 34 clinical stool samples that had been demonstrated to contain “Opisthorchis-like” eggs by microscopy showed that the novel assay exhibited a sensitivity of 100% for “Opisthorchis-like” parasitic infections, and 71% and 91% of these samples were found to be infected with O. viverrini and H. taichui, respectively. A further four parasitic infections were diagnosed in the 16 negative samples, and the microscopic findings of these samples were confirmed to be false negatives by sequencing analysis. The assay also displayed high specificity during the testing of 10 samples containing other common parasites. The fact that our qPCR SYBR Green I–based assay detected submicroscopic traces of parasitic DNA and was able to differentiate between parasites that produce eggs with similar morphologies indicates that it has a good potential for development of diagnostic application to use in areas where multiple parasites coexist. PMID:27821695

21 CFR 160.145 - Dried egg whites.

Code of Federal Regulations, 2010 CFR

2010-04-01

... whites. The quantity used and the time of reaction are sufficient to substantially reduce the glucose... time of reaction are sufficient to substantially reduce the glucose content. (ii) Bacterial procedure. The liquid egg whites are subjected to the action of a culture of glucose-fermenting bacteria either...

Effect of storage duration on the rheological properties of goose liquid egg products and eggshell membranes.

PubMed

Kumbar, V; Nedomova, S; Trnka, J; Buchar, J; Pytel, R

2016-07-01

In practice, goose eggs are increasingly used and, therefore, the rheological properties have to be known for processing. The eggs of geese (Landes Goose, Anser anser f. domestica) were stored for one, 2, 3, 4, 6, and 8 wk at a constant temperature 4°C. First of all, the egg quality parameters were described in terms of egg weight, egg weight loss, egg shape index, yolk height, albumen height, yolk index, albumen index, and Haugh units. In the next step the rheological behavior of liquid egg products (egg yolk, albumen, and whole liquid egg) was studied using a concentric cylinder viscometer. Flow curves of all liquid egg products exhibited non-Newtonian shear thinning behavior. This behavior can be described using the Herschel-Bulkley model and for technical application using the Ostwald-de Waele model. The effect of the storage duration on the rheological behavior is different for the different liquid egg products. With the exception of very low shear rates, the viscosity of the egg yolk as well as of the whole liquid egg decreases with storage time. At lower shear rates there is a tendency toward increased albumen viscosity with storage duration. The storage duration also affects the mechanical properties of the eggshell membrane. This effect has been evaluated in terms of the ultimate tensile strength, fracture strain, and fracture toughness. All these parameters increased with the loading rate, but decreased during the egg storage. These mechanical phenomena should be respected, namely in the design of the egg model for the numerical simulation of the egg behavior under different kinds of the mechanical loading. © 2016 Poultry Science Association Inc.

Fatty acid and cholesterol profiles and hypocholesterolemic, atherogenic, and thrombogenic indices of table eggs in the retail market.

PubMed

Attia, Youssef A; Al-Harthi, Mohammed A; Korish, Mohamed A; Shiboob, Mohamed M

2015-10-27

Eggs are an important source of food due to its favorable effects on human health derived from the protein, fats, minerals, vitamins and bioactive components. We studied the effects of source of eggs in the retail market on fatty acids, lipid profiles and antioxidant status in eggs. Eggs from four sources named A, B, C, and D in the retail market were collected to determine fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; antioxidant status (e.g., of malondialdehyde); and total antioxidant capacity in the whole edible parts of eggs (albumen + yolk) and egg yolk. Samples were collected four times and pooled over times to represent 5 and 10 samples per source for determinations of fatty acids and determinations of lipid profiles and antioxidant status, respectively. Fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; presence of malondialdehyde; and total antioxidant capacity in the whole edible parts of eggs and egg yolk showed significant differences (P ≥ 0.05) among different sources of eggs in retail market. Source D showed higher levels of saturated fatty acids (SFA) and linoleic and monounsaturated fatty acid (MUFA)/polyunsaturated fatty acid (PUFA) ratio but lower levels of MUFA and linolenic, arachidonic, eicosapentaeonic (EPA), decohexaenoic (DHA), and total ω9 fatty acids and lower unsaturated fatty acids (UFA)/SFA ratio. Similar trend was shown in fatty acids profiles of the whole edible parts of eggs. On the other hand, total cholesterol, low density lipoprotein (LDL), LDL/high density lipoprotein (HDL) ratio, and atherogenic and thrombogenic indices and total antioxidant capacity of source D were significantly higher than those of other source, but levels of hypocholesterolemic index, and malondialdehyde levels were lower for source D. Eggs in the retail market in Jeddah city, Saudi Arabia, from May to August 2015 showed a different pattern of fatty acid and cholesterol profiles; hypocholesterolemic, atherogenic, and thrombogenic indices; and antioxidant status, which might reflect the nutritional and husbandry practice of laying hens. This can affect the nutritional values of eggs, and hence, customer benefits, suggesting the need for standardization and quality control based on nutrient index values.

Eggshell permeability: a standard technique for determining interspecific rates of water vapor conductance.

PubMed

Portugal, Steven J; Maurer, Golo; Cassey, Phillip

2010-01-01

Typically, eggshell water vapor conductance is measured on whole eggs, freshly collected at the commencement of a study. At times, however, it may not be possible to obtain whole fresh eggs but rather egg fragments or previously blown eggs. Here we evaluate and describe in detail a technique for modern laboratory analysis of eggshell conductance that uses fragments from fresh and museum eggs to determine eggshell water vapor conductance. We used fresh unincubated eggs of domesticated chickens (Gallus gallus domesticus), ducks (Anas platyrhynchos domesticus), and guinea fowl (Numida meleagris) to investigate the reliability, validity, and repeatability of the technique. To assess the suitability of museum samples, museum and freshly collected black-headed gull eggs (Larus ridibundus) were used. Fragments were cut out of the eggshell from the blunt end (B), equator (E), and pointy end (P). Eggshell fragments were glued to the top of a 0.25-mL micro test tube (Eppendorf) filled with 200 μL of distilled water and placed in a desiccator at 25°C. Eppendorfs were weighed three times at 24-h intervals, and mass loss was assumed to be a result of water evaporation. We report the following results: (1) mass loss between weighing sessions was highly repeatable and consistent in all species; (2) the majority of intraspecific variability in eggshell water vapor conductance between different eggs of the same species was explained through the differences in water vapor conductance between the three eggshell parts of the same egg (B, E, and P); (3) the technique was sensitive enough to detect significant differences between the three domestic species; (4) there was no overall significant difference between water vapor conductance of museum and fresh black-headed gull eggs; (5) there was no significant difference in water vapor conductance for egg fragments taken from the same egg both between different trials and within the same trial. We conclude, therefore, that this technique is an effective way of measuring interspecific water vapor conductance from eggshell fragments and that museum eggs are a suitable resource for such work.

Albendazole treatment in laying hens: Egg residues and its effects on fertility and hatchability.

PubMed

Moreno, Laura; Bistoletti, Mariana; Fernández, Hector; Cantón, Lucila; Ceballos, Laura; Cantón, Candela; Lanusse, Carlos; Álvarez, Luis I

2018-06-12

This work characterized the egg residual concentrations of albendazole (ABZ) and its sulphoxide (ABZSO) and sulphone (ABZSO 2 ) metabolites and evaluated their effect on egg fertility and hatchability after ABZ treatments to laying hens. Seventy hens were allocated in groups: Group-1 was the control without treatment; Group-2 received a single ABZ oral dose (10 mg/kg); Group-3, -4 and -5 were treated with ABZ in medicated feed over 7 days at 10, 40, or 80 mg kg -1  day -1 , respectively. Eggs were analyzed to determine the ABZ/metabolite level by HPLC or subjected to incubation to evaluate the fertility and hatchability. Only ABZSO and ABZSO 2 metabolites were quantified in egg after ABZ single oral administration with maximum concentrations of 0.47 ± 0.08 and 0.30 ± 0.07 μg/ml, respectively. ABZ and its metabolites were found in eggs after 7-day ABZ treatments. The egg residue exposure estimated as AUCs (areas under the concentration vs. time curve) were 100.5 (ABZ), 56.3 (ABZSO) and 141.3 μg hr g -1 (ABZSO 2 ). ABZ administration did not affect the egg fertility at any dosages. Egg hatchability was not affected by ABZ treatment at 10 mg/kg in medicated feed, but it decreased when the dose was 4-8 times higher. These results should be considered when ABZ is used for deworming laying hens. © 2018 John Wiley & Sons Ltd.

A chitin-like component in Aedes aegypti eggshells, eggs and ovaries.

PubMed

Moreira, Mônica F; Dos Santos, Amanda S; Marotta, Humberto R; Mansur, Juliana F; Ramos, Isabela B; Machado, Ednildo A; Souza, Gustavo H M F; Eberlin, Marcos N; Kaiser, Carlos R; Kramer, Karl J; Muthukrishnan, Subbaratnam; Vasconcellos, Ana Maria H

2007-12-01

An insoluble white substance was prepared from extracts of eggshells of Aedes aegypti, the yellow fever mosquito and dengue vector. Its infrared and proton NMR spectra were similar to that of standard commercial chitin. This putative chitin-like material, also obtained from ovaries, newly laid and dark eggs, was hydrolyzed in acid and a major product was identified by HPLC to be glucosamine. The eggshell acid hydrolysate was also analyzed by ESI-MS and an ion identical to a glucosamine monoprotonated species was detected. The presence of chitin was also analyzed during different developmental stages of the ovary using a fluorescent microscopy technique and probes specific for chitin. The results showed that a chitin-like material accumulates in oocytes during oogenesis. Streptomyces griseus chitinase pre-treatment of oocytes greatly reduced the chitin-derived fluorescence. Chitinase activity was detected in newborn larvae and eggs prior to hatching. Feeding experiments indicated that the chitin synthesis inhibitor lufenuron inhibited chitin synthesis, either when mosquitoes were allowed to feed directly on lufenuron-treated chickens or when an artificial feeding system was used. Lufenuron inhibited egg hatch, larval development and reduced mosquito viability. These data demonstrate for the first time that (1) a chitin-like material is present in A. aegypti eggs, ovaries and eggshells; (2) a chitin synthesis inhibitor can be used to inhibit mosquito oogenesis; and (3) chitin synthesis inhibitors have potential for controlling mosquito populations.

The influence of social structure on brood survival and development in a socially polymorphic ant: insights from a cross-fostering experiment.

PubMed

Purcell, Jessica; Chapuisat, M

2012-11-01

Animal societies vary in the number of breeders per group, which affects many socially and ecologically relevant traits. In several social insect species, including our study species Formica selysi, the presence of either one or multiple reproducing females per colony is generally associated with differences in a suite of traits such as the body size of individuals. However, the proximate mechanisms and ontogenetic processes generating such differences between social structures are poorly known. Here, we cross-fostered eggs originating from single-queen (= monogynous) or multiple-queen (= polygynous) colonies into experimental groups of workers from each social structure to investigate whether differences in offspring survival, development time and body size are shaped by the genotype and/or prefoster maternal effects present in the eggs, or by the social origin of the rearing workers. Eggs produced by polygynous queens were more likely to survive to adulthood than eggs from monogynous queens, regardless of the social origin of the rearing workers. However, brood from monogynous queens grew faster than brood from polygynous queens. The social origin of the rearing workers influenced the probability of brood survival, with workers from monogynous colonies rearing more brood to adulthood than workers from polygynous colonies. The social origin of eggs or rearing workers had no significant effect on the head size of the resulting workers in our standardized laboratory conditions. Overall, the social backgrounds of the parents and of the rearing workers appear to shape distinct survival and developmental traits of ant brood. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.