Nest construction by a ground-nesting bird represents a potential trade-off between egg crypticity and thermoregulation.

PubMed

Mayer, Paul M; Smith, Levica M; Ford, Robert G; Watterson, Dustin C; McCutchen, Marshall D; Ryan, Mark R

2009-04-01

Predation selects against conspicuous colors in bird eggs and nests, while thermoregulatory constraints select for nest-building behavior that regulates incubation temperatures. We present results that suggest a trade-off between nest crypticity and thermoregulation of eggs based on selection of nest materials by piping plovers (Charadrius melodus), a ground-nesting bird that constructs simple, pebble-lined nests highly vulnerable to predators and exposed to temperature extremes. Piping plovers selected pebbles that were whiter and appeared closer in color to eggs than randomly available pebbles, suggesting a crypsis function. However, nests that were more contrasting in color to surrounding substrates were at greater risk of predation, suggesting an alternate strategy driving selection of white rocks. Near-infrared reflectance of nest pebbles was higher than randomly available pebbles, indicating a direct physical mechanism for heat control through pebble selection. Artificial nests constructed of randomly available pebbles heated more quickly and conferred heat to model eggs, causing eggs to heat more rapidly than in nests constructed from piping plover nest pebbles. Thermal models and field data indicated that temperatures inside nests may remain up to 2-6 degrees C cooler than surrounding substrates. Thermal models indicated that nests heat especially rapidly if not incubated, suggesting that nest construction behavior may serve to keep eggs cooler during the unattended laying period. Thus, pebble selection suggests a potential trade-off between maximizing heat reflectance to improve egg microclimate and minimizing conspicuous contrast of nests with the surrounding substrate to conceal eggs from predators. Nest construction behavior that employs light-colored, thermally reflective materials may represent an evolutionary response by birds and other egg-laying organisms to egg predation and heat stress.

Colonization of reproductive organs and internal contamination of eggs after experimental infection of laying hens with Salmonella heidelberg and Salmonella enteritidis.

PubMed

Gast, Richard K; Guard-Bouldin, Jean; Holt, Peter S

2004-12-01

Internal contamination of eggs laid by hens infected with Salmonella enteritidis has been a prominent international public health issue since the mid-1980s. Considerable resources have been committed to detecting and controlling S. enteritidis infections in commercial laying flocks. Recently, the Centers for Disease Control and Prevention also reported a significant association between eggs or egg-containing foods and S. heidelberg infections in humans. The present study sought to determine whether several S. heidelberg isolates obtained from egg-associated human disease outbreaks were able to colonize reproductive tissues and be deposited inside eggs laid by experimentally infected hens in a manner similar to the previously documented behavior of S. enteritidis. In two trials, groups of laying hens were orally inoculated with large doses of four S. heidelberg strains and an S. enteritidis strain that consistently caused egg contamination in previous studies. All five Salmonella strains (of both serotypes) colonized the intestinal tracts and invaded the livers, spleens, ovaries, and oviducts of inoculated hens, with no significant differences observed between the strains for any of these parameters. All four S. heidelberg strains were recovered from the interior liquid contents of eggs laid by infected hens, although at lower frequencies (between 1.1% and 4.5%) than the S. enteritidis strain (7.0%).

G protein-coupled receptor kinase-2 (GRK-2) regulates serotonin metabolism through the monoamine oxidase AMX-2 in Caenorhabditis elegans.

PubMed

Wang, Jianjun; Luo, Jiansong; Aryal, Dipendra K; Wetsel, William C; Nass, Richard; Benovic, Jeffrey L

2017-04-07

G protein-coupled receptors (GPCRs) regulate many animal behaviors. GPCR signaling is mediated by agonist-promoted interactions of GPCRs with heterotrimeric G proteins, GPCR kinases (GRKs), and arrestins. To further elucidate the role of GRKs in regulating GPCR-mediated behaviors, we utilized the genetic model system Caenorhabditis elegans Our studies demonstrate that grk-2 loss-of-function strains are egg laying-defective and contain low levels of serotonin (5-HT) and high levels of the 5-HT metabolite 5-hydroxyindole acetic acid (5-HIAA). The egg laying defect could be rescued by the expression of wild type but not by catalytically inactive grk-2 or by the selective expression of grk-2 in hermaphrodite-specific neurons. The addition of 5-HT or inhibition of 5-HT metabolism also rescued the egg laying defect. Furthermore, we demonstrate that AMX-2 is the primary monoamine oxidase that metabolizes 5-HT in C. elegans , and we also found that grk-2 loss-of-function strains have abnormally high levels of AMX-2 compared with wild-type nematodes. Interestingly, GRK-2 was also found to interact with and promote the phosphorylation of AMX-2. Additional studies reveal that 5-HIAA functions to inhibit egg laying in a manner dependent on the 5-HT receptor SER-1 and the G protein GOA-1. These results demonstrate that GRK-2 modulates 5-HT metabolism by regulating AMX-2 function and that 5-HIAA may function in the SER-1 signaling pathway. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

G protein-coupled receptor kinase-2 (GRK-2) regulates serotonin metabolism through the monoamine oxidase AMX-2 in Caenorhabditis elegans

PubMed Central

Wang, Jianjun; Luo, Jiansong; Aryal, Dipendra K.; Wetsel, William C.; Nass, Richard; Benovic, Jeffrey L.

2017-01-01

G protein-coupled receptors (GPCRs) regulate many animal behaviors. GPCR signaling is mediated by agonist-promoted interactions of GPCRs with heterotrimeric G proteins, GPCR kinases (GRKs), and arrestins. To further elucidate the role of GRKs in regulating GPCR-mediated behaviors, we utilized the genetic model system Caenorhabditis elegans. Our studies demonstrate that grk-2 loss-of-function strains are egg laying-defective and contain low levels of serotonin (5-HT) and high levels of the 5-HT metabolite 5-hydroxyindole acetic acid (5-HIAA). The egg laying defect could be rescued by the expression of wild type but not by catalytically inactive grk-2 or by the selective expression of grk-2 in hermaphrodite-specific neurons. The addition of 5-HT or inhibition of 5-HT metabolism also rescued the egg laying defect. Furthermore, we demonstrate that AMX-2 is the primary monoamine oxidase that metabolizes 5-HT in C. elegans, and we also found that grk-2 loss-of-function strains have abnormally high levels of AMX-2 compared with wild-type nematodes. Interestingly, GRK-2 was also found to interact with and promote the phosphorylation of AMX-2. Additional studies reveal that 5-HIAA functions to inhibit egg laying in a manner dependent on the 5-HT receptor SER-1 and the G protein GOA-1. These results demonstrate that GRK-2 modulates 5-HT metabolism by regulating AMX-2 function and that 5-HIAA may function in the SER-1 signaling pathway. PMID:28213524

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.

A simple rule reduces costs of extragroup parasitism in a communally breeding bird.

PubMed

Riehl, Christina

2010-10-26

How do cooperatively breeding groups resist invasion by parasitic "cheaters," which dump their eggs in the communal nest but provide no parental care [1,2]? Here I show that Greater Anis (Crotophaga major), Neotropical cuckoos that nest in social groups containing several breeding females [3], use a simple rule based on the timing of laying to recognize and reject eggs laid by extragroup parasites. I experimentally confirmed that Greater Anis cannot recognize parasitic eggs based on the appearance of host egg phenotypes or on the number of eggs in the clutch. However, they can discriminate between freshly laid eggs and those that have already been incubated, and they accordingly eject asynchronous eggs. This mechanism is reliable in naturally parasitized nests, because group members typically lay their eggs in tight synchrony, whereas the majority of parasitic eggs are laid several days later. Rejection of asynchronous eggs therefore provides a rare empirical example of a complex, group-level behavior that arises through relatively simple "rules of thumb" without requiring advanced cognitive mechanisms such as learning, counting, or individual recognition. Copyright © 2010 Elsevier Ltd. All rights reserved.

Dietary Supplementation with Chromium Picolinate Influences Serum Glucose and Immune Response of Brown-Egg Laying Hens.

PubMed

Zhang, Shumin; Sun, Xiaoming; Liao, Xiudong; Lu, Lin; Zhang, Liyang; Ma, Qiugang; Luo, Xugang

2018-01-29

To investigate the effect of chromium picolinate (CrPic) on egg production performance, egg quality, blood indices, and immune function of laying hens, 270 23-week-old Beijing Red brown-egg laying hens were randomly assigned to one of three treatments with six replicates of 15 birds per replicate for each treatment in a completely randomized design. Laying hens were fed a Cr-unsupplemented corn-soybean meal basal diet (control, containing 0.45 mg Cr/kg by analysis) or the basal diet supplemented with 0.4 or 0.6 mg Cr/kg from CrPic for 10 weeks. Laying hens fed diets supplemented with CrPic had a lower (P < 0.05) serum glucose (GLU) concentration and higher (P < 0.03) serum antibody titer against Newcastle disease than those fed the control diet at 33 weeks of age. However, supplemental CrPic had no effect (P > 0.05) on egg production and egg quality of brown-egg laying hens from 24 to 33 weeks of age. The results from this study indicated that supplemental CrPic decreased serum GLU and enhanced the immune function of brown-egg laying hens.

Genetic architecture underlying convergent evolution of egg-laying behavior in a seed-feeding beetle.

PubMed

Fox, Charles W; Wagner, James D; Cline, Sara; Thomas, Frances Ann; Messina, Frank J

2009-05-01

Independent populations subjected to similar environments often exhibit convergent evolution. An unresolved question is the frequency with which such convergence reflects parallel genetic mechanisms. We examined the convergent evolution of egg-laying behavior in the seed-feeding beetle Callosobruchus maculatus. Females avoid ovipositing on seeds bearing conspecific eggs, but the degree of host discrimination varies among geographic populations. In a previous experiment, replicate lines switched from a small host to a large one evolved reduced discrimination after 40 generations. We used line crosses to determine the genetic architecture underlying this rapid response. The most parsimonious genetic models included dominance and/or epistasis for all crosses. The genetic architecture underlying reduced discrimination in two lines was not significantly different from the architecture underlying differences between geographic populations, but the architecture underlying the divergence of a third line differed from all others. We conclude that convergence of this complex trait may in some cases involve parallel genetic mechanisms.

Shaking Youngsters and Shaken Adults: Female Beetles Eavesdrop on Larval Seed Vibrations to Make Egg-Laying Decisions

PubMed Central

Guedes, Raul Narciso C.; Yack, Jayne E.

2016-01-01

Egg-laying decisions are critical for insects, and particularly those competing for limited resources. Sensory information used by females to mediate egg-laying decisions has been reported to be primarily chemical, but the role of vibration has received little attention. We tested the hypothesis that vibrational cues produced by feeding larvae occupying a seed influences egg-laying decisions amongst female cowpea beetles. This hypothesis is supported by three lines of evidence using two strains of the cowpea beetle (Callosobruchus maculatus), an Indian strain with choosy females and aggressively competing larvae and a Brazilian strain with less choosy females and larvae exhibiting an “accommodating” type of competition. First, in free-choice bioassays of seed selection, choosy Indian females selected control seeds (free of eggs, larvae, or egg-laying marker) over seeds with live larvae (free of eggs and egg-laying marker), but did not discriminate between control seeds and those with dead larvae. In contrast, less choosy Brazilian females showed no preference for seeds containing live or dead larvae over controls. Second, laser-doppler vibrometer recordings confirmed that larvae feeding inside seeds generate vibrations that are available to the female during egg-laying decisions. Third, during dichotomous choice experiments where artificial vibrations approximating those produced by feeding larvae were played back during seed selection, Indian females preferred immobile control seeds over vibrating seeds, but Brazilian females showed no preference. These results support the hypothesis that females use larval vibrations in their egg-laying decisions; whether these vibrations are passive cues exploited by the female, or active signals that ‘steer’ the behaviour of the female is unknown. We propose that vibration cues and signals could be important for host selection in insects, particularly those laying on substrates where visual or chemical cues may be unreliable. This seems to be the case with females of the cowpea beetle since visual cues are not important and chemical egg-marking does not last more than two weeks, allowing vibration cues to improve discrimination of egg-laying substrate particularly by choosy females. PMID:26913508

Social regulation of maternal traits in nest-founding bumble bee (Bombus terrestris) queens.

PubMed

Woodard, S Hollis; Bloch, Guy; Band, Mark R; Robinson, Gene E

2013-09-15

During the nest-founding phase of the bumble bee colony cycle, queens undergo striking changes in maternal care behavior. Early in the founding phase, prior to the emergence of workers in the nest, queens are reproductive and also provision and feed their offspring. However, later in the founding phase, queens reduce their feeding of larvae and become specialized on reproduction. This transition is synchronized with the emergence of workers in the colony, who assume the task of feeding their siblings. Using a social manipulation experiment with the bumble bee Bombus terrestris, we tested the hypothesis that workers regulate the transition from feeding brood to specialization on reproduction in nest-founding bumble bee queens. Consistent with this hypothesis, we found that early-stage nest-founding queens with workers prematurely added to their nests reduce their brood-feeding behavior and increase egg laying, and likewise, late-stage nest-founding queens increase their brood-feeding behavior and decrease egg-laying when workers are removed from their nests. Further, brood-feeding and egg-laying behaviors were negatively correlated. We used Agilent microarrays designed from B. terrestris brain expressed sequenced tags (ESTs) to explore a second hypothesis, that workers alter brain gene expression in nest-founding queens. We found evidence that brain gene expression in nest-founding queens is altered by the presence of workers, with the effect being much stronger in late-stage founding queens. This study provides new insights into how the transition from feeding brood to specialization on reproduction in queen bumble bees is regulated during the nest initiation phase of the colony cycle.

Do Bumble Bee, Bombus impatiens, Queens Signal their Reproductive and Mating Status to their Workers?

PubMed

Amsalem, Etya; Padilla, Mario; Schreiber, Paul M; Altman, Naomi S; Hefetz, Abraham; Grozinger, Christina M

2017-06-01

Reproduction in social insect societies reflects a delicate balance between cooperation and conflict over offspring production, and worker reproduction is widespread even in species showing strong reproductive skew in favor of the queen. To navigate these conflicts, workers are predicted to develop the means to estimate the queen's fecundity - potentially through behavioral and/or chemical cues - and to adjust their reproduction to maximize their fitness. Here, we introduced bumble bee, Bombus impatiens, workers to queens of different mating and reproductive status and examined worker reproduction and expression levels of two genes which were previously shown to be sensitive to the presence of the queen, vitellogenin and Krüppel-homolog 1. We further explored whether the queen's chemical secretion alone is sufficient to regulate worker reproduction, aggression and gene expression. We found that worker ovary activation was inhibited only in the presence of egg-laying queens, regardless of their mating status. Workers reared in the presence of newly-mated queens showed intermediate vitellogenin expression levels relative to workers reared with mated egg-laying and virgin queens. However, none of the whole-body chemical extracts of any of the queen treatment groups affected ovary activation, aggressive behavior, or gene expression in workers. Our findings indicate that only the presence of a freely-behaving, egg-laying queen can fully inhibit worker reproduction. It remains to be determined if workers detect differences in queen mating status and fecundity through differences in the queens' behavior alone or through the queen's behavior in concert with fertility signals.

Laying traits and underlying transcripts, expressed in the hypothalamus and pituitary gland, that were associated with egg production variability in chickens.

PubMed

Chen, Chih-Feng; Shiue, Yow-Ling; Yen, Cheng-Ju; Tang, Pin-Chi; Chang, Hui-Chiu; Lee, Yen-Pai

2007-12-01

The objective was to characterize the potential laying traits and underlying transcripts expressed in the hypothalamus and pituitary gland that were associated with egg production variability in five genetic stocks of chickens: two commercial lines, Red- (n=12) and Black-feather (n=14) Taiwan country chickens (TCCs); two selected lines of TCCs, B (high body weight/comb size; n=17) and L2 (high-egg production; n=14); and a commercial single comb White Leghorn (WL; n=17). Six laying traits, age at first egg, clutch length, pause length, oviposition lag within clutch, follicle rapid growth period, and rate of yolk accumulation were measured. The significance of differential values among five chicken stocks and correlation coefficients between laying traits and number of eggs to 50 weeks of age or laying rate after first egg, and the expression level of 33 transcripts were determined. Longer clutch length and shorter oviposition lag within clutch contributed to a higher number of eggs to 50 weeks of age or laying rate after first egg in L2 (P<0.05) and WL strains (P<0.05). However, their rate of yolk accumulation (P<0.05) and follicle rapid growth period (P<0.05) were different, indicating the accumulation of different alleles after long-term, independent selection. Across all five strains, numbers of eggs to 50 weeks of age were positive correlated with average clutch length (P<0.05) as well as the rate of yolk accumulation (P<0.05). Expressions of PLAG1, STMN2, PGDS, PARK7, ANP32A, PCDHA@, SCG2, BDH and SAR1A transcripts contributed to number of eggs to 50 weeks of age (P<0.05) or laying rate after first egg (P<0.05). Analysis of correlation coefficients indicated that PLAG1 additionally played roles in decreasing average pause length. Two transcripts, PRL and GARNL1, specifically contributed to number of eggs to 50 weeks of age or laying rate after first egg by reducing oviposition lag within clutch (P<0.05) and/or increasing average clutch length (P<0.05), respectively. Expression level of NCAM1, contributed to laying rate after first egg by association with a shorter oviposition lag within clutch (P<0.05). The current study attributed egg production phenotype in five strains into several laying traits; correlations between these traits and expression levels of underlying transcripts expressed in the hypothalamus and pituitary gland were also established.

Age-Dependent Effects of Oral Infection with Dengue Virus on Aedes aegypti (Diptera: Culicidae) Feeding Behavior, Survival, Oviposition Success and Fecundity

PubMed Central

Sylvestre, Gabriel; Gandini, Mariana; Maciel-de-Freitas, Rafael

2013-01-01

Background Aedes aegypti is the main vector of dengue, a disease that is increasing its geographical range as well as incidence rates. Despite its public health importance, the effect of dengue virus (DENV) on some mosquito traits remains unknown. Here, we investigated the impact of DENV-2 infection on the feeding behavior, survival, oviposition success and fecundity of Ae. aegypti females. Methods/Principal Findings After orally-challenging Ae. aegypti females with a DENV-2 strain using a membrane feeder, we monitored the feeding behavior, survival, oviposition success and fecundity throughout the mosquito lifespan. We observed an age-dependent cost of DENV infection on mosquito feeding behavior and fecundity. Infected individuals took more time to ingest blood from anesthetized mice in the 2nd and 3rd weeks post-infection, and also longer overall blood-feeding times in the 3rd week post-infection, when females were around 20 days old. Often, infected Ae. aegypti females did not lay eggs and when they were laid, smaller number of eggs were laid compared to uninfected controls. A reduction in the number of eggs laid per female was evident starting on the 3rd week post-infection. DENV-2 negatively affected mosquito lifespan, since overall the longevity of infected females was halved compared to that of the uninfected control group. Conclusions The DENV-2 strain tested significantly affected Ae. aegypti traits directly correlated with vectorial capacity or mosquito population density, such as feeding behavior, survival, fecundity and oviposition success. Infected mosquitoes spent more time ingesting blood, had reduced lifespan, laid eggs less frequently, and when they did lay eggs, the clutches were smaller than uninfected mosquitoes. PMID:23555838

[Spatial distribution pattern of Pontania dolichura larvae and sampling technique].

PubMed

Zhang, Feng; Chen, Zhijie; Zhang, Shulian; Zhao, Huiyan

2006-03-01

In this paper, the spatial distribution pattern of Pontania dolichura larvae was analyzed with Taylor's power law, Iwao's distribution function, and six aggregation indexes. The results showed that the spatial distribution pattern of P. dolichura larvae was of aggregated, and the basic component of the distribution was individual colony, with the aggregation intensity increased with density. On branches, the aggregation was caused by the adult behavior of laying eggs and the spatial position of leaves, while on leaves, the aggregation was caused by the spatial position of news leaves in spring when m < 2.37, and by the spatial position of news leaves in spring and the behavior of eclosion and laying eggs when m > 2.37. By using the parameters alpha and beta in Iwao's m * -m regression equation, the optimal and sequential sampling numbers were determined.

Effects of environmental temperature on oviposition behavior in three blow fly species of forensic importance.

PubMed

Ody, Helen; Bulling, Mark T; Barnes, Kate M

2017-06-01

A number of factors are known to affect blow fly behavior with respect to oviposition. Current research indicates that temperature is the most significant factor. However temperature thresholds for oviposition in forensically important blow flies have not been well studied. Here, the oviposition behavior of three species of forensically important blow fly species (Calliphora vicina, Calliphora vomitoria and Lucilia sericata,) was studied under controlled laboratory conditions over a range of temperatures (10-40°C). Lower temperature thresholds for oviposition of 16°C and 17.5°C were established for C. vomitoria and L. sericata respectively, whilst C. vicina continued to lay eggs at 10°C. C. vomitoria and L. sericata both continued to lay eggs at 40°C, whilst the highest temperature at which oviposition occurred in C. vicina was 35°C. Within these thresholds there was considerable variation in the number of surviving pupae, with a general pattern of a single peak within the range of temperatures at which eggs were laid, but with the pattern being much less distinct for L. sericata. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Effect of selenium-enriched probiotics on laying performance, egg quality, egg selenium content, and egg glutathione peroxidase activity.

PubMed

Pan, Cuiling; Zhao, Yuxin; Liao, Shengfa F; Chen, Fu; Qin, Shunyi; Wu, Xianshi; Zhou, Hong; Huang, Kehe

2011-11-09

A 35-day experiment was conducted to evaluate the effect of selenium-enriched probiotics (SP) on laying performance, egg quality, egg selenium (Se) content, and egg glutathione peroxidase (GPX) activity. Five hundred 58-week-old Rohman laying hens were randomly allotted to 5 dietary treatments of 100 each. Each treatment had 5 replicates, and each replicate had 5 cages with 4 hens per cage. The SP was supplemented to a corn-soybean-meal basal diet at 3 different levels that supplied total Se at 0.2, 0.5, and 1.0 mg/kg. The basal diet served as a blank control, while the basal diet with supplemental probiotics served as a probiotics control. The results showed that dietary SP supplementation not only increased (p < 0.05) the rate of egg laying, day egg weight, mean egg weight, egg Se content, and egg GPX activity but also decreased (p < 0.05) the feed:egg ratio and egg cholesterol content. The egg Se content was gradually increased (p < 0.05) along with the increasing level of dietary Se. The SP supplementation also slowed down (p < 0.05) the drop of Haugh units (HU) of eggs stored at room temperature. The egg GPX activity had a positive correlation (p < 0.01) with egg Se content and a negative correlation (p < 0.01) with egg HU drop. These results suggested that Se contents, GPX activity, and HU of eggs were affected by the dietary Se level, whereas the egg-laying performance and egg cholesterol content were affected by the dietary probiotics. It was concluded that this SP is an effective feed additive that combines the organic Se benefit for hen and human health with the probiotics benefit for laying hen production performance. It was also suggested that the eggs from hens fed this SP can serve as a nutraceutical food with high Se and low cholesterol contents for both healthy people and patients with hyperlipidemia, fatty liver, or cardiovascular disease.

CNP-1 (ARRD-17), a novel substrate of calcineurin, is critical for modulation of egg-laying and locomotion in response to food and lysine sensation in Caenorhabditis elegans.

PubMed

Jee, Changhoon; Choi, Tae-Woo; Kalichamy, Karunambigai; Yee, Jong Zin; Song, Hyun-Ok; Ji, Yon Ju; Lee, Jungsoo; Lee, Jin Il; L'Etoile, Noelle D; Ahnn, Joohong; Lee, Sun-Kyung

2012-03-30

Calcineurin is a Ca(2+)/calmodulin-dependent protein phosphatase involved in calcium signaling pathways. In Caenorhabditis elegans, the loss of calcineurin activity causes pleiotropic defects including hyperadaptation of sensory neurons, hypersensation to thermal difference and hyper-egg-laying when worms are refed after starvation. In this study, we report on arrd-17 as calcineurin-interacting protein-1 (cnp-1), which is a novel molecular target of calcineurin. CNP-1 interacts with the catalytic domain of the C. elegans calcineurin A subunit, TAX-6, in a yeast two-hybrid assay and is dephosphorylated by TAX-6 in vitro. cnp-1 is expressed in ASK, ADL, ASH and ASJ sensory neurons as TAX-6. It acts downstream of tax-6 in regulation of locomotion and egg-laying after starvation, ASH sensory neuron adaptation and lysine chemotaxis, that is known to be mediated by ASK neurons. Altogether, our biochemical and genetic evidence indicates that CNP-1 is a direct target of calcineurin and required in stimulated egg-laying and locomotion after starvation, adaptation to hyperosmolarity and attraction to lysine, which is modulated by calcineurin. We suggest that the phosphorylation status of CNP-1 plays an important role in regulation of refed stimulating behaviors after starvation and attraction to amino acid, which provides valuable nutritious information. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

H2O2-Sensitive Isoforms of Drosophila melanogaster TRPA1 Act in Bitter-Sensing Gustatory Neurons to Promote Avoidance of UV During Egg-Laying

PubMed Central

Guntur, Ananya R.; Gou, Bin; Gu, Pengyu; He, Ruo; Stern, Ulrich; Xiang, Yang; Yang, Chung-Hui

2017-01-01

The evolutionarily conserved TRPA1 channel can sense various stimuli including temperatures and chemical irritants. Recent results have suggested that specific isoforms of Drosophila TRPA1 (dTRPA1) are UV-sensitive and that their UV sensitivity is due to H2O2 sensitivity. However, whether such UV sensitivity served any physiological purposes in animal behavior was unclear. Here, we demonstrate that H2O2-sensitive dTRPA1 isoforms promote avoidance of UV when adult Drosophila females are selecting sites for egg-laying. First, we show that blind/visionless females are still capable of sensing and avoiding UV during egg-laying when intensity of UV is high yet within the range of natural sunlight. Second, we show that such vision-independent UV avoidance is mediated by a group of bitter-sensing neurons on the proboscis that express H2O2-sensitive dTRPA1 isoforms. We show that these bitter-sensing neurons exhibit dTRPA1-dependent UV sensitivity. Importantly, inhibiting activities of these bitter-sensing neurons, reducing their dTRPA1 expression, or reducing their H2O2-sensitivity all significantly reduced blind females’ UV avoidance, whereas selectively restoring a H2O2-sensitive isoform of dTRPA1 in these neurons restored UV avoidance. Lastly, we show that specifically expressing the red-shifted channelrhodopsin CsChrimson in these bitter-sensing neurons promotes egg-laying avoidance of red light, an otherwise neutral cue for egg-laying females. Together, these results demonstrate a physiological role of the UV-sensitive dTRPA1 isoforms, reveal that adult Drosophila possess at least two sensory systems for detecting UV, and uncover an unexpected role of bitter-sensing taste neurons in UV sensing. PMID:27932542

H2O2-Sensitive Isoforms of Drosophila melanogaster TRPA1 Act in Bitter-Sensing Gustatory Neurons to Promote Avoidance of UV During Egg-Laying.

PubMed

Guntur, Ananya R; Gou, Bin; Gu, Pengyu; He, Ruo; Stern, Ulrich; Xiang, Yang; Yang, Chung-Hui

2017-02-01

The evolutionarily conserved TRPA1 channel can sense various stimuli including temperatures and chemical irritants. Recent results have suggested that specific isoforms of Drosophila TRPA1 (dTRPA1) are UV-sensitive and that their UV sensitivity is due to H 2 O 2 sensitivity. However, whether such UV sensitivity served any physiological purposes in animal behavior was unclear. Here, we demonstrate that H 2 O 2 -sensitive dTRPA1 isoforms promote avoidance of UV when adult Drosophila females are selecting sites for egg-laying. First, we show that blind/visionless females are still capable of sensing and avoiding UV during egg-laying when intensity of UV is high yet within the range of natural sunlight. Second, we show that such vision-independent UV avoidance is mediated by a group of bitter-sensing neurons on the proboscis that express H 2 O 2 -sensitive dTRPA1 isoforms. We show that these bitter-sensing neurons exhibit dTRPA1-dependent UV sensitivity. Importantly, inhibiting activities of these bitter-sensing neurons, reducing their dTRPA1 expression, or reducing their H 2 O 2 -sensitivity all significantly reduced blind females' UV avoidance, whereas selectively restoring a H 2 O 2 -sensitive isoform of dTRPA1 in these neurons restored UV avoidance. Lastly, we show that specifically expressing the red-shifted channelrhodopsin CsChrimson in these bitter-sensing neurons promotes egg-laying avoidance of red light, an otherwise neutral cue for egg-laying females. Together, these results demonstrate a physiological role of the UV-sensitive dTRPA1 isoforms, reveal that adult Drosophila possess at least two sensory systems for detecting UV, and uncover an unexpected role of bitter-sensing taste neurons in UV sensing. Copyright © 2017 by the Genetics Society of America.

Effect of macroalgae enriched with microelements on egg quality parameters and mineral content of eggs, eggshell, blood, feathers and droppings.

PubMed

Michalak, I; Chojnacka, K; Dobrzański, Z; Górecki, H; Zielińska, A; Korczyński, M; Opaliński, S

2011-06-01

This study presents results obtained from feeding experiment on laying hens, which were fed with the diet supplemented with two marine macroalgae: Enteromorpha prolifera and Cladophora sp., enriched with microelements [Cu(II), Zn(II), Co(II), Mn(II), Cr(III)]. The applicability of the preparation was tested on five experimental groups of laying hens and one control group. In the control group, microelements were supplemented in the inorganic form, whereas in experimental groups, Cu, Zn, Co, Mn and Cr were replaced by macroalgae enriched with a given microelement ion. During feeding experiment, weight of laying hens, weight of eggs, eggshell thickness and mineral content of blood, feathers, droppings, eggs content (separately yolk and egg white) and eggshell were measured. Also egg number was counted and microclimate (temperature and relative humidity) was monitored. Supplementing bio-metallic feed additives to the diet of laying hens resulted in higher microelement transfer to eggs and enhanced the colour of yolk. It was also found that the presence of Enteromorpha prolifera and Cladophora sp. in laying hens diet influenced advantageously eggs weight, eggshell thickness as well as body weight of hens. On the basis of these results, it could be concluded that Enteromorpha prolifera and Cladophora sp. enriched with microelement ions could be potentially used as mineral feed additives in laying hens feeding. © 2010 Blackwell Verlag GmbH.

Uncoupling clutch size, prolactin, and luteinizing hormone using experimental egg removal.

PubMed

Ryan, Calen P; Dawson, Alistair; Sharp, Peter J; Williams, Tony D

2015-03-01

Clutch size is a key avian fitness and life history trait. A physiological model for clutch size determination (CSD), involving an anti-gonadal effect of prolactin (PRL) via suppression of luteinizing hormone (LH), was proposed over 20 years ago, but has received scant experimental attention since. The few studies looking at a PRL-based mechanistic hypothesis for CSD have been equivocal, but recent experiments utilizing a pharmacological agent to manipulate PRL in the zebra finch (Taeniopygia guttata) found no support for a role of this hormone in clutch size determination. Here, we take a complementary approach by manipulating clutch size through egg removal, examining co-variation in PRL and LH between two breeding attempts, as well as through experimentally-extended laying. Clutch size increased for egg removal females, but not controls, but this was not correlated with changes in PRL or LH. There were also no differences in PRL between egg removal females and controls, nor did PRL levels during early, mid- or late-laying of supra-normal clutches predict clutch size. By uncoupling PRL, LH and clutch size in our study, several key predictions of the PRL-based mechanistic model for CSD were not supported. However, a positive correlation between PRL levels late in laying and days relative to the last egg (clutch completion) provides an alternative explanation for the equivocal results surrounding the conventional PRL-based physiological model for CSD. We suggest that females coordinate PRL-mediated incubation onset with clutch completion to minimize hatching asynchrony and sibling hierarchy, a behavior that is amplified in females laying larger clutches. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of Reserpine on Reproduction and Serotonin Immunoreactivity in the Stable Fly Stomoxys Calcitrans (L.)

USDA-ARS?s Scientific Manuscript database

Biogenic amines are known to play critical roles in key insect behaviors such as feeding and reproduction. This study documents the effects of reserpine on mating and egg-laying behaviors of the stable fly, Stomoxys calcitrans (L.) (Diptera: Muscidae), which is one of the most economically significa...

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.

The effect of perches in cages during pullet rearing and egg laying on hen performance, foot health, and plumage.

PubMed

Hester, P Y; Enneking, S A; Jefferson-Moore, K Y; Einstein, M E; Cheng, H W; Rubin, D A

2013-02-01

Enrichment of pullet cages with perches has not been studied. Our objective was to determine if access to metal perches during all or part of the life cycle of caged White Leghorns affected egg traits, foot health, and feather condition. Treatment 1 represented control chickens that never had access to perches during their life cycle. Treatment 2 hens had perches only during the egg laying phase of the life cycle (17 to 71 wk of age), whereas treatment 3 chickens had perches during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens always had access to perches (0 to 71 wk of age). Comparisons between chickens that always had perches with controls that never had perches showed similar performance relative to egg production, cracked eggs, egg weight, shell weight, % shell, and shell thickness. More dirty eggs occurred in laying cages with perches. Feed usage increased resulting in poorer feed efficiency in hens with perch exposure during the pullet phase with no effect during egg laying. Perches did not affect hyperkeratosis of toes and feet. The back claw at 71 wk of age broke less if hens had prior experience with perches during the pullet phase. In contrast, during egg laying, the back claw at 71 wk of age broke more due to the presence of perches in laying cages. Perches in laying cages resulted in shorter trimmed claws and improved back feather scores, but caused poorer breast and tail feather scores. In conclusion, enriching conventional cages with perches during the entire life cycle resulted in similar hen performance compared with controls. Fewer broken back claws but poorer feed efficiency occurred because of prior experience with perches as pullets. Perch presence during egg laying improved back feather scores with more trimmed nails but caused more dirty eggs, broken back claws, and poorer breast and tail feather scores. Although perches allow chickens to express their natural perching instinct, it was not without causing welfare problems.

Egg laying sequence influences egg mercury concentrations and egg size in three bird species: Implications for contaminant monitoring programs

USGS Publications Warehouse

Ackerman, Joshua T.; Eagles-Smith, Collin A.; Herzog, Mark P.; Yee, Julie L.; Hartman, C. Alex

2016-01-01

Bird eggs are commonly used in contaminant monitoring programs and toxicological risk assessments, but intra-clutch variation and sampling methodology could influence interpretability. We examined the influence of egg laying sequence on egg mercury concentrations and burdens in American avocets, black-necked stilts, and Forster's terns. The average decline in mercury concentrations between the first and last egg laid was 33% for stilts, 22% for terns, and 11% for avocets, and most of this decline occurred between the first and second eggs laid (24% for stilts, 18% for terns, and 9% for avocets). Trends in egg size with egg laying order were inconsistent among species and overall differences in egg volume, mass, length, and width were <3%. We summarized the literature and, among 17 species studied, mercury concentrations generally declined by 16% between the first and second eggs laid. Despite the strong effect of egg laying sequence, most of the variance in egg mercury concentrations still occurred among clutches (75%-91%) rather than within clutches (9%-25%). Using simulations, we determined that to accurately estimate a population's mean egg mercury concentration using only a single random egg from a subset of nests, it would require sampling >60 nests to represent a large population (10% accuracy) or ≥14 nests to represent a small colony that contained <100 nests (20% accuracy).

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.

Constant and changing photoperiods in the laying period for broiler breeders allowed [corrected] normal or accelerated growth during the rearing period.

PubMed

Lewis, P D; Gous, R M

2006-02-01

Broiler breeder pullets were grown on 8-h photoperiods to 2.23 or 2.42 kg of BW at 20 wk, and then transferred abruptly to 11- or 16-h photoperiods. Subsequently, some of the 11-h photoperiod birds were given 15-min increases in day length weekly or a 1-h increase every 4 wk to reach 16 h of light at 54 wk. The birds transferred abruptly to a 16-h photoperiod at 20 wk matured 4 d earlier than 11-h photoperiod birds, required 500 g less feed to reach 50% lay, but, because of a 3% lower rate of lay after peak, produced 5 fewer eggs to 60 wk. However, the number of settable eggs was similar for the 2 groups because the 11-h photoperiod birds laid more eggs on the floor, resulting in more cracked and dirty eggs. The 11-h photoperiod birds converted feed into egg more efficiently, and were 100 g heavier at end of lay. Increasing the photoperiod in 15-min or 1-h increments from 11 to 16 h during the laying cycle depressed egg production. Mean egg weight and mortality were similar for all lighting groups. The heavier BW birds at 20 wk reached maturity 1 d earlier, but used 1 kg more feed to reach maturity, laid 5 fewer total eggs (because of a 3% lower rate of lay after peak), produced 7 more unsettable eggs (because more eggs were laid on the floor), and converted feed into egg less efficiently than did the lighter BW birds. Mean egg weight, BW at 57 wk, and mortality were similar for both groups. There was no significant light x growth interaction for any performance parameter. It is concluded that there is no benefit to egg production from extending the photoperiod to 16 h when broiler breeders are kept in light-proofed housing, especially if they have access to illuminated nest boxes.

Impact of commercial housing systems and nutrient and energy intake on laying hen performance and egg quality parameters1

PubMed Central

Karcher, D. M.; Jones, D. R.; Abdo, Z.; Zhao, Y.; Shepherd, T. A.; Xin, H.

2015-01-01

The US egg industry is exploring alternative housing systems for laying hens. However, limited published research related to cage-free aviary systems and enriched colony cages exists related to production, egg quality, and hen nutrition. The laying hen's nutritional requirements and resulting productivity are well established with the conventional cage system, but diminutive research is available in regards to alternative housing systems. The restrictions exist with limited availability of alternative housing systems in research settings and the considerable expense for increased bird numbers in a replicate due to alternative housing system design. Therefore, the objective of the current study was to evaluate the impact of nutrient and energy intake on production and egg quality parameters from laying hens housed at a commercial facility. Lohmann LSL laying hens were housed in three systems: enriched colony cage, cage-free aviary, and conventional cage at a single commercial facility. Daily production records were collected along with dietary changes during 15 production periods (28-d each). Eggs were analyzed for shell strength, shell thickness, Haugh unit, vitelline membrane properties, and egg solids each period. An analysis of covariance (ANCOVA) coupled with a principal components analysis (PCA) approach was utilized to assess the impact of nutritional changes on production parameters and monitored egg quality factors. The traits of hen-day production and mortality had a response only in the PCA 2 direction. This finds that as house temperature and Met intake increases, there is an inflection point at which hen-day egg production is negatively effected. Dietary changes more directly influenced shell parameters, vitelline membrane parameters, and egg total solids as opposed to laying hen housing system. Therefore, further research needs to be conducted in controlled research settings on laying hen nutrient and energy intake in the alternative housing systems and resulting impact on egg quality measures. PMID:25630672

Impact of commercial housing systems and nutrient and energy intake on laying hen performance and egg quality parameters.

PubMed

Karcher, D M; Jones, D R; Abdo, Z; Zhao, Y; Shepherd, T A; Xin, H

2015-03-01

The US egg industry is exploring alternative housing systems for laying hens. However, limited published research related to cage-free aviary systems and enriched colony cages exists related to production, egg quality, and hen nutrition. The laying hen's nutritional requirements and resulting productivity are well established with the conventional cage system, but diminutive research is available in regards to alternative housing systems. The restrictions exist with limited availability of alternative housing systems in research settings and the considerable expense for increased bird numbers in a replicate due to alternative housing system design. Therefore, the objective of the current study was to evaluate the impact of nutrient and energy intake on production and egg quality parameters from laying hens housed at a commercial facility. Lohmann LSL laying hens were housed in three systems: enriched colony cage, cage-free aviary, and conventional cage at a single commercial facility. Daily production records were collected along with dietary changes during 15 production periods (28-d each). Eggs were analyzed for shell strength, shell thickness, Haugh unit, vitelline membrane properties, and egg solids each period. An analysis of covariance (ANCOVA) coupled with a principal components analysis (PCA) approach was utilized to assess the impact of nutritional changes on production parameters and monitored egg quality factors. The traits of hen-day production and mortality had a response only in the PCA 2 direction. This finds that as house temperature and Met intake increases, there is an inflection point at which hen-day egg production is negatively effected. Dietary changes more directly influenced shell parameters, vitelline membrane parameters, and egg total solids as opposed to laying hen housing system. Therefore, further research needs to be conducted in controlled research settings on laying hen nutrient and energy intake in the alternative housing systems and resulting impact on egg quality measures. © The Author 2015. Published by Oxford University Press on behalf of Poultry Science Association.

Evaluation of the effects of a 4.7-mg deslorelin acetate implant on egg laying in cockatiels (Nymphicus hollandicus).

PubMed

Summa, Noémie M; Guzman, David Sanchez-Migallon; Wils-Plotz, Emma L; Riedl, Nerisa E; Kass, Philip H; Hawkins, Michelle G

2017-06-01

OBJECTIVE To evaluate effects of administration of a 4.7-mg deslorelin acetate implant on egg laying in healthy cockatiels (Nymphicus hollandicus). ANIMALS 52 cockatiels. PROCEDURES 26 breeding pairs (a female and its respective male in each pair) were selected on the basis of their history of egg laying. Female birds were sedated and received a 4.7-mg deslorelin acetate implant (n = 13) or placebo implant (13) in the subcutaneous tissues between the scapulae. Male and female birds of each breeding pair were placed in separate but adjacent cages. Birds were exposed to 16 hours of light and 8 hours of darkness. A nest box was placed in cages of female birds to stimulate reproductive activity. Egg production and quality were monitored daily for 365 days. RESULTS Deslorelin acetate implants significantly suppressed egg laying in cockatiels, compared with effects for the placebo implants. Eleven of 13 placeboimplanted birds laid eggs between 12 and 42 days after implantation. None of the deslorelin-implanted birds laid eggs within 180 days after implantation, and only 5 of 13 deslorelin-implanted birds laid an egg during the study period (first egg laid between 192 and 230 days after implantation). No differences in egg quality or number of eggs per clutch were observed between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Insertion of a 4.7-mg deslorelin acetate implant suppressed egg laying in healthy cockatiels for at least 180 days. Studies are necessary to evaluate effects of a deslorelin acetate implant in other avian species or in association with reproductive disorders.

Identification and characterization of a sex peptide receptor-like transcript from the western tarnished plant bug, Lygus hesperus

USDA-ARS?s Scientific Manuscript database

Lygus hesperus females exhibit a post-mating behavioral switch that triggers increased egg laying and decreased sexual interest. In Drosophila melanogaster, post-mating changes in behavior are controlled by sex peptide (SP) and the sex peptide receptor (DmSPR). SPR is present in most insect genome...

Comparison of the effects of dietary supplementation of flavonoids on laying hen performance, egg quality and egg nutrient profile.

PubMed

Iskender, H; Yenice, G; Dokumacioglu, E; Kaynar, O; Hayirli, A; Kaya, A

2017-10-01

1. The aim of this experiment was to compare the effects of dietary supplementation of hesperidin, naringin and quercetin on laying hen performance, egg quality and egg yolk lipid and protein profiles. 2. A total of 96 Lohmann White laying hens weighing an average of 1500 g at 28 weeks of age were randomly assigned to a basal diet and the basal diet supplemented (0.5 g/kg) with either hesperidin, naringin or quercetin. Each treatment was replicated in 6 cages in an 8-week experimental period. Data were analysed using one-way analysis of variance. 3. None of the dietary flavonoids affected laying performance and eggshell quality. Hesperidin and quercetin supplementations decreased albumen and yolk indexes. 4. As compared to the control group, egg yolk cholesterol content decreased and egg yolk protein content increased in response to dietary hesperidin and quercetin supplementation. The mean egg yolk cholesterol (mg/g) and protein (g/100 g) contents were 10.08/14.28, 16.12/14.08, 14.75/15.04 and 15.15/14.85 for the control group and groups supplemented with naringin, hesperidin and quercetin, respectively. 5. Egg yolk lipid and protein profiles were variable. 6. In conclusion, dietary supplementation of hesperidin or quercetin could be used in the diets during the early laying period to reduce egg yolk cholesterol and increase egg yolk protein, which may be attractive to consumers.

Effects of Bacteriophage Supplementation on Egg Performance, Egg Quality, Excreta Microflora, and Moisture Content in Laying Hens

PubMed Central

Zhao, P. Y.; Baek, H. Y.; Kim, I. H.

2012-01-01

An experiment was conducted to evaluate the effects of bacteriophage supplementation on egg performance, egg quality, excreta microflora, and moisture content in laying hens. A total of 288 Hy-line brown commercial laying hens (36-wk-old) were randomly allotted to 4 treatments in this 6-wk trial and dietary treatments included: i) CON, basal diet; ii) T1, CON+0.020% bacteriophage; iii) T2, CON+0.035% bacteriophage; iv) T3, CON+0.050% bacteriophage. There were 6 replicates for each treatment with 6 adjacent cages (2 hens/cage). Laying hens in T2 and T3 treatments had higher (p<0.05) egg production than those in CON and T1 treatments during wk 0 to 3. In addition, egg production in T1, T2, and T3 treatments was increased (p<0.05) compared with that in CON treatment during wk 4 to 6. At wk 4 and 5, birds in T2 group had higher (p<0.05) HU than those in CON. In addition, at wk 5 and 6, HU in birds fed T1 and T3 diets was greater (p<0.05) than those fed CON diet. E. coli and Salmonella spp. concentrations in excreta were decreased (p<0.05) by T1, T2, and T3 treatments. However, egg weight, egg shell color, yolk height, yolk color unit, egg shell strength, egg shell thickness, egg gravity, and excreta moisture content were not influenced by dietary treatments during the entire experimental period. In conclusion, bacteriophage supplementation has beneficial effects on egg production, egg albumen, and excreta microflora concentration in laying hens. PMID:25049658

Pheromonal Cues Deposited by Mated Females Convey Social Information about Egg-Laying Sites in Drosophila Melanogaster.

PubMed

Duménil, Claire; Woud, David; Pinto, Francesco; Alkema, Jeroen T; Jansen, Ilse; Van Der Geest, Anne M; Roessingh, Sanne; Billeter, Jean-Christophe

2016-03-01

Individuals can make choices based on information learned from others, a phenomenon called social learning. How observers differentiate between which individual they should or should not learn from is, however, poorly understood. Here, we showed that Drosophila melanogaster females can influence the choice of egg-laying site of other females through pheromonal marking. Mated females mark territories of high quality food by ejecting surplus male sperm containing the aggregation pheromone cis-11-vaccenyl acetate (cVA) and, in addition, deposit several sex- and species-specific cuticular hydrocarbon (CHC) pheromones. These pheromonal cues affect the choices of other females, which respond by preferentially laying eggs on the marked food. This system benefits both senders and responders, as communal egg laying increases offspring survival. Virgin females, however, do not elicit a change in the egg-laying decision of mated females, even when food has been supplemented with ejected sperm from mated females, thus indicating the necessity for additional cues. Genetic ablation of either a female's CHC pheromones or those of their mate results in loss of ability of mated females to attract other females. We conclude that mated females use a pheromonal marking system, comprising cVA acquired from male ejaculate with sex- and species-specific CHCs produced by both mates, to indicate egg-laying sites. This system ensures information reliability because mated, but not virgin, females have both the ability to generate the pheromone blend that attracts other flies to those sites and a direct interest in egg-laying site quality.

Comparison of protoporphyrin IX content and related gene expression in the tissues of chickens laying brown-shelled eggs.

PubMed

Li, Guangqi; Chen, Sirui; Duan, Zhongyi; Qu, Lujiang; Xu, Guiyun; Yang, Ning

2013-12-01

Protoporphyrin IX (PpIX), an immediate precursor of heme, is the main pigment resulting in the brown coloration of eggshell. The brownness and uniformity of the eggshell are important marketing considerations. In this study, 9 chickens laying darker brown shelled eggs and 9 chickens laying lighter brown shelled eggs were selected from 464 individually caged layers in a Rhode Island Red pureline. The PpIX contents were measured with a Microplate Reader at the wavelength of 412 nm and were compared in different tissues of the 2 groups. Although no significant difference in serum, bile, and excreta was found between the 2 groups, PpIX content in the shell gland and eggshell of the darker group was higher than in those of the lighter group, suggesting that PpIX was synthesized in the shell gland. We further determined the expression levels of 8 genes encoding enzymes involved in the heme synthesis and transport in the liver and shell gland at 6 h postoviposition by quantitative PCR. The results showed that expression of aminolevulinic acid synthase-1 (ALAS1) was higher in the liver of hens laying darker brown shelled eggs, whereas in the shell gland the expression levels of ALAS1, coproporphyrinogen oxidase (CPOX), ATP-binding cassette family members ABCB7 and ABCG2, and receptor for feline leukemia virus, subgroup C (FLVCR) were significantly higher in the hens laying darker brown shelled eggs. Our results demonstrated that hens laying darker brown shelled eggs could deposit more PpIX onto the eggshell and the brownness of the eggshell was dependent on the total quantity of PpIX in the eggshell. More heme was synthesized in the liver and shell gland of hens laying darker brown shelled eggs than those of hens laying lighter brown shelled eggs. High expression level of ABCG2 might facilitate the accumulation of PpIX in the shell gland.

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.

Hen Welfare in Different Housing Systems

USDA-ARS?s Scientific Manuscript database

Egg production systems have become subject to heightened levels of scrutiny due to animal welfare concerns. Multiple factors such as disease, skeletal and foot health, pest and parasite load, behavior, stress, affective states, nutrition, and genetics influence the level of welfare laying hens exper...

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.

Metabolite exchange between microbiome members produces compounds that influence Drosophila behavior

PubMed Central

Fischer, Caleb N; Trautman, Eric P; Crawford, Jason M; Stabb, Eric V; Handelsman, Jo; Broderick, Nichole A

2017-01-01

Animals host multi-species microbial communities (microbiomes) whose properties may result from inter-species interactions; however, current understanding of host-microbiome interactions derives mostly from studies in which elucidation of microbe-microbe interactions is difficult. In exploring how Drosophila melanogaster acquires its microbiome, we found that a microbial community influences Drosophila olfactory and egg-laying behaviors differently than individual members. Drosophila prefers a Saccharomyces-Acetobacter co-culture to the same microorganisms grown individually and then mixed, a response mainly due to the conserved olfactory receptor, Or42b. Acetobacter metabolism of Saccharomyces-derived ethanol was necessary, and acetate and its metabolic derivatives were sufficient, for co-culture preference. Preference correlated with three emergent co-culture properties: ethanol catabolism, a distinct volatile profile, and yeast population decline. Egg-laying preference provided a context-dependent fitness benefit to larvae. We describe a molecular mechanism by which a microbial community affects animal behavior. Our results support a model whereby emergent metabolites signal a beneficial multispecies microbiome. DOI: http://dx.doi.org/10.7554/eLife.18855.001 PMID:28068220

Rare earth element-enriched yeast improved egg production and egg quality in laying hens in the late period of peak egg production.

PubMed

Cai, L; Nyachoti, C M; Hancock, J D; Lee, J Y; Kim, Y H; Lee, D H; Kim, I H

2016-06-01

The objective of this study was to determine the effects of rare earth element-enriched yeast (RY) on egg production, coefficient of total tract apparent digestibility (CTTAD), egg quality, excreta gas emission and excreta microbiota of laying hens. A total of 216 ISA brown laying hens of 52 weeks of age were used in a 5-week feeding trial and data were collected every week. Birds were randomly allotted to three dietary treatments each with six replicates and 12 hens per replicate. Each cage (38 cm width × 50 cm length × 40 cm height) contained one hen. Treatments consisted of corn-soya bean meal-based diet supplemented with 0, 500 or 1000 mg/kg of RY. From weeks 55 to 56, inclusion of RY linearly increased (p < 0.05) egg production. The CTTAD of nitrogen was increased (linear, p < 0.05) with increasing dietary level of RY. In week 55, yolk height and Haugh units were increased linearly (p < 0.05) with increasing dietary RY content. However, no significant effects were observed in terms of excreta emissions and excreta microbiota in laying hens. In conclusion, dietary supplementation with RY improved egg production and CTTAD of nitrogen and slightly improved egg quality in laying hens of the late period of peak egg production. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Aroclor 1242 and reproductive success of adult mallards (Anas platyrhynchos)

USGS Publications Warehouse

Haseltine, S.D.; Prouty, R.M.

1980-01-01

Twenty-four pairs of adult mallards were fed a diet containing 0 or 150 ppm of the PCB Aroclor 1242 for 12 weeks during which egg laying was induced. Laying started in both groups an average of 33 days after PCB treatment began. All hens were allowed to lay a 20-egg clutch; 15 eggs from each clutch were artificially incubated. Eleven hens from each group completed the clutch. There was no difference between the two groups in the time taken to lay the clutch, nor was there a difference in fertility, embryo mortality, or hatching success. Eggshell thickness decreased 8.9% with PCB ingestion; eggs from hens fed PCB contained an average of 105 ppm PCB wet wt. No difference in survival or weight gain to 3 weeks of age was observed between young mallards from eggs laid by PCB-treated hens and control hens.

Do necrophagous blowflies (Diptera: Calliphoridae) lay their eggs in wounds?: Experimental data and implications for forensic entomology.

PubMed

Charabidze, Damien; Depeme, Aurore; Devigne, Cedric; Hedouin, Valery

2015-08-01

This study was designed to examine the common belief that necrophagous blowflies lay their eggs in wounds. The egg-laying behaviour of Lucilia sericata was observed under controlled conditions on wet, artificially wounded or short-haired areas of rat cadavers. Flies laid significantly more eggs on the wet area and the area with short hair than on the dry area or area with long hair. No eggs were observed inside the wounds in any of the replicates. The effect of egg immersion (body fluids often exudes in wounds) on the survival rate of larvae was also investigated. In low water condition, an average of 72.7±7.9% of the larvae survived and they reached a mean length of 7.5±0.6mm. In contrast, submerging eggs under a high volume of water strongly affected their survival rate (25±3.7%) and development. Similar results were observed using unfrozen pig blood instead of water. These data question the information found in the literature regarding the preferential egg-laying behaviour of Calliphorids flies in wounds. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Differential circular RNAs expression in ovary during oviposition in honey bees.

PubMed

Chen, Xiao; Shi, Wei; Chen, Chao

2018-04-27

Circular RNAs (circRNAs) are non-coding RNAs newly identified and play important roles in RNA regulation. The mechanism and function of circRNAs have been reported in some species. However, little is known regarding circRNAs in honey bees. In this study, we analyzed circRNAs through bioinformatics, and predicted 12,211 circRNAs in the ovary of honey bee queens. 1340, 175 and 100 circRNAs were differentially expressed in comparisons of egg-laying queens vs virgin queens, egg-laying inhibited queens vs egg-laying queens and egg-laying recovery queens vs egg-laying inhibited queens. Further, functional annotation of differentially expressed circRNAs revealed several pathways that are closely related to ovary activation and oviposition, including insulin secretion and calcium signaling pathways. Moreover, the potential interactions among circRNAs, miRNAs, lncRNAs and mRNAs were investigated. Ame_circ_0005197 and ame_circ_0016640 were observed to sponge several reproductive related miRNAs. These findings demonstrate that circRNAs have potential effects in ovary activation and oviposition of honey bees. Copyright © 2018. Published by Elsevier Inc.

The metabolite products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed 15N-CCC containing diets.

PubMed

Chakeredza, S; Edrada, R A; Ebel, R; ter Meulen, U

2006-04-01

An experiment was conducted to evaluate the metabolic products of chlorocholine chloride (CCC) in eggs and meat of laying hens fed a diet containing (15)N-CCC. Ten brown laying hens were randomly divided into two groups of five each. One group was offered (15)N-CCC free diet while the other group received a diet with 100 ppm (15)N-CCC for 11 days. Samples of eggs and meat from the laying hens were collected. Egg yolks and albumen were separated. Meat was collected from the breast and femur. The metabolic products of CCC were measured using ion trap electrospray ionisation mass spectrometry (ion trap-ESI-MS/MS). Determination of CCC or its metabolites in eggs and meat showed that CCC was metabolised to choline. Corresponding MS/MS spectra were obtained for m/z 104 (choline) or 105 ((15)N-choline), whereas nothing was detected at m/z 122 (CCC) or 123 ((15)N-CCC). The results from this study indicate that CCC will be metabolised in tissues of laying hens.

Experimentally reduced corticosterone release promotes early breeding in black-legged kittiwakes.

PubMed

Goutte, Aurélie; Clément-Chastel, Céline; Moe, Børge; Bech, Claus; Gabrielsen, Geir Wing; Chastel, Olivier

2011-06-15

Breeding at the right time is important for successful reproduction. In birds, stressful environmental conditions are known to delay the timing of breeding but the underlying mechanisms are poorly understood. The stress hormone corticosterone appears to be a good candidate for mediating egg-laying date according to early environmental conditions and physiological state. By experimentally reducing the release of corticosterone in black-legged kittiwakes during the pre-laying period, we tested whether egg-laying date was mechanistically linked to corticosterone levels. Male and female kittiwakes were implanted with a low dose of exogenous corticosterone to inhibit endogenous corticosterone production. According to our predictions, the experimental reduction of corticosterone release was paralleled by a significant advancement of egg laying in females (around 4 days earlier). In addition, females with experimentally reduced corticosterone release gained mass during the pre-laying period compared with controls. Ultimately, the advancement of egg laying in females with experimentally reduced corticosterone levels was associated with an enhanced breeding success. This effect was strongly sex specific. In corticosterone-treated male kittiwakes, egg-laying date and reproductive success were not affected, but breeding probability was lower than in controls. This corticosterone treatment did not influence immediate clutch size, or return rate and breeding decision the following year. Our results support the hypothesis that corticosterone secretion during the pre-laying period mediates the timing of breeding in this long-lived seabird, possibly through the dynamics of energy reserves.

Detecting Salmonella Enteritidis in Laying Hens and Eggs after Experimental Infection at Different Oral Dose Levels

USDA-ARS?s Scientific Manuscript database

The attribution of human illness to eggs contaminated with Salmonella Enteritidis has led to substantial commitments of resources (by both government and industry) to risk reduction and testing programs in egg-laying flocks. Cost-effective application of testing requires a thorough understanding of ...

Bone sialoprotein keratan sulfate proteoglycan (BSP-KSPG) and FGF-23 are important physiological components of medullary bone.

PubMed

Hadley, Jill A; Horvat-Gordon, Maria; Kim, Woo-Kyun; Praul, Craig A; Burns, Dennis; Leach, Roland M

2016-04-01

Medullary bone is a specialized bone found in the marrow cavity of laying birds. It provides a significant contribution to the calcium supply for egg shell formation. Medullary bone is distinguished from cortical bone by the presence of large amounts of a keratan sulfate proteoglycan (KSPG). The aims of the present experiment are to confirm the identity of the core protein of KSPG, identify a marker of medullary bone metabolism, and determine whether changes in keratan sulfate (KS) concentration in blood are associated with the egg-laying cycle. Using two different isolation techniques- one specific for bone and another for blood- we have identified bone sialoprotein (BSP) to be the core protein of this KSPG. We also determined that the amount of keratan sulfate (KS) in laying hen blood fluctuates in synchrony with the egg-laying cycle, and thus can serve as a specific marker for medullary bone metabolism. During the course of this investigation, we also found FGF-23 (phosphatonin) to be expressed in medullary bone, in synchrony with the egg-laying cycle. Western blotting was used to demonstrate the presence of this peptide in both laying hen blood and medullary bone extracts. The importance of FGF-23 (phosphatonin) and parathyroid hormone in normalizing the dramatic changes in plasma calcium and phosphorus during the 24h egg-laying cycle is discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Pinworm (for Parents)

MedlinePlus

... the area around the rectum. There, they will lay new pinworm eggs, which trigger itching around the ... move to the area around the rectum to lay their eggs. In girls, pinworm infection can spread ...

Hourly laying patterns of the Pearly-eyed Thrasher (Margarops fuscatus) in Puerto Rico

Treesearch

Wayne Arendt

2011-01-01

Temporal aspects of egg deposition are important factors governing avian reproductive success. I report hourly egg-laying patterns of the Pearly-eyed Thrasher (Margarops fuscatus) in the Luquillo Experimental Forest in northeastern Puerto Rico during 1979–2000. Initiatory eggs were laid by early morning (median 5 0642 hrs, AST) and almost half of the eggs were laid by...

Effect of superdosing phytase on productive performance and egg quality in laying hens.

PubMed

Kim, Jong Hyuk; Pitargue, Franco Martinez; Jung, Hyunjung; Han, Gi Ppeum; Choi, Hyeon Seok; Kil, Dong Yong

2017-07-01

An experiment was conducted to determine the effect of superdosing phytase on productive performance and egg quality in laying hens. A total of 200 42-wk-old Hy-Line Brown laying hens were allotted into 1 of 5 dietary treatments with 5 replicates consisting of 8 hens per replicate. The positive control (PC) and negative control diets (NC) were prepared based on the recommended P levels in layer diets. Supplemental phytase was added to the negative control diet at 10,000 (SD10), 20,000 (SD20), or 30,000 (SD30) fytase units (FTU)/kg. Productive performance was summarized for 6 weeks from 42 weeks to 47 weeks of age. Egg quality was assessed from 4 eggs per replicate randomly collected at the conclusion of the experiment. The SD20 treatment had greater (p<0.05) hen-day egg production than PC, NC, and SD10 treatment groups. There was no difference in hen-day egg production between SD20 and SD30 treatment groups. However, SD30 treatment had greater (p<0.05) hen-day egg production than PC treatment, but showed no difference in hen-day egg production as compared to NC and SD10 treatment groups. However, egg weight, egg mass, feed intake, and feed conversion ratio were not affected by dietary treatments. Egg quality including eggshell strength, eggshell color, egg yolk color, and haugh unit was not influenced by dietary treatments. Superdosing level of 20,000 FTU/kg phytase in diets has a positive effect on egg production rate, but no beneficial effect on egg quality in laying hens.

Egg-laying sequence influences egg mercury concentrations and egg size in three bird species: Implications for contaminant monitoring programs.

PubMed

Ackerman, Joshua T; Eagles-Smith, Collin A; Herzog, Mark P; Yee, Julie L; Hartman, C Alex

2016-06-01

Bird eggs are commonly used in contaminant monitoring programs and toxicological risk assessments, but intraclutch variation and sampling methodology could influence interpretability. The authors examined the influence of egg-laying sequence on egg mercury concentrations and burdens in American avocets, black-necked stilts, and Forster's terns. The average decline in mercury concentrations between the first and last eggs laid was 33% for stilts, 22% for terns, and 11% for avocets, and most of this decline occurred between the first and second eggs laid (24% for stilts, 18% for terns, and 9% for avocets). Trends in egg size with egg-laying order were inconsistent among species, and overall differences in egg volume, mass, length, and width were <3%. The authors summarized the literature, and among 17 species studied, mercury concentrations generally declined by 16% between the first and second eggs laid. Despite the strong effect of egg-laying sequence, most of the variance in egg mercury concentrations still occurred among clutches (75-91%) rather than within clutches (9%-25%). Using simulations, the authors determined that accurate estimation of a population's mean egg mercury concentration using only a single random egg from a subset of nests would require sampling >60 nests to represent a large population (10% accuracy) or ≥14 nests to represent a small colony that contained <100 nests (20% accuracy). Environ Toxicol Chem 2016;35:1458-1469. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America. Published 2015 Wiley Periodicals Inc. on behalf of SETAC. This article is a US Government work and, as such, is in the public domain in the United States of America.

Individual variation in prelaying behaviour and the incidence of floor eggs.

PubMed

Cooper, J J; Appleby, M C

1996-05-01

1. Floor eggs are a problem in non-cage systems for laying hens, as they require secondary egg collecting. Failure to lay in a well-defined nest site may also be a welfare problem for the hens, but only if their nesting motivation has been thwarted. We investigated the relationships between a hen's prelaying behaviour and its tendency to lay on the floor by recording the behaviour of 20 hens housed individually in wire cages with single littered nest boxes. 3. Most floor eggs (80%) were laid by the same 6 hens. These 6 "floor-layers" performed more nest seeking behaviour, less nest-building behaviour and less sitting prior to oviposition than the 14 hens that consistently laid in nest boxes. 4. The incidence of floor eggs declined with age. Both nest and floor laying hens performed less nest seeking behaviour with age. Floor layers, however, increased their performance of nesting behaviour, whilst nest layers performed less nesting behaviour with age. 5. Floor laying hens behaved as if they found the nest box less attractive than nest-laying hens; perhaps because they had lower nesting motivation, or perhaps because their nesting motivation was as high, but they less readily perceived the nest box as an appropriate nest site.

Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis.

PubMed

Gantois, Inne; Ducatelle, Richard; Timbermont, Leen; Boyen, Filip; Bohez, Lotte; Haesebrouck, Freddy; Pasmans, Frank; van Immerseel, Filip

2006-09-11

Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.

Preliminary evaluation of a nest usage sensor to detect double nest occupations of laying hens.

PubMed

Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

2015-01-26

Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage "sensor", based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

Preliminary Evaluation of a Nest Usage Sensor to Detect Double Nest Occupations of Laying Hens

PubMed Central

Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

2015-01-01

Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage “sensor”, based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices. PMID:25629704

Betaine does not improve performance of laying hens when the diet contains adequate choline.

PubMed

Harms, R H; Russell, G B

2002-01-01

An experiment was conducted with Hy-Line W36 hens to determine possible benefits from adding betaine to the diet of commercial laying hens. There was no benefit from the substitution of betaine for choline as measured by egg production, egg weight, egg content, or weight gain.

Effects of nitrogen on egg-laying inhibition and ovicidal response in planthopper-resistant rice varieties.

PubMed

Horgan, Finbarr G; Srinivasan, Thanga Suja; Naik, Bhaskar S; Ramal, Angelee Fame; Bernal, Carmencita C; Almazan, Maria Liberty P

2016-11-01

A series of experiments was set up to examine the effects of nitrogen on rice ( Oryza sativa L.) resistance against Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth). Egg laying by N. lugens was reduced on the indica variety IR60. Nymph biomass ( N. lugens and S. furcifera ) was also lower on IR60: this was associated with low honeydew production and a high proportion of xylem-derived honeydew in N. lugens but not in S. furcifera . Nitrogen increased egg-laying by S. furcifera and increased N. lugens nymph biomass on all varieties tested. Oviposition and egg mortality in both planthopper species were examined on plants at 15, 30 and 45 days after sowing (DAS). Sogatella furcifera laid more eggs on plants at 15 DAS, but laid few eggs during darkness; N. lugens continued to lay eggs on older rice plants (30 DAS) and during darkness. Egg mortality was high on cv. Asiminori, highest at 45 DAS, and higher for S. furcifera than for N. lugens . Mortality of S. furcifera eggs was associated with lesions around the egg clusters. These were more common around clusters laid during the day and suggested induction by Asiminori of an ovicidal response. Egg mortality declined under higher soil nitrogen levels. Results are discussed in the light of improving rice resistance against planthoppers and reducing rates of planthopper adaptation to resistance genes.

Parasitic egg rejection decisions of chalk-browed mockingbirds Mimus saturninus are independent of clutch composition.

PubMed

de la Colina, M A; Pompilio, L; Hauber, M E; Reboreda, J C; Mahler, B

2018-03-01

Obligate avian brood parasites lay their eggs in nests of other host species, which assume all the costs of parental care for the foreign eggs and chicks. The most common defensive response to parasitism is the rejection of foreign eggs by hosts. Different cognitive mechanisms and decision-making rules may guide both egg recognition and rejection behaviors. Classical optimization models generally assume that decisions are based on the absolute properties of the options (i.e., absolute valuation). Increasing evidence shows instead that hosts' rejection decisions also depend on the context in which options are presented (i.e., context-dependent valuation). Here we study whether the chalk-browed mockingbird's (Mimus saturninus) rejection of parasitic shiny cowbird (Molothrus bonariensis) eggs is a fixed behavior or varies with the context of the clutch. We tested three possible context-dependent mechanisms: (1) range effect, (2) habituation to variation, and (3) sensitization to variation. We found that mockingbird rejection of parasitic eggs does not change according to the characteristics of the other eggs in the nest. Thus, rejection decisions may exclusively depend on the objective characteristics of the eggs, meaning that the threshold of acceptance or rejection of a foreign egg is context-independent in this system.

Mechanism and ecological significance of sperm storage in the Northern Fulmar with reference to its occurrence in other birds

USGS Publications Warehouse

Hatch, Scott A.

1983-01-01

Sperm-storage glands were found in the uterovaginal (UV) region of the oviduct in Northern Fulmars (Fulmarus glacialis), Horned Puffins (Fratercula corniculata), and Leach's Storm-Petrels (Oceanodroma leucorhoa) collected before or shortly after egg laying. Previously described only in domestic Galliformes, UV sperm-storage glands may prove to be a common feature of the avian reproductive system. There is as yet no compelling explanation of their function in the Horned Puffin. In the Northern Fulmar, and probably in other petrels, however, sperm-storage glands allow the separation of the male and female over pelagic waters for several weeks immediately before egg laying. The likelihood of prolonged viability of sperm in the female reproductive tract should be considered in interpreting the sexual behavior of other wild birds.

Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens of four commercial genetic lines in conventional cage and enriched colony housing

USDA-ARS?s Scientific Manuscript database

Human infections with Salmonella Enteritidis are often attributed to the consumption of contaminated eggs, so the prevalence of this pathogen in commercial egg-laying flocks is a significant public health concern. Internal contamination of the edible contents of eggs results from bacterial colonizat...

Colonization of internal organs by Salmonella serovars Heidelberg and Typhimurium in experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Contaminated eggs produced by infected commercial laying flocks are often implicated as sources of human infections with Salmonella Enteritidis, but Salmonella serovars Heidelberg and Typhimurium have also been associated with egg-transmitted illness. Contamination of the edible contents of eggs is ...

Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

The frequency of human infections with Salmonella Enteritidis (SE) has been linked to contaminated eggs and thus to SE prevalence in commercial egg-laying flocks. Contamination of the edible contents of eggs is a consequence of SE colonization of reproductive tissues in systemically infected hens. T...

Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Epidemiologic analyses have linked the frequency of human infections with Salmonella enterica subspecies enterica serovar Enteritidis to the consumption of contaminated eggs and thus to the prevalence of this pathogen in commercial egg-laying flocks. Contamination of the edible contents of eggs by S...

Frequency and persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Human Salmonella Enteritidis infections are often linked with consuming contaminated eggs, so the prevalence of this pathogen in egg-laying poultry is an important risk factor for public health. Salmonella persistence and transmission in commercial egg producing flocks are influenced by the complex ...

Keeping eggs warm: thermal and developmental advantages for parasitic cuckoos of laying unusually thick-shelled eggs

NASA Astrophysics Data System (ADS)

Yang, Canchao; Huang, Qiuli; Wang, Longwu; Du, Wei-Guo; Liang, Wei; Møller, Anders Pape

2018-02-01

Obligate brood parasites have evolved unusually thick-shelled eggs, which are hypothesized to possess a variety of functions such as resistance to puncture ejection by their hosts. In this study, we tested the hypothesis that obligate brood parasites lay unusually thick-shelled eggs to retain more heat for the developing embryo and thus contribute to early hatching of parasite eggs. By doing so, we used an infrared thermal imaging system as a non-invasive method to quantify the temperature of eggshells of common cuckoos ( Cuculus canorus) and their Oriental reed warbler ( Acrocephalus orientalis) hosts in an experiment that artificially altered the duration of incubation. Our results showed that cuckoo eggshells had higher temperature than host eggs during incubation, but also less fluctuations in temperature during incubation disturbance. Therefore, there was a thermal and hence a developmental advantage for brood parasitic cuckoos of laying thick-shelled eggs, providing another possible explanation for the unusually thick-shelled eggs of obligate brood parasites and earlier hatching of cuckoo eggs compared to those of the host.

Keeping eggs warm: thermal and developmental advantages for parasitic cuckoos of laying unusually thick-shelled eggs.

PubMed

Yang, Canchao; Huang, Qiuli; Wang, Longwu; Du, Wei-Guo; Liang, Wei; Møller, Anders Pape

2018-01-02

Obligate brood parasites have evolved unusually thick-shelled eggs, which are hypothesized to possess a variety of functions such as resistance to puncture ejection by their hosts. In this study, we tested the hypothesis that obligate brood parasites lay unusually thick-shelled eggs to retain more heat for the developing embryo and thus contribute to early hatching of parasite eggs. By doing so, we used an infrared thermal imaging system as a non-invasive method to quantify the temperature of eggshells of common cuckoos (Cuculus canorus) and their Oriental reed warbler (Acrocephalus orientalis) hosts in an experiment that artificially altered the duration of incubation. Our results showed that cuckoo eggshells had higher temperature than host eggs during incubation, but also less fluctuations in temperature during incubation disturbance. Therefore, there was a thermal and hence a developmental advantage for brood parasitic cuckoos of laying thick-shelled eggs, providing another possible explanation for the unusually thick-shelled eggs of obligate brood parasites and earlier hatching of cuckoo eggs compared to those of the host.

Outer membrane vesicles of Gallibacterium anatis induce protective immunity in egg-laying hens.

PubMed

Pors, Susanne E; Pedersen, Ida J; Skjerning, Ragnhild Bager; Thøfner, Ida C N; Persson, Gry; Bojesen, Anders M

2016-11-15

Gallibacterium anatis causes infections in the reproductive tract of egg-laying hens and induce increased mortality and decreased egg production. New prophylactic measures are needed in order to improve animal welfare and production efficiency. Bacterial outer membrane vesicles (OMVs) have previously shown promising results in protection against infections and we hypothesized that OMVs could serve as an immunogen to protect egg-laying hens against G. anatis. To investigate the immunogenic potential of G. anatis OMVs, two in vivo studies in egg-laying hens were made. The trials assessedthe degree of protection provided by immunization with G. anatis OMV against challenge and the IgY responses in serum after immunization and challenge, respectively. A total of 64 egg-laying hens were included in the trials. OMVs for immunization were produced and purified from a high-producing G. anatis ΔtolR mutant. Challenge was done with G. anatis 12656-12 and evaluated by scoring lesions and bacterial re-isolation rates from peritoneum. Finally, levels of OMV-specific IgY in sera were assayed by ELISA. Immunization with OMVs decreased the lesions scores significantly, while the bacterial re-isolation remained unchanged. Furthermore, a high OMV-specific IgY response was induced by immunization and subsequent challenge of the hens. The results strongly indicate that immunization with G. anatis OMVs provides significant protection against G. anatis challenge and induces specific antibody responses with high titers of OMV-specific IgY in serum. The results therefore show great promise for OMV based vaccines aiming at providing protecting against G. anatis in egg-laying hens. Copyright © 2016 Elsevier B.V. All rights reserved.

Oviposition in Delia platura (Diptera, Anthomyiidae): the role of volatile and contact cues of bean.

PubMed

Gouinguené, Sandrine P; Städler, Erich

2006-07-01

The choice of a suitable oviposition site by female insects is essential for survival of their progeny. Both olfactory and contact cues of the oviposition site may mediate this choice. The polyphagous Delia platura (Diptera: Anthomyiidae), a severe agricultural pest of numerous crops, lays eggs in the soil close to germinating seeds. Maggots feed upon the cotyledons. Only little is known about the cues guiding oviposition behavior. In this study, the effects of both olfactory and contact cues of beans (Phaseolus vulgaris) on oviposition of D. platura females were tested. Egg deposition on germinated beans was preferred to egg deposition on ungerminated beans or on beans in different postgerminating developmental stages. Olfactory cues of germinating beans alone stimulated female flies to lay eggs. Additional contact cues of germinating beans seemed to enhance the response, but the difference was not significant. Surface extracts of germinating beans sprayed on surrogate beans showed that both polar and nonpolar substances stimulated oviposition of D. platura flies. Gas chromatography-electroantennographic detection recordings of head space samples of germinating beans showed positive response of females to different compounds. We conclude that olfaction plays a major role when D. platura females are searching for oviposition sites. Volatile compounds released from germinating beans such as 4-hydroxy-4-methyl-2-pentanone, 1-hepten-3-one, 1-octen-3-ol, and 3-octanone should be considered as key compounds that mediate oviposition behavior. The use of different sensory modalities by closely related species of Delia is discussed.

A model approach to project the start of egg laying of Great Tit (Parus major L.) in response to climate change.

PubMed

Chmielewski, Frank-M; Blümel, Klaus; Scherbaum-Heberer, Carina; Koppmann-Rumpf, Bettina; Schmidt, Karl-Heinz

2013-03-01

The aim of this study was to select a phenological model that is able to calculate the beginning of egg laying of Great Tit (Parus major) for both current and future climate conditions. Four models (M1-M4) were optimised on long-term phenological observations from the Ecological Research Centre Schlüchtern (Hessen/Germany). Model M1 was a common thermal time model that accumulates growing degree days (GDD) on an optimised starting date t (1). Since egg laying of Great Tit is influenced not only by air temperature but also by photoperiod, model M1 was extended by a daylength term to give M2. The other two models, M3 and M4, correspond to M1 and M2, but t (1) was intentionally set to 1 January, in order to consider already rising temperatures at the beginning of the year. A comparison of the four models led to following results: model M1 had a relatively high root mean square error at verification (RMSE(ver)) of more than 4 days and can be used only to calculate the start of egg laying for current climate conditions because of the relatively late starting date for GDD calculation. The model failed completely if the starting date was set to 1 January (M3). Consideration of a daylength term in models M2 and M4 improved the performance of both models strongly (RMSE(ver) of only 3 days or less), increased the credibility of parameter estimation, and was a precondition to calculate reliable projections in the timing of egg laying in birds for the future. These results confirm that the start of egg laying of Great Tit is influenced not only by air temperature, but also by photoperiod. Although models M2 and M4 both provide comparably good results for current climate conditions, we recommend model M4-with a starting date of temperature accumulation on 1 January-for calculating possible future shifts in the commencement of egg laying. Our regional projections in the start of egg laying, based on five regional climate models (RCMs: REMO-UBA, ECHAM5-CLM, HadCM3-CLM, WETTREG-0, WETTREG-1, GHG emission scenario A1B), indicate that in the near future (2011-2040) no significant change will take place. However, in the mid- (2041-2070) and long-term (2071-2100) range the beginning of egg laying could be advanced significantly by up to 11 days on average of all five RCMs. This result corresponds to the already observed shift in the timing of egg laying by about 1 week, due mainly to an abrupt increase in air temperature at the end of the 1980s by 1.2 K between April and May. The use of five regional climate scenarios additionally allowed to estimate uncertainties among the RCMs.

Optimization of dietary zinc for egg production and antioxidant capacity in Chinese egg-laying ducks fed a diet based on corn-wheat bran and soybean meal.

PubMed

Chen, W; Wang, S; Zhang, H X; Ruan, D; Xia, W G; Cui, Y Y; Zheng, C T; Lin, Y C

2017-07-01

The aim of this study was to evaluate the effect of zinc supplementation on productive performance and antioxidant status in laying ducks. Five-hundred-four laying ducks were divided into 7 treatments, each containing 6 replicates of 12 ducks. The ducks were caged individually and fed a corn-soybean meal and wheat bran basal diet (37 mg Zn/kg) or the basal diet supplemented with 15, 30, 45, 60, 75, or 90 mg Zn/kg (as zinc sulfate). During the early laying period of 10 d (daily egg production <80%), egg production, daily egg mass, and FCR increased quadratically with increasing dietary Zn levels (P < 0.05). The highest egg production and daily egg weight were obtained when 30 or 45 mg Zn/kg diet was supplemented, with lowest FCR. Similarly, the highest egg production and daily egg mass were observed in the group supplemented with 30 or 45 mg Zn/kg during the peak laying period of the subsequent 120 d (daily egg production >80%). Average egg weight and feed intake did not differ among the groups of graded Zn supplementation.The egg quality was not affected by dietary Zn, including the egg shape index, Haugh unit, yolk color score, egg composition, and shell thickness. The activities of plasma activities of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) increased in a quadratic manner (P < 0.001) with increasing supplemental Zn. Plasma concentration of Zn increased quadratically (P < 0.05) as dietary Zn increased. The hepatic activity of Cu/Zn-SOD and GSH-PX increased quadratically (P < 0.05) with increasing dietary Zn. Plasma Zn concentrations were positively correlated with activities of T-SOD (P < 0.05), and positively with plasma Cu. Plasma concentration of reduced glutathione was correlated with plasma Cu. In conclusion, supplementation of Zn at 30 or 45 mg/kg to a corn-wheat bran and soybean basal diet may improve the productive performance and enhance the antioxidant capacity. © 2017 Poultry Science Association Inc.

Laying performance and egg quality of blue-shelled layers as affected by different housing systems.

PubMed

Wang, X L; Zheng, J X; Ning, Z H; Qu, L J; Xu, G Y; Yang, N

2009-07-01

Blue-shelled eggs are gaining popularity as the consumption demand diversifies in some countries. This study was carried out to investigate the laying performance and egg quality of the blue-shelled egg layers as well as the effects of different housing systems on egg production and quality traits. One thousand pullets from Dongxiang blue-shelled layers were divided into 2 even groups and kept in different housing systems (outdoor vs. cage). Daily laying performance was recorded from 20 to 60 wk of age. External and internal egg quality traits were examined at 26, 34, 42, and 50 wk. Yolk cholesterol concentration and whole egg cholesterol content were measured at 40 wk of age. Average laying rate from 20 to 60 wk for the cage (54.7%) was significantly higher than that of outdoor layers (39.3%). Among all of the egg quality traits, only eggshell color was affected by housing system. Interaction between housing system and layer age was found in egg weight, eggshell color, eggshell ratio, yolk color, and yolk weight. Meanwhile, cholesterol concentration in yolk was 8.64 +/- 0.40 mg/g in the outdoor eggs, which was significantly lower than that of eggs from the cage birds (10.32 +/- 0.48 mg/g; P < 0.05). Whole egg cholesterol content in the outdoor eggs (125.23 +/- 6.32 mg/egg) was also significantly lower than that of eggs from the caged layers (158.01 +/- 8.62 mg/egg). The results demonstrated that blue-shelled layers have lower productivity in the outdoor system than in the cage system. Blue-shelled layers have lower egg weight, larger yolk proportion, and lower cholesterol content compared with commercial layers. In a proper marketing system, lower productivity could be balanced by a higher price for the better quality of blue-shelled eggs.

Effects of different vaccine combinations against Mycoplasma gallisepticum on the digestive and reproductive organ characteristics of commercial egg-laying hens

USDA-ARS?s Scientific Manuscript database

Mycoplasma gallisepticum (MG) is a major and economically significant pathogen of avian species. When administered before lay, F-strain MG (FMG) can reduce egg production during lay, but the ts-11 strain of MG (ts11MG) does not exert this effect. Two trials were conducted to determine the effects ...

Infection of the reproductive tract and eggs with Salmonella enterica serovar pullorum in the chicken is associated with suppression of cellular immunity at sexual maturity.

PubMed

Wigley, Paul; Hulme, Scott D; Powers, Claire; Beal, Richard K; Berchieri, Angelo; Smith, Adrian; Barrow, Paul

2005-05-01

Salmonella enterica serovar Pullorum causes persistent infections in laying hens. Splenic macrophages are the main site of persistence. At sexual maturity, numbers of bacteria increase and spread to the reproductive tract, which may result in vertical transmission to eggs or chicks. In this study we demonstrate that both male and female chickens may develop a carrier state following infection but that the increases in bacterial numbers and spread to the reproductive tract are phenomena restricted to hens, indicating that such changes are likely to be related to the onset of egg laying. The immunological responses during the carrier state and through the onset of laying in hens were determined. These indicate that chickens produce both humoral and T-cell responses to infection, but at the onset of laying both the T-cell response to Salmonella and nonspecific responses to mitogenic stimulation fall sharply in both infected and noninfected birds. The fall in T-cell responsiveness coincided with the increase in numbers of Salmonella serovar Pullorum and its spread to the reproductive tract. Three weeks after the onset of egg laying, T-cell responsiveness began to increase and bacterial numbers declined. Specific antibody levels changed little at the onset of laying but increased following the rise in bacterial numbers in a manner reminiscent of a secondary antibody response to rechallenge. These findings indicate that a nonspecific suppression of cellular responses occurs at the onset of laying and plays a major role the ability of Salmonella serovar Pullorum to infect the reproductive tract, leading to transmission to eggs. The loss of T-cell activity at the point of laying also has implications for Salmonella enterica serovar Enteritidis infection and transmission to eggs, along with its control by vaccination offering a "window of opportunity" in which infection may occur.

Effect of dietary γ-aminobutyric acid on laying performance, egg quality, immune activity and endocrine hormone in heat-stressed Roman hens.

PubMed

Zhang, Min; Zou, Xiao-Ting; Li, Hui; Dong, Xin-Yang; Zhao, Wenjing

2012-02-01

This study was conducted to evaluate the effect of γ-aminobutyric acid (GABA) on laying performance, egg quality, digestive enzyme activity, hormone level and immune activities in Roman hens under heat stress. Roman hens (320 days old) were fed with 0, 25, 50, 75 and 100 mg/kg GABA, respectively during a 60-day experiment. Compared with control, supplementation of 50 mg/kg GABA improved the laying performance and egg quality by significantly increasing egg production, average egg weight and shell strength (P < 0.05), while decreasing the feed-egg ratio and cholesterol level. Anti-oxidation activity was improved by significantly increasing the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), but decreasing malondialdehyde level in serum (P < 0.05), while significantly increasing the glucose and total protein (TP) level, follicle stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E(2) ), insulin, triiodothyronine (T(3) ) and free triiodothyronine (FT(3) ) levels, and IgG, IgA and complement (C3)activity in serum (P < 0.05). The results indicated that oral GABA improved laying performance and physical condition mainly by modulating hormone secretion, enhancing anti-oxidation and immune activity, and maintaining electrolyte balance. Fifty mg/kg was the optimum level for laying hens under heat stress in the present study. © 2011 The Authors. Animal Science Journal © 2011 Japanese Society of Animal Science.

Introduction--the Socially Sustainable Egg Production project.

PubMed

Swanson, J C; Mench, J A; Thompson, P B

2011-01-01

The social and political pressure to change egg production from conventional cage systems to alternative systems has been largely driven by the desire to provide more behavioral freedom for egg-laying hens. However, a change of this magnitude can affect other components of the production system and may result in unintended outcomes. To understand this issue, a Socially Sustainable Egg Production project was formed to 1) conduct a holistic and integrated systematic review of the current state of knowledge about various aspects of sustainable egg production, and 2) develop a coordinated grant proposal for future extramural funding based on the research priorities identified from the review. Expert study groups were formed to write evidence-based papers in 5 critical sustainability areas: hen health and welfare, economics, food safety and quality, public attitudes, and environmental impacts. These papers were presented as the PSA Emerging Issues Symposium on Social Sustainability of Egg Production at the 2010 Poultry Science Association meeting.

Effect of feeding duration of diets containing corn distillers dried grains with solubles on productive performance, egg quality, and lutein and zeaxanthin concentrations of egg yolk in laying hens.

PubMed

Shin, H S; Kim, J W; Kim, J H; Lee, D G; Lee, S; Kil, D Y

2016-10-01

This experiment was conducted to investigate the effect of feeding duration of diets containing corn distillers dried grains with solubles (DDGS) on productive performance, egg quality, and lutein and zeaxanthin concentrations of egg yolk in laying hens. A total of 300 57-week-old Hy-Line Brown laying hens were randomly assigned to one of 5 treatment groups (feeding duration) with 6 replicates consisting of 5 consecutive cages with 2 hens per cage. Diets were formulated to contain either 0% (the control diet) or 20% DDGS. Experimental diets were fed to hens for 12 wk. The feeding duration of diets containing 20% DDGS was 0, 3, 6, 9, or 12 wk before the conclusion of the experiment. Feeding the diet containing 20% DDGS for 3, 6, or 9 wk followed feeding the control diet for 9, 6, or 3 wk, respectively. The data for productive performance were summarized for 12 wk of the feeding trial. Results indicated that increasing feeding duration of diets containing 20% DDGS had no effects on productive performance of laying hens, but increased egg yolk color (linear, P < 0.01), hunter a* value (linear and quadratic, P < 0.01), and b* values (linear, P < 0.05) with a decrease in hunter L* value (linear and quadratic, P < 0.05). Lutein and zeaxanthin concentrations of egg yolks also were increased (linear, P < 0.01) by increasing the feeding duration of diets containing 20% DDGS. In conclusion, feeding diets containing 20% DDGS to laying hens has no adverse effects on productive performance. Increasing the feeding duration of diets containing 20% DDGS improves egg yolk coloration with a concomitant increase in lutein and zeaxanthin concentrations of egg yolks in laying hens. © 2016 Poultry Science Association Inc.

Exterior and interior physical quality of egg of laying hens fed diets containing different dietary purslane levels

NASA Astrophysics Data System (ADS)

Kartikasari, L. R.; Hertanto, B. S.; Pranoto, D.; Salim, W. N.; Nuhriawangsa, A. M. P.

2017-04-01

Purslane is considered a rich vegetable source of alpha-linolenic acid, beta-carotene and various antioxidants. The objective of the study was to investigate the effect of different dietary levels of purslane meal (Portulaca oleracea) in the diets of laying hens on physical quality of eggs. A total of 125 Hy-Line Brown hens (54 weeks old) were placed at individual cages and assigned to five dietary treatments. The diets were supplemented with 0, 2, 4, 6 and 8% purslane meal. Laying hens were fed for 5 weeks after a typical period of adaptation (7 days). Water and feed were provided ad libitum. A total of 25 egg samples of day 28 and day 35 (n = 5 egg yolks for each treatment) were collected to analyse exterior and interior physical quality of eggs. The data were analysed using ANOVA. Differences between treatment means were further analysed using Duncan’s New Multiple Range Test. Results showed that feeding different purslane meal levels in the diets improved egg weight, yolk weight, albumen weight and yolk colour. The highest intensity of yolk colour was obtained with the diet containing 8% purslane meal. However, dietary treatments did not affect egg index, albumen index, yolk index, shell weight, shell thickness and Haugh Unit. It is concluded that including purslane meal to laying hen diets increases the physical qualities of the eggs.

Influence of Zeolite on fatty acid composition and egg quality in Tunisian Laying Hens

PubMed Central

2012-01-01

Background The health benefits of omega-3 and omega-6 polyunsaturated fatty acids (PUFA) are generally recognized. Unfortunately, in most Mediterranean countries, the recommended daily intake of these compounds is rarely met. Therefore, enrichment of commonly occurring foods can boost intake of these fatty acids. In this regard, eggs are an interesting target, as they form an integral part of the diet. Result Zeolite (Clinoptilolites) was added to Laying Hens feed at concentrations 1% or 2% and was evaluated for its effects on performance of the production and on egg quality. The Laying Hens were given access to 110 g of feed mixtures daily that was either a basal diet or a ‘zeolite diet’ (the basal diet supplemented with clinoptilolite at a level of 1% or 2%). It was found that zeolite treatment had a positive and significatif (p < 0.05) effect on some parameters that were measured like egg height and eggshell strength. While dietary zeolite supplementation tended to/or has no significant effects on total egg, eggshell, yolk and albumen weights. It was found also that zeolite mainly increases level of polyunsaturated fatty acids in egg. Conclusion This study showed the significance of using zeolite, as a feed additive for Laying Hens, as part of a comprehensive program to control egg quality and to increase level of polyunsaturated fatty acids on egg. PMID:22676421

Camelina meal increases egg n-3 fatty acid content without altering egg quality or production in laying hens

USDA-ARS?s Scientific Manuscript database

Camelina sativa is an oilseed plant rich in n-3 and n-6-fatty acids and extruding defatted seed meal results in high protein meal (~40%) containing residual n-3 fatty acids. We examined the effects of feeding extruded defatted camelina seed meal to commercial laying hens on egg production, quality, ...

Nutritional quality of eggs from hens fed distillers dried grains with solubles.

PubMed

Trupia, S; Winkler-Moser, J K; Guney, A C; Beckstead, R; Chen, C-Y O

2016-11-01

A feeding trial was conducted with laying hens where either 10% or 20% regular-fat distiller's dried grains with solubles (R-DDGS) or low-fat DDGS (L-DDGS) were incorporated into the feed. Production parameters and the effect of DDGS on egg nutritional quality, focusing on yolk lipids, were evaluated. Neither R-DDGS nor L-DDGS at up to 20% of laying hen feeds had a statistically significant impact on hen weight gain, egg production, feed intake, feed efficiency, egg mass, or egg weight. Specific gravity was slightly lower for eggs from hens fed 10% R-DDGS or 20% L-DDGS. Eggs from layers fed DDGS had enhanced levels of tocopherols, tocotrienols, and xanthophylls in the yolk, as well as also increased yolk yellow and red color. Eggs from L-DDGS diet had higher tocopherol content, but eggs from R-DDGS diets had higher xanthophylls. Fatty acid composition in eggs was slightly altered by DDGS, but the ratio of saturated to unsaturated fatty acids was very similar. Feeding DDGS to layer hens had no effect on lecithin or cholesterol content of the eggs. Thus, inclusion of DDGS in the diet of laying hens resulted in increases of several beneficial lipophilic nutrients in egg yolks with no apparent detrimental effects. © 2016 Poultry Science Association Inc.

Effect of dietary pomegranate seed oil on laying hen performance and physicochemical properties of eggs.

PubMed

Kostogrys, Renata B; Filipiak-Florkiewicz, Agnieszka; Dereń, Katarzyna; Drahun, Anna; Czyżyńska-Cichoń, Izabela; Cieślik, Ewa; Szymczyk, Beata; Franczyk-Żarów, Magdalena

2017-04-15

The objective of the study was to determine the effects of pomegranate seed oil, used as a source of punicic acid (CLnA) in the diets of laying hens, on the physicochemical properties of eggs. Forty Isa Brown laying hens (26weeks old) were equally subjected to 4 dietary treatments (n=10) and fed a commercial layer diet supplying 2.5% sunflower oil (control) or three levels (0.5, 1.0 and 1.5%) of punicic acid in the diets. After 12weeks of feeding the hens, eggs collection began. Sixty eggs - randomly selected from each group - were analysed for physicochemical properties. Eggs naturally enriched with CLnA preserve their composition and conventional properties in most of the analysed parameters (including chemical composition, physical as well as organoleptic properties). Dietary CLnA had positive impact on the colour of the eggs' yolk, whereas the hardness of hard-boiled egg yolks was not affected. Additionally, increasing dietary CLnA led to an increase not only the CLnA concentrations, but also CLA in egg-yolk lipids. Copyright © 2016. Published by Elsevier Ltd.

Effects of dietary yeast autolysate (Saccharomyces cerevisiae) on performance, egg traits, egg cholesterol content, egg yolk fatty acid composition and humoral immune response of laying hens.

PubMed

Yalçin, Sakine; Yalçin, Suzan; Cakin, Kemal; Eltan, Onder; Dağaşan, Levent

2010-08-15

The objective of this study was to determine the effects of dietary yeast autolysate on performance, egg traits, egg cholesterol content, egg yolk fatty acid composition, lipid oxidation of egg yolk, some blood parameters and humoral immune response of laying hens during a 16 week period. A total of 225 Hyline Brown laying hens, 22 weeks of age, were allocated equally to one control group and four treatment groups. Yeast autolysate (Saccharomyces cerevisiae, InteWall) was used at levels of 1, 2, 3 and 4 g kg(-1) in the diets of the first, second, third and fourth treatment groups respectively. Dietary treatments did not significantly affect body weight, feed intake and egg traits. Yeast autolysate supplementation increased egg production (P < 0.001) and egg weight (P < 0.001) and improved feed efficiency (P < 0.05). Yeast autolysate at levels of 2, 3 and 4 g kg(-1) decreased egg yolk cholesterol level as mg g(-1) yolk (P < 0.01) and blood serum levels of cholesterol and triglyceride (P < 0.05) and increased antibody titres to sheep red blood cells (P < 0.01). Total saturated fatty acids and the ratio of saturated/unsaturated fatty acids increased (P < 0.01) and total monounsaturated fatty acids (P < 0.001) decreased with yeast autolysate supplementation. Dietary yeast autolysate at levels of 2, 3 and 4 g kg(-1) had beneficial effects on performance, egg cholesterol content and humoral immune response. It is concluded that 2 g kg(-1) yeast autolysate will be enough to have beneficial effects in laying hens. Copyright (c) 2010 Society of Chemical Industry.

Effects of dietary protein levels during rearing and dietary energy levels during lay on body composition and reproduction in broiler breeder females.

PubMed

van Emous, R A; Kwakkel, R P; van Krimpen, M M; Hendriks, W H

2015-05-01

A study with a 2 × 3 × 2 factorial arrangement was conducted to determine the effects of 2 dietary protein levels (high = CPh and low = CPl) during rearing, 3 dietary energy levels (3,000, MEh1; 2,800, MEs1; and 2,600, MEl1, kcal/kg AMEn, respectively) during the first phase of lay, and 2 dietary energy levels (2,800, MEs2; and 3,000, MEh2, kcal/kg AMEn, respectively) during the second phase of lay on body composition and reproduction in broiler breeders. No meaningful interactions for energy and protein treatments within the different phases of the study were found and, therefore, this paper focusses on the main effects. Pullets fed the CPl diet had a 12.8% higher feed intake, 14% lower breast muscle, and 97% higher abdominal fat pad portion at 22 wk age. The increased abdominal fat pad and decreased breast muscle of the CPl compared to the CPh birds increased hatchability during the first phase of lay, due to a decreased embryonic mortality between d 10 to 21 of incubation, and increased egg production during the second phase of lay. Feeding birds the MEh1 and MEl1 diets slightly decreased egg production compared to the MEs1 birds. Birds fed the MEh1 diet showed a higher mortality compared to the birds fed the MEs1 and MEl1 diets. Feeding birds the MEh2 diet did not affect egg production, increased hatchability of fertile eggs, decreased embryonic mortality between d 3 to 21 of incubation, and increased the number of first-grade chicks. It was concluded that a low-protein diet during rearing changed body composition with positive effects on incubation traits during the first phase of lay and improved egg production during the second phase of lay in broiler breeders. A high-energy or low-energy diet compared to a standard diet during the first phase of lay slightly decreased total and settable egg numbers while a high-energy diet during the second phase of lay increased hatchability and number of saleable chicks. © 2015 Poultry Science Association Inc.

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.

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

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.

Environmental CO2 inhibits Caenorhabditis elegans egg-laying by modulating olfactory neurons and evokes widespread changes in neural activity

PubMed Central

Fenk, Lorenz A.; de Bono, Mario

2015-01-01

Carbon dioxide (CO2) gradients are ubiquitous and provide animals with information about their environment, such as the potential presence of prey or predators. The nematode Caenorhabditis elegans avoids elevated CO2, and previous work identified three neuron pairs called “BAG,” “AFD,” and “ASE” that respond to CO2 stimuli. Using in vivo Ca2+ imaging and behavioral analysis, we show that C. elegans can detect CO2 independently of these sensory pathways. Many of the C. elegans sensory neurons we examined, including the AWC olfactory neurons, the ASJ and ASK gustatory neurons, and the ASH and ADL nociceptors, respond to a rise in CO2 with a rise in Ca2+. In contrast, glial sheath cells harboring the sensory endings of C. elegans’ major chemosensory neurons exhibit strong and sustained decreases in Ca2+ in response to high CO2. Some of these CO2 responses appear to be cell intrinsic. Worms therefore may couple detection of CO2 to that of other cues at the earliest stages of sensory processing. We show that C. elegans persistently suppresses oviposition at high CO2. Hermaphrodite-specific neurons (HSNs), the executive neurons driving egg-laying, are tonically inhibited when CO2 is elevated. CO2 modulates the egg-laying system partly through the AWC olfactory neurons: High CO2 tonically activates AWC by a cGMP-dependent mechanism, and AWC output inhibits the HSNs. Our work shows that CO2 is a more complex sensory cue for C. elegans than previously thought, both in terms of behavior and neural circuitry. PMID:26100886

Low-fiber alfalfa (Medicago sativa L.) meal in the laying hen diet: effects on productive traits and egg quality.

PubMed

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

2014-07-01

This study was designed to determine the effects on laying performance and egg quality resulting from partial substitution of soybean meal (SBM) with low-fiber alfalfa (LFA; Medicago sativa L.) meal in the diet of early-phase laying hens. ISA Brown layers, 18 wk of age, were randomly allocated to 2 dietary treatments and fed for 10 wk. The hens were fed 2 wheat middling-based diets: a control diet, which contained SBM (15% of diet), and a test diet containing LFA (15% of diet) as the main protein source. Low-fiber alfalfa meal was obtained by a combination of sieving and air-classification processes. Feed intake was recorded daily, and egg production was calculated on a hen-day basis; eggs from each group were weekly collected to evaluate egg components and quality. The partial substitution of SBM with LFA had no adverse effect on growth performance of early-phase laying hens. Egg production and none of the egg-quality traits examined were influenced by dietary treatment, except for yolk color (P < 0.001) and yolk percentage (P < 0.05) as well as yolk cholesterol and β-carotene contents (P < 0.001), which were improved in hens fed the LFA diet. Including LFA increased serum β-carotene and reduced serum cholesterol concentrations (P < 0.001). Our results suggest that partially replacing conventional SBM as protein source with low-fiber alfalfa meal in the laying-hen diet can positively influence yolk quality without adversely affecting productive traits. © 2014 Poultry Science Association Inc.

Reproductive queue without overt conflict in the primitively eusocial wasp Ropalidia marginata

PubMed Central

Bang, Alok; Gadagkar, Raghavendra

2012-01-01

Colonies of the primitively eusocial wasp Ropalidia marginata consist of a single egg layer (queen) and a number of non–egg-laying workers. Although the queen is a docile individual, not at the top of the behavioral dominance hierarchy of the colony, she maintains complete reproductive monopoly. If the queen is lost or removed, one and only one of the workers [potential queen (PQ)] becomes hyperaggressive and will become the next queen of the colony. The PQ is almost never challenged because she first becomes hyperaggressive and then gradually loses her aggression, develops her ovaries, and starts laying eggs. Although we are unable to identify the PQ when the queen is present, she appears to be a “cryptic heir designate.” Here, we show that there is not just one heir designate but a long reproductive queue and that PQs take over the role of egg-laying, successively, without overt conflict, as the queen or previous PQs are removed. The dominance rank of an individual is not a significant predictor of its position in the succession hierarchy. The age of an individual is a significant predictor, but it is not a perfect predictor because PQs often bypass older individuals to become successors. We suggest that such a predesignated reproductive queue that is implemented without overt conflict is adaptive in the tropics, where conspecific usurpers from outside the colony, which can take advantage of the anarchy prevailing in a queenless colony and invade it, are likely to be present throughout the year. PMID:22908278

Egg-laying butterflies distinguish predaceous ants by sight.

PubMed

Sendoya, Sebastián F; Freitas, André V L; Oliveira, Paulo S

2009-07-01

Information about predation risks is critical for herbivorous insects, and natural selection favors their ability to detect predators before oviposition and to select enemy-free foliage when offspring mortality risk is high. Food plants are selected by ovipositing butterflies, and offspring survival frequently varies among plants because of variation in the presence of predators. Eunica bechina butterflies oviposit on Caryocar brasiliense, an ant-defended plant. Experiments with dried Camponotus and Cephalotes ants pinned to leaves revealed that butterflies use ant size and form as visual cues to avoid ovipositing on plant parts occupied by ants more likely to kill larval offspring. Presence of sap-sucking bugs did not affect butterfly oviposition. This is the first demonstration that visual recognition of predators can mediate egg-laying decisions by an insect herbivore and that an insect will discriminate among different species of potential predators. This unusual behavioral capability permits specialization on a risky, ant-defended food plant.

Egg-laying substrate selection for optimal camouflage by quail.

PubMed

Lovell, P George; Ruxton, Graeme D; Langridge, Keri V; Spencer, Karen A

2013-02-04

Camouflage is conferred by background matching and disruption, which are both affected by microhabitat. However, microhabitat selection that enhances camouflage has only been demonstrated in species with discrete phenotypic morphs. For most animals, phenotypic variation is continuous; here we explore whether such individuals can select microhabitats to best exploit camouflage. We use substrate selection in a ground-nesting bird (Japanese quail, Coturnix japonica). For such species, threat from visual predators is high and egg appearance shows strong between-female variation. In quail, variation in appearance is particularly obvious in the amount of dark maculation on the light-colored shell. When given a choice, birds consistently selected laying substrates that made visual detection of their egg outline most challenging. However, the strategy for maximizing camouflage varied with the degree of egg maculation. Females laying heavily maculated eggs selected the substrate that more closely matched egg maculation color properties, leading to camouflage through disruptive coloration. For lightly maculated eggs, females chose a substrate that best matched their egg background coloration, suggesting background matching. Our results show that quail "know" their individual egg patterning and seek out a nest position that provides most effective camouflage for their individual phenotype. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

Effect of laying sequence on egg mercury in captive zebra finches: an interpretation considering individual variation.

PubMed

Ou, Langbo; Varian-Ramos, Claire W; Cristol, Daniel A

2015-08-01

Bird eggs are used widely as noninvasive bioindicators for environmental mercury availability. Previous studies, however, have found varying relationships between laying sequence and egg mercury concentrations. Some studies have reported that the mercury concentration was higher in first-laid eggs or declined across the laying sequence, whereas in other studies mercury concentration was not related to egg order. Approximately 300 eggs (61 clutches) were collected from captive zebra finches dosed throughout their reproductive lives with methylmercury (0.3 μg/g, 0.6 μg/g, 1.2 μg/g, or 2.4 μg/g wet wt in diet); the total mercury concentration (mean ± standard deviation [SD] dry wt basis) of their eggs was 7.03 ± 1.38 μg/g, 14.15 ± 2.52 μg/g, 26.85 ± 5.85 μg/g, and 49.76 ± 10.37 μg/g, respectively (equivalent to fresh wt egg mercury concentrations of 1.24 μg/g, 2.50 μg/g, 4.74 μg/g, and 8.79 μg/g). The authors observed a significant decrease in the mercury concentration of successive eggs when compared with the first egg and notable variation between clutches within treatments. The mercury level of individual females within and among treatments did not alter this relationship. Based on the results, sampling of a single egg in each clutch from any position in the laying sequence is sufficient for purposes of population risk assessment, but it is not recommended as a proxy for individual female exposure or as an estimate of average mercury level within the clutch. © 2015 SETAC.

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.

Nutrient reserve dynamics of breeding canvasbacks

USGS Publications Warehouse

Barzen, Jeb A.; Serie, Jerome R.

1990-01-01

We compared nutrients in reproductive and nonreproductive tissues of breeding Canvasbacks (Aythya valisineria) to assess the relative importance of endogenous reserves and exogenous foods. Fat reserves of females increased during rapid follicle growth and varied more widely in size during the early phase of this period. Females began laying with ca. 205 g of fat in reserve and lost 1.8 g of carcass fat for every 1 g of fat contained in their ovary and eggs. Females lost body mass (primarily fat) at a declining rate as incubation advanced. Protein reserves increased directly with dry oviduct mass during rapid follicle growth. This direct relationship was highly dependent upon data from 2 birds and likely biased by structural size. During laying, protein reserves did not vary with the combined mass of dry oviduct and dry egg protein. Between laying and incubation, mean protein reserves decreased by an amount equal to the protein found in 2.1 Canvasback eggs. Calcium reserves did not vary with the cumulative total of calcium deposited in eggs. Mean calcium reserve declined by the equivalent content of 1.2 eggs between laying and incubation. We believe that protein and calcium were stored in small amounts during laying, and that they were supplemented continually by exogenous sources. In contrast, fat was stored in large amounts and contributed significantly to egg production and body maintenance. Male Canvasbacks lost fat steadily-but not protein or calcium-as the breeding season progressed.

A cuckoo-like parasitic moth leads African weaver ant colonies to their ruin

PubMed Central

Dejean, Alain; Orivel, Jérôme; Azémar, Frédéric; Hérault, Bruno; Corbara, Bruno

2016-01-01

In myrmecophilous Lepidoptera, mostly lycaenids and riodinids, caterpillars trick ants into transporting them to the ant nest where they feed on the brood or, in the more derived “cuckoo strategy”, trigger regurgitations (trophallaxis) from the ants and obtain trophic eggs. We show for the first time that the caterpillars of a moth (Eublemma albifascia; Noctuidae; Acontiinae) also use this strategy to obtain regurgitations and trophic eggs from ants (Oecophylla longinoda). Females short-circuit the adoption process by laying eggs directly on the ant nests, and workers carry just-hatched caterpillars inside. Parasitized colonies sheltered 44 to 359 caterpillars, each receiving more trophallaxis and trophic eggs than control queens. The thus-starved queens lose weight, stop laying eggs (which transport the pheromones that induce infertility in the workers) and die. Consequently, the workers lay male-destined eggs before and after the queen’s death, allowing the colony to invest its remaining resources in male production before it vanishes. PMID:27021621

Increasing persistency in lay and stabilising egg quality in longer laying cycles. What are the challenges?

PubMed Central

Bain, M. M.; Nys, Y.; Dunn, I.C.

2016-01-01

Abstract In the past 50 years, selection starting initially at the breed level and then using quantitative genetics coupled with a sophisticated breeding pyramid, has resulted in a very productive hybrid for a variety of traits associated with egg production.One major trait currently being developed further is persistency of lay and the concept of the “long life” layer. Persistency in lay however cannot be achieved without due consideration of how to sustain egg quality and the health and welfare of the birds in longer laying cycles. These multiple goals require knowledge and consideration of the bird’s physiology, nutritional requirements, which vary depending on age and management system, reproductive status and choice of the selection criteria applied.The recent advent of molecular genetics offers considerable hope that these multiple elements can be balanced for the good of all in the industry including the hens.The “long life” layer, which will be capable of producing 500 eggs in a laying cycle of 100 weeks, is therefore on the horizon, bringing with it the benefits of a more efficient utilisation of diminishing resources, including land, water, raw materials for feed as well as a reduction in waste, and an overall reduced carbon footprint. PMID:26982003

Increasing persistency in lay and stabilising egg quality in longer laying cycles. What are the challenges?

PubMed

Bain, M M; Nys, Y; Dunn, I C

2016-06-01

In the past 50 years, selection starting initially at the breed level and then using quantitative genetics coupled with a sophisticated breeding pyramid, has resulted in a very productive hybrid for a variety of traits associated with egg production. One major trait currently being developed further is persistency of lay and the concept of the "long life" layer. Persistency in lay however cannot be achieved without due consideration of how to sustain egg quality and the health and welfare of the birds in longer laying cycles. These multiple goals require knowledge and consideration of the bird's physiology, nutritional requirements, which vary depending on age and management system, reproductive status and choice of the selection criteria applied. The recent advent of molecular genetics offers considerable hope that these multiple elements can be balanced for the good of all in the industry including the hens. The "long life" layer, which will be capable of producing 500 eggs in a laying cycle of 100 weeks, is therefore on the horizon, bringing with it the benefits of a more efficient utilisation of diminishing resources, including land, water, raw materials for feed as well as a reduction in waste, and an overall reduced carbon footprint.

Stress induced by heavy metals on breeding of magpie (Pica pica) from central Iran.

PubMed

Zarrintab, Mohammad; Mirzaei, Rouhollah

2017-09-01

The aim of this study was to address the impacts of some heavy metals (Cd, Pb, Zn, Ni and Cu) contamination on laying behavior, egg quality and breeding performance of Pica pica in north of Isfahan Province, Iran. During the breeding season of 2013, magpie's egg content and eggshell as well as nestling excrements and feathers were collected and total concentrations of heavy metals were measured by ICP-OES. Except for Zn in nestling feathers, the significantly higher concentrations of heavy metals were observed in nestling excrements than other samples. Also, comparison of heavy metals concentrations in egg content and eggshell showed that egg content had significantly higher concentrations of Zn and Pb, instead eggshell had significantly higher amount of Cu and Cd. Except for Cu, all heavy metals concentrations in eggshell had a negative relationship with morphological characters; and also concentration of Cu in egg content showed a significantly negative correlation with egg weight and volume. The most of heavy metals in nestling feathers and excrements had strongly positive correlations with each other. Also all heavy metals levels in eggshell and egg content had significantly positive correlations (except for Cu). Unhatched eggs had significantly lower weight but also greater levels of Zn, Cd, and Pb, than randomly collected eggs. No significant differences were observed for morphometric measurements of eggs between different sites, however, a decreased gradient was observed in egg volume toward the brick kiln site. Samples collected in brick kiln site accumulated higher concentrations of heavy metals than other sites. Although numbers of clutch size in brick kiln site were significantly higher than other sites, however, other breeding variable were lower than other sites. It can be suggested that ecosystem contamination may be caused to decrease the reproduction rate of Pica pica in brick kiln, probably by laying more poor quality eggs per clutch and nestling mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

IgY Technology: Extraction of Chicken Antibodies from Egg Yolk by Polyethylene Glycol (PEG) Precipitation

PubMed Central

Pauly, Diana; Chacana, Pablo A.; Calzado, Esteban G.; Brembs, Björn; Schade, Rüdiger

2011-01-01

Hens can be immunized by means of i.m. vaccination (Musculus pectoralis, left and right, injection volume 0.5-1.0 ml) or by means of Gene-Gun plasmid-immunization. Dependent on the immunogenicity of the antigen, high antibody-titres (up to 1:100,000 - 1:1,000,000) can be achieved after only one or 3 - 4 boost immunizations. Normally, a hen lays eggs continuously for about 72 weeks, thereafter the laying capacity decreases. This protocol describes the extraction of total IgY from egg yolk by means of a precipitation procedure (PEG. Polson et al. 1980). The method involves two important steps. The first one is the removal of lipids and the second is the precipitation of total IgY from the supernatant of step one. After dialysis against a buffer (normally PBS) the IgY-extract can be stored at -20°C for more than a year. The purity of the extract is around 80 %, the total IgY per egg varies from 40-80 mg, dependent on the age of the laying hen. The total IgY content increases with the age of the hen from around 40 mg/egg up to 80 mg/egg (concerning PEG precipitation). The laying capacity of a hen per year is around 325 eggs. That means a total potential harvest of 20 g total IgY/year based on a mean IgY content of 60 mg total IgY/egg (see Table 1). PMID:21559009

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.

Peptide supplementation to nutrient-adequate diets enhanced internal egg quality during storage in hens at peak production.

PubMed

Olukosi, Oluyinka A; Xiao, Weiwei; Jia, Jing

2018-03-01

There is paucity of information on the use of dietary peptides in laying hens and its effects on egg production and quality. In the current study, peptide from enzymatic hydrolysis of soybean protein was incorporated into laying hens' diets to investigate its effect on egg production and internal egg quality. There were no treatment effects on egg production (average hen day production was 96%) during the experiment. Final body weight of the hens increased quadratically (P < 0.05) in response to peptide supplementation. There were no significant effects of peptide supplementation on internal egg quality of the fresh eggs. Peptide supplementation tended to increase yolk colour (P < 0.10) in eggs collected at 4 weeks of the study and stored at room temperature for 14 days. For the eggs collected at 8 weeks of the experiment and stored at room temperature for 14 days, peptide supplementation linearly increased (P < 0.05) albumen height, Haugh unit and yolk index but linearly decreased (P < 0.01) yolk width. Peptide supplementation to laying hens at peak production, receiving diets meeting their nutrient requirement, did not improve hen production but positively helped to maintain hens' body weight and egg quality during storage. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Dietary Wolffia arrhiza meal as a substitute for soybean meal: its effects on the productive performance and egg quality of laying Japanese quails.

PubMed

Suppadit, Tawadchai; Jaturasitha, Sanchai; Sunthorn, Napassawan; Poungsuk, Pukkapong

2012-10-01

Wolffia arrhiza meal (WAM) was evaluated as a protein replacement for soybean meal (SBM) in the diet of laying Japanese quails. A total of 480 4-week-old laying quails were randomly allocated to form six groups in a completely randomized design. Each group contained four replicates, with 20 quails per replicate. WAM was incorporated into the diets at levels of 0, 4.00, 8.00, 12.0, 16.0 and 20.0%. The results showed that feed intake per bird per day, daily egg-laying rate, feed cost per 100 egg weight, egg width, egg length, egg weight, eggshell thickness, yolk height and shell quality characteristics in terms of breaking time, Young's modulus, work, maximum force, fracturability, breaking stress, stiffness and power showed no statistically significant differences (P > 0.05) among the 0 to 16.0% levels of WAM. However, these performance measures were significantly lower with 20.0% WAM in the formulated ration (P < 0.05). Mortality showed no significant differences among dietary treatments (P > 0.05). The color intensity of the yolk increased as SBM was replaced with increasing amounts of WAM (P < 0.05). In conclusion, WAM could be successfully used in place of SBM. However, the amount used should not exceed 16.0%.

Egg size and laying order of snowy egrets, great egrets, and black-crowned night-herons

USGS Publications Warehouse

Custer, T.W.; Frederick, P.C.

1990-01-01

The nesting biology of the family Ardeidae (bitterns, herons, and egrets) has been intensively studied (e.g., Owen 1960, Milstein et al. 1970, Werschkul 1979), but egg size in relation to laying order bas not received attention. The last egg laid in gull and tern clutches is generally smaller than preceding eggs (e.g., Parsons 1970, Nisbet 1978). The relative size of the final egg in a clutch decreases with increased body size among bird species and this relationship may be correlated with an increased brood-reduction strategy (Slagsvold et al. 1984). Relative egg size could be an important component to brood reduction, because egg size can affect subsequent survival of young (Parsons 1970, Nisbet 1978, Lundberg and Vaisanen 1979).

Microbiological Consequences of Different Housing Systems for Laying Hens: Field and Experimental Infection Studies

USDA-ARS?s Scientific Manuscript database

A significant proportion of human illnesses caused by Salmonella are linked to the consumption of contaminated eggs. In response, substantial government and private industry resources are committed to comprehensive Salmonella testing and risk reduction programs for commercial egg-laying flocks. Envi...

Salmonella Enteritidis Deposition inside Eggs after Experimental Infection of Laying Hens with Different Oral Doses

USDA-ARS?s Scientific Manuscript database

The continuing attribution of human Salmonella Enteritidis infections to internally contaminated eggs has necessitated the commitment of substantial public and private resources to risk reduction and testing programs for commercial laying flocks. Cost-effective risk reduction requires a detailed und...

Relationships between yolk androgens and nest density, laying date, and laying order in Western Burrowing Owls (Athene cunicularia hypugaea)

USGS Publications Warehouse

Welty, J.L.; Belthoff, J.R.; Egbert, J.; Schwabl, H.

2012-01-01

Increases in yolk androgens within and among avian clutches have been correlated with decreased incubation time, increased aggression within a nest, increased begging behaviour, decreased immune response, and decreased life span. Although the mechanisms that lead to variability in yolk androgens within and between clutches are not completely known, yolk androgens can be a function of both social and environmental conditions. We were interested in if and how nesting density, laying date, and laying order influenced yolk androgens in Western Burrowing Owls (Athene cunicularia hypugaea (Bonaparte, 1825)) in which nest density varies considerably. In 2006 and 2007, we used radioimmunoassay to quantify the concentrations of testosterone, 5a-dihydrotestosterone, and androstenedione in the egg yolks from one early and one latelaid egg in 47 nests of Burrowing Owls located in the Morley Nelson Snake River Birds of Prey National Conservation Area in southern Idaho. Nesting density had no detectable effect on yolk androgens. Yolk androgens varied temporally and peaked in the middle of the laying season while being low before and after this time period. Within nests, late-laid eggs had higher testosterone and dihydrotestosterone than early-laid eggs; adrostendione exhibited a similar pattern in one but not both years of our study. It is possible that the seasonal pattern in yolk androgens that we observed is related to aspects of mate quality for females or declining chances of fledging success for later nesting females, whereas rises in egg androgens between early and late eggs within clutches could reflect a mechanism to assist nestlings from late-laid eggs that hatch one to several days after their siblings to better compete for resources within the nest or promote survival in the presence of larger siblings.

Apoptosis induction and release of inflammatory cytokines in the oviduct of egg-laying hens experimentally infected with H9N2 avian influenza virus.

PubMed

Wang, Jingyu; Tang, Chao; Wang, Qiuzhen; Li, Ruiqiao; Chen, Zhanli; Han, Xueying; Wang, Jing; Xu, Xingang

2015-06-12

The H9N2 subtype avian influenza virus (AIV) can cause serious damage to the reproductive tract of egg-laying hens, leading to severe egg-drop and poor egg shell quality. However, previous studies in relation to the oviductal-dysfunction resulted from this agent have not clearly been elucidated. In this study, apoptosis and pathologic changes in the oviducts of egg-laying hens caused by H9N2 AIV were evaluated. To understand the immune response in the pathogenic processes, 30-week old specific pathogen free (SPF) egg-laying hens inoculated with H9N2 subtype of AIV through combined intra-ocular and intra-nasal routes. H9N2 AIV infection resulted in oviductal lesions, triggered apoptosis and expression of immune related genes accompanied with infiltration of CD3(+)CD4(+) and CD3(+)CD8α(+) cells. Significant tissue damage and apoptosis were observed in the five oviductal parts (infundibulum, magnum, isthmus, uterus and vagina) at 5 days post-inoculation (dpi). Furthermore, immune-related genes, including chicken TLR3 (7, 21), MDA5, IL-2, IFN-β, CXCLi1, CXCLi2, XCL1, XCR1 and CCR5 showed variation in the egg-laying hens infected with H9N2 AIV. Notably, mRNA expression of IFN-α was suppressed during the infection. These results show distinct expression patterns of inflammatory cytokines and chemokines amongst segments of the oviduct. Differential gene expression of inflammatory cytokines and lymphocytes aggregation occurring in oviducts may initiate the infected tissue in response to virus replication which may eventually lead to excessive cellular apoptosis and tissue damage. Copyright © 2015 Elsevier B.V. All rights reserved.

Digestibility, productive performance, and egg quality of laying hens as affected by dried cassava pulp replacement with corn and enzyme supplementation.

PubMed

Khempaka, Sutisa; Maliwan, Prapot; Okrathok, Supattra; Molee, Wittawat

2018-02-24

Two experiments were conducted to investigate the potential use of dried cassava pulp (DCP) supplemented with enzymes as an alternative feed ingredient in laying hen diets. In experiment 1, 45 laying hens (Isa Brown) aged 45 weeks were placed in individual cages to measure nutrient digestibility for 10 days. Nine dietary treatments were control and DCP as a replacement for corn at 20, 25, 30, and 35% supplemented with mixed enzymes (cellulase, glucanase, and xylanase) at 0.10 and 0.15%. Results showed that the use of DCP at 20-35% added with mixed enzymes had no negative effects on dry matter digestibility, while organic matter digestibility and nitrogen retention decreased with increased DCP up to 30-35% in diets. Both enzyme levels (0.10 and 0.15%) showed similar results on nutrient digestibility and retention. In experiment 2, a total of 336 laying hens aged 32 weeks were randomly allocated to seven dietary treatments (control and DCP-substituted diets at 20, 25, and 30%) supplemented with mixed enzymes (0.10 and 0.15%). Diets incorporated with 20-30% of DCP and supplemented with mixed enzymes at both levels had no significant effects on egg production, egg weight, feed intake, egg mass, feed conversion ratio, protein efficiency ratio, or egg quality, except for egg yolk color being decreased with an increase of DCP in diets (P < 0.05). In conclusion, it is suggested that DCP supplemented with enzymes can be used as an energy source in laying hen diets up to 30% without showing negative effects on nutrient digestibility, productive performance, or egg quality.

Use of guar by-products in high-production laying hen diets.

PubMed

Gutierrez, O; Zhang, C; Cartwright, A L; Carey, J B; Bailey, C A

2007-06-01

A 5x5 Latin square experiment was conducted to evaluate the effect of feeding low concentrations of guar germ or a combination of guar germ and hull (guar meal) in high-production laying hen diets. A total of 125 Lohmann laying hens (21 wk old) of similar BW were randomly assigned to 5 blocks. Each block was divided into 5 experimental units, consisting of 5 hens per unit. Hens were fed either a nonguar control diet, or 1 of 4 diets containing either 2.5 or 5% guar germ, or 2.5 or 5% guar meal over a 20-wk trial period (five 4-wk periods). No significant differences were observed when feeding either 2.5 or 5% guar germ or meal (P>0.05) on hen-day egg production or feed consumption. Significant differences in egg weight, total egg mass per hen, and feed conversion ratio were detected in hens fed 2.5% guar meal, whereas they remained unchanged for diets containing either level of guar germ or 5% guar meal. Feeding either level of guar germ or guar meal did not affect shell quality (shell thickness, egg breaking force, and specific gravity), Haugh units, or egg yolk color (L*, a*, b*). The results showed that both guar germ and guar meal can be fed to high-production laying hens at up to 5% without adverse effects on laying hen performance.

Effect of level of fiber of the rearing phase diets on egg production, digestive tract traits, and body measurements of brown egg-laying hens fed diets differing in energy concentration.

PubMed

Guzmán, P; Saldaña, B; Bouali, O; Cámara, L; Mateos, G G

2016-08-01

This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied. © 2016 Poultry Science Association Inc.

Use of L-carnitine and humate in laying quail diets.

PubMed

Yalçin, Sakine; Ergün, A; Erol, Handan; Yalçin, Suzan; Ozsoy, B

2005-01-01

This experiment was carried out to determine the effects of using L-carnitine and humate alone or in combination in quail diets on laying performance, egg traits and blood parameters. A total of 280 Japanese quails aged 10 weeks, divided into one control group and three treatment groups, were used. The diets of the first, second and third treatment groups were supplemented with 100 mg L-carnitine/kg, 1.5 g humate (Farmagülatör Dry Plus)/kg and 100 mg L-camitine + 1.5 g humate/kg, respectively. The experimental period lasted 16 weeks. The addition of L-carnitine and sodium humate alone or in combination did not significantly affect body weight, feed consumption, egg production, feed conversion ratio, mortality, egg-shell thickness, egg yolk index and the percentages of egg-shell, albumen and yolk. Egg weight increased (P < 0.001) with L-carnitine supplementation. The values of egg albumen height (P < 0.05), egg albumen index (P < 0.01) and egg Haugh unit (P < 0.05) were increased with humate supplementation. Egg cholesterol content and blood serum parameters were not affected by the supplementation of L-carnitine with or without humate. The results in this study demonstrated that L-carnitine supplementation increased egg weight while humate addition increased egg albumen index and egg Haugh unit of laying quails. However, the combined administration of L-carnitine and humate did not have any significant effects on the parameters measured.

Salmonella Enteritidis deposition in eggs after experimental infection of laying hens with different oral doses

USDA-ARS?s Scientific Manuscript database

The continuing attribution of human Salmonella Enteritidis (SE) infections to internally contaminated eggs has necessitated the commitment of substantial public and private resources to SE testing and control programs in commercial laying flocks. Cost-effective risk reduction requires a detailed and...

Variation in incubation periods and egg metabolism in mallards: Intrinsic mechanisms to promote hatch synchrony

USGS Publications Warehouse

MacCluskie, Margaret C.; Flint, Paul L.; Sedinger, James S.

1997-01-01

We investigated factors affecting incubation time and metabolic rates of Mallard (Anas platyrhynchos) eggs incubated under constant environmental conditions. Time required to reach the star-pipped stage of hatch varied significantly among females, but not with laying sequence or egg size. Metabolic rate of eggs varied positively with position in the laying sequence and tended to vary among females. Metabolic rate did not vary with egg volume or incubation length. Our results indicate metabolic rate may act as one synchronization mechanism for hatch. The role of maternal effects in development time should be considered in subsequent studies of incubation time in ducks.

C. elegans multi-dendritic sensory neurons: morphology and function

PubMed Central

Albeg, Adi; Smith, Cody; Chatzigeorgiou, Marios; Feitelson, Dror G.; Hall, David H.; Schafer, William R.; Miller, David M.; Treinin, Millet

2010-01-01

PVD and FLP sensory neurons envelope the body of the C. elegans adult with a highly branched network of thin sensory processes. Both PVD and FLP neurons are mechanosensors. PVD is known to mediate the response to high threshold mechanical stimuli. Thus PVD and FLP neurons are similar in both morphology and function to mammalian nociceptors. To better understand the function of these neurons we generated strains lacking them. Behavioral analysis shows that PVD and FLP regulate movement under normal growth conditions, as animals lacking these neurons demonstrate higher dwelling behavior. In addition, PVD—whose thin branches project across the body-wall muscles—may have a role in proprioception, as ablation of PVD leads to defective posture. Moreover, movement-dependent calcium transients are seen in PVD, a response that requires MEC-10, a subunit of the mechanosensory DEG/ENaC channel that is also required for maintaining wild-type posture. Hence, PVD senses both noxious and innocuous signals to regulate C. elegans behavior, and thus combines the functions of multiple mammalian somatosensory neurons. Finally, strong mechanical stimulation leads to inhibition of egg-laying, and this response also depends on PVD and FLP neurons. Based on all these results we suggest that noxious signals perceived by PVD and FLP promote an escape behavior consisting of increased speed, reduced pauses and reversals, and inhibition of egg-laying. PMID:20971193

Mercury patterns in wood duck eggs from a contaminated reservoir in South Carolina, USA.

PubMed

Kennamer, Robert A; Stout, Jason R; Jackson, Brian P; Colwell, Sheila V; Brisbin, I Lehr; Burger, Joanna

2005-07-01

Mercury contamination of wildlife populations has been documented widely in recent years as biomonitoring has become an important tool for assessing environmental contamination. Avian eggs provide an ideal assay material for Hg biomonitoring, particularly when the collection of eggs is simplified by using cavity-nesting species that nest in easily monitored nest boxes. However, studies are needed that address the dynamics of how Hg is distributed within eggs, and how Hg is deposited naturally within clutches laid by a single female and among clutches laid by different females occupying the same contaminated environment. We collected 138 eggs from 13 complete clutches of box-nesting wood ducks (Aix sponsa) during 1991 and 1992 at a contaminated reservoir of the U.S. Department of Energy's Savannah River Site in South Carolina, USA. Total Hg residues in egg components and clutches were determined, partitioning of Hg among egg components was examined, and effects of egg-laying sequence on egg component Hg levels were determined. Mean albumen Hg was 0.22 ppm wet mass, mean yolk Hg was 0.04 ppm, and mean shell Hg was 0.03 ppm. On average, 86.1% of total egg Hg was concentrated in the albumen, 11.2% in the yolk, and 2.7% in the shell. Mercury concentrations in all egg components varied significantly among clutches and between successive clutches laid by the same female in the same year. Laying sequence significantly affected Hg concentrations in the albumen and shell, but not in the yolk. Declines of albumen Hg due to laying sequence were more pronounced for clutches that contained higher average Hg levels. Our results suggest that collection of first-laid eggs may be preferable for assessing maximal Hg exposure to developing embryos, and that monitoring Hg levels through the use of empty eggshells following brood departure from nests may be valid only if the laying sequence is known.

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.

Does egg colouration reflect male condition in birds?

NASA Astrophysics Data System (ADS)

Martínez-Padilla, Jesús; Dixon, Heather; Vergara, Pablo; Pérez-Rodríguez, Lorenzo; Fargallo, Juan A.

2010-05-01

How colouration provides information about individuals in birds has been a central issue in recent decades. Although much information has been derived, little is known about the adaptive significance of egg colouration in birds. A recent idea suggests that biliverdin- and porphyrin-pigmented eggs may act as a post-mating sexual signal for males to assess female quality. In birds, it is common for males to influence prelaying female condition by courtship feeding. Using Eurasian kestrels, a species that lays protoporphyrin-pigmented eggs, we descriptively assessed the influence of male feeding on egg pigmentation by considering female phenotype, condition, breeding parameters and male body condition. We found that older females and females with greyer tails (an index of individual quality) produce highly pigmented eggs. However, male body condition was the only variable that explained egg colouration when considered together with the female-related variables. Therefore, females that mated with males in better condition laid highly pigmented eggs. With the same species, we also explored the cost of producing protoporphyrin-pigmented eggs using a food-supply experiment before the laying period. Food supplementation did not increase egg pigmentation, but hatching success and egg mass were positively related to egg colouration only in food supplied pairs. We suggest that egg colouration might be costly to produce and probably suggests egg quality. However, this cost cannot be explained by female quality, but by male condition instead. In general, our results do not support the theory that egg colouration is a post-mating sexual signal in species where males determine female condition at the time of laying.

Effects of the novel anthelmintic emodepside on the locomotion, egg-laying behaviour and development of Caenorhabditis elegans.

PubMed

Bull, Kathryn; Cook, Alan; Hopper, Neil A; Harder, Achim; Holden-Dye, Lindy; Walker, Robert J

2007-05-01

Emodepside, a cyclooctadepsipeptide, is a broad-spectrum anthelmintic previously shown to paralyse body wall muscle and pharyngeal muscle in the model nematode Caenorhabditis elegans. We demonstrate that wild-type C. elegans L4 are less sensitive than adults to emodepside in two independent assays of locomotor behaviour: body bend generation on agar (adult IC(50) 3.7 nM, L4 IC(50) 13.4 nM) and thrashing behaviour in liquid (thrashing behaviour as a % of controls after 1h in 10 microM emodepside: adults 16%, L4 worms 48%). We also show that continuous exposure of wild-type C. elegans to emodepside throughout the life-cycle from egg onwards, slows worm development, an effect that is emodepside concentration-dependent. The rate of worm-hatching from eggs on agar plates containing emodepside was not significantly different from controls, suggesting that it is development post-hatching rather than hatching itself that is affected by the drug. Emodepside also inhibits wild-type C. elegans egg-laying, with acute exposure to the drug at 500 nM resulting in an almost total inhibition within the first hour. However, the rate of egg production was not inhibited and therefore emodepside-treated worms became bloated with eggs, eventually rupturing. This suggests that the effect of emodepside on reproduction is not due to an inhibition of egg production but rather a paralytic effect on the egg-laying muscles. These results, when coupled with previous research, suggest that emodepside interferes with signalling at the neuromuscular junction on the body-wall muscles (Willson et al., 2003), pharynx (Willson et al., 2004) and egg-laying muscles and thus inhibits three important physiological functions: locomotion, feeding and reproduction.

Feed addition of curcumin to laying hens showed anticoccidial effect, and improved egg quality and animal health.

PubMed

Galli, Gabriela M; Da Silva, Aleksandro S; Biazus, Angelisa H; Reis, João H; Boiago, Marcel M; Topazio, Josué P; Migliorini, Marcos J; Guarda, Naiara S; Moresco, Rafael N; Ourique, Aline F; Santos, Cayane G; Lopes, Leandro S; Baldissera, Matheus D; Stefani, Lenita M

2018-06-01

The aim of this study was to evaluate whether the addition of curcumin in the diet of commercial laying hens could have an anticoccidial action and improve egg quality. For this, 60 laying hens were divided into three groups: T0 (the control group); T30 and T50 (30 and 50 mg/kg of curcumin in the feed, respectively). Eggs recently laid were collected on days 14 and 21 of the experiment, and stored for 21 days. It was observed increased specific gravity and yolk index in stored eggs of the groups T30 and T50 compared to T0. The yolk color reduced in the eggs stored from groups T30 and T50 compared to T0. Moreover, TBARS levels were lower in fresh and stored eggs from groups T30 and T50. It was observed increased TAC levels in fresh eggs from groups T30 and T50 and in stored eggs from the group T50. The presence of curcumin was not detected by HPLC in the yolk and albumen. Seric levels of albumin and uric acid did not differ between groups, while seric levels of total proteins increased on day 21 on groups T30 and T50. Finally, it was observed a significant reduction on the number of oocysts in fecal samples on days 14 and 21 of T30 and T50 compared to T0. Based on these evidences, it is possible to conclude that the addition of curcumin in the diet of laying hens has an anticoccidial effect and improves egg quality. Copyright © 2018 Elsevier Ltd. All rights reserved.

Variability and interaction of some egg physical and eggshell quality attributes during the entire laying hen cycle.

PubMed

Sirri, F; Zampiga, M; Berardinelli, A; Meluzzi, A

2018-05-01

The aim of this study was to investigate the variability and relationships between some egg physical (egg weight, width, length, shape index, and surface area) and eggshell parameters (weight and percentage, thickness, breaking strength, and L*, a*, and b* values) during the entire laying hen cycle. A total of 8,000 eggs was collected every 5 wk, from 30 to 81 wk of hen age (10 samplings of 400 eggs/house), in 2 identical poultry houses equipped with enriched cages. For the statistical analysis, ANOVA, Bivariate Correlation, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis were used. An increase of egg weight, length, and eggshell lightness (L*) associated with a reduction of eggshell percentage, breaking strength, and redness (a*) was observed as the hen aged (P < 0.05). Overall, the coefficients of variation resulted in <5% in width, length, shape index, and egg surface area; from 5 to 10% of egg weight, shell weight, shell percentage, shell thickness, L*, and b*; and >10% of eggshell breaking strength and a*. According to the PCA, the highest changes during the laying cycle are related to egg physical parameters (32%) and to eggshell breaking strength, percentage, and thickness (26%). The egg physical parameters appeared to be strongly correlated to each other, whereas a slight correlation between eggshell breaking strength and color attributes were evidenced (-0.231 and 0.289, respectively, for L* and a*; P < 0.01). Hierarchical cluster analysis, based on principal components of the overall egg attributes, is hereby considered, and evidenced dissimilarities for eggs laid from peak production up for 39 wk of hen age from the eggs laid afterwards. The latter group could also be divided into 2 subgroups, one comprising eggs laid from 44 and 53 wk of hen age and the other from 58 wk to the end. In conclusion, the large dataset created in this study allowed to extrapolate some robust information regarding the variability and correlations of the egg physical and eggshell quality attributes throughout the entire laying hen cycle.

Dietary choline and phospholipid supplementation enhanced docosahexaenoic acid enrichment in egg yolk of laying hens fed a 2% Schizochytrium powder-added diet.

PubMed

Wang, H; Zhang, H J; Wang, X C; Wu, S G; Wang, J; Xu, L; Qi, G H

2017-08-01

The aim of this study was to evaluate the effect of dietary phospholipid supplementation on laying hen performance, egg quality, and the fatty acid profile of egg yolks from hens fed a 2% Schizochytrium powder diet. Three-hundred-sixty 28-wk-old Hy-line W-36 laying hens were randomly allocated to one of the 5 dietary treatments, each treatment with 6 replicates of 12 birds each. All diets included 2% Schizochytrium powder (docosahexaenoic acid [DHA], 137.09 mg/g). The control group was not supplemented with any additional phospholipids, whereas the other 4 experimental diets were supplemented with 1,000 mg/kg choline (CHO), 1,000 mg/kg monoethanolamine (MEA), 1,000 mg/kg lysophosphatidylcholine (LPC), or 500 mg/kg LPC + 500 mg/kg MEA (LPC + MEA). The experimental diets were isocaloric (metabolizable energy, 11.15 MJ/kg) and isonitrogenous (crude protein, 16.60%). The feeding trial lasted 28 days. Laying hen performance and egg quality were not affected (P > 0.05) by the diets used. The monounsaturated fatty acid (MUFA) level was reduced in the LPC group at d 28 (P < 0.01), whereas the polyunsaturated fatty acid (PUFA) level was increased (P < 0.05). The omega-6 (n-6) PUFA level of the egg yolks in the LPC group had a trend to increase in comparison to the control (P = 0.07). The CHO and LPC groups had higher omega-3 (n-3) PUFA and DHA levels and lower n-6/n-3 ratios than the other groups at d 28 (P < 0.01). The DHA content in egg yolk reached a plateau after the laying hens consumed the experimental diets for 14 days, and higher yolk DHA contents were observed in the CHO and LPC groups as compared with the other groups at d 14. It was concluded that dietary choline supplementation for more than 14 d enhanced egg yolk enrichment with n-3 PUFA and DHA when laying hen diets were supplemented with 2% Schizochytrium powder. All the diets had no adverse effect on hen performance, egg quality, or egg components under the experimental condition. © 2017 Poultry Science Association Inc.

Deposition of carotenoids in egg yolk by short-term supplement of coloured carrot (Daucus carota) varieties as forage material for egg-laying hens.

PubMed

Hammershøj, Marianne; Kidmose, Ulla; Steenfeldt, Sanna

2010-05-01

Supplying egg-laying hens with different forage materials may influence egg production and quality. The aim of this study was to examine the short-term effects of standard feed plus 70 g day(-1) per hen of three coloured carrot varieties (orange, yellow and purple) as forage material in comparison with a standard feed control on egg production, egg yolk colour and deposition of carotenoids in the yolk. Carrot supplementation reduced feed intakes significantly, but not on a dry matter basis. Orange carrot treatment significantly reduced egg mass production, whereas yellow and purple carrot treatments did not differ from the control. Egg and yolk weights of all carrot-supplemented treatments were significantly lower than those of the control, but yolk percentages were similar. Yolk redness increased significantly in the order control < yellow < orange < purple. A similar trend was seen for yolk yellowness, but yellow and orange carrots reached the same level. Yolk colour and carotenoid contents correlated positively and significantly. In particular, purple carrot treatment increased the yolk content of lutein (>1.5-fold) and beta-carotene (>100-fold) compared with the control. Supplementing the feed of egg-laying hens with coloured carrots efficiently increased yolk colour parameters and carotenoid contents, which gives opportunities for improved nutritional value of eggs from forage material-supplemented hens.

Patterns of maternal yolk hormones in eastern screech owl eggs (Megascops asio)

USGS Publications Warehouse

Hahn, D. Caldwell

2011-01-01

Owl clutches typically hatch asynchronously, and brood size hierarchies develop. In this study, we describe intra-clutch variation of testosterone, androstenedione, estradiol, and corticosterone in Eastern screech owl egg yolks. In order to assess whether these hormones may have originated in the follicle, we also characterize variation of testosterone, androstenedione, and corticosterone within the exterior, intermediate, and interior regions of the yolk. Concentrations of testosterone and androstenedione were distributed relatively evenly across egg lay order with the exception of first-laid eggs that had significantly lower concentrations of both androgens than eggs later in the laying sequence. Corticosterone and estradiol did not vary with laying order. Our results suggest that when food is abundant, yolk hormones are deposited in patterns that minimize sibling differences except to reduce dominance by the first-hatching chick. Testosterone and androstenedione concentrations varied throughout the yolk, while corticosterone was evenly distributed throughout the yolk. This supports a follicular origin for both yolk androgens, and an adrenal origin for yolk corticosterone.

The effects of housing systems for laying hens on egg safety and quality

USDA-ARS?s Scientific Manuscript database

Transitions in laying hen management and housing systems have constantly occurred throughout the history of commercial egg production. Around the world, there has been a rapid shift in hen housing requirements since the turn of the current century. In most cases, the changes in hen housing require...

A new method for distinguishing colony social forms of the fire ant Solenopsis invicta

USDA-ARS?s Scientific Manuscript database

Two distinct forms of colony social organization occur in the fire ant Solenopsis invicta: Colonies of the monogyne social form are headed by a single egg-laying queen, whereas those of the polygyne social form contain multiple egg-laying queens. This major difference in social organization is ass...

Colonization of internal organs by Salmonella serovars Heidelberg and Typhimurium in experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Contaminated eggs produced by infected commercial laying flocks are often implicated as sources of human infections with Salmonella Enteritidis, but Salmonella serovars Heidelberg and Typhimurium have also been significantly associated with egg-transmitted illness. Contamination of the edible conten...

Studies on some feed additives and materials giving partial protection against the suppressive effect of ochratoxin A on egg production of laying hens.

PubMed

Stoev, Stoycho D

2010-06-01

The protective effects of various feed supplements against the harmful effect of ochratoxin A on egg production and sexual maturation of two-weeks old Plymouth Rock female chicks designed for laying hens were studied. A significant protective effect of the feed additives or materials: water extract of artichoke (WEA), sesame seed (SS), Roxazyme-G (RG) and l-beta phenylalanine (PHE) against the suppressive effect of ochratoxin A (OTA) on egg production of laying hens was found. A similar protection was also seen on the toxic effect of OTA on various internal organs of the same hens. A significant protection was found against the decrease of the weight or the quantity of eggs as well as against the delay of the beginning of the laying period of chicks, both of which were provoked by ochratoxin A. These protective effects were strongest in chicks treated with SS or WEA, but were slightest in chicks treated with l-beta PHE. Copyright 2009 Elsevier Ltd. All rights reserved.

Arsenic in Eggs and Excreta of Laying Hens in Bangladesh: A Preliminary Study

PubMed Central

Awal, M. A.; Majumder, Shankar; Mostofa, Mahbub; Khair, Abul; Islam, M. Z.; Rao, D. Ramkishan

2012-01-01

The aim of this study was to detect arsenic concentrations in feed, well-water for drinking, eggs, and excreta of laying hens in arsenic-prone areas of Bangladesh and to assess the effect of arsenic-containing feed and well-water on the accumulation of arsenic in eggs and excreta of the same subject. One egg from each laying hen (n=248) and its excreta, feed, and well-water for drinking were collected. Total arsenic concentrations were determined by atomic absorption spectrophotometer, coupled with hydride generator. Effects of arsenic-containing feed and drinking-water on the accumulation of arsenic in eggs and excreta were analyzed by multivariate regression model, using Stata software. Mean arsenic concentrations in drinking-water, feed (dry weight [DW]), egg (wet weight [WW]), and excreta (DW) of hens were 77.3, 176.6, 19.2, and 1,439.9 ppb respectively. Significant (p<0.01) positive correlations were found between the arsenic contents in eggs and drinking-water (r=0.602), drinking-water and excreta (r=0.716), feed and excreta (r=0.402) as well as between the arsenic content in eggs and the age of the layer (r=0.243). On an average, 55% and 82% of the total variation in arsenic contents of eggs and excreta respectively could be attributed to the variation in the geographic area, age, feed type, and arsenic contents of drinking-water and feed. For each week's increase in age of hens, arsenic content in eggs increased by 0.94%. For every 1% elevation of arsenic in drinking-water, arsenic in eggs and excreta increased by 0.41% and 0.44% respectively whereas for a 1% rise of arsenic in feed, arsenic in eggs and excreta increased by 0.40% and 0.52% respectively. These results provide evidence that, although high arsenic level prevails in well-water for drinking in Bangladesh, the arsenic shows low biological transmission capability from body to eggs and, thus, the value was below the maximum tolerable limit for humans. However, arsenic in drinking-water and/or feed makes a significant contribution to the arsenic accumulations in eggs and excreta of laying hens. PMID:23304904

Arsenic in eggs and excreta of laying hens in Bangladesh: a preliminary study.

PubMed

Ghosh, Amalendu; Awal, M A; Majumder, Shankar; Mostofa, Mahbub; Khair, Abul; Islam, M Z; Rao, D Ramkishan

2012-12-01

The aim of this study was to detect arsenic concentrations in feed, well-water for drinking, eggs, and excreta of laying hens in arsenic-prone areas of Bangladesh and to assess the effect of arsenic-containing feed and well-water on the accumulation of arsenic in eggs and excreta of the same subject. One egg from each laying hen (n = 248) and its excreta, feed, and well-water for drinking were collected. Total arsenic concentrations were determined by atomic absorption spectrophotometer, coupled with hydride generator. Effects of arsenic-containing feed and drinking-water on the accumulation of arsenic in eggs and excreta were analyzed by multivariate regression model, using Stata software. Mean arsenic concentrations in drinking-water, feed (dry weight [DW]), egg (wet weight [WW]), and excreta (DW) of hens were 77.3, 176.6, 19.2, and 1,439.9 ppb respectively. Significant (p < 0.01) positive correlations were found between the arsenic contents in eggs and drinking-water (r = 0.602), drinking-water and excreta (r = 0.716), feed and excreta (r = 0.402) as well as between the arsenic content in eggs and the age of the layer (r = 0.243). On an average, 55% and 82% of the total variation in arsenic contents of eggs and excreta respectively could be attributed to the variation in the geographic area, age, feed type, and arsenic contents of drinking-water and feed. For each week's increase in age of hens, arsenic content in eggs increased by 0.94%. For every 1% elevation of arsenic in drinking-water, arsenic in eggs and excreta increased by 0.41% and 0.44% respectively whereas for a 1% rise of arsenic in feed, arsenic in eggs and excreta increased by 0.40% and 0.52% respectively. These results provide evidence that, although high arsenic level prevails in well-water for drinking in Bangladesh, the arsenic shows low biological transmission capability from body to eggs and, thus, the value was below the maximum tolerable limit for humans. However, arsenic in drinking-water and/or feed makes a significant contribution to the arsenic accumulations in eggs and excreta of laying hens.

Commercially laid eggs vs. discarded hatching eggs: contamination by Salmonella spp.

PubMed

Kottwitz, Luciana B M; Leão, Joice Aparecida; Back, Alberto; Rodrigues, Dalia dos P; Magnani, Marciane; de Oliveira, Tereza C R M

2013-01-01

Salmonella enterica is frequently associated with outbreaks of human salmonellosis, and products of avian origin, such as eggs and chicken meat, are the main vehicles of its transmission. The present study describes the occurrence of different serovars of Salmonella enterica and phagotypes of S. enterica serovar Enteritidis in eggs destined for human consumption. Four thousand eggs obtained from commercial egg laying farms and one thousand discarded hatching eggs from broiler farms, which were acquired at farmers' markets and informal shops, were analyzed. Salmonella spp. was isolated from 52.0% of the discarded hatching eggs, in which the predominant serovar was Enteritidis (84.6%), and the predominant Salmonella Enteritidis phagotype (PT) was PT7 (26.9%). Salmonella spp. was not isolated from eggs obtained from commercial egg laying farms. The antimicrobial resistance profile showed that 23.1% (n = 6) of the SE strains were resistant to nalidixic acid. The results suggest that the consumption of discarded hatching eggs represents an important source of Salmonella transmission to humans.

Laying date, incubation and egg breakage as determinants of bacterial load on bird eggshells: experimental evidence.

PubMed

Soler, Juan José; Ruiz-Rodríguez, Magdalena; Martín-Vivaldi, Manuel; Peralta-Sánchez, Juan Manuel; Ruiz-Castellano, Cristina; Tomás, Gustavo

2015-09-01

Exploring factors guiding interactions of bacterial communities with animals has become of primary importance for ecologists and evolutionary biologists during the last years because of their likely central role in the evolution of animal life history traits. We explored the association between laying date and eggshell bacterial load (mesophilic bacteria, Enterobacteriaceae, Staphylococci, and Enterococci) in natural and artificial magpie (Pica pica) nests containing fresh commercial quail (Coturnix coturnix) eggs. We manipulated hygiene conditions by spilling egg contents on magpie and artificial nests and explored experimental effects during the breeding season. Egg breakage is a common outcome of brood parasitism by great spotted cuckoos (Clamator glandarius) on the nests of magpie, one of its main hosts. We found that the treatment increased eggshell bacterial load in artificial nests, but not in magpie nests with incubating females, which suggests that parental activity prevents the proliferation of bacteria on the eggshells in relation to egg breakage. Moreover, laying date was positively related to eggshell bacterial load in active magpie nests, but negatively in artificial nests. The results suggest that variation in parental characteristics of magpies rather than climatic variation during the breeding season explained the detected positive association. Because the eggshell bacterial load is a proxy of hatching success, the detected positive association between eggshell bacterial loads and laying date in natural, but not in artificial nests, suggests that the generalized negative association between laying date and avian breeding success can be, at least partially, explained by differential bacterial effects.

An Optimal Dietary Zinc Level of Brown-Egg Laying Hens Fed a Corn-Soybean Meal Diet.

PubMed

Qin, Shizhen; Lu, Lin; Zhang, Xichun; Liao, Xiudong; Zhang, Liyang; Guo, Yanli; Luo, Xugang

2017-06-01

An experiment was conducted to estimate the optimal dietary zinc (Zn) level of brown-egg laying hens fed a corn-soybean meal diet from 20 to 40 weeks of age. A total of 120 20-week-old Beijing Red commercial laying hens were randomly allotted by bodyweight to one of five treatments with six replicates of four birds each in a completely randomized design, and fed a Zn-unsupplemented corn-soybean meal basal diet containing 27.95 mg Zn/kg by analysis and the basal diets supplemented with 30, 60, 90, or 120 mg Zn/kg as Zn sulfate (reagent grade ZnSO 4 ·7H 2 O) for a duration of 20 weeks. Laying performance, egg quality, tissue Zn concentrations, and activities of serum alkaline phosphatase (AKP), and liver copper-Zn superoxide dismutase (CuZnSOD) were measured. Regression analyses were performed to estimate an optimal dietary Zn level whenever a significant quadratic response (P < 0.05) was observed. Tibia Zn concentration (P = 0.002) and serum AKP activity (P = 0.010) showed significant quadratic responses to dietary supplemental Zn levels. The estimates of dietary Zn requirements for brown-egg laying hens from 20 to 40 weeks of age were 71.95 and 64.63 mg/kg for tibia Zn concentration and serum AKP activity, respectively. The results from this study indicate that the tibia Zn might be a more suitable and reliable parameter for Zn requirement estimation, and the optimal dietary Zn level would be about 72 mg/kg for brown-egg laying hens fed a corn-soybean meal diet from 20 to 40 weeks of age.

Nonmotorized recreation and motorized recreation in shrub-steppe habitats affects behavior and reproduction of golden eagles (Aquila chrysaetos).

PubMed

Spaul, Robert J; Heath, Julie A

2016-11-01

Different forms of outdoor recreation have different spatiotemporal activity patterns that may have interactive or cumulative effects on wildlife through human disturbance, physical habitat change, or both. In western North America, shrub-steppe habitats near urban areas are popular sites for motorized recreation and nonmotorized recreation and can provide important habitat for protected species, including golden eagles. Our objective was to determine whether recreation use (i.e., number of recreationists) or recreation features (e.g., trails or campsites) predicted golden eagle territory occupancy, egg-laying, or the probability a breeding attempt resulted in ≥1 offspring (nest survival). We monitored egg-laying, hatching and fledging success, eagle behavior, and recreation activity within 23 eagle territories near Boise, Idaho, USA. Territories with more off-road vehicle (ORV) use were less likely to be occupied than territories with less ORV use (β = -1.6, 85% CI: -2.8 to -0.8). At occupied territories, early season pedestrian use (β = -1.6, 85% CI: -3.8 to -0.2) and other nonmotorized use (β = -3.6, 85% CI: -10.7 to -0.3) reduced the probability of egg-laying. At territories where eagles laid eggs, short, interval-specific peaks in ORV use were associated with decreased nest survival (β = -0.5, 85% CI: -0.8 to -0.2). Pedestrians, who often arrived near eagle nests via motorized vehicles, were associated with reduced nest attendance (β = -11.9, 85% CI: -19.2 to -4.5), an important predictor of nest survival. Multiple forms of recreation may have cumulative effects on local populations by reducing occupancy at otherwise suitable territories, decreasing breeding attempts, and causing nesting failure. Seasonal no-stopping zones for motorized vehicles may be an alternative to trail closures for managing disturbance. This study demonstrates the importance of considering human disturbance across different parts of the annual cycle, particularly where multiple forms of recreation have varying spatiotemporal use patterns that create human-wildlife interactions.

COMPARISON OF TWO 4.7-MILLIGRAM TO ONE 9.4-MILLIGRAM DESLORELIN ACETATE IMPLANTS ON EGG PRODUCTION AND PLASMA PROGESTERONE CONCENTRATIONS IN JAPANESE QUAIL (COTURNIX COTURNIX JAPONICA).

PubMed

Petritz, Olivia A; Guzman, David Sanchez-Migallon; Hawkins, Michelle G; Kass, Philip H; Conley, Alan J; Paul-Murphy, Joanne

2015-12-01

Reproductive disease in captive avian species is common, and medical management is often chosen over surgical removal of the reproductive tract. In a previous study with Japanese quail, a single 4.7-mg deslorelin acetate implant reversibly decreased egg production in 6 out 10 birds for 70 days. The objective of the current study was to evaluate the effects of two 4.7-mg deslorelin acetate implants versus one 9.4-mg implant on egg production and plasma progesterone concentrations in Japanese quail ( Coturnix coturnix japonica). Following a 10-day period of consistent egg laying, 30 adult female Japanese quail were anesthetized and received two 4.7-mg deslorelin implants (n = 10), one 9.4-mg deslorelin implant (n = 10), or a single, identical placebo implant (n = 10) s.c. between the scapulae. Egg production was monitored daily, and plasma progesterone concentrations were measured on days 0, 14, 29, 120, 148, and 182 via enzyme-linked immunoassay. All birds were weighed periodically and euthanized at day 182, after which their reproductive tracts were evaluated at gross necropsy. Seven out of 10 birds treated with two 4.7-mg implants ceased egg laying 1 wk after implantation and remained nonovulatory for approximately 100 days. Cessation of egg laying for the 9.4-mg treatment group occurred in 7 out of 10 birds; onset was variable (weeks 5-12) and continued for the remainder of the study period. Plasma progesterone concentrations for deslorelin treatment groups were not significantly different compared to the placebo group at any time point. In conclusion, the two 4.7-mg and the one 9.4-mg implant treatments ceased egg laying in a similar number of birds, but the 9.4-mg implant had a slower onset of action and the effects on egg laying were inconsistent throughout the study period. Further studies evaluating use of deslorelin acetate in other avian species are needed.

Effects of faba beans with different concentrations of vicine and convicine on egg production, egg quality and red blood cells in laying hens.

PubMed

Lessire, M; Gallo, V; Prato, M; Akide-Ndunge, O; Mandili, G; Marget, P; Arese, P; Duc, G

2017-08-01

The faba bean (Vicia faba L.) is a potential source of proteins for poultry, mainly for laying hens whose protein requirements are lower than those of other birds such as growing broilers and turkeys. However, this feedstuff contains anti-nutritional factors, that is, vicine (V) and convicine (C) that are already known to reduce laying hen performance. The aim of the experiment reported here was to evaluate the effects of a wide range of dietary V and C concentrations in laying hens. Two trials were performed with laying hens fed diets including 20% or 25% of faba bean genotypes highly contrasting in V+C content. In Trial 1, faba beans from two tannin-containing cultivars, but with high or low V+C content were dehulled in order to eliminate the tannin effect. In addition to the contrasting levels of V+C in the two cultivars, two intermediate levels of V+C were obtained by mixing the two cultivars (70/30 and 30/70). In Trial 2, two isogenic zero-tannin faba bean genotypes with high or low V+C content were used. In both trials, a classical corn-soybean diet was also offered to control hens. Each experimental diet was given to 48 laying hens for 140 (Trial 1) or 89 (Trial 2) days. Laying performance and egg quality were measured. The redox sensitivity of red blood cells (RBCs) was assessed by measuring hemolysis and reduced glutathione (GSH) concentration in these cells. Egg weight was significantly reduced by the diets containing the highest concentrations of V+C (P<0.0001) in Trial 1 and slightly reduced (P<0.10) in Trial 2, but only weak linear relationships between egg weight and dietary V+C concentration were established. No negative effect of V+C level was observed for egg quality parameters. In contrast, certain parameters (i.e. Haugh units, yolk color) were improved by feeding low V+C diets (P<0.05). Hemolysis of RBCs was higher in hens fed high V+C diets. A decrease in GSH concentration in RBCs of hens fed the highest levels of V+C was observed. Faba bean genotypes with low concentrations of V+C can therefore be used in laying hen diets up to 25% without any detrimental effects on performance levels or egg characteristics, without any risk of hemolysis of RBCs.

Exterior egg quality as affected by enrichment resources layout in furnished laying-hen cages.

PubMed

Li, Xiang; Chen, Donghua; Meng, Fanyu; Su, Yingying; Wang, Lisha; Zhang, Runxiang; Li, Jianhong; Bao, Jun

2017-10-01

This study aimed to investigate the effects of enrichment resources (a perch, dustbath, and nest) layout in furnished laying-hen cages (FC) on exterior quality of eggs. One hundred and sixty-eight (168) Hy-Line Brown laying hens at 16 weeks of age were randomly distributed to four treatments: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III). Each treatment had 4 replicates or cages with 6 hens for SFC (24 birds for each SFC) and 12 hen/cage for MFC-I, -II, and -III (48 birds for each MFC-I, -II and -III). Following a 2-week acclimation, data collection started at 18 weeks of age and continued till 52 weeks of age. Dirtiness of egg surface or cracked shell as indicators of the exterior egg quality were recorded each week. The results showed that the proportion of cracked or dirty eggs was significantly affected by the FC type (p<0.01) in that the highest proportion of cracked or dirty eggs was found in MFC-I and the lowest proportion of dirty eggs in SFC. The results of this showed that furnished cage types affected both dirty eggs and cracked eggs (p<0.01). The results also indicated that not nest but dustbath lead to more dirty eggs. Only MFC-I had higher dirty eggs at nest than other FC (p< 0.01). The results of dirty eggs in MFC-I and MFC-II compared with SFC and MFC-III seemed suggest that a low position of dustbath led to more dirty eggs. SFC design affected exterior egg quality and the low position of dustbath in FC resulted in higher proportion of dirty eggs.

Effects of egg order on organic and inorganic element concentrations and egg characteristics in tree swallows, tachycineta bicolor

USGS Publications Warehouse

Custer, Christine M.; Gray, B.R.; Custer, T.W.

2010-01-01

The laying order of tree swallow eggs was identified from the Housatonic River, Berkshire County, Massachusetts, USA, and eggs were chemically analyzed individually to document possible effects of laying order on organic contaminant and inorganic element concentrations. Effects of laying order on other parameters such as egg weight, size, and lipid and moisture content also were assessed. Some effects of egg order on total polychlorinated biphenyls (PCBs) were detected, but the effect was not uniform across individual females or between years. In 2004, clutches with higher total PCBs tended to have concentrations decline across egg order, whereas clutches with lower concentrations of PCBs tended to increase across egg order. In contrast, in 2005, there was a tendency for concentrations to increase across egg order. Polychlorinated biphenyl concentrations were highly variable within and among clutches in both years. The directionality of egg order associations (i.e., slopes) for trace elements was element dependent, was positive for Mn and Zn, was negative for B, and had no slope for Cr. Whole egg weight increased across egg order. Percentage lipid was variable within a clutch, with no pattern common across all females. Percentage lipid was also correlated with organic contaminant concentration. In highly contaminated environments, higher lipid content could have the unanticipated corollary of having higher concentrations of lipophilic contaminants such as PCBs. To reduce the effect of high variation within a clutch when assessing contamination exposure, it is recommended that two eggs per clutch be collected and pooled for chemical analysis. We further recommend that, as long as the two eggs are randomly collected, the additional effort needed to identify and collect specific eggs is not warranted. ?? 2009 SETAC.

Partial albumen removal early during embryonic development of layer-type chickens has negative consequences on laying performance in adult life.

PubMed

Willems, E; Wang, Y; Willemsen, H; Lesuisse, J; Franssens, L; Guo, X; Koppenol, A; Buyse, J; Decuypere, E; Everaert, N

2013-07-01

To examine the importance of albumen as a protein source during embryonic development on the posthatch performance of laying hens, 3 mL of the albumen was removed. At hatch, no difference in BW could be observed. Chicks from the albumen-deprived group had a lower residual yolk weight due to higher yolk utilization. During the rearing phase (hatch to 17 wk of age), the BW of the albumen-deprived pullets was lower compared with the control and sham pullets. The feed intake of the albumen-deprived pullets was also lower than the control pullets. However, during the laying phase (18 to 55 wk of age) these hens exceeded the control and sham hens in BW, although this was not accompanied by a higher feed intake. The albumen-deprived hens exhibited a lower egg production capacity as demonstrated by the reduced egg weight, laying rate, and egg mass and increased number of second grade eggs. In addition, the eggs laid by the albumen-deprived hens had a higher proportional yolk and lower proportional albumen weight. In conclusion, prenatal protein deprivation by albumen removal caused a long-lasting programming effect, possibly by differences in energy allocation, in favor of growth and maintenance and impairing reproductive performance.

Effects of dietary supplementation with Gynura procumbens (Merr.) on egg yolk cholesterol, excreta microflora and laying hen performance.

PubMed

Lokhande, A; Ingale, S L; Lee, S H; Sen, S; Khong, C; Chae, B J; Kwon, I K

2014-01-01

Abstract 1. The present study investigated the effects of dietary supplementation with Gynura procumbens on egg yolk and serum cholesterol and triglycerides, excreta microflora, laying performance and egg quality. 2. A total of 160 Hy-Line Brown layers (45 weeks old) were randomly assigned into 4 treatments on the basis of laying performance. Each treatment had 4 replicates with 10 birds each. 3. Dietary treatments were basal diet supplemented with 0 (control), 2.5, 5.0 and 7.5 g/kg diet G. procumbens during 56-d feeding period. 4. Serum (d 21, 42 and 56) and egg yolk (d 28, 42 and 56) cholesterol and triglycerides concentrations were linearly reduced with increasing dietary concentrations of G. procumbens. 5. Increasing dietary concentrations of G. procumbens linearly reduced the excreta total anaerobic bacteria (d 28), Clostridium sp. and Escherichia coli (d 28 and 56) populations. 6. Overall egg production and egg mass were linearly increased, and overall feed efficiency was linearly improved with increase in dietary G. procumbens. 7. Dietary increasing concentrations of G. procumbens linearly improved egg yolk colour (d 28 and 56) and breaking strength of eggs (d 56). 8. The results obtained in the present experiment indicate that dietary supplementation with G. procumbens could reduce the egg yolk cholesterol, suppresses harmful excreta microflora and improves layers performance.

Opinion of Belgian Egg Farmers on Hen Welfare and Its Relationship with Housing Type

PubMed Central

Stadig, Lisanne M.; Ampe, Bart A.; Van Gansbeke, Suzy; Van den Bogaert, Tom; D’Haenens, Evelien; Heerkens, Jasper L.T.; Tuyttens, Frank A.M.

2015-01-01

Simple Summary Until 2012, laying hens in the EU were often housed in conventional cages that offered limited space and few opportunities to perform highly motivated behaviors. Conventional cages are now banned in the EU in order to improve animal welfare. In this study, egg farmers were surveyed (winter 2013–2014) to assess whether they perceived any changes in animal welfare since changing housing systems, what role hen welfare played in choosing a new housing system, and which aspects of hen welfare they find most important. The data show that the answers differ depending on which housing system the farmers currently use and whether they had used conventional cages in the past. Abstract As of 2012, the EU has banned the use of conventional cages (CC) for laying hens, causing a shift in housing systems. This study’s aim was to gain insight into farmers’ opinions on hen health and welfare in their current housing systems. A survey was sent to 218 Belgian egg farmers, of which 127 (58.3%) responded, with 84 still active as egg farmer. Hen welfare tended to be less important in choosing the housing system for farmers with cage than with non-cage systems. Respondents currently using cage systems were more satisfied with hen health than respondents with non-cage systems. Reported mortality increased with farm size and was higher in furnished cages than in floor housing. Feather pecking, cannibalism, smothering and mortality were perceived to be higher in current housing systems than in CC, but only by respondents who shifted to non-cage systems from previously having had CC. Health- and production-related parameters were scored to be more important for hen welfare as compared to behavior-related parameters. Those without CC in the past rated factors relating to natural behavior to be more important for welfare than those with CC. This difference in opinion based on farmer backgrounds should be taken into account in future research. PMID:26703742

Effect of nanosilicon dioxide on growth performance, egg quality, liver histopathology and concentration of calcium, phosphorus and silicon in egg, liver and bone in laying quails

NASA Astrophysics Data System (ADS)

Faryadi, Samira; Sheikhahmadi, Ardashir

2017-11-01

This experiment was conducted to evaluate the effects of different levels of nanosilicon dioxide (nSiO2) on performance, egg quality, liver histopathology and concentration of calcium (Ca), phosphorus and silicon (Si) in egg, liver and bone in laying quails. The experiment was administered using 60 laying quails at 16-26 weeks of age with five treatments [0 (control), 500, 1000, 2000 and 4000 mg nSiO2 per kg of diet] and four replicates in a completely randomized design. During the experiment, the amount of feed intake was recorded weekly and performance parameters were measured. During the last 3 days of the experiment, all of the eggs in each replicate were collected and egg quality parameters were measured. At the end of 26 weeks of age, the birds were sacrificed and blood samples were collected. Liver samples from each treatment were fixed in 10% buffered formalin for histopathological assessment. The right thigh bone and a portion of liver were inserted in plastic bags and stored at - 20. The results showed that nSiO2 supplementation significantly affected egg weight and egg mass ( P < 0.05). Also, dietary nSiO2 supplementation decreased the yolk weight and increased the shell weight ( P < 0.05). Moreover, nSiO2 increased bone ash content, Ca and Si concentration in the bone ( P < 0.05). The liver enzymes in plasma and the liver tissue histopathology were not significantly affected ( P > 0.05) by dietary treatments. In conclusion, the results indicated that dietary supplementation of nSiO2 could improve bone density and performance without any adverse effect on the health of laying quails.

Long-term reproductive and behavioral toxicity of anthracene to fish in the presence of solar ultraviolet radiation

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

Hall, A.T.; Oris, J.T.

1994-12-31

The long-term, low-level effects of anthracene in the presence of solar ultraviolet radiation (SUVR) were examined in the fathead minnow (Pimephales promelas). Adult fish exposed to anthracene exhibited reduced egg laying capacity, with altered oocyte maturation as a potential mechanism of action. Eggs and larvae maternally exposed to anthracene exhibited reduced hatching success and severe developmental abnormalities when incubated under SUVR. The combination of reduced egg output and developmental effects resulted in an inhibition in reproductive capacity in the range of 70--100%. Maternal transfer of anthracene to eggs was efficient; the BCF was 717 for maternally exposed eggs. However, anthracenemore » deputation from eggs after oviposition with only maternal PAH exposure was rapid; anthracene half-life from eggs equaled 1.3 days. Exposure to anthracene under SUVR altered locomotor activity patterns in fathead minnows by inducing hyperactivity or hypoactivity during the light or dark phases of the photoperiod, respectively. Altered activity patterns indicated potential effects of anthracene on the nervous system and/or pineal gland. These alterations disrupted normal activity patterns and reproductive behaviors, and thus have major implications on a fish`s ability to survive and reproduce. Anthracene, a model phototoxic PAH, has many potential sites of toxic action, and any organism exposed to such contaminants will be an considerable SUVR-enhanced risk in the environment.« less

Frequency and persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Human infections with Salmonella Enteritidis are often attributed to the consumption of contaminated eggs, so the prevalence of this pathogen in egg-laying poultry is an important public health risk factor. Numerous and complex environmental influences on Salmonella persistence and transmission are ...

In vivo and in vitro evaluation of tissue colonization and survival capacity of Salmonella Oranienburg in laying hens

USDA-ARS?s Scientific Manuscript database

Salmonella Oranienburg (SO) was linked to a human salmonellosis outbreak in the Midwest in 2015 and 2016 from consumption of eggs. However, unlike Salmonella Enteritidis (SE), little is known regarding the potential of SO to colonize in laying hens and contaminate eggs. We used in vivo and in vitr...

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

Naïve hosts of avian brood parasites accept foreign eggs, whereas older hosts fine-tune foreign egg discrimination during laying

PubMed Central

2014-01-01

Background Many potential hosts of social parasites recognize and reject foreign intruders, and reduce or altogether escape the negative impacts of parasitism. The ontogenetic basis of whether and how avian hosts recognize their own and the brood parasitic eggs remains unclear. By repeatedly parasitizing the same hosts with a consistent parasitic egg type, and contrasting the responses of naïve and older breeders, we studied ontogenetic plasticity in the rejection of foreign eggs by the great reed warbler (Acrocephalus arundinaceus), a host species of the common cuckoo (Cuculus canorus). Results In response to experimental parasitism before the onset of laying, first time breeding hosts showed almost no egg ejection, compared to higher rates of ejection in older breeders. Young birds continued to accept foreign eggs when they were subjected to repeated parasitism, whereas older birds showed even higher ejection rates later in the same laying cycle. Conclusions Our results are consistent with the hypotheses that (i) naïve hosts need to see and learn the appearance of their own eggs to discriminate and reject foreign eggs, whereas (ii) experienced breeders possess a recognition template of their own eggs and reject parasitic eggs even without having to see their own eggs. However, we cannot exclude the possibility that other external cues and internal processes, accumulated simply with increasing age, may also modify age-specific patterns in egg rejection (e.g. more sightings of the cuckoo by older breeders). Future research should specifically track the potential role of learning in responses of individual hosts between first and subsequent breeding attempts by testing whether imprinting on a parasitized clutch reduces the rates of rejecting foreign eggs in subsequent parasitized clutches. PMID:25024736

Identification of Promising Mutants Associated with Egg Production Traits Revealed by Genome-Wide Association Study.

PubMed

Yuan, Jingwei; Sun, Congjiao; Dou, Taocun; Yi, Guoqiang; Qu, LuJiang; Qu, Liang; Wang, Kehua; Yang, Ning

2015-01-01

Egg number (EN), egg laying rate (LR) and age at first egg (AFE) are important production traits related to egg production in poultry industry. To better understand the knowledge of genetic architecture of dynamic EN during the whole laying cycle and provide the precise positions of associated variants for EN, LR and AFE, laying records from 21 to 72 weeks of age were collected individually for 1,534 F2 hens produced by reciprocal crosses between White Leghorn and Dongxiang Blue-shelled chicken, and their genotypes were assayed by chicken 600 K Affymetrix high density genotyping arrays. Subsequently, pedigree and SNP-based genetic parameters were estimated and a genome-wide association study (GWAS) was conducted on EN, LR and AFE. The heritability estimates were similar between pedigree and SNP-based estimates varying from 0.17 to 0.36. In the GWA analysis, we identified nine genome-wide significant loci associated with EN of the laying periods from 21 to 26 weeks, 27 to 36 weeks and 37 to 72 weeks. Analysis of GTF2A1 and CLSPN suggested that they influenced the function of ovary and uterus, and may be considered as relevant candidates. The identified SNP rs314448799 for accumulative EN from 21 to 40 weeks on chromosome 5 created phenotypic differences of 6.86 eggs between two homozygous genotypes, which could be potentially applied to the molecular breeding for EN selection. Moreover, our finding showed that LR was a moderate polygenic trait. The suggestive significant region on chromosome 16 for AFE suggested the relationship between sex maturity and immune in the current population. The present study comprehensively evaluates the role of genetic variants in the development of egg laying. The findings will be helpful to investigation of causative genes function and future marker-assisted selection and genomic selection in chickens.

Effects of adding aqueous extract of Tribulus terrestris to diet on productive performance, egg quality characteristics, and blood biochemical parameters of laying hens reared under low ambient temperature (6.8 ± 3 °C)

NASA Astrophysics Data System (ADS)

Akbari, Mohsen; Torki, Mehran

2016-06-01

A study was conducted using 144 laying hens to evaluate the effects of adding aqueous extract of Tribulus terrestris to diets on productive performance, egg quality traits, and some blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C). The birds were randomly assigned to each of four dietary treatments (C, T1, T2, and T3) with six replicate cages of six birds. Diet inclusion of aqueous extract of T. terrestris at the rate of 10, 20, and 30 ml/Lit offered to groups T1, T2, and T3, respectively, while group C served as the control diet with no addition. Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 42-day trial period. The EP and EM increased, whereas FCR decreased ( P < 0.001) in the hens fed the extract-included diet as compared to those fed the basal diet. The serum content of cholesterol decreased and the thickness of egg shell increased in the hens fed the T2 and T3 diet compared to those fed the basal diet. Overall from the results of the present experiment, it can be concluded that diet supplementation with aqueous extract of T. terrestris has beneficial effects on productive performance of laying hens reared under cold stress condition.

Decreased egg production in laying hens associated with infection with genotype 3 avian hepatitis E virus strain from China.

PubMed

Zhao, Qin; Liu, Baoyuan; Sun, Yani; Du, Taofeng; Chen, Yiyang; Wang, Xinjie; Li, Huixia; Nan, Yuchen; Zhang, Gaiping; Zhou, En-Min

2017-05-01

To determine the relationship between decreased egg production and avian HEV infection, thirty healthy 23-week-old Hy-Line Variety Brown layer hens were randomly divided into 3 groups with 10 hens per group. Next, a genotype 3 avian HEV strain from China was used to inoculate laying hens via oronasal or intravenous routes using a 50% chicken infectious dose of 500. All hens were necropsied at 14 weeks postinoculation (wpi). Fecal virus shedding, viremia, seroconversion, serum alanine aminotransferase (ALT) increases and liver lesions showed that after intravenous (i.v.) and oronasal inoculation, the laying hens were successfully infected. Compared with the uninoculated group, the i.v. and oronasally inoculated groups exhibited egg production decreases at 1wpi and 2wpi, reaching peak production at 3wpi and 8wpi, respectively. In both groups, decreased production was evident for 12 weeks and overall decreases ranged from 10% to 30%. In addition, in the 7 field layer farms exhibiting decreased egg production, vaccination regimens had been completed against Newcastle disease, infectious bronchitis, avian influenza H9N2 and H5N1 and egg drop syndrome virus. However, circulating avian HEV was confirmed on these farms using tests to detect avian HEV IgG antibodies and RNA. Therefore, the experimental and field data indicate that avian HEV infection acting alone could account for observed decreases in egg production in laying hens. Copyright © 2017 Elsevier B.V. All rights reserved.

Nest destruction elicits indiscriminate con- versus heterospecific brood parasitism in a captive bird.

PubMed

Shaw, Rachael C; Feeney, William E; Hauber, Mark E

2014-12-01

Following nest destruction, the laying of physiologically committed eggs (eggs that are ovulated, yolked, and making their way through the oviduct) in the nests of other birds is considered a viable pathway for the evolution of obligate interspecific brood parasitism. While intraspecific brood parasitism in response to nest predation has been experimentally demonstrated, this pathway has yet to be evaluated in an interspecific context. We studied patterns of egg laying following experimental nest destruction in captive zebra finches, Taeniopygia guttata, a frequent intraspecific brood parasite. We found that zebra finches laid physiologically committed eggs indiscriminately between nests containing conspecific eggs and nests containing heterospecific eggs (of Bengalese finches, Lonchura striata vars. domestica), despite the con- and heterospecific eggs differing in both size and coloration. This is the first experimental evidence that nest destruction may provide a pathway for the evolution of interspecific brood parasitism in birds.

Timing of breeding and reproductive performance in murres and kittiwakes reflect mismatched seasonal prey dynamics

USGS Publications Warehouse

Shultz, M.T.; Piatt, John F.; Harding, A.M.A.; Kettle, Arthur B.; van Pelt, Thomas I.

2009-01-01

Seabirds are thought to time breeding to match the seasonal peak of food availability with peak chick energetic demands, but warming ocean temperatures have altered the timing of spring events, creating the potential for mismatches. The resilience of seabird populations to climate change depends on their ability to anticipate changes in the timing and magnitude of peak food availability and 'fine-tune' efforts to match ('Anticipation Hypothesis'). The degree that inter-annual variation in seabird timing of breeding and reproductive performance represents anticipated food availability versus energetic constraints ('Constraint Hypothesis') is poorly understood. We examined the relative merits of the Constraint and Anticipation Hypotheses by testing 2 predictions of the Constraint Hypothesis: (1) seabird timing of breeding is related to food availability prior to egg laying rather than the date of peak food availability, (2) initial reproductive output (e.g. laying success, clutch size) is related to pre-lay food availability rather than anticipated chick-rearing food availability. We analyzed breeding biology data of common murres Uria aalge and black-legged kittiwakes Rissa tridactyla and 2 proxies of the seasonal dynamics of their food availability (near-shore forage fish abundance and sea-surface temperature) at 2 colonies in Lower Cook Inlet, Alaska, USA, from 1996 to 1999. Our results support the Constraint Hypothesis: (1) for both species, egg laying was later in years with warmer sea-surface temperature and lower food availability prior to egg laying, but was not related to the date of peak food availability, (2) pre-egg laying food availability explained variation in kittiwake laying success and clutch size. Murre reproductive success was best explained by food availability during chick rearing. ?? 2009 Inter-Research.

Identification of novel QTL for sawfly resistance in wheat

Treesearch

J. D. Sherman; D. K. Weaver; M. L. Hofland; S. E. Sing; M. Buteler; S. P. Lanning; Y. Naruoka; F. Crutcher; N. K. Blake; J. M. Martin; P. F. Lamb; G. R. Carlson; L. E. Talbert

2010-01-01

The wheat stem sawfly (WSS) (Cephus cinctus Nort.) is an important pest of wheat (Triticum aestivum L. em. Thell.) in the Northern Great Plains. This paper reports the genetic analysis of antixenosis for egg-laying WSS females in recombinant inbred lines (RIL) of hard red spring wheat. Female WSS preferentially choose certain wheat genotypes for egg-laying, with the...

The effect of perch access during pullet rearing and egg laying on physiological measurements of stress in 71-week-old White Leghorns

USDA-ARS?s Scientific Manuscript database

Egg laying strains of chickens have a strong motivation to perch. Providing caged chickens with perches allows them to perform their natural perching instinct and also improves their musculoskeletal health due to exercise. Little is known about the effect of perch access by hens on physiological mea...

Dose-response feeding study of short chain chlorinated paraffins (SCCPs) in laying hens: effects on laying performance and tissue distribution, accumulation and elimination kinetics.

PubMed

Ueberschär, Karl-Heinz; Dänicke, Sven; Matthes, Siegfried

2007-02-01

Technical short chain chlorinated paraffins (C10-C13 with 60% chlorine) were fed to 93 laying hens from 24 to 32 weeks of age in increasing concentrations of up to 100 mg/kg feed. No significant influence on health, relative organ weights or performance (laying intensity, egg weight, feed consumption) was noted. The chlorinated paraffin content of the tissues was linearly related to the concentration of short chain paraffins of the feed. The highest concentrations were found in abdominal fat, egg yolk and fatty tissues. Breast muscle, egg albumen and bile fluid contained minimal or no residues. Less than 1% of the chlorinated paraffins ingested were incorporated into the body (without head, feet, gut and feathers), whereas about 1.5% were eliminated with the egg yolk and 30% were excreted with urine and faeces. A six-week kinetic depuration study revealed a biphasic elimination with half-lifes of 4-40 min (liver, kidneys, legs, fat, blood) for the initial rapid phase, and 15-30 days (blood, fat, liver, yolk, kidneys, legs) for the terminal slow phase.

Living with strangers: direct benefits favour non-kin cooperation in a communally nesting bird.

PubMed

Riehl, Christina

2011-06-07

The greater ani (Crotophaga major), a Neotropical cuckoo, exhibits an unusual breeding system in which several socially monogamous pairs lay eggs in a single nest and contribute care to the communal clutch. Cooperative nesting is costly-females compete for reproduction by ejecting each other's eggs-but the potential direct or indirect fitness benefits that might accrue to group members have not been identified. In this study, I used molecular genotyping to quantify patterns of genetic relatedness and individual reproductive success within social groups in a single colour-banded population. Microsatellite analysis of 122 individuals in 49 groups revealed that group members are not genetic relatives. Group size was strongly correlated with individual reproductive success: solitary pairs were extremely rare and never successful, and nests attended by two pairs were significantly more likely to be depredated than were nests attended by three pairs. Egg loss, a consequence of reproductive competition, was greater in large groups and disproportionately affected females that initiated laying. However, early-laying females compensated for egg losses by laying larger clutches, and female group members switched positions in the laying order across nesting attempts. The greater ani, therefore, appears to be one of the few species in which cooperative breeding among unrelated individuals is favoured by direct, shared benefits that outweigh the substantial costs of reproductive competition.

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

Reproductivity of Japanese quail fed mercuric chloride in the absence of vitamin D

USGS Publications Warehouse

Hill, E.F.; Soares, J.H.

1977-01-01

Mercuric chloride (HgCl2) was tested at 16 p.p.m. Hg for vitamin D sparing activity by presenting it dietarily in the presence and absence of 25-hydroxycholecalciferol (25-HCC) to Japanese quail (Coturnix c. japonica) for 25 days. No gross signs characteristic of mercury poisoning were observed, but some predictable effects of vitamin D deficiency on avian reproduction were manifested within 10 days. Rate of lay, egg shell thickness, and hatchability of fertile eggs decreased markedly for birds on vitamin D-deficient diets. Shell-less eggs were laid by these birds after 20 days and laying stopped entirely on the 23rd day. Laying resumed within 5 days after diets were refortified with 25-HCC. There was no detectable interaction between HgCl2 and vitamin D.

Single and combined effects of peppermint and thyme essential oils on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C)

NASA Astrophysics Data System (ADS)

Akbari, Mohsen; Torki, Mehran; Kaviani, Keyomars

2016-03-01

This study was conducted to evaluate the effects of adding peppermint essential oil (PEO), thyme essential oil (TEO), or their combination to diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-lite laying hens. Significant interactions between PEO and TEO on FCR, EP, and EM were observed ( P < 0.05). The EP and EM increased, whereas FCR decreased ( P < 0.05) in the hens fed the diets supplemented by the combined form of PEO and TEO compared to those fed the basal diet. Also, increased EW and FI were observed in the laying hens fed the diet added by PEO compared to the birds fed the basal diet. There were significant interactions between PEO and TEO on the serum level of cholesterol, shell thickness, and Hough unit of egg ( P < 0.05), so that serum content of cholesterol decreased, but egg shell thickness and Hough unit increased in the hens fed the diet supplemented by the combined form of PEO and TEO compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by combined form of PEO and TEO could have beneficial effects on performance parameters of hens reared under cold stress condition.

Reduction of aflatoxins by Korean soybean paste and its effect on cytotoxicity and reproductive toxicity--Part 3. Inhibitory effects of Korean soybean paste (doen-jang) on aflatoxin toxicity in laying hens and aflatoxin accumulation in their eggs.

PubMed

Kim, Jong-Gyu; Lee, Yong-Wook; Kim, Pan-Gyi; Roh, Woo-Sup; Shintani, Hideharu

2003-05-01

This study was conducted to determine the effects of Korean soybean paste (doen-jang [dwen-jahng]) (at concentrations of 0.5, 1, and 5%) on the toxicity of 500 ppb of aflatoxin in the diets of 60 laying hens (Isa Brown) divided into five groups and treated from week 15 to week 67. The aflatoxin-treated hens exhibited many deleterious effects, including reduced body weight; increased relative organ weights; decreased egg production; aflatoxin accumulation in eggs; decreased serum calcium, phosphorus, and alanino amonotransferase (ALT) levels; increased serum gammaglutamil transferase and lactic dehydrogenase levels; and, most significantly, severely altered cell foci and sinusoid dilatation in the liver, relative to control hens. The feeding of 1% soybean paste to hens reduced the adverse effects of aflatoxin on body weight, relative organ weights, egg production, and aflatoxin accumulation in eggs and improved serum calcium and ALT levels and the histopathological lesions of the liver. The feeding of 5% soybean paste to hens resulted in higher levels of the same types of improvements, especially with regard to the histopathological findings for the liver. On the basis of these results, it was suggested that a diet including 5% (and in some cases only 1%) Korean soybean paste protected laying hens and their eggs from the major deleterious effects of 500 microg of aflatoxin per kg of diet and from aflatoxin accumulation. These results indicate that dietary supplementation with Korean soybean paste reduces aflatoxin toxicity in laying hens that ultimately produce human foods such as eggs and poultry.

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.

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

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.

Tropism and infectivity of duck-derived egg drop syndrome virus in chickens.

PubMed

Kang, Min; Cha, Se-Yeoun; Jang, Hyung-Kwan

2017-01-01

Egg drop syndrome virus (EDSV) can markedly decrease egg production in laying hens. Duck is the natural host of EDSV. EDSV derived from ducks abrogate egg drop in laying hens. We have previously confirmed that duck-derived EDSVs have a variety of replication activities in chick embryo liver (CEL) cells. However, it is currently unclear whether duck-derived EDSV could display tropism and adaptation in laying hens. This study assessed whether duck-derived EDSV can adapt to laying hens, and estimated the inducing factors. Complete genome sequences of duck-derived EDSVs (D11-JW-012, D11-JW-017, and D11-JW-032 isolates) with various replication efficiency in CEL cells and C10-GY-001 isolate causing disease in laying hens were analyzed to find their differences. Phylogenetic analysis of complete genome sequence revealed that C10-GY-001, D11-JW-032, and strain 127 virus as vaccine were clustered into the same group, with D11-JW-012 and D11-JW-017 clustered in another group. Comparison between D11-JW-012 isolate that poorly replicated and D11-JW-017 isolate that replicated well in CEL cells in same cluster revealed six amino acid differences on IVa2, DNA polymerase, endopeptidase, and DNA-binding protein. These amino acids might be key candidates enhancing cellular tropism in chicken. When the pathogenicities of these isolates in laying hens were compared, D11-JW-032 showed severe signs similar to 127 virus, D11-JW-017 showed intermediate signs, while D11-JW-012 showed almost no sign. Eleven amino acids differed between D11-JW-032 and D11-JW-017, and 17 amino acids were different between D11-JW-032 and D11-JW-012. These results suggest that EDSVs derived from ducks have various pathogenicities in laying hens. Key amino acid candidates might have altered their affinity to tropism of laying hens, causing difference pathogenicities.

Effect of excess dietary L-valine on laying hen performance, egg quality, serum free amino acids, immune function and antioxidant enzyme activity.

PubMed

Azzam, M M M; Dong, X Y; Dai, L; Zou, X T

2015-01-01

1. The aim of this study was to evaluate the tolerance of laying hens for an excessive L-valine (L-val) supply on laying performance, egg quality, serum free amino acids, immune function and antioxidant enzyme activities of laying hens. 2. A total of 720 HyLine Brown hens were allocated to 5 dietary treatment groups, each of which included 6 replicates of 24 hens, from 40 to 47 weeks of age. Graded amounts of L-val were added to the basal diet to achieve concentrations of 0 (control), 1, 2, 3 and 4 g/kg, respectively, in the experimental diets. 3. Supplementing the diet with L-val did not affect egg production, egg mass, egg weight, feed conversion ratio (FCR) or egg quality. The average daily feed intake response to supplemental L-val was quadratic and was maximised at 2.0 g L-val/kg diet. No differences were observed for total protein, total amino acids, blood urea nitrogen (BUN), uric acid, lactate dehydrogenase (LDH), alkaline phosphatase (AKP), Ca and P concentrations among the treatments. 4. Serum albumin concentration increased significantly in response to supplemental L-val and was also maximised at 2.0 g/kg. In addition, serum glucose increased quadratically to peak at 2.0 g L-val/kg diet. Serum free valine increased as L-val concentration increased to 2.0 g/kg diet and then decreased linearly. 5. Supplementation of L-val did not affect the serum concentrations of total antioxidative capability (T-AOC), superoxide dismutase (SOD) and malondialdehyde (MDA). L-val supplementation did not affect the concentrations of immunoglobulins IgG, IgA, IgM and complements (C3 and C4). Serum concentration of triiodothyronine (T3) increased significantly at 2.0 g L-val/kg diet. 6. It is concluded that high concentrations of L-val are tolerated and can be successfully supplemented into diets without detrimental effects on laying performance or immune function of laying hens.

Effects of adding aqueous extract of Tribulus terrestris to diet on productive performance, egg quality characteristics, and blood biochemical parameters of laying hens reared under low ambient temperature (6.8 ± 3 °C).

PubMed

Akbari, Mohsen; Torki, Mehran

2016-06-01

A study was conducted using 144 laying hens to evaluate the effects of adding aqueous extract of Tribulus terrestris to diets on productive performance, egg quality traits, and some blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C). The birds were randomly assigned to each of four dietary treatments (C, T1, T2, and T3) with six replicate cages of six birds. Diet inclusion of aqueous extract of T. terrestris at the rate of 10, 20, and 30 ml/Lit offered to groups T1, T2, and T3, respectively, while group C served as the control diet with no addition. Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 42-day trial period. The EP and EM increased, whereas FCR decreased (P < 0.001) in the hens fed the extract-included diet as compared to those fed the basal diet. The serum content of cholesterol decreased and the thickness of egg shell increased in the hens fed the T2 and T3 diet compared to those fed the basal diet. Overall from the results of the present experiment, it can be concluded that diet supplementation with aqueous extract of T. terrestris has beneficial effects on productive performance of laying hens reared under cold stress condition.

Effects of experimentally sustained elevated testosterone on incubation behaviour and reproductive success in female great tits (Parus major).

PubMed

de Jong, Berber; Lens, Luc; Amininasab, Seyed Mehdi; van Oers, Kees; Darras, Veerle M; Eens, Marcel; Pinxten, Rianne; Komdeur, Jan; Groothuis, Ton G G

2016-05-01

In many seasonally breeding birds, female and male testosterone (T) levels peak at the start of the breeding season, coinciding with pair bonding and nesting activities. Shortly after the onset of egg laying, T levels slowly decline to baseline levels in both sexes, but more rapidly so in females. During this period, T in males may still function to facilitate territorial behaviour, mate guarding and extra pair copulations, either via short lasting peaks or elevated basal levels of the hormone. In some species, however, males become insensitive to increased T after the onset of egg laying. It has been postulated that in these species bi-parental care is essential for offspring survival, as T is known to inhibit paternal care. However, only very few studies have analysed this for females. As females are heavily involved in parental care, they too might become insensitive to T after egg laying. Alternatively, because territorial defence, mate guarding and extra pair copulations are expected to be less important for females than for males, they may not have had the need to evolve a mechanism to become insensitive to T during the period of maternal care, because their natural T levels are never elevated during this part of the breeding season anyway. We tested these alternative hypotheses in female great tits (Parus major). Male great tits have previously been shown to be insensitive to T after egg laying with regard to nestling feeding behaviour (but not song rate). When females had started nest building, we experimentally elevated their T levels up to the nestling feeding phase, and measured incubation behaviour (only females incubate) and reproductive success. T did not significantly affect nest building or egg laying behaviour, although egg laying tended to be delayed in T females. Females with experimentally enhanced T maintained lower temperature during incubation but did not spend less time incubating. This might explain the reduced hatching success of their eggs, smaller brood size and lower number of fledglings we found in this study. As in this species T-dependent behaviour by females during the phase of parental care is not needed, the results support the hypothesis that in this species the need for selection in favour of T-insensitivity did not occur. Copyright © 2016 Elsevier Inc. All rights reserved.

Ovarian development in a primitively eusocial wasp: social interactions affect behaviorally dominant and subordinate wasps in opposite directions relative to solitary females.

PubMed

Shukla, Shantanu; Pareek, Vidhi; Gadagkar, Raghavendra

2014-07-01

In many primitively eusocial wasp species new nests are founded either by a single female or by a small group of females. In the single foundress nests, the lone female develops her ovaries, lays eggs as well as tends her brood. In multiple foundress nests social interactions, especially dominance-subordinate interactions, result in only one 'dominant' female developing her ovaries and laying eggs. Ovaries of the remaining 'subordinate' cofoundresses remain suppressed and these individuals function as workers and tend the dominant's brood. Using the tropical, primitively eusocial polistine wasp Ropalidia marginata and by comparing wasps held in isolation and those kept as pairs in the laboratory, we demonstrate that social interactions affect ovarian development of dominant and subordinate wasps among the pairs in opposite directions, suppressing the ovaries of the subordinate member of the pair below that of solitary wasps and boosting the ovaries of dominant member of the pair above that of solitary females. In addition to being of physiological interest, such mirror image effects of aggression on the ovaries of the aggressors and their victims, suggest yet another mechanism by which subordinates can enhance their indirect fitness and facilitate the evolution of worker behavior by kin selection. Copyright © 2014 Elsevier B.V. All rights reserved.

Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light

NASA Astrophysics Data System (ADS)

Horváth, Gábor; Majer, József; Horváth, Loránd; Szivák, Ildikó; Kriska, György

2008-11-01

Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color of reflected light.

Ventral polarization vision in tabanids: horseflies and deerflies (Diptera: Tabanidae) are attracted to horizontally polarized light.

PubMed

Horváth, Gábor; Majer, József; Horváth, Loránd; Szivák, Ildikó; Kriska, György

2008-11-01

Adult tabanid flies (horseflies and deerflies) are terrestrial and lay their eggs onto marsh plants near bodies of fresh water because the larvae develop in water or mud. To know how tabanids locate their host animals, terrestrial rendezvous sites and egg-laying places would be very useful for control measures against them, because the hematophagous females are primary/secondary vectors of some severe animal/human diseases/parasites. Thus, in choice experiments performed in the field we studied the behavior of tabanids governed by linearly polarized light. We present here evidence for positive polarotaxis, i.e., attraction to horizontally polarized light stimulating the ventral eye region, in both males and females of 27 tabanid species. The novelty of our findings is that positive polarotaxis has been described earlier only in connection with the water detection of some aquatic insects ovipositing directly into water. A further particularity of our discovery is that in the order Diptera and among blood-sucking insects the studied tabanids are the first known species possessing ventral polarization vision and definite polarization-sensitive behavior with known functions. The polarotaxis in tabanid flies makes it possible to develop new optically luring traps being more efficient than the existing ones based on the attraction of tabanids by the intensity and/or color of reflected light.

2-Hydroxy-4-Methylselenobutanoic Acid as New Organic Selenium Dietary Supplement to Produce Selenium-Enriched Eggs.

PubMed

Tufarelli, V; Ceci, E; Laudadio, V

2016-06-01

Food-based strategies need to be developed to improve the selenium (Se) status of individuals. The aim of this study was to evaluate the effects of a new organic Se [2-hydroxy-4-methylselenobutanoic acid (HMSeBA)] on selected performance criteria and Se deposition in egg of laying hens. Isa Brown laying hens, 18 weeks of age were randomly allocated to two dietary treatments and fed for 10 weeks. The hens were fed two corn-soybean meal-based diets comprising a control basal diet without Se supplementation and a test diet supplemented with Se at 0.2 mg/kg from HMSeBA. No difference was observed among dietary treatments on feed intake, egg weight and laying rate, whereas egg yolk fatty acid profile and vitamin E content were positively influenced by HMSeBA supplementation. Hens fed Se-supplemented diet exhibited greater (P < 0.001) egg yolk total Se contents, which averaged 21.2 mg/100 g dry matter (DM) compared to control diet (11.7 mg/100 g DM). Our results suggested that HMSeBA as Se supplement influences positively egg yolk quality without affecting hens' productive traits. Moreover, HMSeBA offers an efficient alternative to fortify eggs with Se, which can consequently lead to greater supply of Se for humans.

Ancient origin and maternal inheritance of blue cuckoo eggs.

PubMed

Fossøy, Frode; Sorenson, Michael D; Liang, Wei; Ekrem, Torbjørn; Moksnes, Arne; Møller, Anders P; Rutila, Jarkko; Røskaft, Eivin; Takasu, Fugo; Yang, Canchao; Stokke, Bård G

2016-01-12

Maternal inheritance via the female-specific W chromosome was long ago proposed as a potential solution to the evolutionary enigma of co-existing host-specific races (or 'gentes') in avian brood parasites. Here we report the first unambiguous evidence for maternal inheritance of egg colouration in the brood-parasitic common cuckoo Cuculus canorus. Females laying blue eggs belong to an ancient (∼2.6 Myr) maternal lineage, as evidenced by both mitochondrial and W-linked DNA, but are indistinguishable at nuclear DNA from other common cuckoos. Hence, cuckoo host races with blue eggs are distinguished only by maternally inherited components of the genome, which maintain host-specific adaptation despite interbreeding among males and females reared by different hosts. A mitochondrial phylogeny suggests that blue eggs originated in Asia and then expanded westwards as female cuckoos laying blue eggs interbred with the existing European population, introducing an adaptive trait that expanded the range of potential hosts.

Influence of fine-scale habitat structure on nest-site occupancy, laying date and clutch size in Blue Tits Cyanistes caeruleus

NASA Astrophysics Data System (ADS)

Amininasab, Seyed Mehdi; Vedder, Oscar; Schut, Elske; de Jong, Berber; Magrath, Michael J. L.; Korsten, Peter; Komdeur, Jan

2016-01-01

Most birds have specific habitat requirements for breeding. The vegetation structure surrounding nest-sites is an important component of habitat quality, and can have large effects on avian breeding performance. We studied 13 years of Blue Tit Cyanistes caeruleus population data to determine whether characteristics of vegetation structure predict site occupancy, laying date and number of eggs laid. Measurements of vegetation structure included the density of English Oak Quercus robur, European Beech Fagus sylvatica, and other deciduous, coniferous and non-coniferous evergreen trees, within a 20-m radius of nest-boxes used for breeding. Trees were further sub-divided into specific classes of trunk circumferences to determine the densities for different maturity levels. Based on Principal Component Analysis (PCA), we reduced the total number of 17 measured vegetation variables to 7 main categories, which we used for further analyses. We found that the occupancy rate of sites and the number of eggs laid correlated positively with the proportion of deciduous trees and negatively with the density of coniferous trees. Laying of the first egg was advanced with a greater proportion of deciduous trees. Among deciduous trees, the English Oak appeared to be most important, as a higher density of more mature English Oak trees was associated with more frequent nest-box occupancy, a larger number of eggs laid, and an earlier laying start. Furthermore, laying started earlier and more eggs were laid in nest-boxes with higher occupancy rates. Together, these findings highlight the role of deciduous trees, particularly more mature English Oak, as important predictors of high-quality preferred habitat. These results aid in defining habitat quality and will facilitate future studies on the importance of environmental quality for breeding performance.

Selective oviposition of the mayfly Baetis bicaudatus.

PubMed

Encalada, Andrea C; Peckarsky, Barbara L

2006-06-01

Selective oviposition can have important consequences for recruitment limitation and population dynamics of organisms with complex life cycles. Temporal and spatial variation in oviposition may be driven by environmental or behavioral constraints. The goals of this study were to: (1) develop an empirical model of the substrate characteristics that best explain observed patterns of oviposition by Baetis bicaudatus (Ephemeroptera), whose females lay eggs under rocks protruding from high-elevation streams in western Colorado; and (2) test experimentally selective oviposition of mayfly females. We surveyed the number and physical characteristics of potential oviposition sites, and counted the number and density of egg masses in different streams of one watershed throughout two consecutive flight seasons. Results of surveys showed that variability in the proportion of protruding rocks with egg masses and the density of egg masses per rock were explained primarily by seasonal and annual variation in hydrology, and variation in geomorphology among streams. Moreover, surveys and experiments showed that females preferred to oviposit under relatively large rocks located in places with high splash associated with fast current, which may provide visual, mechanical or both cues to females. Experiments also showed that high densities of egg masses under certain rocks were caused by rock characteristics rather than behavioral aggregation of ovipositing females. While aggregations of egg masses provided no survival advantage, rocks selected by females had lower probabilities of desiccating during egg incubation. Our data suggest that even when protruding rocks are abundant, not all rocks are used as oviposition sites by females, due to female selectivity and to differences in rock availability within seasons, years, or streams depending on variation in climate and hydrogeomorphology. Therefore, specialized oviposition behavior combined with variation in availability of quality oviposition substrata has the potential to limit recruitment of this species.

Effects of dietary L-arginine on laying performance and antioxidant capacity of broiler breeder hens, eggs, and offspring during the late laying period.

PubMed

Duan, Xiaoxue; Li, Feng; Mou, Shaoyang; Feng, Jiawei; Liu, Peifeng; Xu, Liangmei

2015-12-01

The effects of maternal L-arginine supplementation on laying performance and the antioxidant capacity of broiler breeder hens, egg yolk, and their one-day-old offspring were investigated. In a 9 wk experiment, 210 60-week-old Arbor Acres healthy female broiler breeders were randomly divided into 5 treatments with 6 replicates of 7 females and fed a corn and soybean meal diet with 5 arginine levels (0.96%, 1.16%, 1.36%, 1.56%, and 1.76% digestible arginine). Laying performance and anti-oxidant capacity of broiler breeder hens, eggs, and offspring were evaluated. Digestible arginine level in the broiler breeder diet had a significant effect on the laying rate (linear and quadratic effect, P<0.0001). The highest laying rate was obtained when the diet with 1.36% digestible arginine was fed. There was a significant effect of digestible arginine level in the broiler breeder diet on the total antioxidant capacity (T-AOC) levels and methane dicarboxylic aldehyde (MDA) concentration in the broiler breeder serum, egg yolk and serum, and liver and breast of one-day-old offspring (linear and quadratic effect, P<0.05). The T-AOC level was highest and the MDA concentration lowest in all tissues when a diet with 1.36% digestible arginine was fed. No difference in glutathione peroxidase (GSH-PX) activity in the broiler breeder serum was observed. There were significant effects of digestible arginine level in the broiler breeder diet on the GSH-PX activity of the egg yolk (linear effect, P<0.01; quadratic effect, P<0.05) and serum, liver, and breast of one-day-old offspring (linear and quadratic effect, P≤0.01). The GSH-PX activity in all tissues measured in this experiment was highest when the dietary digestible arginine was 1.36%. These results indicate that the diet with 1.36% digestible arginine (1,972 mg/d) is optimal to satisfy the nutritional needs of a female broiler breeder during the late laying period.

Effect of varying concentrations of dietary crude protein and metabolizable energy on laying performance of Pearl Grey guinea fowl hens.

PubMed

Nahashon, S N; Adefope, N A; Amenyenu, A; Wright, D

2007-08-01

This study was conducted to evaluate optimum dietary concentrations of ME and CP for egg production performance of the Pearl Gray guinea fowl laying hens. In a 2 x 3 factorial arrangement, 360 Pearl Gray guinea fowl replacement pullets (22 wk of age) were randomly assigned to experimental diets with 2,800 and 2,900 kcal of ME/kg of diet, each containing 14, 16, and 18% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Experimental birds were raised in laying cages and received 16 h of light throughout the study period. The birds were observed for feed consumption, hen-day egg production (HDEP), egg weight (EW), egg mass (EM), feed conversion ratio, internal egg quality, shell thickness (ST), and BW at the end of each 28-d lay period at 26 to 50 wk of age and at 62 to 86 wk of age. Mortality was recorded as it occurred. Mean HDEP, EW, EM, and ST were higher (P < 0.05) in hens receiving diets with 2,800 kcal of ME/kg of feed than those fed diets containing 2,900 kcal of ME/kg of diet. Hens on 14% CP diets also exhibited higher (P < 0.05) HDEP, EM, and ST than those fed diets containing 16 and 18% CP diets. Mean feed conversion ratio of birds on 2,800 kcal of ME/kg of diet and 14% CP diets were significantly lower than those of hens on other dietary treatments. Differences in feed consumption, EW, internal egg quality, BW, and mortality among dietary ME and CP concentrations were not significant (P > 0.05). Overall, diets composed of 2,800 kcal of ME/kg of diet and 14% CP were utilized more efficiently by the Pearl Gray guinea fowl laying hens at 26 to 50 and 62 to 86 wk of age.

Regulation of egg quality and lipids metabolism by Zinc Oxide Nanoparticles.

PubMed

Zhao, Yong; Li, Lan; Zhang, Peng-Fei; Liu, Xin-Qi; Zhang, Wei-Dong; Ding, Zhao-Peng; Wang, Shi-Wen; Shen, Wei; Min, Ling-Jiang; Hao, Zhi-Hui

2016-04-01

This investigation was designed to explore the effects of Zinc Oxide Nanoparticles (ZnO NP) on egg quality and the mechanism of decreasing of yolk lipids. Different concentration of ZnO NP and ZnSO4 were used to treat hens for 24 weeks. The body weight and egg laying frequency were recorded and analyzed. Albumen height, Haugh unit, and yolk color score were analyzed by an Egg Multi Tester. Breaking strength was determined by an Egg Force Reader. Egg shell thickness was measured using an Egg Shell Thickness Gouge. Shell color was detected by a spectrophotometer. Egg shape index was measured by Egg Form Coefficient Measuring Instrument. Albumen and yolk protein was determined by the Kjeldahl method. Amino acids were determined by an amino acids analyzer. Trace elements Zn, Fe, Cu, and P (mg/kg wet mass) were determined in digested solutions using Inductively Coupled Plasma-Optical Emission Spectrometry. TC and TG were measured using commercial analytical kits. Yolk triglyceride, total cholesterol, pancreatic lipase, and phospholipids were determined by appropriate kits. β-carotene was determined by spectrophotometry. Lipid metabolism was also investigated with liver, plasma, and ovary samples. ZnO NP did not change the body weight of hens during the treatment period. ZnO NP slowed down egg laying frequency at the beginning of egg laying period but not at later time. ZnO NP did not affect egg protein or water contents, slightly decreased egg physical parameters (12 to 30%) and trace elements (20 to 35%) after 24 weeks treatment. However, yolk lipids content were significantly decreased by ZnO NP (20 to 35%). The mechanism of Zinc oxide nanoparticles decreasing yolk lipids was that they decreased the synthesis of lipids and increased lipid digestion. These data suggested ZnO NP affected egg quality and specifically regulated lipids metabolism in hens through altering the function of hen's ovary and liver. © 2016 Poultry Science Association Inc.

Impact of vaccination on infection with Vietnam H5N1 high pathogenicity avian influenza virus in hens and the eggs they lay

USDA-ARS?s Scientific Manuscript database

Highly pathogenic avian influenza virus (HPAIV) infections in chickens produce a negative impact on egg production, and virus is deposited on surface and internal contents of eggs. Previously, vaccination maintained egg production and reduced egg contamination when challenged with a North American H...

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.

Effect of increasing levels of apparent metabolizable energy on laying hens in barn system.

PubMed

Kang, Hwan Ku; Park, Seong Bok; Jeon, Jin Joo; Kim, Hyun Soo; Park, Ki Tae; Kim, Sang Ho; Hong, Eui Chul; Kim, Chan Ho

2018-04-12

This experiment was to investigate the effect of increasing levels of apparent metabolizable energy (AMEn) on the laying performance, egg quality, blood parameter, blood biochemistry, intestinal morphology, and apparent total tract digestibility (ATTD) of energy and nutrients in diets fed to laying hens. A total of three-hundred twenty 33-week-old Hy-Line Brown laying hens (Gallus domesticus) were evenly assigned to four experimental diets of 2,750, 2,850, 2,950, and 3,050 kcal AMEn/kg in floor with deep litter of rice hulls. There were four replicates of each treatment, each consisting of 20 birds in a pen. AMEn intake was increased (linear, p < 0.05) with inclusion level of AMEn in diets increased. Feed intake and feed conversion ratio were improved (linear, p < 0.01), but hen-day egg production tended to be increased as increasing level of AMEn in diets increased. During the experiment, leukocyte concentration and blood biochemistry (total cholesterol, triglyceride, glucose, total protein, calcium, asparate aminotransferase (AST), and alanine transferase (ALT) were not influenced by increasing level of AMEn in diets. Gross energy and ether extract were increased (linear, p < 0.01) with inclusion level of AMEn in diets increased. Laying hens fed high AMEn diet (i.e., 3,050 kcal/kg in the current experiment) tended to overconsume energy with a positive effect on feed intake, feed conversion ratio, nutrient digestibility, and intestinal morphology but not in egg production and egg mass.

Justifying an ideal first pregnancy age: Vernacular science knowledge and the facilitation of lay argument.

PubMed

Jensen, Robin E; Blumling, Allison N

2018-04-01

Members of the lay public often draw from vernacular science knowledge-or metaphors, images, and terms related to technical science-to make normative assessments about behavior. Yet, little is known about vernacular science knowledge in terms of its forms and functions. In a national survey, US adults ( N = 688) were asked to identify an ideal age for first pregnancy, and to explain their decision. Participants drew from arguments related to hormonal processes, the language of risk, and the quality and quantity of "eggs" to navigate and identify an ideal timeline for first pregnancy. Their responses illustrated patterns of justification that involved the (a) employment of scientific concepts as heuristic cues for critical analysis, (b) conflation of details, and (c) synecdochal explication. These findings reveal some of the key ways in which vernacular science knowledge may shape the trajectory of lay argument in a range of contexts.

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.

Does contrast between eggshell ground and spot coloration affect egg rejection?

PubMed

Dainson, Miri; Hauber, Mark E; López, Analía V; Grim, Tomáš; Hanley, Daniel

2017-08-01

Obligate avian brood parasitic species impose the costs of incubating foreign eggs and raising young upon their unrelated hosts. The most common host defence is the rejection of parasitic eggs from the nest. Both egg colours and spot patterns influence egg rejection decisions in many host species, yet no studies have explicitly examined the role of variation in spot coloration. We studied the American robin Turdus migratorius, a blue-green unspotted egg-laying host of the brown-headed cowbird Molothrus ater, a brood parasite that lays non-mimetic spotted eggs. We examined host responses to model eggs with variable spot coloration against a constant robin-mimetic ground colour to identify patterns of rejection associated with perceived contrast between spot and ground colours. By using avian visual modelling, we found that robins were more likely to reject eggs whose spots had greater chromatic (hue) but not achromatic (brightness) contrast. Therefore, egg rejection decision rules in the American robin may depend on the colour contrast between parasite eggshell spot and host ground coloration. Our study also suggests that egg recognition in relation to spot coloration, like ground colour recognition, is tuned to the natural variation of avian eggshell spot colours but not to unnatural spot colours.

Parasitic Cape honeybee workers, Apis mellifera capensis, evade policing

NASA Astrophysics Data System (ADS)

Martin, Stephen J.; Beekman, Madeleine; Wossler, Theresa C.; Ratnieks, Francis L. W.

2002-01-01

Relocation of the Cape honeybee, Apis mellifera capensis, by bee-keepers from southern to northern South Africa in 1990 has caused widespread death of managed African honeybee, A. m. scutellata, colonies. Apis mellifera capensis worker bees are able to lay diploid, female eggs without mating by means of automictic thelytoky (meiosis followed by fusion of two meiotic products to restore egg diploidy), whereas workers of other honeybee subspecies are able to lay only haploid, male eggs. The A. m. capensis workers, which are parasitizing and killing A. m. scutellata colonies in northern South Africa, are the asexual offspring of a single, original worker in which the small amount of genetic variation observed is due to crossing over during meiosis (P. Kryger, personal communication). Here we elucidate two principal mechanisms underlying this parasitism. Parasitic A. m. capensis workers activate their ovaries in host colonies that have a queen present (queenright colonies), and they lay eggs that evade being killed by other workers (worker policing)-the normal fate of worker-laid eggs in colonies with a queen. This unique parasitism by workers is an instance in which a society is unable to control the selfish actions of its members.

Techniques for identifying predators of goose nests

USGS Publications Warehouse

Anthony, R. Michael; Grand, J.B.; Fondell, T.F.; Miller, David A.

2006-01-01

We used cameras and artificial eggs to identify nest predators of dusky Canada goose Branta canadensis occidentalis nests during 1997-2000. Cameras were set up at 195 occupied goose nests and 60 artificial nests. We placed wooden eggs and domestic goose eggs that were emptied and then filled with wax or foam in an additional 263 natural goose nests to identify predators from marks in the artificial eggs. All techniques had limitations, but each correctly identified predators and estimated their relative importance. Nests with cameras had higher rates of abandonment than natural nests, especially during laying. Abandonment rates were reduced by deploying artificial eggs late in laying and reducing time at nests. Predation rates for nests with cameras were slightly lower than for nests without cameras. Wax-filled artificial eggs caused mortality of embryos in natural nests, but were better for identifying predator marks at artificial nests. Use of foam-filled artificial eggs in natural nests was the most cost effective means of monitoring nest predation. ?? Wildlife Biology (2006).

Hit or Miss: Fertilization Outcomes of Natural Inseminations by Japanese Quail

PubMed Central

Adkins-Regan, Elizabeth

2015-01-01

Variation in fertilization success underlies sexual selection, yet mating does not guarantee fertilization. The relationship between natural inseminations and fertilization success is essential for understanding sexual selection, yet that relationship and its underlying mechanisms are poorly understood in sperm-storing vertebrates such as birds. Here the relationship is analyzed in mating trials using Japanese quail (Coturnix japonica), which show striking variation in the fertilizing success of inseminations. Failures of males’ inseminations to fertilize eggs were mainly due to failures prior to sperm-egg contact. Fertilization probabilities on any given day were unrelated to whether the female had laid an egg the previous day, arguing against stimulation of sperm release from sperm storage tubules by the events of the daily egg-laying cycle. Instead, an unfertilized egg laid between two fertilized eggs predicted a longer sperm storage interval. Both sexes gained similar numbers of fertilized eggs by mating with a second partner the next day, but males, unlike females in a previous study, did not gain by having two females to mate with at the same time. Instead, they were both behaviorally and sperm limited, whereas females gain by mating twice in quick succession. Even double inseminations often failed to fertilize any eggs, and multiple matings would be needed for an entire clutch to be fertilized with high certainty. Paradoxically, this low and probabilistic fertilization success co-occurs with other notable characteristics of male quail suggestive of past sexual selection for increased success, including vigorous copulatory behavior, forced copulations, foamy secretion aiding in sperm competition, large testes and unusual sperm morphology. PMID:26222780

Effect of rearing factors on the prevalence of floor eggs, cloacal cannibalism and feather pecking in commercial flocks of loose housed laying hens.

PubMed

Gunnarsson, S; Keeling, L J; Svedberg, J

1999-03-01

1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (P<0-001). Furthermore, early access to perches decreased the prevalence of cloacal cannibalism during the production period, odds ratio 0-46 (P=0.03). 5. No other factor had a significant effect in these models. Although it was not significant, early access to litter had a non-significant tendency to reduce the prevalence of feather pecking.

Effect of fermented earthworm cast on egg production and egg quality as well as removal of odor in feces from egg laying hens.

PubMed

Yoon, Jae-Sung; Park, Byung-Sung

2016-07-01

The objective of the present study was to determine the effect of feeding fermented earthworm casts (EEC) to layers on egg-laying performance, blood lipid profiles, cecal microflora, and fecal odor removing performance. A total of 200 Hyline Brown layer chicks at 33-week-old were used in this study. They were randomly assigned to two numerically equal groups with 100 replications per treatment for 10 weeks. All the birds were caged individually. The control group was not treated with EEC. The EEC group was treated with top dressing containing 3.5% EEC. The present study revealed that egg production and egg weight were increased after feeding diet containing EEC at the top dressing level. Haugh unit, eggshell thickness, and eggshell breaking strength of EEC group were higher than those of control group. Egg yolk was determined for fatty acid profiling. It was found that EEC group had higher ratio of unsaturated- to saturated fatty acid as compared to control group. Lower ratios of n-6 to n-3 fatty acids were found in the egg yolk of EEC group. Plasma triglyceride and total cholesterol contents were lower in the EEC group. However, high density lipoprotein-cholesterol content was higher in the EEC group as compared to that in control group. The number of cecal Lactobacillus was increased while the population of Escherichia coli and coliform bacteria decreased in the EEC group. Fecal ammonia and hydrogen sulfide contents were lower in the EEC group as compared to those in control group. Taken together, these results suggested that EEC could improve egg production and egg quality. In addition, it could remove odour from laying-hen manure.

Chemical Compositions of Egg Yolks and Egg Quality of Laying Hens Fed Prebiotic, Probiotic, and Synbiotic Diets.

PubMed

Tang, Shirley Gee Hoon; Sieo, Chin Chin; Kalavathy, Ramasamy; Saad, Wan Zuhainis; Yong, Su Ting; Wong, Hee Kum; Ho, Yin Wan

2015-08-01

A 16-wk feeding experiment was conducted to investigate the effects of a prebiotic, isomaltooligosaccharide (IMO), a probiotic, PrimaLac®, and their combination as a synbiotic on the chemical compositions of egg yolks and the egg quality of laying hens. One hundred and sixty 16-wk-old Hisex Brown pullets were randomly assigned to 4 dietary treatments: (i) basal diet (control), (ii) basal diet + 1% IMO (PRE), (iii) basal diet + 0.1% PrimaLac® (PRO), and (iv) basal diet + 1% IMO + 0.1% PrimaLac® (SYN). PRE, PRO, or SYN supplementation not only significantly (P < 0.05) decreased the egg yolk cholesterol (24- and 28-wk-old) and total saturated fatty acids (SFA; 28-, 32-, and 36-wk-old), but also significantly (P < 0.05) increased total unsaturated fatty acids (UFA; 28-, 32-, and 36-wk-old), total omega 6 and polyunsaturated fatty acids (PUFA), including linoleic and alpha-linolenic acid levels in the eggs (28-wk-old). However, the total lipids, carotenoids, and tocopherols in the egg yolks were similar among all dietary treatments in the 24-, 28-, 32-, and 36-wk-old hens. Egg quality (Haugh unit, relative weights of the albumen and yolk, specific gravity, shell thickness, and yolk color) was not affected by PRE, PRO, or SYN supplementation. The results indicate that supplementations with IMO and PrimaLac® alone or in combination as a synbiotic might be useful for improving the cholesterol content and modifying the fatty acid compositions of egg yolk without affecting the quality of eggs from laying hens between 24 and 36 wk of age. © 2015 Institute of Food Technologists®

Surface hydrocarbons of queen eggs regulate worker reproduction in a social insect

PubMed Central

Endler, Annett; Liebig, Jürgen; Schmitt, Thomas; Parker, Jane E.; Jones, Graeme R.; Schreier, Peter; Hölldobler, Bert

2004-01-01

A hitherto largely unresolved problem in behavioral biology is how workers are prevented from reproducing in large insect societies with high relatedness. Signals of the queen are assumed to inform the nestmates about her presence in the colony, which leads to indirect fitness benefits for workers. In the ant Camponotus floridanus, we found such a signal located on queen-laid eggs. In groups of workers that were regularly provided with queen-laid eggs, larvae, and cocoons, with larvae and cocoons alone, or with no brood, only in the groups with queen-laid eggs did workers not lay eggs. Thus, the eggs seem to inform the nestmates about the queen's presence, which induces workers to refrain from reproducing. The signal on queen-laid eggs is presumably the same that enables workers to distinguish between queen- and worker-laid eggs. Despite their viability, the latter are destroyed by workers when given a choice between both types. Queen- and worker-laid eggs differ in their surface hydrocarbons in a way similar to the way fertile queens differ from workers in the composition of their cuticular hydrocarbons. When we transferred hydrocarbons from the queen cuticle to worker-laid eggs, the destruction of those eggs was significantly mitigated. We conclude that queen-derived hydrocarbon labels inform workers about the presence of a fertile queen and thereby regulate worker reproduction. PMID:14993614

Control and monitoring of Salmonella in egg-laying chickens

USDA-ARS?s Scientific Manuscript database

Contaminated eggs have been internationally significant sources for the transmission of Salmonella infection to humans for several decades. Both the public and private sectors have invested substantial resources in comprehensive risk reduction and monitoring programs for Salmonella in commercial egg...

Microbiology of Shell Egg Production in the United States

USDA-ARS?s Scientific Manuscript database

A significant proportion of human illnesses caused by Salmonella are linked to the consumption of contaminated eggs. Substantial government and industry resources have been committed to comprehensive Salmonella testing and risk reduction programs for commercial egg-laying flocks. The implementation ...

Variation in egg size of the northern pintail

USGS Publications Warehouse

Flint, Paul L.; Grand, James B.

1996-01-01

Egg size is an important determinant of reproductive investment by birds. For many species, total investment in a clutch is limited by the size of stored reserves (Ankney and MacInnes 1978, Esler and Grand 1994a). Egg size determines the unit by which these stored reserves are partitioned. Individual females in most species of waterfowl show a high repeatability for egg size, implying that individual either cannot, or do not, alter their egg size in response to varying environmental conditions (batt and Prince 1979, Duncan 1987, Laurila and Hario 1988, Lessells et al 1989, Flint and Sedinger 1992). Thus differences in egg size appear to represent different reproductive strategies among individuals.Fitness can be measured by the number of offspring an individual contributes to a population. Egg size may be related to fitness in some species fo waterfowl as young from larger eggs are better able to survive extreme conditions (Ankney 1980, Thomas and Brown 1988). Birds laying larger clutches are almost always more fit as they fledge more young (Lessells 1986, Rockwell et al 1987, Flint 1993). These fitness patterns create the potential for a trade-off between clutch size and egg size where females laying large clutches of small eggs have the same fitness as females laying smaller clutches of large eggs. The fact that Northern Pintails (Anas acuta) utilize stored reserves (Mann and Sedinger 1993, esler and Grand 1994a) and have a high repeatability for egg size (i.e. egg size is fixed) (Duncan 1987), makes them candidates to engage in clutch size=egg size trade-offs (Rowher 1988, Rowher and Eisenhauer 1989). An inverse relationship between egg size and clutch size would be indicative of a phenotypic trade-off among these fitness components. Our goal in this study was to describe egg size variation in Northern Pintails (hereafter pintails) with regard to female age, body size, clutch size, year, initiation date, and nesting attempt. We compare our results to those from other populations of nesting pintails and discuss whether phenotypic clutch size-egg size tradeoffs exist for pintails.

Effects of carbohydrase enzyme supplementation on performance, eggshell quality, and bone parameters of laying hens fed on maize- and wheat-based diets.

PubMed

Olgun, Osman; Altay, Y; Yildiz, Alp O

2018-04-01

1. This study was conducted to determine the effects of enzyme supplementation of maize/wheat-based diets on the performance, egg quality, and serum and bone parameters of laying hens. 2. During the 12-week experimental period, a total of 72 laying hens aged 52 weeks were randomly distributed among 6 experimental groups. Each experimental group contained 4 replicates, each with three birds. The experiment was a randomised design consisting of a 3 × 2 factorial arrangement, with three levels of wheat substitution and two levels of enzyme (xylanase: 1500.00 U/kg, β-glucanase: 100 000 U/kg, cellulase: 1 000 000 U/kg, α-amylase: 160 000 U/kg) inclusion in the diet. Wheat replaced 0, 50, or 100% of maize with or without 1.0 g/kg enzyme supplementation in iso-nitrogenous and iso-caloric experimental diets. 3. Body weight, egg production, egg weight, egg mass, eggshell thickness, and the feed conversion ratio were adversely affected by the wheat-based diet. The eggshell quality parameters decreased with enzyme supplementation to the diet. 4. Wheat-based diets adversely affected calcium and phosphorus concentrations in the tibia, but the addition of the enzymes to the wheat-based diet prevented the negative effects of wheat-based diets on tibia mineralisation in laying hens. The wheat-based diets tended to reduce plasma mineral contents, and the addition of enzymes tended to affect plasma minerals and biomechanical properties of the tibia positively in laying hens. 5. These results indicate that wheat-based diets in aged laying hens adversely affected the mineral metabolism compared with maize-based diets, and the negative effects of wheat on bone mineralisation can be prevented by enzyme supplementation to the diets in laying hens.

Comparison of environmental and egg microbiology associated with conventional and free range laying hen management

USDA-ARS?s Scientific Manuscript database

Eggs from alternative production practices are a growing niche in the market. Meeting consumer requests for greater diversity in retail egg options has resulted in some unique challenges such as understanding the food safety implications of eggs from alternative production practices. A study was c...

Egg Speckling Patterns Do Not Advertise Offspring Quality or Influence Male Provisioning in Great Tits

PubMed Central

Stoddard, Mary Caswell; Fayet, Annette L.; Kilner, Rebecca M.; Hinde, Camilla A.

2012-01-01

Many passerine birds lay white eggs with reddish brown speckles produced by protoporphyrin pigment. However, the function of these spots is contested. Recently, the sexually selected eggshell coloration (SSEC) hypothesis proposed that eggshell color is a sexually selected signal through which a female advertises her quality (and hence the potential quality of her future young) to her male partner, thereby encouraging him to contribute more to breeding attempts. We performed a test of the SSEC hypothesis in a common passerine, the great tit Parus major. We used a double cross-fostering design to determine whether males change their provisioning behavior based on eggshell patterns they observe at the nest. We also tested the assumption that egg patterning reflects female and/or offspring quality. Because birds differ from humans in their color and pattern perception, we used digital photography and models of bird vision to quantify egg patterns objectively. Neither male provisioning nor chick growth was related to the pattern of eggs males observed during incubation. Although heavy females laid paler, less speckled eggs, these eggs did not produce chicks that grew faster. Therefore, we conclude that the SSEC hypothesis is an unlikely explanation for the evolution of egg speckling in great tits. PMID:22815730

Effect of γ-Aminobutyric Acid-producing Lactobacillus Strain on Laying Performance, Egg Quality and Serum Enzyme Activity in Hy-Line Brown Hens under Heat Stress.

PubMed

Zhu, Y Z; Cheng, J L; Ren, M; Yin, L; Piao, X S

2015-07-01

Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high γ-aminobutyric acid (GABA)-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164) at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i) 0 mg/kg, ii) 25 mg/kg, iii) 50 mg/kg, and iv) 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at 28.83±3.85°C and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05) by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05) than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009) and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to improve laying performance and egg quality in heat-stressed hens.

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

Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres

NASA Technical Reports Server (NTRS)

Kloek, G.; Winkle, L.

1979-01-01

Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres.

PubMed

Kloek, G; Winkle, L

1979-04-01

Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

Calcium homeostasis and vitamin D metabolism and expression in strongly calcifying laying birds.

PubMed

Bar, Arie

2008-12-01

Egg laying and shell calcification impose severe extra demands on ionic calcium (Ca2+) homeostasis; especially in birds characterized by their long clutches (series of eggs laid sequentially before a "pause day"). These demands induce vitamin D metabolism and expression. The metabolism of vitamin D is also altered indirectly, by other processes associated with increased demands for calcium, such as growth, bone formation and egg production. A series of intestinal, renal or bone proteins are consequently expressed in the target organs via mechanisms involving a vitamin D receptor. Some of these proteins (carbonic anhydrase, calbindin and calcium-ATPase) are also found in the uterus (eggshell gland) or are believed to be involved in calcium transport in the intestine or kidney (calcium channels). The present review deals with vitamin D metabolism and the expression of the above-mentioned proteins in birds, with special attention to the strongly calcifying laying bird.

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.

Sperm-attractant peptide influences the spermatozoa swimming behavior in internal fertilization in Octopus vulgaris.

PubMed

De Lisa, Emilia; Salzano, Anna Maria; Moccia, Francesco; Scaloni, Andrea; Di Cosmo, Anna

2013-06-15

Marine invertebrates exhibit both chemokinesis and chemotaxis phenomena, induced in most cases by the release of water-borne peptides or pheromones. In mollusks, several peptides released during egg-laying improve both male attraction and mating. Unlike other cephalopods, Octopus vulgaris adopts an indirect internal fertilization strategy. We here report on the identification and characterization of a chemoattractant peptide isolated from mature eggs of octopus females. Using two-chamber and time-lapse microscopy assays, we demonstrate that this bioactive peptide is able to increase sperm motility and induce chemotaxis by changing the octopus spermatozoa swimming behavior in a dose-dependent manner. We also provide evidence that chemotaxis in the octopus requires the presence of extracellular calcium and membrane protein phophorylation at tyrosine. This study is the first report on a sperm-activating factor in a non-free-spawning marine animal.

The effect of dietary supplementation of salts of organic acid on production performance of laying hens

PubMed Central

Dahiya, Ravinder; Berwal, Raj Singh; Sihag, Sajjan; Patil, Chandrashekhar Santosh; Lalit

2016-01-01

Aim: An experiment was conducted to evaluate the effect of supplementing different levels of salts of organic acid in the laying hen’s diet on their production performance and egg quality parameters during a period of 16-week. Materials and Methods: A total of 140 white leghorn laying hens at 24 weeks of age were randomly distributed to seven dietary treatment groups, i.e. T1 (control), T2 (0.5% sodium-butyrate), T3 (1.0% sodium-butyrate), T4 (1.5% sodium-butyrate), T5 (0.5% calcium-propionate), T6 (1.0% calcium-propionate) and T7 (1.5% calcium-propionate) consisting of 5 replications of 4 birds each in each treatment and housed in individual cages from 24 to 40 weeks of age. Feed intake, percent hen-day egg production, egg weight, egg mass production, feed conversion ratio (FCR), and economics of supplementation of salts of organic acids in layers’ ration were evaluated. Results: The dietary supplementation of salts of organic acids did not significantly affect the feed intake (g/day/hen) and body weight gain (g). Different levels of supplementation significantly (p<0.05) improved production performance (percent hen-day egg production and egg mass production) as compared to control group. FCR in terms of feed intake (kg) per dozen eggs was lowest (1.83±0.05) in T4 and feed intake (kg) per kg egg mass was lowest (2.87±0.05) in T5 as comparison to control (T1) group. Salts of organic acids supplementation resulted in significant (p<0.05) improvement in FCR. Egg weight was significantly (p<0.05) increased at 0.5% level of salts of organic acids in the diet. The cumulative mean values of feed cost per dozen egg production were Rs. 44.14, 42.40, 42.85, 43.26, 42.57, 43.29 and 43.56 in treatment groups T1, T2, T3, T4, T5, T6 and T7, respectively, and reduction in feed cost per kg egg mass production for Rs. 0.52 and 0.99 in groups T2 and T5, respectively, in comparison to T1 group. Conclusions: It can be concluded that supplementation of salts of organic acids may improve persistency of lay, egg weight, and FCR. From economical point of view, egg production was more profitable at 0.5% level of sodium butyrate and 0.5% level of calcium propionate which reduced the feed cost per dozen eggs and per kg egg mass production without affecting the egg quality. PMID:28096625

Oviposition Site Selection by the Dengue Vector Aedes aegypti and Its Implications for Dengue Control

PubMed Central

Wong, Jacklyn; Stoddard, Steven T.; Astete, Helvio; Morrison, Amy C.; Scott, Thomas W.

2011-01-01

Background Because no dengue vaccine or antiviral therapy is commercially available, controlling the primary mosquito vector, Aedes aegypti, is currently the only means to prevent dengue outbreaks. Traditional models of Ae. aegypti assume that population dynamics are regulated by density-dependent larval competition for food and little affected by oviposition behavior. Due to direct impacts on offspring survival and development, however, mosquito choice in oviposition site can have important consequences for population regulation that should be taken into account when designing vector control programs. Methodology/Principal Findings We examined oviposition patterns by Ae. aegypti among 591 naturally occurring containers and a set of experimental containers in Iquitos, Peru. Using larval starvation bioassays as an indirect measure of container food content, we assessed whether females select containers with the most food for their offspring. Our data indicate that choice of egg-laying site is influenced by conspecific larvae and pupae, container fill method, container size, lid, and sun exposure. Although larval food positively influenced oviposition, our results did not support the hypothesis that females act primarily to maximize food for larvae. Females were most strongly attracted to sites containing immature conspecifics, even when potential competitors for their progeny were present in abundance. Conclusion/Significance Due to strong conspecific attraction, egg-laying behavior may contribute more to regulating Ae. aegypti populations than previously thought. If highly infested containers are targeted for removal or larvicide application, females that would have preferentially oviposited in those sites may instead distribute their eggs among other suitable, previously unoccupied containers. Strategies that kill mosquitoes late in their development (i.e., insect growth regulators that kill pupae rather than larvae) will enhance vector control by creating “egg sinks,” treated sites that exploit conspecific attraction of ovipositing females, but reduce emergence of adult mosquitoes via density-dependent larval competition and late acting insecticide. PMID:21532736

Sublethal Effects of ActiveGuard Exposure on Feeding Behavior and Fecundity of the Bed Bug (Hemiptera: Cimicidae).

PubMed

Jones, Susan C; Bryant, Joshua L; Sivakoff, Frances S

2015-05-01

Sublethal exposure to pesticides can alter insect behavior with potential for population-level consequences. We investigated sublethal effects of ActiveGuard, a permethrin-impregnated fabric, on feeding behavior and fecundity of bed bugs (Cimex lectularius L.) from five populations that ranged from susceptible to highly pyrethroid resistant. After exposure to ActiveGuard fabric or untreated fabric for 1 or 10 min, adult virgin female bed bugs were individually observed when offered a blood meal to determine feeding attempts and weight gain. Because bed bug feeding behavior is tightly coupled with its fecundity, all females were then mated, and the number of eggs laid and egg hatch rate were used as fecundity measures. We observed that pyrethroid-resistant and -susceptible bugs were not significantly different for all feeding and fecundity parameters. Bed bugs exposed to ActiveGuard for 10 min were significantly less likely to attempt to feed or successfully feed, and their average blood meal size was significantly smaller compared with individuals in all other groups. Independent of whether or not feeding occurred, females exposed to ActiveGuard for 10 min were significantly more likely to lay no eggs. Only a single female exposed to ActiveGuard for 10 min laid any eggs. Among the other fabric treatment-exposure time groups, there were no observable differences in egg numbers or hatch rates. Brief exposure of 10 min to ActiveGuard fabric appeared to decrease feeding and fecundity of pyrethroid-resistant and susceptible bed bugs, suggesting the potentially important role of sublethal exposure for the control of this ectoparasitic insect. © 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.

Room environment influence on eggshell bacterial levels of non-washed and washed eggs from caged and cage-free laying hens

USDA-ARS?s Scientific Manuscript database

The bacteria levels of non-washed and washed eggs obtained from caged and cage-free hens housed in either wire slats or shaving-covered pens were determined. On eight days (from 22 to 52 wk), 20 eggs were collected from each pen. Ten eggs/pen were washed with a commercial egg washing solution, whi...

Effects of the main cereal and type of fat of the diet on productive performance and egg quality of brown-egg laying hens from 22 to 54 weeks of age.

PubMed

Pérez-Bonilla, A; Frikha, M; Mirzaie, S; García, J; Mateos, G G

2011-12-01

The influence of the main cereal and type of supplemental fat in the diet on productive performance and egg quality of the eggs was studied in 756 brown-egg laying hens from 22 to 54 wk of age. The experiment was conducted as a completely randomized design with 9 treatments arranged factorially, with 3 cereals (dented corn, soft wheat, and barley) and 3 types of fat (soy oil, acidulated vegetable soapstocks, and lard). Each treatment was replicated 4 times (21 hens/replicate). All diets were formulated to have similar nutrient content, except for linoleic acid, which ranged from 0.8 to 3.4% depending on the combination of cereal and fat source used. This approach allows for the estimation of the minimum level of linoleic acid in the diets that maximizes egg weight. Productive performance and egg-quality traits were recorded every 28 d, and the BW of the hens was measured individually at the beginning and at the end of the experiment. No significant interactions between main factors were detected for any of the variables studied. Egg production, egg weight, and egg mass were not affected by dietary treatment. Body weight gain was higher (P < 0.05) for hens fed corn or wheat than for hens fed barley, and also higher for hens fed lard than for hens fed soy oil or acidulated vegetable soapstocks. Egg quality was not influenced by dietary treatment, except for yolk color, which was greater (P < 0.001) for hens fed corn than for hens fed wheat or barley, and greater for hens fed lard than for hens fed soy oil or acidulated vegetable soapstocks. We concluded that brown-egg laying hens do not need more than 1.0% of linoleic acid in their diet (1.16 g/hen per d) to maximize egg production and egg size. The 3 cereals and the 3 fat sources tested can replace each other in the diet provided that the linoleic acid requirements to maximize egg size are met.

9 CFR 146.22 - Participation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Commercial Table-Egg Layer Flocks § 146.22 Participation. (a) Participating commercial table-egg layer flocks... of subpart B of this part. (b) Commercial table-egg laying premises with fewer than 75,000 birds are...

Individual birds advance offspring hatching in response to increased temperature after the start of laying.

PubMed

Vedder, Oscar

2012-11-01

In seasonally reproducing organisms, timing reproduction to match food availability is key to individual fitness. Ambient temperature functions as an important cue for the timing of the food peak in temperate-zone birds. After laying start, individual birds may still improve synchrony between offspring hatching and food availability by adjusting the onset of incubation to most up-to-date cues about the development of the food source. However, it is unknown whether individuals respond to changes in temperature after the onset of laying, and whether individuals adjust incubation onset independent of clutch size. Here, I show in free-living blue tits (Cyanistes caeruleus) that experimental heating of nestboxes in the laying phase resulted in increased duration of nocturnal incubation bouts prior to clutch completion, leading to earlier hatching of eggs and increased hatching asynchrony. Experimental heating did not affect the number of laying gaps, egg volume and clutch size, nor were any carry-over effects on offspring detected. These results are best explained as a response to increased temperature acting as a cue for an advanced food-peak, rather than a relief of energetic constraints, because improved energetic conditions would not favour more hatching asynchrony. Other benefits cannot be excluded, since increased laying-phase incubation under warmer conditions may also help maintain egg viability. This study is the first to show that temperature has a causal effect on the time between clutch completion and hatching of the first offspring, indicating that behavioural adjustment to climate change can continue after laying start.

Insecticide toxicity to the borer Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae): developmental and egg-laying effects.

PubMed

Silva, R S; Arcanjo, L P; Soares, J R S; Ferreira, D O; Serrão, J E; Martins, J C; Costa, Á H; Picanço, M C

2018-04-01

Neoleucinodes elegantalis (Guenée) (Lepidoptera: Crambidae) is one of the major pests of solanaceous plants in South America. It is considered a great threat by the European and Mediterranean Plant Protection Organization due to the serious economic damage that it causes on tomato farms; therefore, controlling this pest is a challenging task in South America. Controlling N. elegantalis at the egg stage is the best way to prevent it from damaging crops; however, thorough studies about the effectiveness of chemicals on the different life stages of this insect pest are lacking. In this study, the effects of different chemical classes were evaluated on N. elegantalis adults, female oviposition behavior, larvae, eggs, and embryonic development. None of the tested insecticides demonstrated toxicity to the adults; however, the results showed that cartap hydrochloride affects oviposition behavior. Moreover, methomyl and cartap hydrochloride exhibited high toxicity against the eggs and larvae, with higher than 80% of mortality. These insecticides interrupted larval hatching and caused alterations in the chorion layer. Flubendiamide and deltamethrin demonstrated toxicity on N. elegantalis larvae; however, lufenuron, indoxacarb, methoxyfenozide, and chlorantraniliprole demonstrated low toxicity on both eggs and larvae, with lower than 70% of mortality. Fruit treated with cartap hydrochloride had a deterrent effect. The ovicidal activity revealed by methomyl and cartap hydrochloride might provide new approaches regarding insecticide effects on eggs. Methomyl, cartap hydrochloride, flubendiamide, and deltamethrin demonstrated toxicity on larvae. The evaluation of the chorion of the eggshell in this study has clarified the toxic effect of methomyl and cartap hydrochloride on eggs.

Experimental shifts in intraclutch egg color variation do not affect egg rejection in a host of a non-egg-mimetic avian brood parasite.

PubMed

Croston, Rebecca; Hauber, Mark E

2015-01-01

Avian brood parasites lay their eggs in the nests of other birds, and impose the costs associated with rearing parasitic young onto these hosts. Many hosts of brood parasites defend against parasitism by removing foreign eggs from the nest. In systems where parasitic eggs mimic host eggs in coloration and patterning, extensive intraclutch variation in egg appearances may impair the host's ability to recognize and reject parasitic eggs, but experimental investigation of this effect has produced conflicting results. The cognitive mechanism by which hosts recognize parasitic eggs may vary across brood parasite hosts, and this may explain variation in experimental outcome across studies investigating egg rejection in hosts of egg-mimicking brood parasites. In contrast, for hosts of non-egg-mimetic parasites, intraclutch egg color variation is not predicted to co-vary with foreign egg rejection, irrespective of cognitive mechanism. Here we tested for effects of intraclutch egg color variation in a host of nonmimetic brood parasite by manipulating egg color in American robins (Turdus migratorius), hosts of brown-headed cowbirds (Molothrus ater). We recorded robins' behavioral responses to simulated cowbird parasitism in nests where color variation was artificially enhanced or reduced. We also quantified egg color variation within and between unmanipulated robin clutches as perceived by robins themselves using spectrophotometric measures and avian visual modeling. In unmanipulated nests, egg color varied more between than within robin clutches. As predicted, however, manipulation of color variation did not affect rejection rates. Overall, our results best support the scenario wherein egg rejection is the outcome of selective pressure by a nonmimetic brood parasite, because robins are efficient rejecters of foreign eggs, irrespective of the color variation within their own clutch.

Experimental Shifts in Intraclutch Egg Color Variation Do Not Affect Egg Rejection in a Host of a Non-Egg-Mimetic Avian Brood Parasite

PubMed Central

Croston, Rebecca; Hauber, Mark E.

2015-01-01

Avian brood parasites lay their eggs in the nests of other birds, and impose the costs associated with rearing parasitic young onto these hosts. Many hosts of brood parasites defend against parasitism by removing foreign eggs from the nest. In systems where parasitic eggs mimic host eggs in coloration and patterning, extensive intraclutch variation in egg appearances may impair the host’s ability to recognize and reject parasitic eggs, but experimental investigation of this effect has produced conflicting results. The cognitive mechanism by which hosts recognize parasitic eggs may vary across brood parasite hosts, and this may explain variation in experimental outcome across studies investigating egg rejection in hosts of egg-mimicking brood parasites. In contrast, for hosts of non-egg-mimetic parasites, intraclutch egg color variation is not predicted to co-vary with foreign egg rejection, irrespective of cognitive mechanism. Here we tested for effects of intraclutch egg color variation in a host of nonmimetic brood parasite by manipulating egg color in American robins (Turdus migratorius), hosts of brown-headed cowbirds (Molothrus ater). We recorded robins’ behavioral responses to simulated cowbird parasitism in nests where color variation was artificially enhanced or reduced. We also quantified egg color variation within and between unmanipulated robin clutches as perceived by robins themselves using spectrophotometric measures and avian visual modeling. In unmanipulated nests, egg color varied more between than within robin clutches. As predicted, however, manipulation of color variation did not affect rejection rates. Overall, our results best support the scenario wherein egg rejection is the outcome of selective pressure by a nonmimetic brood parasite, because robins are efficient rejecters of foreign eggs, irrespective of the color variation within their own clutch. PMID:25831051

Mercury alters initiation and construction of nests by zebra finches, but not incubation or provisioning behaviors.

PubMed

Chin, Stephanie Y; Hopkins, William A; Cristol, Daniel A

2017-11-01

Mercury is an environmental contaminant that impairs avian reproduction, but the behavioral and physiological mechanisms underlying this effect are poorly understood. The objective of this study was to determine whether lifetime dietary exposure to mercury (1.2 µg/g wet weight in food) impacted avian parental behaviors, and how this might influence reproductive success. To distinguish between the direct effects of mercury on parents and offspring, we created four treatment groups of captive-bred zebra finches (Taeniopygia guttata), with control and mercury-exposed adults raising cross-fostered control or mercury-exposed eggs (from maternal transfer). Control parents were 23% more likely to fledge young than parents exposed to mercury, regardless of egg exposure. Mercury-exposed parents were less likely to initiate nests than controls and spent less time constructing them. Nests of mercury-exposed pairs were lighter, possibly due to an impaired ability to bring nest material into the nestbox. However, nest temperature, incubation behavior, and provisioning rate did not differ between parental treatments. Unexposed control eggs tended to have shorter incubation periods and higher hatching success than mercury-exposed eggs, but there was no effect of parental exposure on these parameters. We accidentally discovered that parent finches transfer some of their body burden of mercury to nestlings during feeding through secretion in the crop. These results suggest that, in mercury-exposed songbirds, pre-laying parental behaviors, combined with direct exposure of embryos to mercury, likely contribute to reduced reproductive success and should be considered in future studies. Further research is warranted in field settings, where parents are exposed to greater environmental challenges and subtle behavioral differences might have more serious consequences than were observed in captivity.

Fulicin regulates the female reproductive organs of the snail, Achatina fulica.

PubMed

Fujisawa, Y; Masuda, K; Minakata, H

2000-08-01

Fulicin is a D-amino acid-containing neuropeptide that has been thought to control male copulatory behavior in the land snail, Achatina fulica. In the present study, we demonstrated that the vagina and the oviduct of Achatina were densely innervated by fulicin-like immunoreactive neuronal fibers. We confirmed that fulicin was actually present in the vagina by mass spectrometry. Furthermore, fulicin showed a profound excitatory effect on contractions of the vagina and the oviduct. These results suggest that fulicin controls female egg-laying behavior as an excitatory neuropeptide regulating the female reproductive organs of the snail.

Effects of comb dubbing on the performance of laying stocks.

PubMed

Fairfull, R W; Crober, D C; Gowe, R S

1985-03-01

Three studies were conducted with birds dubbed at hatch vs. dubbed and dewattled at 118 days or 255 to 260 days of age or with normal hens. In the first, involving 5928 pullets of four strains housed 1 per cage, dubbing and dewattling at 255 to 260 days caused small adverse effects on egg numbers as compared with nondubbed controls. Body size was reduced, and both egg weight (EW) and shell strength were increased slightly. In the second study, involving 8180 pullets of nine strains housed 1 per cage, dubbing and dewattling at 118 days slightly increased survivor egg production (SEP) and laying house mortality, and reduced age at first egg, 240-day EW, and 450-day Haugh units (HU), as compared with dubbing only at hatch. There were significant strain by dubbing treatment interactions for hen-day rate of lay (HDR) and SEP. In the third study, involving 1824 pullets of three strain crosses housed 2 and 3 birds per cage (three different cage sizes), there were no significant differences between birds dubbed at hatch and those not dubbed. Variation in age at 50% production, SEP, and HDR was reduced for the dubbed groups. These studies show that the older the birds are when dubbed, the greater the negative effects of dubbing. Hens dubbed at hatch exhibit no effects with the early dubbing or adverse effects in the laying house.

Transfer of pyrrolizidine alkaloids from various herbs to eggs and meat in laying hens.

PubMed

Mulder, Patrick P J; de Witte, Susannah L; Stoopen, Geert M; van der Meulen, Jan; van Wikselaar, Piet G; Gruys, Erik; Groot, Maria J; Hoogenboom, Ron L A P

2016-12-01

To investigate the potential transfer of pyrrolizidine alkaloids (PAs), laying hens were fed for 14 days with diets containing 0.5% of dried common ragwort, common groundsel, narrow-leaved ragwort or viper's bugloss, or 0.1% of common heliotrope. This resulted in total PA levels in feed of respectively 5.5, 11.1, 53.1, 5.9 and 21.7 mg kg - 1 , with varying composition. PAs were transferred to eggs, in particular yolk, with steady-state levels of respectively 12, 21, 216, 2 and 36 µg kg - 1 . Overall transfer rates for the sum of PAs were estimated between 0.02% and 0.23%, depending on the type of PAs in the feed. In animals slaughtered shortly after the last exposure, levels in meat were slightly lower than those in eggs, levels in livers somewhat higher. When switched to clean feed, levels in eggs gradually decreased, but after 14 days were still above detection limits in the hens exposed to higher PA levels. Similar was the case for meat and especially kidneys and livers. It is concluded that the intake of PA containing herbs by laying hens may result in levels in eggs and meat that could be of concern for consumers, and as such should be avoided.

Brazil nut meal and spray-dried egg powders as alternatives to synthetic methionine in organic laying hen diets.

PubMed

Burley, H K; Patterson, P H

2017-09-01

The United States organic poultry industry is currently facing a limitation on dietary inclusion of synthetic methionine (Met). This study investigated Brazil nut protein powder (BNPP), spray-dried egg white (SDEW), and spray-dried egg blend (70:30 albumen: yolk) (SDEB) as alternatives to synthetic Met in organic laying hen diets. A total of 270 Hy-Line Brown laying hens was fed 5 diets from 22 to 38 wk of age, with 6 replicates of 3 adjacent cages per diet and 3 hens per cage. Diets included a commercial control (COM) (non-organic with standard CP and synthetic Met), an organic control (ORG) (with no synthetic Met, but higher CP to meet Met requirements), and 3 organic treatment diets with no synthetic Met, but including BNPP, SDEW, or SDEB at levels to meet Met requirements. Egg production and quality, body weight (BW), feed intake, and manure nutrients and ammonia were assessed. Data were analyzed using the PROC MIXED procedure of SAS, with Tukey's test used for multiple mean comparisons, and P ≤ 0.05 was deemed statistically significant. Body weight was greatest for the COM diet, and feed conversion improved for hens fed egg-based diets compared to controls. Egg weight and production did not differ between COM and treatment diets. The SDEW diet had greater albumen height and Haugh units compared to ORG and BNPP diets and greater percent albumen compared to COM and BNPP diets. Specific gravity was greatest for BNPP fed hens. Manure DM and potash were highest from COM and BNPP diets, respectively. Both egg-based diets increased ammonia flux relative to the COM diet. The BNPP and egg-based diets were lower in cost for $/metric tonne, $/dozen eggs, and $/kg of eggs compared to the ORG diet. The ingredients assessed herein could, therefore, cost-effectively replace synthetic Met in organic hen diets without negatively impacting egg production. © 2017 Poultry Science Association Inc.

Performance, egg quality, and blood plasma chemistry of laying hens fed hempseed and hempseed oil.

PubMed

Neijat, M; Gakhar, N; Neufeld, J; House, J D

2014-11-01

The aim of this study was to compare the performance of hens (feed intake, rate of lay, egg weight, and BW gain), egg quality and blood biochemistry (enzymes, electrolytes, proteins, and other plasma constituents) of laying hens fed diets containing hemp products. Forty-eight Lohmann LSL-Classic (white-egg layers; 19 wk of age) were individually caged and fed 1 of 6 wheat-barley-soybean-based diets for a period of 12 wk. The diets consisted of hempseed (HS; 10, 20, or 30%), hempseed oil (HO; 4.5 or 9.0%), or a control diet (corn oil-based). All diets were formulated to contain similar levels of crude fat (11%), energy (2,800 kcal/kg), and CP (17%). Data were analyzed as a completely randomized design using the repeated measure analysis of the PROC MIXED procedure of SAS. The results indicated that the inclusion of up to 30 and 9.0% HS and HO, respectively, to diets of laying hens had no significant effects on hen performance, egg quality, or plasma level of metabolites (proteins, glucose, uric acid, and cholesterol) and electrolytes (Na, K, Cl, P, and Ca). Overall plasma enzyme concentrations, particularly gamma-glutamyl transferase, were significantly (P < 0.01) lowest at the 10 and 20% levels of HS inclusion, or at the 4.5% HO level of inclusion of the hempseed products compared with the higher levels or control fed hens. Similar effects were also observed for plasma aspartate aminotransferase levels but with the HS enriched diets only (P < 0.05), particularly being lowest at the inclusion levels of 10 and 20% HS compared with the control. The results may imply a possible protective effect of HS- and HO-containing diets, particularly at 10% HS, 20% HS, and 4.5% HO levels, on liver damage/injury. In summary, both HO and HS appear to be well tolerated by laying hens as judged by markers of plasma clinical chemistry supporting the safety and efficacy of hemp products for use in laying hen rations. ©2014 Poultry Science Association Inc.

An insect with selective control of egg coloration.

PubMed

Abram, Paul K; Guerra-Grenier, Eric; Després-Einspenner, Marie-Lyne; Ito, Shosuke; Wakamatsu, Kazumasa; Boivin, Guy; Brodeur, Jacques

2015-08-03

The color and patterning of animal eggs has important consequences for offspring survival. There are examples of between-species and polymorphic differences in egg coloration in birds and amphibians [1-3], as well as cases of birds and insects whose nutritional status or age can cause within-individual variation in egg pigmentation [4-6]. However, no studies to date have demonstrated that individual animals can selectively control the color of their eggs. Here, we show that individual females of the predatory stink bug Podisus maculiventris can control the pigmentation of their eggs during oviposition, as a response to environmental conditions. The color of egg masses produced by individual females can range from pale yellow to dark black/brown. Females tend to lay darker eggs, which are more resistant to UV radiation, on the upper surface of leaves where UV exposure is highest in nature. Conversely, they lay lighter eggs on the undersides of leaves. However, egg color is not determined by the intensity of UV radiation falling on the surface where they are laid. Rather, female stink bugs appear to use a visual assessment of oviposition substrate reflectance to determine egg color. Unexpectedly, biochemical analyses revealed that the egg pigment is not melanin, the most ubiquitous light-absorbing pigment in animals. Our study offers the first example of an animal able to selectively control the color of its eggs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Worker reproduction of the invasive yellow crazy ant Anoplolepis gracilipes.

PubMed

Lee, Ching-Chen; Nakao, Hirotaka; Tseng, Shu-Ping; Hsu, Hung-Wei; Lin, Gwo-Li; Tay, Jia-Wei; Billen, Johan; Ito, Fuminori; Lee, Chow-Yang; Lin, Chung-Chi; Yang, Chin-Cheng Scotty

2017-01-01

Reproductive division of labor is one of the key features of social insects. Queens are adapted for reproduction while workers are adapted for foraging and colony maintenance. In many species, however, workers retain functional ovaries and can lay unfertilized male eggs or trophic eggs. Here we report for the first time on the occurrence of physogastric workers and apparent worker reproduction in the invasive yellow crazy ant Anoplolepis gracilipes (Fr. Smith). We further examined the reproductive potential and nutritional role of physogastric workers through multidisciplinary approaches including morphological characterization, laboratory manipulation, genetic analysis and behavioral observation. Egg production with two types of eggs, namely reproductive and trophic eggs, by physogastric workers was found. The reproductive egg was confirmed to be haploid and male-destined, suggesting that the workers produced males via arrhenotokous parthenogenesis as no spermatheca was discovered. Detailed observations suggested that larvae were mainly fed with trophic eggs. Along with consumption of trophic eggs by queens and other castes as part of their diet, the vital role of physogastric workers as "trophic specialist" is confirmed. We propose that adaptive advantages derived from worker reproduction for A. gracilipes may include 1) trophic eggs provisioned by physogastric workers likely assist colonies of A. gracilipes in overcoming unfavorable conditions such as paucity of food during critical founding stage; 2) worker-produced males are fertile and thus might offer an inclusive fitness advantage for the doomed orphaned colony.

nfi-1 affects behavior and life-span in C. elegans but is not essential for DNA replication or survival

PubMed Central

Lazakovitch, Elena; Kalb, John M; Matsumoto, Reiko; Hirono, Keiko; Kohara, Yuji; Gronostajski, Richard M

2005-01-01

Background The Nuclear Factor I (one) (NFI) family of transcription/replication factors plays essential roles in mammalian gene expression and development and in adenovirus DNA replication. Because of its role in viral DNA replication NFI has long been suspected to function in host DNA synthesis. Determining the requirement for NFI proteins in mammalian DNA replication is complicated by the presence of 4 NFI genes in mice and humans. Loss of individual NFI genes in mice cause defects in brain, lung and tooth development, but the presence of 4 homologous NFI genes raises the issue of redundant roles for NFI genes in DNA replication. No NFI genes are present in bacteria, fungi or plants. However single NFI genes are present in several simple animals including Drosophila and C. elegans, making it possible to test for a requirement for NFI in multicellular eukaryotic DNA replication and development. Here we assess the functions of the single nfi-1 gene in C. elegans. Results C. elegans NFI protein (CeNFI) binds specifically to the same NFI-binding site recognized by vertebrate NFIs. nfi-1 encodes alternatively-spliced, maternally-inherited transcripts that are expressed at the single cell stage, during embryogenesis, and in adult muscles, neurons and gut cells. Worms lacking nfi-1 survive but have defects in movement, pharyngeal pumping and egg-laying and have a reduced life-span. Expression of the muscle gene Ce titin is decreased in nfi-1 mutant worms. Conclusion NFI gene function is not needed for survival in C. elegans and thus NFI is likely not essential for DNA replication in multi-cellular eukaryotes. The multiple defects in motility, egg-laying, pharyngeal pumping, and reduced lifespan indicate that NFI is important for these processes. Reduction in Ce titin expression could affect muscle function in multiple tissues. The phenotype of nfi-1 null worms indicates that NFI functions in multiple developmental and behavioral systems in C. elegans, likely regulating genes that function in motility, egg-laying, pharyngeal pumping and lifespan maintenance. PMID:16242019

Validation of an UHPLC-MS/MS Method for Screening of Antimicrobial Residues in Eggs and Their Application to Analyses of Eggs from Laying Hens Subjected to Pharmacological Treatment

PubMed Central

Caldeira, Letícia Gomes Magnago; Santos, Flávio Alves; de Oliveira, Andréa Melo Garcia; Lima, Josefa Abucater; de Souza, Leonardo Francisco; da Silva, Guilherme Resende; de Assis, Débora Cristina Sampaio

2017-01-01

A multiresidue method by UHPLC/MS-MS was optimized and validated for the screening and semiquantitative detection of antimicrobials residues from tetracyclines, aminoglycosides, quinolones, lincosamides, β-lactams, sulfonamides, and macrolides families in eggs. A qualitative approach was used to ensure adequate sensitivity to detect residues at the level of interest, defined as maximum residue limit (MRL), or less. The applicability of the methods was assessed by analyzing egg samples from hens that had been subjected to pharmacological treatment with neomycin, enrofloxacin, lincomycin, oxytetracycline, and doxycycline during five days and after discontinuation of medication (10 days). The method was adequate for screening all studied analytes in eggs, since the performance parameters ensured a false-compliant rate below or equal to 5%, except for flumequine. In the analyses of eggs from laying hens subjected to pharmacological treatment, all antimicrobial residues were detected throughout the experimental period, even after discontinuation of medication, except for neomycin, demonstrating the applicability of the method for analyses of antimicrobial residues in eggs. PMID:29181222

Effect of an artificial Ascaridia galli infection on egg production, immune response, and liver lipid reserve of free-range laying hens.

PubMed

Sharma, N; Hunt, P W; Hine, B C; McNally, J; Sharma, N K; Iqbal, Z; Normant, C; Andronicos, N M; Swick, R A; Ruhnke, I

2018-02-01

This study was conducted to determine the effect of Ascaridia galli infection on free-range laying hens. Lohmann Brown laying hens (n = 200) at 17 wk of age were allocated to 4 treatment groups (n = 50 per group), each with 5 replicate pens of 10 hens. Hens in 3 treatment groups were orally inoculated with different doses of embryonated A. galli eggs: low (250 eggs), medium (1,000 eggs), and high (2,500 eggs) levels, whereas hens of the control group were not infected. Infection levels were monitored using excreta egg counts and mature A. galli worm counts in the intestine. Anti A. galli antibody titers (IgY) in the serum were measured prior to infection, and at 6, 11, 15, and 20 wk post infection (PI) and in egg yolk at 11 and 20 wk PI. Parameters evaluated included feed intake, egg production, egg weight, egg mass, FCR, liver weight, liver fat, and intra epithelial immune cell infiltration. The results showed no difference in feed intake, body weight, or FCR among any treatment groups (P > 0.05). Egg production was lower in the low infection group compared to other groups at 20 wk of age (P < 0.01). Serum IgY was higher in the infected groups' hens at 20 wk PI compared to control group hens (P < 0.01). Yolk IgY increased significantly over time and was higher in infected hens compared to hens of the control group at 11 and 20 wk PI (P < 0.001). No differences were observed in liver lipid content or intraepithelial lymphocytes infiltration among treatment groups. Ascaridia galli eggs in the coprodeum content and adult A. galli worm count were higher in infected hens compared to hens of the control group (P < 0.01). In conclusion, the effects of artificial infection with A. galli on the parameters investigated were minor, and egg yolk antibody may be a more reliable indicator of A. galli infection than serum antibody or excreta egg count. © 2017 Poultry Science Association Inc.

Productive performance and blood profiles of laying hens fed Hermetia illucens larvae meal as total replacement of soybean meal from 24 to 45 weeks of age.

PubMed

Marono, S; Loponte, R; Lombardi, P; Vassalotti, G; Pero, M E; Russo, F; Gasco, L; Parisi, G; Piccolo, G; Nizza, S; Di Meo, C; Attia, Y A; Bovera, F

2017-06-01

The aim of the research was to study the effects of an insect meal from Hermetia illucens larvae (HILM) as complete replacement of soybean meal (SBM) on productive performance and blood profiles of laying hens, from 24 to 45 wk of age. A total of 108 24-week-old Lohmann Brown Classic laying hens was equally divided into 2 groups (54 hens/group, 9 replicates of 6 hens/group). From 24 to 45 wk of age, the groups were fed 2 different isoproteic and isoenergetic diets: the control group (SBM) was fed a corn-soybean meal based diet, while in the HILM group the soybean meal was completely replaced by Hermetia illucens larvae meal. Feed intake, number of eggs produced, and egg weight were recorded weekly along the trial. At 45 wk of age, blood samples were collected from 2 hens per replicate. The use of HIML led to a more favorable (P < 0.01) feed conversion ratio in hens but lay percentage, feed intake, average egg weight, and egg mass were higher (P < 0.01) in hens fed the SBM diet. Hens fed insect meal produced a higher percentage of eggs from small (S), medium (M), and extra-large (XL) classes (P < 0.01) than SBM, while the SBM group had a higher percentage of eggs from the large (L) class (P < 0.01). The levels of globulin and albumin to globulin ratio were, respectively, higher and lower (P < 0.05) in HILM than the SBM group. Cholesterol and triglycerides were higher (P < 0.05 and P < 0.01, respectively) in hens from SBM than in the HILM group. Blood levels of Ca were higher (P < 0.01) in hens fed insect meal, while creatinine was higher (P < 0.01) in blood of hens fed SBM. Hermetia illucens larvae meal can be a suitable alternative protein source for laying hens even if the complete replacement of soybean meal needs further investigation to avoid the negative effects on feed intake. © 2017 Poultry Science Association Inc.

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

Effects of zinc oxide nanoparticles on the egg quality, immune response, zinc retention, and blood parameters of laying hens in the late phase of production.

PubMed

Abedini, M; Shariatmadari, F; Karimi Torshizi, M A; Ahmadi, H

2018-06-01

The objective of this study was to evaluate the effects of dietary supplementation with zinc oxide nanoparticles (ZnO-NPs) on the performance, egg quality, Zn retention, immunity responses, superoxide dismutase activity (SOD), egg malondialdehyde (MDA) content, and serum parameters in laying hens in the late phase of production. A total of 288 laying hens at 64 weeks of age were randomly assigned to 4 treatments with 6 replicates, and 12 birds within each group. Experimental diets included a corn-soybean meal-based diet (without Zn supplementation) and a basal diet supplemented with 80 mg/kg of Zn-oxide, ZnO-NPs, and Zn-methionine. The results indicated that egg production and egg mass were significantly higher in the Zn-methionine and ZnO-NPs groups (p < .05). Also, eggshell thickness and shell strength increased in the ZnO-NPs group as compared with the other groups (p < .05). Moreover, Zn supplementation decreased egg loss (p < .05). There were significant differences among treatments in Zn deposition in tibiotarsus, liver, pancreas, eggs, and excreta (p < .01). Antibody titre, heterophil (%(, and phytohemagglutinin (PHA) were significantly higher in birds fed with Zn-supplemented diets (p < .05). In treatments supplemented with ZnO-NPs and Zn-methionine, the SOD activity in the liver, pancreas, and plasma was greater as compared with the other treatments (p < .05). The MDA content in eggs was significantly reduced in groups supplemented with Zn (p < .01). Moreover, dietary Zn supplementation significantly affected serum total protein, albumin, glucose, alkaline phosphatase activity, carbonic anhydrase activity, and Zn level (p < .05). In conclusion, this study demonstrated that dietary supplementation with ZnO-NPs can improve the performance of laying hens. Therefore, ZnO-NPs can enhance zinc absorption in the intestine of aged layers and can be a more suitable source of zinc than regular Zn-oxide in diets. © 2018 Blackwell Verlag GmbH.

Impact of supplementing diets with propolis on productive performance, egg quality traits and some haematological variables of laying hens.

PubMed

Abdel-Kareem, A A A; El-Sheikh, T M

2017-06-01

One hundred and twenty eight, 28-weeks-old Lohmann LSL hybrid layers were used in this experiment, which lasted 12 weeks to investigate the effect of propolis supplementation on the productive performance, egg quality traits and haematological variables of laying hens. All hens were randomly classified into four equal experimental groups, eight replicates (4 birds/each). Hens in group 1 were fed on a commercial diet and considered as control group, while those in groups 2, 3 and 4 were fed on the same commercial diet and supplemented with 250, 500 and 1000 mg propolis/kg diet. The obtained results revealed that daily feed consumption/hen increased insignificantly with increasing propolis level than that of the control group. Regarding the means of egg mass and egg production rate, it was observed that the laying hens fed diets containing 250 and 1000 mg propolis/kg significantly (p < 0.05) produced more and heaver egg in comparison with control group. External egg quality traits have not affected with increasing the level of propolis, while eggshell weight was significantly (p < 0.05) increased. The internal egg quality traits except albumen and yolk percentages increased significantly (p < 0.05) with increasing propolis level for treated hens as compared to those in the control. Concerning the haematological parameters, the results showed that the levels of total protein and globulin increased significantly with increasing propolis level, while cholesterol and liver enzymes were significantly decreased (p < 0.05). Heterophils count of hens in the treated groups significantly decreased, whereas the lymphocyte count significantly increased, resulting in a decreased H/L ratio than that of the control group. Thus, it could be concluded that the supplementation of 250 mg propolis/kg diet is highly recommended to improving egg production, blood constituent and haematological parameters of the commercial laying hens. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

Gravid Anopheles gambiae sensu stricto avoid ovipositing in Bermuda grass hay infusion and it's volatiles in two choice egg-count bioassays.

PubMed

Eneh, Lynda K; Okal, Michael N; Borg-Karlson, Anna-Karin; Fillinger, Ulrike; Lindh, Jenny M

2016-05-12

A number of mosquito species in the Culex and Aedes genera prefer to lay eggs in Bermuda grass (Cynodon dactylon) hay infusions compared to water alone. These mosquitoes are attracted to volatile compounds from the hay infusions making the infusions effective baits in gravid traps used for monitoring vectors of arboviral and filarial pathogens. Since Bermuda grass is abundant and widespread, it is plausible to explore infusions made from it as a potential low cost bait for outdoor monitoring of the elusive malaria vector Anopheles gambiae s.s. This study investigated preferential egg laying of individual An. gambiae s.s. in hay infusion or in tap water treated with volatiles detected in hay infusion headspace compared to tap water alone, using two-choice egg-count bioassays. Infusions were prepared by mixing 90 g of dried Bermuda grass (hay) with 24 L of unchlorinated tap water in a bucket, and leaving it for 3 days at ambient temperature and humidity. The volatiles in the headspace of the hay infusion were sampled with Tenax TA traps for 20 h and analysed using gas chromatography coupled to mass spectrometry. In total, 18 volatiles were detected in the infusion headspace. Nine of the detected compounds and nonanal were selected for bioassays. Eight of the selected compounds have previously been suggested to attract/stimulate egg laying in An. gambiae s.s. Gravid females were significantly (p < 0.05) less likely to lay eggs in hay infusion dilutions of 25, 50 and 100 % and in tap water containing any of six compounds (3-methylbutanol, phenol, 4-methylphenol, nonanal, indole, and 3-methylindole) compared to tap water alone. The oviposition response to 10 % hay infusion or any one of the remaining four volatiles (4-hepten-1-ol, phenylmethanol, 2-phenylethanol, or 4-ethylphenol) did not differ from that in tap water. Anopheles gambiae s.s. prefers to lay eggs in tap water rather than Bermuda grass hay infusion. This avoidance of the hay infusion appears to be mediated by volatile organic compounds from the infusion. It is, therefore, unlikely that Bermuda grass hay infusion as formulated and used in gravid traps for Culex and Aedes mosquitoes will be suitable baits for monitoring gravid An. gambiae s.s.

Do purely capital layers exist among flying birds? Evidence of exogenous contribution to arctic-nesting common eider eggs.

PubMed

Sénéchal, Edith; Bêty, Joël; Gilchrist, H Grant; Hobson, Keith A; Jamieson, Sarah E

2011-03-01

The strategy of relying extensively on stored resources for reproduction has been termed capital breeding and is in contrast to income breeding, where needs of reproduction are satisfied by exogenous (dietary) resources. Most species likely fall somewhere between these two extremes, and the position of an organism along this gradient can influence several key life-history traits. Common eiders (Somateria mollissima) are the only flying birds that are still typically considered pure capital breeders, suggesting that they depend exclusively on endogenous reserves to form their eggs and incubate. We investigated the annual and seasonal variation in contributions of endogenous and exogenous resources to egg formation in eiders breeding at the East Bay colony in the Canadian Arctic. We collected prey items along with females and their eggs during various stages of breeding and used two complementary analytical approaches: body reserve dynamics and stable isotope [δ(13)C, δ(15)N] mixing models. Indices of protein reserves remained stable from pre-laying to post-laying stages, while lipid reserves declined significantly during laying. Similarly, stable isotope analyses indicated that (1) exogenous nutrients derived from marine invertebrates strongly contributed to the formation of lipid-free egg constituents, and (2) yolk lipids were constituted mostly from endogenous lipids. We also found evidence of seasonal variation in the use of body reserves, with early breeders using proportionally more exogenous proteins to form each egg than late breeders. Based on these results, we reject the hypothesis that eiders are pure capital layers. In these flying birds, the fitness costs of a strict capital breeding strategy, such as temporary loss of flight capability and limitation of clutch and egg size, may outweigh benefits such as a reduction in egg predation rate.

Radiocesium patterns in wood duck eggs and nesting females in a contaminated reservoir

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

Colwell, S.V.; Kennamer, R.A.; Brisbin, I.L. Jr.

Radionuclide releases from nuclear industry are an important ecological issue, particularly because these contaminants may directly affect animals and may be transferred to the hunting public through consumption. During 1991-92, we collected 13 clutches of wood duck eggs from nest boxes established in an abandoned reactor cooling reservoir. We examined whole-egg radiocesium ({sup 137}Cs) levels and apportionment within egg components (albumen, yolk, and shell). Whole-egg concentrations averaged 0.113 Becquerel (Bq)/g wet mass (SE=0.01, n = 137) over 2 years. Albumen had the highest concentration of {sup 137}Cs (x = 1.096 Bq/g dry mass), followed by shell (x = 0.132 Bq/gmore » dry mass) and yolk (x = 0.098 Bq/g dry mass). Levels of potassium (K), a chemical analog of Cs, suggested that contamination levels in yolk were disproportionally lower than those in albumen. Levels of {sup 137}Cs that appeared in these components may reflect temporal differences in the sythesis of yolk and albumen. Laying order did not relate to whole-egg {sup 137}Cs concentrations within clutches, but {sup 137}Cs concentrations in post-laying females were positively related to mean egg {sup 137}Cs levels in their respective clutches (r{sup 2} = 0.97). While female ducks and their eggs examined in this study would not have posed a health hazard to persons consuming them as food, we suggested that {sup 137}Cs levels in breeding female wood ducks and their clutches may be indicators of foraging habitat selection (both contaminated and uncontaminated) during the laying cycle. 23 refs., 2 figs., 2 tabs.« less

Effect of light-emitting diode (LED) vs. fluorescent (FL) lighting on laying hens in aviary hen houses: Part 2 - Egg quality, shelf-life and lipid composition.

PubMed

Long, H; Zhao, Y; Xin, H; Hansen, H; Ning, Z; Wang, T

2016-01-01

In this 60-wk study, egg quality, egg shelf-life, egg cholesterol content, total yolk lipids, and yolk fatty acid composition of eggs produced by Dekalb white laying hens in commercial aviary houses with either light-emitting diode (LED) or fluorescent (FL) lighting were compared. All parameters were measured at 27, 40, and 60 wk of age, except for egg shelf-life, which was compared at 50 wk of age. The results showed that, compared to the FL regimen, the LED regimen resulted in higher egg weight, albumen height, and albumen weight at 27 wk of age, thicker shells at 40 wk of age, but lower egg weight at 60 wk of age. Egg quality change was similar between the lighting regimens during the 62-d egg storage study, indicating that LED lighting did not influence egg shelf-life. Eggs from both lighting regimens had similar cholesterol content. However, cholesterol concentration of the yolk (15.9 to 21.0 mg cholesterol/g wet weight yolk) observed in this study was higher than that of United States Department of Agriculture (USDA) database (10.85 mg/g). No significant differences in total lipids or fatty acid composition of the yolks were detected between the two lighting regimens. © 2015 Poultry Science Association Inc.

Mercury in the blood and eggs of American kestrels fed methylmercury chloride

USGS Publications Warehouse

French, J.B.; Bennett, R.S.; Rossmann, R.

2010-01-01

American kestrels (Falco sparverius) were fed diets containing methylmercury chloride (MeHg) at 0, 0.6, 1.7, 2.8, 3.9, or 5.0 ??g/g (dry wt) starting approximately eight weeks before the onset of egg laying. Dietary treatment was terminated after 12 to 14 weeks, and unhatched eggs were collected for Hg analysis. Blood samples were collected after four weeks of treatment and the termination of the study (i.e., 12-14 weeks of treatment). Clutch size decreased at dietary concentrations above 2.8 ??g/g. The average total mercury concentration in clutches of eggs and in the second egg laid (i.e., egg B) increased linearly with dietary concentration. Mercury concentrations in egg B were approximately 25% lower than in the first egg laid and similar in concentration to the third egg laid. Mercury concentrations in whole blood and plasma also increased linearly with dietary concentration. Total Hg concentrations in June blood samples were lower than those in April, despite 8 to 10 weeks of additional dietary exposure to MeHg in the diet. This is likely because of excretion of Hg into growing flight feathers beginning shortly after the start of egg production. The strongest relationships between Hg concentrations in blood and eggs occurred when we used blood samples collected in April before egg laying and feather molt. ?? 2010 SETAC.

Salmonella Enteritidis organ invasion and egg contamination in experimentally infected laying hens housed in conventional or enriched cages.

USDA-ARS?s Scientific Manuscript database

Both disease surveillance and epidemiologic analyses have confirmed a strong association between human salmonellosis and the prevalence of Salmonella Enteritidis (SE) in commercial egg flocks. The majority of human illnesses caused by this pathogen are attributed to contaminated eggs. Animal welfare...

Assessing tissue colonization and egg contamination by Salmonella Oranienburg in laying hens

USDA-ARS?s Scientific Manuscript database

Transmission of Salmonella into table eggs could be via trans-ovarian (vertical) or trans-shell (horizontal) routes. CDC reported a multi state outbreak in the Midwest (2016) from consumption of eggs contaminated with Salmonella Oranienburg (SO), and this strain was closely related genetically to a ...

Food responsiveness regulates episodic behavioral states in Caenorhabditis elegans

PubMed Central

McCloskey, Richard J.; Fouad, Anthony D.; Churgin, Matthew A.

2017-01-01

Animals optimize survival and reproduction in part through control of behavioral states, which depend on an organism’s internal and external environments. In the nematode Caenorhabditis elegans a variety of behavioral states have been described, including roaming, dwelling, quiescence, and episodic swimming. These states have been considered in isolation under varied experimental conditions, making it difficult to establish a unified picture of how they are regulated. Using long-term imaging, we examined C. elegans episodic behavioral states under varied mechanical and nutritional environments. We found that animals alternate between high-activity (active) and low-activity (sedentary) episodes in any mechanical environment, while the incidence of episodes and their behavioral composition depend on food levels. During active episodes, worms primarily roam, as characterized by continuous whole body movement. During sedentary episodes, animals exhibit dwelling (slower movements confined to the anterior half of the body) and quiescence (a complete lack of movement). Roaming, dwelling, and quiescent states are manifest not only through locomotory characteristics but also in pharyngeal pumping (feeding) and in egg-laying behaviors. Next, we analyzed the genetic basis of behavioral states. We found that modulation of behavioral states depends on neuropeptides and insulin-like signaling in the nervous system. Sensory neurons and the Foraging homolog EGL-4 regulate behavior through control of active/sedentary episodes. Optogenetic stimulation of dopaminergic and serotonergic neurons induced dwelling, implicating dopamine as a dwell-promoting neurotransmitter. Our findings provide a more unified description of behavioral states and suggest that perception of nutrition is a conserved mechanism for regulating animal behavior. NEW & NOTEWORTHY One strategy by which animals adapt to their internal states and external environments is by adopting behavioral states. The roundworm Caenorhabditis elegans is an attractive model for investigating how behavioral states are genetically and neuronally controlled. Here we describe the hierarchical organization of behavioral states characterized by locomotory activity, feeding, and egg-laying. We show that decisions to engage in these behaviors are controlled by the nervous system through insulin-like signaling and the perception of food. PMID:28228583

Eggshell bacterial levels of non-washed and washed eggs from caged and cage-free hens

USDA-ARS?s Scientific Manuscript database

The bacteria levels of non-washed and washed eggs obtained from caged and cage-free laying hens housed on either all shavings or all wire slat floors were determined. On eight sample days (from 22 to 52 weeks at 4 week intervals), 20 eggs were collected from each pen (n=120/sample day). Ten eggs p...

The effects of nanosilver on egg quality traits in laying Japanese quail

NASA Astrophysics Data System (ADS)

Farzinpour, Amjad; Karashi, Naser

2013-04-01

Silver nanoparticles could prove to be a valuable alternative raw material for antibiotics and disinfectants as it is relatively free of adverse effects. Nanosilver is now been put to practical use in commonly used items, such as, clothes, electric home appliances, and electronic industry, but has not been widely applied in the medical or pharmacological fields. This study was designed to investigate the effects of nanosilver on egg quality traits in laying Japanese quail in completely randomized design with four treatments and six repetitions at 0, 4, 8 and 12 ppm of silver nanoparticle levels. Eggs collected daily and egg parameters, including egg weight, length, width; yolk weight and eggshell thickness were examined. The effect of the different silver nanoparticle levels was determined using the General Linear Model of SAS procedure, whilst differences between the groups were determined using least significant difference test. Results indicated that silver nanoparticles at all levels caused significantly reduce of yolk weight and hen-day egg production for each week than the control treatment ( P < 0.05), whilst silver nanoparticle had no significant effect on egg weight, egg length and width and eggshell thickness.

Laying-sequence-specific variation in yolk oestrogen levels, and relationship to plasma oestrogen in female zebra finches (Taeniopygia guttata)

PubMed Central

Williams, Tony D.; Ames, Caroline E.; Kiparissis, Yiannis; Wynne-Edwards, Katherine E.

2005-01-01

We investigated the relationship between plasma and yolk oestrogens in laying female zebra finches (Taeniopygia guttata) by manipulating plasma oestradiol (E2) levels, via injection of oestradiol-17β, in a sequence-specific manner to maintain chronically high plasma levels for later-developing eggs (contrasting with the endogenous pattern of decreasing plasma E2 concentrations during laying). We report systematic variation in yolk oestrogen concentrations, in relation to laying sequence, similar to that widely reported for androgenic steroids. In sham-manipulated females, yolk E2 concentrations decreased with laying sequence. However, in E2-treated females plasma E2 levels were higher during the period of rapid yolk development of later-laid eggs, compared with control females. As a consequence, we reversed the laying-sequence-specific pattern of yolk E2: in E2-treated females, yolk E2 concentrations increased with laying-sequence. In general therefore, yolk E2 levels were a direct reflection of plasma E2 levels. However, in control females there was some inter-individual variability in the endogenous pattern of plasma E2 levels through the laying cycle which could generate variation in sequence-specific patterns of yolk hormone levels even if these primarily reflect circulating steroid levels. PMID:15695208

Factors that influence the onset of parental care in zebra finches: Roles for egg stimuli and prolactin.

PubMed

Smiley, Kristina O; Adkins-Regan, Elizabeth

2018-05-09

Parental care is a critical component for determining reproductive success both for a current set of offspring but also over the lifetime of the individual. The hormone prolactin has often been implicated as a parental care hormone across taxa but causal relationships have only been strongly demonstrated in mammals and few select species of birds. For instance, in mammals, maternal care towards foster pups can be induced by exogenous treatment with prolactin, in concert with other reproductive hormones involved in pregnancy. We aimed to address this causal mechanism in birds by artificially elevating prolactin during the nest building and egg laying stages using vasoactive intestinal peptide (VIP) and then exposing them to foster chicks. We predicted that increasing prolactin would increase brooding and feeding behaviors towards foster chicks compared to the saline control group. Parental behavior towards foster chicks was only shown by individuals who had initiated clutches regardless of treatment. VIP treatment had no effect on parental behavior; however, a positive relationship was found between male and female feeding rates in the VIP but not control group. Our results suggest that both eggs and chicks are sufficient to stimulate foster care, perhaps through endogenous prolactin signalling, while further elevations of prolactin may serve to synchronize parental behaviors between pairs. Copyright © 2018 Elsevier B.V. All rights reserved.

The toxic effects of combined aflatoxins and zearalenone in naturally contaminated diets on laying performance, egg quality and mycotoxins residues in eggs of layers and the protective effect of Bacillus subtilis biodegradation product.

PubMed

Jia, Ru; Ma, Qiugang; Fan, Yu; Ji, Cheng; Zhang, Jianyun; Liu, Tao; Zhao, Lihong

2016-04-01

The toxic effect of aflatoxins (AF) and zearalenone (ZEA) and their combination on laying performance, egg quality and toxins residues in eggs, as well as the efficacy of Bacillus subtilis biodegradation product (BDP) for ameliorating these effects in layers were evaluated. Layers were submitted to a two phase experiment. The first phase was an intoxication period (18-23 wk) with birds fed 7 (3 × 2 + 1) diets (3 treatments with mycotoxins: AF (123.0 μg/kg), ZEA (260.2 μg/kg), or AF + ZEA (123.0 + 260.2 μg/kg); 2 treatments with or without BDP (1000 g/t); and a control group contained no toxins nor BDP). The next phase was a recovery period (24-29 wk) in which birds were fed a toxin-free diet. In the intoxication period, AF and AF + ZEA groups exhibited lower egg production, feed intake and shell thickness, and higher AFB1, AFB2 and AFM1 residues as compared with the control group. In addition, AF and ZEA exerted synergistic effects on egg production and feed intake. Moreover, AF alone or combined with ZEA had a continuous toxic effect on laying performance in the recovery phase. Addition of BDP offset these negative effects, showing that BDP has a protective effect on layers fed contaminated diets. Copyright © 2016 Elsevier Ltd. All rights reserved.

The role of egg-nest contrast in the rejection of brood parasitic eggs.

PubMed

Aidala, Zachary; Croston, Rebecca; Schwartz, Jessica; Tong, Lainga; Hauber, Mark E

2015-04-15

Hosts of avian brood parasites can avoid the reproductive costs of raising genetically unrelated offspring by rejecting parasitic eggs. The perceptual cues and controls mediating parasitic egg discrimination and ejection are well studied: hosts are thought to use differences in egg color, brightness, maculation, size and shape to discriminate between their own and foreign eggs. Most theories of brood parasitism implicitly assume that the primary criteria to which hosts attend when discriminating eggs are differences between the eggs themselves. However, this assumption is confounded by the degree to which chromatic and achromatic characteristics of the nest lining co-vary with egg coloration, so that egg-nest contrast per se might be the recognition cue driving parasitic egg detection. Here, we systematically tested whether and how egg-nest contrast itself contributes to foreign egg discrimination. In an artificial parasitism experiment, we independently manipulated egg color and nest lining color of the egg-ejector American robin (Turdus migratorius), a host of the obligate brood parasitic brown-headed cowbird (Molothrus ater). We hypothesized that the degree of contrast between foreign eggs and the nest background would affect host egg rejection behavior. We predicted that experimentally decreasing egg-nest chromatic and achromatic contrast (i.e. rendering parasitic eggs more cryptic against the nest lining) would decrease rejection rates, while increasing egg-nest contrast would increase rejection rates. In contrast to our predictions, egg-nest contrast was not a significant predictor of egg ejection patterns. Instead, egg color significantly predicted responses to parasitism. We conclude that egg-egg differences are the primary drivers of egg rejection in this system. Future studies should test for the effects of egg-nest contrast per se in predicting parasitic egg recognition in other host-parasite systems, including those hosts building enclosed nests and those parasites laying cryptic eggs, as an alternative to hypothesized effects of egg-egg contrast. © 2015. Published by The Company of Biologists Ltd.

Effects of dietary supplementation of resveratrol on performance, egg quality, yolk cholesterol and antioxidant enzyme activity of laying hens.

PubMed

Feng, Z H; Gong, J G; Zhao, G X; Lin, X; Liu, Y C; Ma, K W

2017-10-01

1. This experiment was conducted to evaluate the effects of dietary supplementation of resveratrol on laying performance, egg quality, egg yolk cholesterol and antioxidant enzyme activities of laying hens. 2. A total of 360 Beijing PINK-1 laying hens (60 weeks old) were randomly distributed among five dietary treatments, each of which included 6 replicates of 12 hens. Dietary treatments were basal diet supplemented with 0 (control), 0.5, 1.0, 2.0 and 4.0 g/kg diet resveratrol. The study lasted for 9 weeks including 1 week of adaptation and 8 weeks of the main experimental period. 3. The results indicated that dietary resveratrol significantly improved feed conversion ratios during 5-8 weeks and 1-8 weeks of the trial. Increasing dietary concentrations of the resveratrol linearly improved Haugh unit and albumen height of eggs. 4. The content of total cholesterol (TC), total triglyceride (TG), low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C) in serum and cholesterol in yolk was significantly decreased by dietary resveratrol, and there were significant linear correlations between these indexes and resveratrol supplemental levels. 5. Dietary resveratrol supplementation significantly improved serum Glutathione peroxidase (GSH-Px) enzyme activity and decreased serum malondialdehyde (MDA) content in groups with 2.0 and 4.0 g/kg resveratrol as compared to the control, respectively. However, supplementation of resveratrol did not affect the activity of serum superoxide dismutase (SOD). 6. It is concluded that resveratrol supplementation has a positive effect on performance, lipid-related traits and antioxidant activity of laying hens.

Short-term effects of lower oil dried distillers grains with solubles in laying hen rations.

PubMed

Purdum, Sheila; Hanford, Kathy; Kreifels, Brett

2014-10-01

Extraction of oil from dried distillers grains has become a common practice among US ethanol producers. The valuable oil has been diverted to markets other than poultry feed, leaving new dried distillers grains with solubles (DDGS) products higher in fiber and purportedly lower in ME. This study compared 3 DDGS products with 10.3, 7.3, or 5.2% ether extract, respectively, with a corn-soy control ration in young Bovan laying hens for a feeding period from 20 to 33 wk of age. The DDGS was fed at the rate of 20% of the ration. Lower oil content of DDGS had no effect on short-term egg production parameters: feed intake, egg production, egg weight or mass, and hen weight gain. The diets containing lower fat DDGS (5.2%) did have reduced AME and kilocalories per day intake for laying hens. For each percent reduction in oil from a normal DDGS sample (10.3%) to medium oil (7.3%) DDGS, AME decreased 42.3 kcal/kg of diet. However, total kilocalories per day intake did sustain good egg production during this short trial. ©2014 Poultry Science Association Inc.

Prevention of egg contamination by Salmonella Enteritidis after oral vaccination of laying hens with Salmonella Enteritidis ΔtolC and ΔacrABacrEFmdtABC mutants.

PubMed

Kilroy, Sofie; Raspoet, Ruth; Haesebrouck, Freddy; Ducatelle, Richard; Van Immerseel, Filip

2016-08-12

Vaccination of laying hens has been successfully used to reduce egg contamination by Salmonella Enteritidis, decreasing human salmonellosis cases worldwide. Currently used vaccines for layers are either inactivated vaccines or live attenuated strains produced by mutagenesis. Targeted gene deletion mutants hold promise for future vaccines, because specific bacterial functions can be removed that may improve safety and allow differentiation from field strains. In this study, the efficacy of Salmonella Enteritidis ΔtolC and ΔacrABacrEFmdtABC strains in laying hens as live vaccines was evaluated. The mutants are deficient in either the membrane channel TolC (ΔtolC) or the multi-drug efflux systems acrAB, acrEF and mdtABC (ΔacrABacrEFmdtABC). These strains have a decreased ability for gut and tissue colonization and are unable to survive in egg white, the latter preventing transmission of the vaccine strains to humans. Two groups of 30 laying hens were orally inoculated at day 1, 6 weeks and 16 weeks of age with 10(8) cfu of either vaccine strain, while a third group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 5 × 10(7) cfu Salmonella Enteritidis PT4 S1400/94. The vaccine strains were not shed or detected in the gut, internal organs or eggs, 2 weeks after the third vaccination. The strains significantly protected against gut and internal organ colonization, and completely prevented egg contamination by Salmonella Enteritidis under the conditions of this study. This indicates that Salmonella Enteritidis ΔtolC and ΔacrABacrEFmdtABC strains might be valuable strains for vaccination of layers against Salmonella Enteritidis.

Cooler butterflies lay larger eggs: developmental plasticity versus acclimation.

PubMed Central

Fischer, Klaus; Eenhoorn, Evelien; Bot, Adriane N M; Brakefield, Paul M; Zwaan, Bas J

2003-01-01

We use a full factorial design to investigate the effects of maternal and paternal developmental temperature, as well as female oviposition temperature, on egg size in the butterfly Bicyclus anynana. Butterflies were raised at two different temperatures and mated in four possible sex-by-parental-temperature crosses. The mated females were randomly divided between high and low oviposition temperatures. On the first day after assigning the females to different temperatures, only female developmental temperature affected egg size. Females reared at the lower temperature laid larger eggs than those reared at a higher temperature. When eggs were measured again after an acclimation period of 10 days, egg size was principally determined by the prevailing temperature during oviposition, with females ovipositing at a lower temperature laying larger eggs. In contrast to widely used assumptions, the effects of developmental temperature were largely reversible. Male developmental temperature did not affect egg size in either of the measurements. Overall, developmental plasticity and acclimation in the adult stage resulted in very similar patterns of egg size plasticity. Consequently, we argue that the most important question when testing the significance of acclamatory changes is not at which stage a given plasticity is induced, but rather whether plastic responses to environmental change are adaptive or merely physiological constraints. PMID:14561294

Doxycycline depletion and residues in eggs after oral administration to laying hens.

PubMed

Gajda, Anna; Posyniak, Andrzej

2015-01-01

The depletion of doxycycline (DC) residues in eggs was determined after oral drug administration by drinking water to laying hens. The antibiotic was supplied to birds for 5 consecutive days and the eggs were collected during medication and 18 days after withdrawal. DC residues were determined by LC-MS/MS. DC was isolated from eggs with a solution of 0.02 M of oxalic acid (pH 4), 0.1 M Na2EDTA and acetonitrile. The limit of detection (LOD) and limit of quantification (LOQ) of the method were 2 and 5 µg kg(-1), respectively. Analyses were performed on whole egg, egg white and yolk separately. DC was detectable 24 h after the beginning of administration. The concentration of antibiotic increased daily, resulting in the highest DC concentration in whole eggs at the first day of the withdrawal period. Thirteen days after withdrawal, the content of DC in whole eggs was below the LOQ of the method. However, some differences were found in the depletion curve of DC between egg white and yolk. Residues of DC in egg white were much higher during treatment and 1 day after withdrawal, but later the concentration in egg white decreased fairly rapidly and a higher DC content in egg yolk was observed. The depletion period was shorter for egg white than for yolk, and DC was detected in the egg white until 12 days after withdrawal and 2 days more in egg yolk than in white. DC reached a peak faster in egg white, but the residues were detectable for longer period in the yolk.

The efficacy of using exogenous enzymes cocktail on production, egg quality, egg nutrients and blood metabolites of laying hens fed distiller's dried grains with solubles.

PubMed

Abd El-Hack, M E; Chaudhry, M T; Mahrose, K M; Noreldin, A; Emam, M; Alagawany, M

2018-04-01

An experiment was performed using 120 Hisex Brown laying hens for evaluating the effects of different inclusion levels of corn distiller's dried grains with solubles (DDGS) as a replacement of soybean meal (SBM) with or without enzyme cocktail on performance, egg quality, egg nutrients and blood metabolites in laying hens through 22-42 weeks of age. A 4 × 2 factorial design experiment was performed including four substitution levels of DDGS (0, 250, 500 and 750 g/kg respectively) and two enzyme cocktail levels (0 and 250 mg/kg diet). The used enzyme in this study "Gallazyme" composed of xylanase, Trichoderma longibrachiatum (600 units/g), protease, Bacillus subtilis (8,000 units/g) and amylase and Bacillus amyloliquofaciens (800 units/g). The control diet showed the best feed efficiency followed by the intermediate levels of DDGS. The lowest value of feed efficiency was found in the group fed the highest level of DDGS. Enzyme addition improved feed efficiency and decreased laying rate. Increasing DDGS levels was associated with albumin and shell thickness increases. Dietary DDGS depressed all egg components except the organic matter which maximised in enzyme-treated groups. Increasing DDGS level was accompanied by increase in yolk cholesterol and total lipids. No significant impacts were detected with enzymes supplementation on yolk lipids profile. Excepting serum calcium and phosphorous, all serum constituents increased with increasing level of DDGS. Using enzyme markedly depressed serum ammonia by 15.02% and increased calcium by 6.44% compared with enzyme-free diets. Interaction between DDGS and enzyme was significant on most of studied parameters. It could be concluded that using enzyme cocktail in DDGS-based diets may improve feed efficiency and egg quality, in addition to lowering blood ammonia and increasing blood calcium. It is recommended to substitute SBM by DDGS up to 500 g/kg diet. © 2017 Blackwell Verlag GmbH.

Absence of evidence or evidence of absence? A transfer and depletion study of Sudan I in eggs.

PubMed

Piątkowska, Marta; Jedziniak, Piotr; Olejnik, Małgorzata; Żmudzki, Jan; Posyniak, Andrzej

2018-01-15

Sudan I is a carcinogenic industrial azo-dye, forbidden for use in food. However, it has been detected in food on several occasions, such as in paprika, used in animal husbandry to enhance egg yolk colour. Therefore, an animal experiment was designed to simulate the transfer of Sudan I to eggs after its unintentional administration to laying hens. A group of laying hens (n=18) received feed contaminated with Sudan I at the raising concentrations: 0.45mg/kg, 4.97mg/kg and 42.1mg/kg. Residues of Sudan I were detected in egg yolks (0.29±0.03µg/kg, mean±SD) only after the administration of the feed contaminated with the dye at the highest concentration. The determined concentrations were much lower than expected based on the compound's lipophilicity. In conclusion, the transfer of Sudan I to eggs was limited and strongly dependent on its concentration in feed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Mismatching between nest volume and clutch volume reduces egg survival and fledgling success in black-tailed gulls

PubMed Central

Yoo, Jeong-Chil

2016-01-01

Abstract A longstanding suggestion posits that parents prefer to match nest volume and clutch size (clutch volume), but few studies have tested this in colonial seabirds that nest in the open. Here, we demonstrate the effects of nest–clutch volume matching on egg survival, hatching, and fledgling success in black-tailed gulls Larus crassirostris on Hongdo Island, Korea. We show that the volume mismatch, defined as the difference between nest volume and total egg volume (the sum of all eggs’ volume in the clutch), was positively related to egg and chick mortality caused by predation, but was not significantly related to hatching success incurred by insulation during the incubation period. Although nest volume was negatively related to laying date, we found that the mismatch was positively related to laying date. Our results support the claim that well-matched nest–clutch volume may contribute to survival of eggs and chicks, and ultimately breeding success. PMID:29491934

Seamount egg-laying grounds of the deep-water skate Bathyraja richardsoni.

PubMed

Henry, L-A; Stehmann, M F W; De Clippele, L; Findlay, H S; Golding, N; Roberts, J M

2016-08-01

Highly localized concentrations of elasmobranch egg capsules of the deep-water skate Bathyraja richardsoni were discovered during the first remotely operated vehicle (ROV) survey of the Hebrides Terrace Seamount in the Rockall Trough, north-east Atlantic Ocean. Conductivity-temperature-depth profiling indicated that the eggs were bathed in a specific environmental niche of well-oxygenated waters between 4·20 and 4·55° C, and salinity 34·95-35·06, on a coarse to fine-grained sandy seabed on the seamount's eastern flank, whereas a second type of egg capsule (possibly belonging to the skate Dipturus sp.) was recorded exclusively amongst the reef-building stony coral Solenosmilia variabilis. The depths of both egg-laying habitats (1489-1580 m) provide a de facto refuge from fisheries mortality for younger life stages of these skates. © 2016 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

Adult pollen diet essential for egg maturation by a solitary osmia bee

USDA-ARS?s Scientific Manuscript database

Reproduction is a nutritionally costly activity for many insects, as their eggs are rich in lipids and proteins. Non-social bees lay especially large eggs. Adult female bees visit flowers to collect pollen and nectar, or sometimes oils, to feed their progeny. For adult bees, benefits of pollen feedi...

Nutritional modulation of health, egg quality and environmental pollution of the layers.

PubMed

Wang, Jing; Yue, Hongyuan; Wu, Shugeng; Zhang, Haijun; Qi, Guanghai

2017-06-01

World egg production and consumption have been increasing for the past decades. Traditional strategies in poultry nutrition have made vital contributions to this great growth in quantity. However, current global issues should be considered in modern egg production such as growing populations and food security, food safety and quality, limited resources and environmental problems. The development of knowledge of poultry nutrition and modern biotechnology provides novel nutritional approaches to closely fit the requirement of pullets and laying hens, which will consequently decrease the nutrition excretion and maintain the lower cost of feed. Nutrition has also been widely accepted as a strategy to influence health and diseases of laying hens. The maintenance of good health is an important prerequisite for improving productivity and egg quality. In addition, there are many measures and strategies for minimizing the incidence of egg defects and providing a choice of lifestyle to enhance human health. This paper reviews current research progress on developing innovative technologies and strategies to maximize animal health and performance, improve the quality of egg products and minimize pollution caused by poultry production.

Reed Warbler Hosts Fine-Tune their Defenses to Track Three Decades of Cuckoo Decline

PubMed Central

Thorogood, Rose; Davies, Nicholas B

2013-01-01

Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat parasitism by common cuckoos (Cuculus canorus). During the past three decades cuckoos have declined markedly across England, reducing parasitism at our study site (Wicken Fen) from 24% of reed warbler nests in 1985 to 1% in 2012. Here we show with experiments that host mobbing and egg rejection defenses have tracked this decline in local parasitism risk: the proportion of reed warbler pairs mobbing adult cuckoos (assessed by responses to cuckoo mounts and models) has declined from 90% to 38%, and the proportion rejecting nonmimetic cuckoo eggs (assessed by responses to model eggs) has declined from 61% to 11%. This is despite no change in response to other nest enemies or mimetic model eggs. Individual variation in both defenses is predicted by parasitism risk during the host’s egg-laying period. Furthermore, the response of our study population to temporal variation in parasitism risk can also explain spatial variation in egg rejection behavior in other populations across Europe. We suggest that spatial and temporal variation in parasitism risk has led to the evolution of plasticity in reed warbler defenses. PMID:24299407

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.

The relationship between the numbers of Salmonella Enteritidis, Salmonella Heidelberg, or Salmonella Hadar colonizing reproductive tissues of experimentally infected laying hens and deposition inside eggs.

PubMed

Gast, Richard K; Guraya, Rupa; Guard, Jean; Holt, Peter S

2011-06-01

Contamination of eggs by Salmonella Enteritidis has been a prominent cause of human illness for several decades and is the focus of a recently implemented national regulatory plan for egg-producing flocks in the United States. Salmonella Heidelberg has also been identified as an egg-transmitted pathogen. The deposition of Salmonella strains inside eggs is a consequence of reproductive tract colonization in infected laying hens, but prior research has not determined the relationship between the numbers of Salmonella that colonize reproductive organs and the associated frequency of egg contamination. In the present study, groups of laying hens in two trials were experimentally infected with large oral doses of strains of Salmonella Enteritidis (phage type 13a), Salmonella Heidelberg, or Salmonella Hadar. Reproductive tissues of selected hens were cultured to detect and enumerate Salmonella at 5 days postinoculation, and the interior contents of eggs laid between 6 and 25 days postinoculation were tested for contamination. Significantly more internally contaminated eggs were laid by hens infected with Salmonella Enteritidis (3.58%) than with strains of either Salmonella Heidelberg (0.47%) or Salmonella Hadar (0%). However, no significant differences were observed between Salmonella strains in either isolation frequency or the number of colony-forming units (CFU) isolated from ovaries or oviducts. Salmonella isolation frequencies ranged from 20.8% to 41.7% for ovaries and from 8.3% to 33.3% for oviducts. Mean Salmonella colonization levels ranged from 0.10 to 0.51 log CFU/g for ovaries and from 0.25 to 0.46 log CFU/g for oviducts. Although parallel rank-orders were observed for Salmonella enumeration (in both ovaries and oviducts) and egg contamination frequency, a statistically significant relationship could not be established between these two parameters of infection.

Comparative Effect of Dietary Soybean Oil, Fish Oil, and Coconut Oil on Performance, Egg Quality and Some Blood Parameters in Laying Hens.

PubMed

Dong, X F; Liu, S; Tong, J M

2018-04-14

Two hundred and sixteen 28-wk-old Hy-line laying hens were randomly distributed to three dietary treatments and fed 1of 3 diets containing 8% soybean oil, fish oil, or coconut oil from 28 to 47 wk of age to investigate comparative effect of dietary soybean oil, fish oil, and coconut oil on the performance, egg quality and blood malondialdehyde (MDA), aspartate transaminase (AST) and uric acid (UA). Hens fed fish oil showed poor performance compared with soybean oil or coconut oil, and especially egg weight throughout the trial was significantly and consistently decreased (P < 0.05) due to dietary fish oil. Unexpectedly, shell reflectivity throughout the majority of the trial was consistently and significantly higher (P < 0.05) when hens fed fish oil than that when fed soybean oil or coconut oil. Dietary treatments affected (P < 0.05) shell shape at 4 of 8 time points tested. Average shell shape in fish oil treatment was higher (P < 0.05) than that of coconut oil group. Albumen height, Haugh unit and yolk color were influenced by dietary treatments only at 1 or 2 time points. However, average albumen height and Haugh unit in fish oil treatment were higher (P < 0.05) than that of soybean oil or coconut oil treatments and average yolk color in coconut oil treatment was higher (P < 0.05) than that of soybean oil group. Serum MDA, AST and UA concentrations were increased (P < 0.05) by fish oil during the majority of the first 2 mo of the trial. These data suggested that the inclusion of fish oil into feed may reduce the performance of laying hens, especially the egg weight, decrease the intensity of egg brown color and increase blood MDA, AST and UA levels compared with soybean oil or coconut oil. As a result, hens fed fish oil may lay smaller, longer and lighter-brown eggs whereas those fed coconut oil produce blunter and darker-brown eggs relative to soybean oil.

Effects of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens.

PubMed

Ding, Xuemei; Yu, Yang; Su, Zhuowei; Zhang, Keying

2017-06-01

The study was conducted to investigate the effect of essential oils on performance, egg quality, nutrient digestibility and yolk fatty acid profile in laying hens. A total of 960 Lohmann laying hens aged 53 weeks were enrolled, under 4 different treatment diets supplemented with 0, 50, 100 and 150 mg/kg essential oils (Enviva EO, Dupont Nutrition Biosciences ApS, Denmark), respectively. Each treatment was replicated 8 times with 30 birds each. Birds were fed dietary treatment diets for 12 weeks (54 to 65 weeks). For data recording and analysis, a 12-week period was divided into 3 periods of 4 weeks' duration each: period 1 (54 to 57 weeks), period 2 (58 to 61 weeks), and period 3 (62 to 65 weeks). For the diet supplemented with Enviva EO, hen-day egg production and the feed conversion ratio (FCR) were significantly improved ( P  < 0.05) at weeks 58 to 61, and the eggshell thickness was significantly increased ( P  < 0.05) at week 65. However, egg production, egg weight, feed intake, FCR and other egg quality parameters (albumen height, Haugh unit, egg yolk color and eggshell strength) were not affected by the dietary treatment. In addition, compared with the control diet, protein digestibility in the 100 mg/kg Enviva EO treatment group was significantly increased ( P  < 0.05), and fat digestibility in the 100 and 150 mg/kg Enviva EO treatment groups was significantly decreased ( P  < 0.05), but Enviva EO had no effect on energy apparent digestibility. Saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) gradually decreased and polyunsaturated fatty acid (PUFA) increased with Enviva EO supplementation, but the difference was not significant. The data suggested that the supplementation of essential oils (Enviva EO) in laying hen diet did not show a significant positive effect on performance and yolk fatty acid composition but it tended to increase eggshell thickness and protein digestibility, especially at the dose of 50 mg/kg.

Effect of hesperidin dietary supplementation on hen performance, egg quality and yolk oxidative stability.

PubMed

Goliomytis, M; Orfanou, H; Petrou, E; Charismiadou, M A; Simitzis, P E; Deligeorgis, S G

2014-02-01

1. The purpose of this study was to evaluate the effects of dietary supplementation with hesperidin (one or 3 g/kg of feed) for 31 d on the performance, egg quality and yolk oxidative stability of brown and white laying hens (26-wk old). 2. Supplementation with hesperidin did not affect egg production, egg weight and egg quality traits. 3. No hesperidin effect on yolk and plasma cholesterol was observed. A strain effect was found with lower total and per g yolk cholesterol of brown hens in comparison to the white ones. 4. Oxidative stability of egg yolk, expressed as ng MDA/g yolk, was significantly improved in the hesperidin groups even from the first week of supplementation. At the same time, a significant improvement in the oxidative stability of egg yolk due to the incorporation of hesperidin in hens' diet was observed after 30 and 90 d of storage at 20°C and 4°C, respectively. 5. No hesperidin by strain interaction was detected for any of the traits measured. 6. In conclusion, incorporation of hesperidin to laying hens' feed did not affect productive and egg qualitative traits. On the other hand, dietary hesperidin supplementation significantly improved oxidative stability of both fresh and stored eggs. Antioxidant properties of hesperidin seem to make it a promising natural agent for improving the shelf life of eggs.

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.

Intraspecific variation in reproductive traits of burrowing owls

USGS Publications Warehouse

Conway, Meaghan; Nadeau, Christopher P.; Conway, Courtney J.

2012-01-01

Reviews of hatching asynchrony in birds recommended more studies on intraspecific variation in the extent of hatching asynchrony. We examined intraspecific variation in clutch size, laying chronology, onset of incubation, incubation period, and hatching asynchrony in burrowing owls (Athene cunicularia) in the Imperial Valley of California. Mean clutch size was 7.4 eggs and owls averaged 0.5 eggs laid per day. Females varied considerably in laying interval and onset of incubation (range = 1st to 9th egg in the clutch). The mean incubation period was 21.9 days. Hatching interval also varied greatly among females (x = 0.8, range 0.1-2.0 days between successively hatched eggs). Past burrowing owl studies have largely overlooked the substantial intraspecific variation in these traits or have reported estimates that differ from ours. Future studies designed to identify the environmental factors that explain the large intraspecific variation in these traits will likely provide insights into the constraints on local abundance.

An elm EST database for identifying leaf beetle egg-induced defense genes

PubMed Central

2012-01-01

Background Plants can defend themselves against herbivorous insects prior to the onset of larval feeding by responding to the eggs laid on their leaves. In the European field elm (Ulmus minor), egg laying by the elm leaf beetle ( Xanthogaleruca luteola) activates the emission of volatiles that attract specialised egg parasitoids, which in turn kill the eggs. Little is known about the transcriptional changes that insect eggs trigger in plants and how such indirect defense mechanisms are orchestrated in the context of other biological processes. Results Here we present the first large scale study of egg-induced changes in the transcriptional profile of a tree. Five cDNA libraries were generated from leaves of (i) untreated control elms, and elms treated with (ii) egg laying and feeding by elm leaf beetles, (iii) feeding, (iv) artificial transfer of egg clutches, and (v) methyl jasmonate. A total of 361,196 ESTs expressed sequence tags (ESTs) were identified which clustered into 52,823 unique transcripts (Unitrans) and were stored in a database with a public web interface. Among the analyzed Unitrans, 73% could be annotated by homology to known genes in the UniProt (Plant) database, particularly to those from Vitis, Ricinus, Populus and Arabidopsis. Comparative in silico analysis among the different treatments revealed differences in Gene Ontology term abundances. Defense- and stress-related gene transcripts were present in high abundance in leaves after herbivore egg laying, but transcripts involved in photosynthesis showed decreased abundance. Many pathogen-related genes and genes involved in phytohormone signaling were expressed, indicative of jasmonic acid biosynthesis and activation of jasmonic acid responsive genes. Cross-comparisons between different libraries based on expression profiles allowed the identification of genes with a potential relevance in egg-induced defenses, as well as other biological processes, including signal transduction, transport and primary metabolism. Conclusion Here we present a dataset for a large-scale study of the mechanisms of plant defense against insect eggs in a co-evolved, natural ecological plant–insect system. The EST database analysis provided here is a first step in elucidating the transcriptional responses of elm to elm leaf beetle infestation, and adds further to our knowledge on insect egg-induced transcriptomic changes in plants. The sequences identified in our comparative analysis give many hints about novel defense mechanisms directed towards eggs. PMID:22702658

An elm EST database for identifying leaf beetle egg-induced defense genes.

PubMed

Büchel, Kerstin; McDowell, Eric; Nelson, Will; Descour, Anne; Gershenzon, Jonathan; Hilker, Monika; Soderlund, Carol; Gang, David R; Fenning, Trevor; Meiners, Torsten

2012-06-15

Plants can defend themselves against herbivorous insects prior to the onset of larval feeding by responding to the eggs laid on their leaves. In the European field elm (Ulmus minor), egg laying by the elm leaf beetle ( Xanthogaleruca luteola) activates the emission of volatiles that attract specialised egg parasitoids, which in turn kill the eggs. Little is known about the transcriptional changes that insect eggs trigger in plants and how such indirect defense mechanisms are orchestrated in the context of other biological processes. Here we present the first large scale study of egg-induced changes in the transcriptional profile of a tree. Five cDNA libraries were generated from leaves of (i) untreated control elms, and elms treated with (ii) egg laying and feeding by elm leaf beetles, (iii) feeding, (iv) artificial transfer of egg clutches, and (v) methyl jasmonate. A total of 361,196 ESTs expressed sequence tags (ESTs) were identified which clustered into 52,823 unique transcripts (Unitrans) and were stored in a database with a public web interface. Among the analyzed Unitrans, 73% could be annotated by homology to known genes in the UniProt (Plant) database, particularly to those from Vitis, Ricinus, Populus and Arabidopsis. Comparative in silico analysis among the different treatments revealed differences in Gene Ontology term abundances. Defense- and stress-related gene transcripts were present in high abundance in leaves after herbivore egg laying, but transcripts involved in photosynthesis showed decreased abundance. Many pathogen-related genes and genes involved in phytohormone signaling were expressed, indicative of jasmonic acid biosynthesis and activation of jasmonic acid responsive genes. Cross-comparisons between different libraries based on expression profiles allowed the identification of genes with a potential relevance in egg-induced defenses, as well as other biological processes, including signal transduction, transport and primary metabolism. Here we present a dataset for a large-scale study of the mechanisms of plant defense against insect eggs in a co-evolved, natural ecological plant-insect system. The EST database analysis provided here is a first step in elucidating the transcriptional responses of elm to elm leaf beetle infestation, and adds further to our knowledge on insect egg-induced transcriptomic changes in plants. The sequences identified in our comparative analysis give many hints about novel defense mechanisms directed towards eggs.

Salmonella enterica serovar Enteridis (SE) infection in 5 commercial white egg and 3 commercial brown egg strains of laying hens: comparison of SE colonization with immune responsiveness

USDA-ARS?s Scientific Manuscript database

Different chicken breeds have been shown to exhibit varying susceptibility to infection with paratyphoid salmonellae. The current study was undertaken to compare the course of infection with SE in crops and intestines of 5 commercial white egg strains (W1-W5) and 3 commercial brown egg strains (B1-...

Comparing in vitro lymphocyte reactivity to Salmonella enterica serovar Enteridis (SE) antigens 5 commercial white egg and 3 commercial brown egg strains of laying hens following SE infection.

USDA-ARS?s Scientific Manuscript database

Different chicken breeds have been shown to exhibit varying susceptibility to infection with paratyphoid salmonellae. The current study was undertaken to compare the course of infection with SE in crops and intestines of 5 commercial white egg strains (W1-W5) and 3 commercial brown egg strains (B1-...

The influence of different single dietary sources on moult induction in laying hens.

PubMed

Mansoori, Behzad; Modirsanei, Mehrdad; Farkhoy, Mohsen; Kiaei, Mohammad-Mehdi; Honarzad, Jila

2007-11-01

An investigation was carried out to assess the possibility of using single dietary sources as alternatives to feed deprivation for the induction of moult in commercial laying hens. The study involved six dietary groups of 29 laying hens: unmoulted, dried tomato pomace, alfalfa meal, rice bran, cumin seed meal and feed withdrawal. The birds received the above diets during the moulting period (11 days), and body weight loss and ovary weight regression were measured. Post-moult production parameters (number of eggs produced per hen per day, egg weight, shell weight, yolk colour and Haugh unit) were measured for 12 weeks. Results showed that all dietary sources were as effective as feed withdrawal in causing ovary weight regression in birds. Birds provided with tomato pomace or alfalfa showed lower weight losses than feed-deprived birds at the end of the moulting period. Hens moulted by tomato pomace or alfalfa exhibited post-moult levels of egg production over a 12 week period that were superior to those of hens moulted by feed withdrawal. Post-moult eggs laid by hens moulted by all dietary sources were of comparable quality to eggs from feed-deprived hens and superior to those from unmoulted hens. As fibrous feeds with low metabolisable energy and an appreciable amount of protein, dried tomato pomace and alfalfa meal may be fed to hens on an ad libitum basis for effective moult induction while reducing the stress of severe starvation and retaining comparable egg quality and production. Copyright © 2007 Society of Chemical Industry.

Frequency and duration of fecal shedding of Salmonella serovars Heidelberg and Typhimurium by experimentally infected laying hens housed in enriched colony cages at different stocking densities

USDA-ARS?s Scientific Manuscript database

Eggs contaminated with Salmonella Enteritidis are leading sources of human salmonellosis, but S. Heidelberg and S. Typhimurium are also egg-associated pathogens. The management practices and housing facilities characterizing different systems for housing commercial egg flocks can influence Salmonell...

Effects of white phosphorus on mallard reproduction

USGS Publications Warehouse

Vann, S.I.; Sparling, D.W.; Ottinger, M.A.

2000-01-01

Extensive waterfowl mortality involving thousands of ducks, geese, and swans has occurred annually at Eagle River Flats, Alaska since at least 1982. The primary agent for this mortality has been identified as white phosphorus. Although acute and subacute lethality have been described, sublethal effects are less well known. This study reports on the effects of white phosphorus on reproductive function in the mallard (Anas platyrhynchos) in captivity. Fertility, hatching success, teratogenicity, and egg laying frequency were examined in 70 adult female mallards who received up to 7 daily doses of 0, 0.5, 1.0, and 2.0 mg/kg of white phosphorus. Measurements of fertility and hatchability were reduced by the white phosphorus. Teratogenic effects were observed in embryos from hens dosed at all treatment levels. Egg laying frequency was reduced even at the lowest treatment level; treated hens required a greater number of days to lay a clutch of 12 eggs than control hens. After two doses at 2.0 mg/kg, all females stopped laying completely for a minimum of 10 days and laying frequency was depressed for at least 45 days. Fertility of 10 adult male mallards dosed with 1.0 mg/kg of white phosphorus did not differ from 10 controls, but plasma testosterone levels were significantly (p < 0.05) reduced in the treated males 1 day after dosing ended. These results provide evidence that productivity of free-ranging mallards may be impaired if they are exposed to white phosphorus at typical field levels.

The Caenorhabditis elegans interneuron ALA is (also) a high-threshold mechanosensor

PubMed Central

2013-01-01

Background To survive dynamic environments, it is essential for all animals to appropriately modulate their behavior in response to various stimulus intensities. For instance, the nematode Caenorhabditis elegans suppresses the rate of egg-laying in response to intense mechanical stimuli, in a manner dependent on the mechanosensory neurons FLP and PVD. We have found that the unilaterally placed single interneuron ALA acted as a high-threshold mechanosensor, and that it was required for this protective behavioral response. Results ALA was required for the inhibition of egg-laying in response to a strong (picking-like) mechanical stimulus, characteristic of routine handling of the animals. Moreover, ALA did not respond physiologically to less intense touch stimuli, but exhibited distinct physiological responses to anterior and posterior picking-like touch, suggesting that it could distinguish between spatially separated stimuli. These responses required neither neurotransmitter nor neuropeptide release from potential upstream neurons. In contrast, the long, bilaterally symmetric processes of ALA itself were required for producing its physiological responses; when they were severed, responses to stimuli administered between the cut and the cell body were unaffected, while responses to stimuli administered posterior to the cut were abolished. Conclusion C. elegans neurons are typically classified into three major groups: sensory neurons with specialized sensory dendrites, interneurons, and motoneurons with neuromuscular junctions. Our findings suggest that ALA can autonomously sense intense touch and is thus a dual-function neuron, i.e., an interneuron as well as a novel high-threshold mechanosensor. PMID:24341457

The Caenorhabditis elegans interneuron ALA is (also) a high-threshold mechanosensor.

PubMed

Sanders, Jarred; Nagy, Stanislav; Fetterman, Graham; Wright, Charles; Treinin, Millet; Biron, David

2013-12-17

To survive dynamic environments, it is essential for all animals to appropriately modulate their behavior in response to various stimulus intensities. For instance, the nematode Caenorhabditis elegans suppresses the rate of egg-laying in response to intense mechanical stimuli, in a manner dependent on the mechanosensory neurons FLP and PVD. We have found that the unilaterally placed single interneuron ALA acted as a high-threshold mechanosensor, and that it was required for this protective behavioral response. ALA was required for the inhibition of egg-laying in response to a strong (picking-like) mechanical stimulus, characteristic of routine handling of the animals. Moreover, ALA did not respond physiologically to less intense touch stimuli, but exhibited distinct physiological responses to anterior and posterior picking-like touch, suggesting that it could distinguish between spatially separated stimuli. These responses required neither neurotransmitter nor neuropeptide release from potential upstream neurons. In contrast, the long, bilaterally symmetric processes of ALA itself were required for producing its physiological responses; when they were severed, responses to stimuli administered between the cut and the cell body were unaffected, while responses to stimuli administered posterior to the cut were abolished. C. elegans neurons are typically classified into three major groups: sensory neurons with specialized sensory dendrites, interneurons, and motoneurons with neuromuscular junctions. Our findings suggest that ALA can autonomously sense intense touch and is thus a dual-function neuron, i.e., an interneuron as well as a novel high-threshold mechanosensor.

Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata)

NASA Astrophysics Data System (ADS)

Gilbert, Lucy; Rutstein, Alison N.; Hazon, Neil; Graves, Jefferson A.

2005-04-01

The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

Oviposition by Female Plodia interpunctella (Lepidoptera: Pyralidae): Description and Time Budget Analysis of Behaviors in Laboratory Studies.

PubMed

Sambaraju, Kishan R; Donelson, Sarah L; Bozic, Janko; Phillips, Thomas W

2016-01-22

The oviposition behavior of the Indian meal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), a major insect pest of durable stored foods, was studied in small experimental arenas under laboratory conditions using videography, and a time budget analysis of its behaviors was documented. Resting gravid females typically became active shortly after the start of the scotophase. The characteristic behaviors exhibited by mated females prior to oviposition included antennal movement, grooming of antennae and mouth parts using the forelegs, walking or flying, and abdomen bending and dragging. Pre-oviposition behaviors such as antennal grooming and walking or flying were observed to alternate several times before females commenced the abdominal dragging behavior that preceded egg laying. Eggs were laid singly or sometimes in groups, either freely or stuck to food material. Gravid females showed little or no movement during the photophase; however, they actively flew and oviposited during the scotophase. Females allocated only a small portion of their time to oviposition while the rest of the time was spent away from food. Females oviposited on food material by making repeated visits, predominantly during the first four hours of the scotophase. Visits and time spent on food declined as the scotophase advanced.

Oviposition by Female Plodia interpunctella (Lepidoptera: Pyralidae): Description and Time Budget Analysis of Behaviors in Laboratory Studies

PubMed Central

Sambaraju, Kishan R.; Donelson, Sarah L.; Bozic, Janko; Phillips, Thomas W.

2016-01-01

The oviposition behavior of the Indian meal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), a major insect pest of durable stored foods, was studied in small experimental arenas under laboratory conditions using videography, and a time budget analysis of its behaviors was documented. Resting gravid females typically became active shortly after the start of the scotophase. The characteristic behaviors exhibited by mated females prior to oviposition included antennal movement, grooming of antennae and mouth parts using the forelegs, walking or flying, and abdomen bending and dragging. Pre-oviposition behaviors such as antennal grooming and walking or flying were observed to alternate several times before females commenced the abdominal dragging behavior that preceded egg laying. Eggs were laid singly or sometimes in groups, either freely or stuck to food material. Gravid females showed little or no movement during the photophase; however, they actively flew and oviposited during the scotophase. Females allocated only a small portion of their time to oviposition while the rest of the time was spent away from food. Females oviposited on food material by making repeated visits, predominantly during the first four hours of the scotophase. Visits and time spent on food declined as the scotophase advanced. PMID:26805893

Effects of live and killed vaccines against Mycoplasma gallisepticum on the performance characteristics of commercial layer chickens.

PubMed

Jacob, R; Branton, S L; Evans, J D; Leigh, S A; Peebles, E D

2014-06-01

Different vaccine strains of Mycoplasma gallisepticum have been used on multiple-age commercial layer farms in an effort to protect birds against virulent field-strain infections. Use of the F-strain of M. gallisepticum (FMG), as an overlay vaccine during lay, may be necessary because of the lower level of protection afforded by M. gallisepticum vaccines of low virulence given before lay. Two replicate trials were conducted to investigate effects of live and killed M. gallisepticum vaccines administered individually and in combination before lay, in conjunction with an FMG vaccine overlay after peak egg production (EP), on the performance characteristics of commercial layers. The following treatments were utilized at 10 wk of age (woa): 1) control (no vaccinations); 2) ts11 strain M. gallisepticum (ts11MG) vaccine; 3) M. gallisepticum-Bacterin vaccine (MG-Bacterin); and 4) ts11MG and MG-Bacterin vaccines combination. At 45 woa, half of the birds were overlaid with an FMG vaccine. Hen mortality, BW, egg weight, percentage hen-day EP, egg blood spots, and egg meat spots were determined at various time periods between 18 and 52 woa. The data from each trial were pooled. Treatment did not affect performance in interval I (23 to 45 woa). However, during interval II (46 to 52 woa), the EP of control and MG-Bacterin-vaccinated birds that later received an FMG vaccine overlay was lower than that in the other treatment groups. Furthermore, treatment application reduced bird BW during interval II. Despite the effects on BW and EP, no differences were observed for egg blood or meat spots among the various treatments. It is suggested that the vaccination of commercial layers before lay with ts11MG, but not MG-Bacterin, may reduce the negative impacts of an FMG overlay vaccination given during lay. These results establish that the vaccination of pullets with ts11MG in combination with the vaccination of hens with an FMG overlay, for continual protection against field-strain M. gallisepticum infections, may be used without suppressing performance. Poultry Science Association Inc.

[Food value of spiruline algae for the laying hen].

PubMed

Blum, J C; Guillaumin, S; Calet, C

1975-01-01

The three diets (composition in table I) were isonitrogenous (16,4 p. 100 crude protein), similar in their content of lysine and sulfur amino acids, but with different levels of spiruline algae : 0 (control); 7.5 or 15 p. 100. Each diet was used for the feeding of 48 hybrid pullets of medium size during a 24-week test period (32 to 56 weeks). Egg production (table II) was slightly better (47.1 g/hen/day) with 7.5 p. 100 of spirulines, compared to the control (45.3 g/hen/day), the difference being significant (P less than 0.01). With 15 p. 100 of spirulines egg production was similar to that observed in the control, but the average egg weight was reduced (58.5 vs 60.5 g) as a result of a lower albumen content. The colour of the egg yolk (table IV) was very light in the controls, but was a deep orange (above the maximum in the Roch scale) with 7.5 or 15 p. 100 of spirulines in the laying hen diet. The diet consumption, feed conversion and live weight variations (table III) show that the energy level is no higher in laying hens (about 2 500 kcal M.E./kg spirulines) than in the broiler.

Effects of Deinococcus spp. supplement on egg quality traits in laying hens.

PubMed

Li, I-Chen; Wu, Szu-Yin; Liou, Jenn-Fa; Liu, Hsiao-Hui; Chen, Jiau-Hua; Chen, Chin-Chu

2018-01-01

To counter the ill effects of synthetic dyes, bacterial pigment production as an alternative is now one of the promising and emerging fields of research. This study was conducted to evaluate the applicability of Deinococcus genus on the egg quality traits in laying hens. In study I, 24 single comb White Leghorn layers were fed with various 1 wt % Deinococcus bacterial strains for 10 d. In study II, 84 brown Hendrix layers were fed with one of 4 diets containing 0, 0.2, 1, or 5 wt % Deinococcus sp. GKB-Aid 1995 powder for 12 wk. In study III, 60 White Leghorn laying hens were fed either with or without 1 wt % Deinococcus sp. GKB-Aid 1995 powder, 1 wt % Deinococcus sp. GKB-Aid 1995 granules, or 1 wt % Deinococcus sp. GKB-Aid 1995 oily granules for 10 successive d. In all of the experiments, feeding Deinococcus powder did not affect egg quality traits except for the yolk color. In particular, supplementation with all Deinococcus powder treatments changed the yolk color (P < 0.05) in study I, with the best pigmentation score obtained by D. grandis and Deinococcus sp. GKB-Aid 1995. Moreover, longer supplementation of Deinococcus sp. GKB-Aid 1995 in study II had a significant effect on feed conversion ratio. With these findings under consideration, the present study suggests that the Deinococcus species, especially Deinococcus sp. GKB-Aid 1995, can be an excellent candidate for improving egg yolk color in laying hens. © 2017 Poultry Science Association Inc.

Effect of Dietary Supplementation of Red Ginseng By-product on Laying Performance, Blood Biochemistry, Serum Immunoglobulin and Microbial Population in Laying Hens.

PubMed

Kang, H K; Park, S-B; Kim, C H

2016-10-01

This study was carried out to investigate the effect of dietary supplementation of red ginseng by-product (RGB) on the laying performance, blood biochemistry, and microbial population in laying hens. A total of 120 Hy-Line Brown laying hens (75 weeks old) were randomly allotted to 1 of 3 dietary treatments with 4 replicates per treatment. A commercial-type basal diet was prepared, and 2 additional diets were prepared by supplementing 5.0 or 10.0 g/kg of RGB to the basal diet at the expense of corn. The diets were fed to hens on an ad libitum basis for 4 weeks. There were no differences in feed intake, egg weight, and feed conversion ratio during 4 weeks of the feeding trial. However, hen-day egg production was significantly greater (p<0.05) for the RGB treatment groups than that for the basal treatment group. There were no differences in triglyceride, aspartate aminotransferase, and alanine aminotransferase during the 4-week feeding trial. However, RGB supplementation increased (p<0.05) the serum immunoglobulin G (IgG) and IgM content compared with basal treatment group. The total cholesterol was lower (p<0.05) in the RGB treatments groups than that in the basal treatment group. The intestinal Lactobacillus population was greater (p<0.05) for the RGB treatments groups than that for the basal treatment group. However, the numbers of Salmonella and Escherichia coli were not different among dietary treatments. During the entire experiment, there was no significant difference in egg quality among all the treatments. In conclusion, in addition to improving hen-day production, there were positive effects of dietary RGB supplementation on serum immunoglobulin and cholesterol levels in laying hens.

Effect of Dietary Supplementation of Red Ginseng By-product on Laying Performance, Blood Biochemistry, Serum Immunoglobulin and Microbial Population in Laying Hens

PubMed Central

Kang, H. K.; Park, S.-B.; Kim, C. H.

2016-01-01

This study was carried out to investigate the effect of dietary supplementation of red ginseng by-product (RGB) on the laying performance, blood biochemistry, and microbial population in laying hens. A total of 120 Hy-Line Brown laying hens (75 weeks old) were randomly allotted to 1 of 3 dietary treatments with 4 replicates per treatment. A commercial-type basal diet was prepared, and 2 additional diets were prepared by supplementing 5.0 or 10.0 g/kg of RGB to the basal diet at the expense of corn. The diets were fed to hens on an ad libitum basis for 4 weeks. There were no differences in feed intake, egg weight, and feed conversion ratio during 4 weeks of the feeding trial. However, hen-day egg production was significantly greater (p<0.05) for the RGB treatment groups than that for the basal treatment group. There were no differences in triglyceride, aspartate aminotransferase, and alanine aminotransferase during the 4-week feeding trial. However, RGB supplementation increased (p<0.05) the serum immunoglobulin G (IgG) and IgM content compared with basal treatment group. The total cholesterol was lower (p<0.05) in the RGB treatments groups than that in the basal treatment group. The intestinal Lactobacillus population was greater (p<0.05) for the RGB treatments groups than that for the basal treatment group. However, the numbers of Salmonella and Escherichia coli were not different among dietary treatments. During the entire experiment, there was no significant difference in egg quality among all the treatments. In conclusion, in addition to improving hen-day production, there were positive effects of dietary RGB supplementation on serum immunoglobulin and cholesterol levels in laying hens. PMID:26954140

Effects of chronic and repeated repeated coritcosterone administration in rearing chickens on physiology, the onset of lay and egg production in hens.

USDA-ARS?s Scientific Manuscript database

A corticosterone (CORT) model was used to study the effects of repeated stress during rearing phase on physiology and performance of hens’ in subsequent laying period. Two hundred and seventy Hy-line laying birds were reared in environmentally controlled battery cages. At 7, 11, and 15 wk of age bir...

Failed landings after laying hen flight in a commercial aviary over two flock cycles.

PubMed

Campbell, D L M; Goodwin, S L; Makagon, M M; Swanson, J C; Siegford, J M

2016-01-01

Many egg producers are adopting alternative housing systems such as aviaries that provide hens a tiered cage and a litter-covered open floor area. This larger, more complex environment permits expression of behaviors not seen in space-limited cages, such as flight. Flight is an exercise important for strengthening bones; but domestic hens might display imperfect flight landings due to poor flight control. To assess the potential implications of open space, we evaluated the landing success of Lohmann white laying hens in a commercial aviary. Video recordings of hens were taken from 4 aviary sections at peak lay, mid lay and end lay across two flock cycles. Observations were made in each focal section of all flights throughout the day noting flight origin and landing location (outer perch or litter) and landing success or failure. In Flock 1, 9.1% of all flights failed and 21% failed in Flock 2. The number of flights decreased across the laying cycle for both flocks. Proportionally more failed landings were observed in the double row sections in Flock 2. Collisions with other hens were more common than slipping on the ground or colliding with aviary structures across sections and flocks. More hens slipped on the ground and collided with physical structures at peak lay for Flock 2 than at other time points. More collisions with other hens were seen at mid and end lay than at peak lay for Flock 2. Landings ending on perches failed more often than landings on litter. These results indicate potential for flight-related hen injuries in aviary systems resulting from failed landings, which may have implications for hen welfare and optimal system design and management.

Assessment of the efficacy of a topical combination of fipronil-permethrin (Frontline Tri-Act®/Frontect®) against egg laying and adult emergence of the cat flea (Ctenocephalides felis) in dogs

PubMed Central

Beugnet, Frédéric; Halos, Lénaïg; Lebon, Wilfried; Liebenberg, Julian

2016-01-01

This study was conducted to assess the prevention of egg laying and the inhibition of the emergence of the cat flea (Ctenocephalides felis) resulting from the application of a combination of fipronil and permethrin (Frontline Tri-Act®/Frontect®, Merial) on dogs. Sixteen healthy dogs were included after pre-treatment live flea counts and randomly allocated to two groups. Eight dogs served as untreated controls and 8 dogs were treated on Day 0 and Day 30 with topical application of fipronil/permethrin at the minimum dose of 6.76 mg/kg fipronil and 50.48 mg/kg permethrin. On days −2, 7, 21, 28, 42 and 56, each dog was infested with 100 fleas. Flea eggs were collected from each dog in individual trays from 12 to 36 h after treatment or each flea re-infestation. All fleas were removed by combing and counted 36 h after treatment or infestations. The collected eggs were counted and incubated for 28 days for larval development and adult emergence assessment. The curative efficacy of Frontline Tri-Act®/Frontect® against adult fleas 36 h after treatment was 95.3% and the efficacy remained 100% after subsequent flea infestations for 8 weeks. Compared to the control group, the treatment reduced egg laying by 84.5% within 36 h after first treatment and was 99.9%, 100%, 100%, 100%, 100% on collection days 7, 21, 29, 43 and 57, respectively. Frontline Tri-Act®/Frontect® reduced by 28.7% the emergence of new adult fleas from eggs laid during the 48 h of pre-treatment infestation. The inhibition of adult emergence from incubated flea eggs could not be assessed after flea re-infestation in the treated group as no eggs were collected. PMID:27991415

Single and combined effects of zinc and cinnamon essential oil in diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition

NASA Astrophysics Data System (ADS)

Torki, Mehran; Akbari, Mohsen; Kaviani, Keyomars

2015-09-01

This study was conducted to evaluate the effects of adding zinc (Zn), cinnamon essential oil (Ci), or their combination in diet on productive performance, egg quality, and blood parameters of laying hens reared under cold stress condition (8.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-Lite laying hens. Significant interactions between Ci and Zn on FCR, EW, EP, or EM were observed ( P < 0.05). The EP, EM, and EW increased, whereas FCR decreased ( P < 0.05) in the hens fed the diets including Ci and Zn (as single or combined form) compared to those fed the basal diet. There were significant interactions between Ci and Zn on the serum level of glucose and triglycerides as well as plasma concentration of zinc ( P < 0.05), so that serum content of glucose and triglyceride decreased and the plasma content of zinc increased in the hens fed the diets including Ci and Zn (together) compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by the combined form of Ci and Zn could have beneficial effects on performance and blood parameters of hens reared under cold stress condition.

Single and combined effects of zinc and cinnamon essential oil in diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition.

PubMed

Torki, Mehran; Akbari, Mohsen; Kaviani, Keyomars

2015-09-01

This study was conducted to evaluate the effects of adding zinc (Zn), cinnamon essential oil (Ci), or their combination in diet on productive performance, egg quality, and blood parameters of laying hens reared under cold stress condition (8.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-Lite laying hens. Significant interactions between Ci and Zn on FCR, EW, EP, or EM were observed (P < 0.05). The EP, EM, and EW increased, whereas FCR decreased (P < 0.05) in the hens fed the diets including Ci and Zn (as single or combined form) compared to those fed the basal diet. There were significant interactions between Ci and Zn on the serum level of glucose and triglycerides as well as plasma concentration of zinc (P < 0.05), so that serum content of glucose and triglyceride decreased and the plasma content of zinc increased in the hens fed the diets including Ci and Zn (together) compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by the combined form of Ci and Zn could have beneficial effects on performance and blood parameters of hens reared under cold stress condition.

In vivo and in vitro evaluation of tissue colonization and survival capacity of Salmonella Oranienburg in laying hens.

PubMed

Babu, Uma S; Proszkowiec-Weglarz, Monika; Sharma, Girdhari M; Pereira, Marion; Balan, Kannan V

2018-05-18

Salmonella enterica serovar Oranienburg (SO) was linked to a human salmonellosis outbreak in the Midwest in 2015 and 2016 from consumption of eggs. However, unlike Salmonella enterica serovar Enteritidis (SE), little is known regarding the potential of SO to colonize in laying hens and contaminate eggs. We used in vivo and in vitro models to evaluate tissue colonization and survival capacity of SO. Twenty eight-week-old laying hens were each challenged with an oral dose of approximately 107 (n = 92) or 109 (n = 96) colony-forming units (CFU) in 1 mL saline and evaluated after 1, 2, and 4 wk. Standard microbiological methods with pre-enrichment and enrichment in selective media were used for detection of SO in tissues, egg shell wash, internal egg contents, and excreta. Peak colonization of spleen (86.9%), ovaries (31.6%), upper oviduct (15.8%), and lower oviduct (34.3%) was detected between 1 and 2 wk post-infection (pi), while at 4 wk SO was only recovered from spleens (25%). Salmonella enterica serovar Oranienburg was not recovered from internal egg contents. However, the presence of SO on egg shells was seen when there were traces of excreta. Shedding in excreta was found in 92 and 100% birds gavaged with 107 and 109 CFU at 2 wk pi, respectively. The invasion and proliferation of SO in ovarian granulosa cells (GC) was compared to that of SE, and while the invasion of SO into GC was comparable to SE, proliferation of SO was significantly lower (P < 0.05). The infective potential of SO was also assessed by enumerating survival in egg white over 4 wk under refrigerated conditions, resulting in 65% survival at 4 wk. Overall, our data suggested that SO infection in layers did not result in egg contamination via vertical transmission, and colonization of egg-forming tissues was limited to 2 wk pi. Survival within GC and egg white demonstrates the ability of SO to withstand antibacterial factors and the potential of SO to penetrate the yolk.

Predicting mercury concentrations in mallard eggs from mercury in the diet or blood of adult females and from duckling down feathers

USGS Publications Warehouse

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

2010-01-01

Measurements of Hg concentrations in avian eggs can be used to predict possible harm to reproduction, but it is not always possible to sample eggs. When eggs cannot be sampled, some substitute tissue, such as female blood, the diet of the breeding female, or down feathers of hatchlings, must be used. When female mallards (Anas platyrhynchos) were fed diets containing methylmercury chloride, the concentration of Hg in a sample of their blood was closely correlated with the concentration of Hg in the egg they laid the day they were bled (r2=0.88; p<0.001). Even when the blood sample was taken more than two weeks after an egg was laid, there was a strong correlation between Hg concentrations in female blood and eggs (r2=0.67; p<0.0002). When we plotted the dietary concentrations of Hg we fed to the egg-laying females against the concentrations of Hg in their eggs, the r2 value was 0.96 (p<0.0001). When the concentrations of Hg in the down feathers of newly hatched ducklings were plotted against Hg in the whole ducklings, the r 2 value was 0.99 ( p<0.0003). Although measuring Hg in eggs may be the most direct way of predicting possible embryotoxicity, our findings demonstrate that measuring Hg in the diet of breeding birds, in the blood of egg-laying females, or in down feathers of hatchlings all can be used to estimate what concentration of Hg may have been in the egg.

HPLC residues of enrofloxacin and ciprofloxacin in eggs of laying hens.

PubMed

Gorla, N; Chiostri, E; Ugnia, L; Weyers, A; Giacomelli, N; Davicino, R; García Ovando, H

1997-05-01

Eggs of 12 laying hens with 5 mg/kg/day oral administration of 5% enrofloxacin (EFX) or ciprofloxacin (CFX) solution during 5 days contained residues from 0.02 to 1.98 microg/g (EFX) or 0.14 to 0.28 microg/g (CFX). At identical dosage regime High Performance Liquid Chromatograhy (HPLC) residues of EFX were 6-fold greater than CFX ones. Maximun concentrations were detected at the second day after the administration withdrawal. The limits of detection were 0.019 microg/g for EFX and 0.156 microg/g for CFX. The recovery was 36-50% for CFX and 49-85% for EFX. The withdrawal treatment periods in hens are six days for EFX and five days for CFX in order to avoid violative levels of egg residues.

Transfer of Maternal Antibodies against Avian Influenza Virus in Mallards (Anas platyrhynchos)

PubMed Central

van Dijk, Jacintha G. B.; Mateman, A. Christa; Klaassen, Marcel

2014-01-01

Maternal antibodies protect chicks from infection with pathogens early in life and may impact pathogen dynamics due to the alteration of the proportion of susceptible individuals in a population. We investigated the transfer of maternal antibodies against avian influenza virus (AIV) in a key AIV host species, the mallard (Anas platyrhynchos). Combining observations in both the field and in mallards kept in captivity, we connected maternal AIV antibody concentrations in eggs to (i) female body condition, (ii) female AIV antibody concentration, (iii) egg laying order, (iv) egg size and (v) embryo sex. We applied maternity analysis to the eggs collected in the field to account for intraspecific nest parasitism, which is reportedly high in Anseriformes, detecting parasitic eggs in one out of eight clutches. AIV antibody prevalence in free-living and captive females was respectively 48% and 56%, with 43% and 24% of the eggs receiving these antibodies maternally. In both field and captive study, maternal AIV antibody concentrations in egg yolk correlated positively with circulating AIV antibody concentrations in females. In the captive study, yolk AIV antibody concentrations correlated positively with egg laying order. Female body mass and egg size from the field and captive study, and embryos sex from the field study were not associated with maternal AIV antibody concentrations in eggs. Our study indicates that maternal AIV antibody transfer may potentially play an important role in shaping AIV infection dynamics in mallards. PMID:25386907

Effects of low dietary levels of methyl mercury on mallard reproduction

USGS Publications Warehouse

Heinz, G.

1974-01-01

Mallard ducks were fed a control diet or a diet containing 0.5 ppm or 3 ppm mercury (as methylmercury dicyandiamide). Health of adults and reproductive success were studied. The dietary level of 3 ppm mercury had harmful effects on reproduction, although it did not appear to affect the health of the adults during the 12 months of dosage. Ducks that were fed the diet containing 0.5 ppm mercury reproduced as well as controls, and ducklings from parents fed 0.5 ppm mercury grew faster in the first week of life than did controls....The greatest harm to reproduction associated with the diet containing 3 ppm mercury was an increase in duckling mortality, but reduced egg laying and increased embryonic mortality also occurred....During the peak of egg laying, eggs laid by controls tended to be heavier than eggs laid by ducks fed either level of mercury; however, there seemed to be no eggshell thinning associated with mercury treatment. Levels of mercury reached about 1 ppm in eggs from ducks fed a dietary dosage of 0.5 ppm mercury and between 6 and 9 ppm in the eggs from ducks fed 3 ppm mercury.

Effects of egg size, parental quality and hatch-date on growth and survival of Common Tern Sterna hirundo chicks

USGS Publications Warehouse

Arnold, J.M.; Hatch, J.J.; Nisbet, I.C.T.

2006-01-01

We examined the relative contributions of egg size, parental quality and hatch-date to growth and survival of second-hatched chicks (those chicks making the greatest contribution to differences in productivity among pairs) by exchanging clutches among nests of Common Terns Sterna hirundo matched for lay-date (range 13 May to 9 June). The mass of a second-laid egg in an exchanged clutch ranged from 17.70 to 23.80 g. Growth and survival were studied during three periods: early (days 0-3), middle (days 3-12) and late (days 12-25). Both egg mass and hatch-date were important predictors of hatchling mass (positive relationships), although there was no seasonal trend in egg mass. During the middle period, hatch-date was a significant predictor of mass gain and survival (inverse relationships). After controlling for hatch-date, other indices of parental quality made only small contributions to chick mass gain and survival. Our results suggest that although breeding early generally leads to greater overall survival of chicks, several important interactions among egg 'quality', parental quality and early laying may affect breeding success under specific conditions. ?? 2006 British Ornithologists' Union.

Maternally derived carotenoid pigments affect offspring survival, sex ratio, and sexual attractiveness in a colorful songbird

NASA Astrophysics Data System (ADS)

McGraw, K. J.; Adkins-Regan, E.; Parker, R. S.

2005-08-01

In egg-laying animals, mothers can influence the development of their offspring via the suite of biochemicals they incorporate into the nourishing yolk (e.g. lipids, hormones). However, the long-lasting fitness consequences of this early nutritional environment have often proved elusive. Here, we show that the colorful carotenoid pigments that female zebra finches ( Taeniopygia guttata) deposit into egg yolks influence embryonic and nestling survival, the sex ratio of fledged offspring, and the eventual ornamental coloration displayed by their offspring as adults. Mothers experimentally supplemented with dietary carotenoids prior to egg-laying incorporated more carotenoids into eggs, which, due to the antioxidant activity of carotenoids, rendered their embryos less susceptible to free-radical attack during development. These eggs were subsequently more likely to hatch, fledge offspring, produce more sons than daughters, and produce sons who exhibited more brightly colored carotenoid-based beak pigmentation. Provisioned mothers also acquired more colorful beaks, which directly predicted levels of carotenoids found in eggs, thus indicating that these pigments may function not only as physiological ‘damage-protectants’ in adults and offspring but also as morphological signals of maternal reproductive capabilities.

Ensuring safety of home-produced eggs to control salmonellosis in Poland: lessons from an outbreak in September 2011.

PubMed

Zielicka-Hardy, A; Zarowna, D; Szych, J; Madajczak, G; Sadkowska-Todys, M

2012-11-22

Implementation of control measures in line with European Commission regulations has led to a decrease in salmonellosis in the European Union since 2004. However, control programmes do not address laying hens whose eggs are produced for personal consumption or local sale. This article reports an investigatxion of a salmonellosis outbreak linked to home-produced eggs following a family event held in a farm in September 2011 near Warsaw, Poland. In the outbreak, 34 people developed gastroenteritis symptoms. Results from a cohort study indicated a cake, prepared from raw home-produced eggs, as the vehicle of the outbreak. Laboratory analysis identified Salmonella enterica serotype Enteritidis (S. Enteritidis) in stool samples or rectal swabs from 18 of 24 people and in two egg samples. As no food items remained, we used phage typing to link the source of the outbreak with the isolated strains. Seven S. Enteritidis strains analysed (five from attendees and two from eggs) were phage type 21c. Our findings resulted in culling of the infected laying hens and symptomatic pigeons housed next to the hens. Salmonella poses as a public health problem in Poland: control measures should not forget home-produced eggs, as there is a risk of infection from their consumption.

Bioavailability of lutein in corn distillers dried grains with solubles relative to lutein in corn gluten meal based on lutein retention in egg yolk.

PubMed

Shin, Hye Seong; Kim, Jong Woong; Lee, Dong Gu; Lee, Sanghyun; Kil, Dong Yong

2016-08-01

Dietary lutein and its food sources have gained great attention due to its health-promoting effects on humans, especially for certain eye diseases. However, relative bioavailability (RBV) of lutein among lutein-rich feed ingredients that lead to lutein-enriched egg production has not been determined. Thus, the RBV of lutein in corn distillers dried grains with solubles (DDGS) as compared to lutein in corn gluten meal (CGM) was evaluated based on lutein retention in egg yolk. Increasing inclusion levels of DDGS or CGM in diets increased (linear, P < 0.01) Roche colour score and lutein concentrations of egg yolk without affecting laying performance. Multiple regression analysis revealed that the bioavailability of lutein in DDGS was less (P < 0.05) than that of lutein in CGM, with the RBV of lutein in DDGS being 61.6% when the bioavailability of lutein in CGM was assumed to be 100% for lutein retention in egg yolk. The results of the present experiment indicate that the DDGS can be a potential ingredient for laying hens to improve egg yolk colour and lutein concentrations of egg yolk although lutein in DDGS is less bioavailable than lutein in CGM. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Drop of egg production in chickens by experimental infection with an avian metapneumovirus strain PLE8T1 derived from swollen head syndrome and the application to evaluate vaccine.

PubMed

Sugiyama, Miki; Koimaru, Hiroyuki; Shiba, Masahiro; Ono, Eriko; Nagata, Tadashi; Ito, Toshihiro

2006-08-01

Decreases in egg production and increased incidence of abnormal eggs due to malformation of egg shells were observed in specific pathogen free (SPF) 173-day-old laying hens inoculated intravenously with an avian metapneumovirus (aMPV) strain PLE8T1. This strain was derived from an isolate from broiler birds exhibiting swollen head syndrome (SHS). Some SPF birds inoculated with the virus showed, slight diarrhea without any respiratory symptoms. Thus, the PLE8T1 strain was used as a challenge virus to evaluate efficacy of aMPV vaccines. SPF chickens which received a live attenuated aMPV vaccine (NEMOVAC; Merial) at 7 or 77 days old and an inactivated aMPV vaccine (OVO-4; Merial) at 105 days old were protected against poor egg production caused by the challenge with the PLE8T1 strain. Thus, aMPV, the PLE8T1 strain passaged 22 times after isolation, from birds exhibiting SHS, could induce a drop in egg production in laying hens accompanied by malformation of egg shells. It was suggested that this challenge system could be applied to evaluate the efficacy of aMPV vaccine.

Feed Supplementation with Red Seaweeds, Chondrus crispus and Sarcodiotheca gaudichaudii, Reduce Salmonella Enteritidis in Laying Hens

PubMed Central

Kulshreshtha, Garima; Rathgeber, Bruce; MacIsaac, Janice; Boulianne, Martine; Brigitte, Lehoux; Stratton, Glenn; Thomas, Nikhil A.; Critchley, Alan T.; Hafting, Jeff; Prithiviraj, Balakrishnan

2017-01-01

Salmonella Enteritidis is vertically transmitted to eggs from laying hens through infected ovaries and oviducts. S. Enteritidis can also penetrate the eggshell from contaminated feces. Reducing S. Enteritidis in laying hens is vital to provide safer eggs and minimize the spread of salmonellosis to humans. Antibiotics have been widely used to control bacterial diseases in broilers and laying hens. However, there is a major concern that the use of antibiotics leads to the development of antibiotic resistance and adverse effects on microbiota of the treated birds. Thus, there is an interest in developing alternatives to antibiotics, such as dietary prebiotics. In the present study, feed supplemented with the red seaweeds: Chondrus crispus (CC) or Sarcodiotheca gaudichaudii (SG), was offered to laying hens late in production to control S. Enteritidis. Diets contained one of the following; 2% or 4% Chondrus crispus (CC2, and CC4, respectively) or Sarcodiotheca gaudichaudii (SG2 and SG4, respectively). Chlortetracycline was used in the positive control diet. During week-4, 48 birds were orally challenged with 2 × 109 CFU/mL of S. Enteritidis. Eggs and fecal samples were collected 1, 3, 5, and 7 days’ post inoculation. Birds were euthanized and organs (ceca, ovary, liver, and spleen) were sampled and analyzed for the presence of S. Enteritidis, 7 days’ post inoculation. Results showed that seaweed reduced the negative effect on body weight and egg production in S. Enteritidis-challenged laying hens. Analysis of fecal samples showed that the antibiotic (CTC) reduced S. Enteritidis in the intestinal tract and fecal samples, 3 days’ post inoculation. Fecal samples from Chlortetracycline and CC4 supplemented birds tested negative for S. Enteritidis on days 5 and 7 post inoculation (lowest detection limit = 10-1). S. Enteritidis colonization in the ceca was also significantly reduced in birds fed CC (4%) and Chlortetracycline. Blood serum profiles revealed that there were no significant differences in serum aspartate aminotransferase (AST) and sodium. However, the level of serum immunoglobulin (IgA) was higher in the CC4 treatment. The relative abundance of Lactobacillus acidophilus was significantly higher in CC4 while, the abundance of the pathogenic bacteria, Clostridium perfringens and Salmonella Enteritidis were reduced compared to control. Results indicate that feed supplemented with 4% CC is effective in providing protection against Salmonella Enteritidis colonization in laying hens. PMID:28443073

Analysing the oviposition behaviour of malaria mosquitoes: design considerations for improving two-choice egg count experiments.

PubMed

Okal, Michael N; Lindh, Jenny M; Torr, Steve J; Masinde, Elizabeth; Orindi, Benedict; Lindsay, Steve W; Fillinger, Ulrike

2015-06-20

Choice egg-count bioassays are a popular tool for analysing oviposition substrate preferences of gravid mosquitoes. This study aimed at improving the design of two-choice experiments for measuring oviposition substrates preferences of the malaria vector Anopheles gambiae senso lato, a mosquito that lays single eggs. In order to achieve high egg-laying success of female An. gambiae sensu stricto (s.s.) and Anopheles arabiensis mosquitoes in experiments, four factors were evaluated: (1) the time provided for mating; (2) the impact of cage size, mosquito age and female body size on insemination; (3) the peak oviposition time; and, (4) the host sources of blood meal. Choice bioassays, with one mosquito released in each cage containing two oviposition cups both with the same oviposition substrate (100 ml water), were used to measure and adjust for egg-laying characteristics of the species. Based on these characteristics an improved design for the egg-count bioassay is proposed. High oviposition rates [84%, 95% confidence interval (CI) 77-89%] were achieved when 300 male and 300 blood-fed female An. gambiae s.s. were held together in a cage for 4 days. The chances for oviposition dropped (odds ratio 0.30; 95% CI 0.14-0.66) when human host source of blood meal was substituted with a rabbit but egg numbers per female were not affected. The number of eggs laid by individual mosquitoes was overdispersed (median = 52, eggs, interquartile range 1-214) and the numbers of eggs laid differed widely between replicates, leading to a highly heterogeneous variance between groups and/or rounds of experiments. Moreover, one-third of mosquitoes laid eggs unequally in both cups with similar substrates giving the illusion of choice. Sample size estimations illustrate that it takes 165 individual mosquitoes to power bioassays sufficiently (power = 0.8, p = 0.05) to detect a 15% shift in comparative preferences of two treatments. Two-choice egg count bioassays with Anopheles are best done with a two-tier design that (1) implements a parallel series of experiments with mosquitoes given a choice of two identical substrates choices and, (2) uses a single mosquito in each test cage rather than groups of mosquitoes to assess the preference of a test or control solution. This approach, with sufficient replication, lowers the risk detecting pseudopreferences.

Dietary safflower phospholipid reduces liver lipids in laying hens.

PubMed

An, B K; Nishiyama, H; Tanaka, K; Ohtani, S; Iwata, T; Tsutsumi, K; Kasai, M

1997-05-01

This experiment was conducted to determine the effects of dietary safflower phospholipids (crude safflower phospholipid and purified safflower phospholipid) on performance and lipid metabolism of laying hens. Sixty-week-old Single Comb White Leghorn laying hens were divided into four groups of seven birds each, and were given one of four experimental diets containing 5% beef tallow (served as a control, tallow), a mixture of safflower oil and palm oil (SP-oil), crude safflower phospholipid (Saf-PLcrude), or purified safflower phospholipid (Saf-PL) for 7 wk. Egg production ratio and daily egg mass were significantly higher in hens fed Saf-PLcrude diets than in hens of the other diet groups. There were no significant differences in egg weight among groups. Liver cholesterol and triglyceride contents were significantly decreased in all treated groups as compared with the control. The activity of hepatic 3-hydroxy-3 methylglutaryl coenzyme A reductase was the highest in hens fed the Saf-PLcrude diet. Serum esterified cholesterol concentration was decreased by feeding of SP-oil, Saf-PLcrude, or Saf-PL diets. Serum lecithin-cholesterol acyltransferase activity was highest in hens fed the tallow diet. Excreta neutral steroid excretion was significantly increased in the Saf-PLcrude or Saf-PL diet groups, although acidic steroid excretion was not affected by dietary treatments. Total cholesterol, triglyceride, and phospholipid contents in egg yolks were not different for any dietary treatments. The fatty acid compositions of egg yolks from hens fed Saf-PLcrude diets were not different with those fed the SP-oil diet, although eggs of hens fed the Saf-PL diet showed lower total polyunsaturated fatty acids. These results suggest that dietary safflower phospholipids may be a valuable ingredient to layers for reducing liver triglycerides and serum cholesterol without any adverse effects.

Sampling Considerations for Designing Aedes aegypti (Diptera: Culicidae) Oviposition Studies in Iquitos, Peru: Substrate Preference, Diurnal Periodicity, and Gonotrophic Cycle Length

PubMed Central

WONG, JACKLYN; ASTETE, HELVIO; MORRISON, AMY C.; SCOTT, THOMAS W.

2011-01-01

When devising methods to sample Aedes aegypti (L.) eggs from naturally-occurring containers to investigate selective oviposition, failure to take into account certain aspects of Ae. aegypti behavior can bias study inferences. In Iquitos, Peru, we tested three assumptions related to designing Ae. aegypti oviposition field studies, as follows: 1) lining containers with paper as an oviposition substrate does not affect oviposition; 2) diurnal egg-laying activity peaks in the late afternoon or early evening, and there is little oviposition during midday; and 3) the gonotrophic cycle length of wild females averages from 3 to 4 d. When wild females were presented with containers lined and unlined with paper toweling, the presence of paper increased oviposition in plastic and metal containers, but had no effect in cement containers. Recording the number of eggs laid by Ae. aegypti every 2 h throughout the day delineated a bimodal diurnal oviposition pattern, with a small morning peak, decreased activity during midday, and a predominant peak in the late afternoon and evening from 16:00 to 20:00 h. Daily monitoring of captive individual F0 females revealed that the gonotrophic cycle length was typically 3– 4 d for the Iquitos population. These findings will be used to adjust field study design to 1) account for sampling eggs using paper toweling, and 2) determine the time of day and number of days over which to sample Ae. aegypti eggs. We explored how failure to consider these behaviors could potentially bias field assessments of oviposition preferences. PMID:21337947

Evaluation of the Bacterial Diversity in Cecal Contents of Laying Hens Fed Various Molting Diets Using Bacterial Tag-Encoded FLX Amplicon Pyrosequencing (bTEFAP)

USDA-ARS?s Scientific Manuscript database

Laying hens are typically induced to molt in order to begin a new egg-laying cycle by withdrawing feed for up to 12-14 d. Fasted hens are more susceptible to colonization and tissue invasion by Salmonella Enteriditis. Much of this increased incidence in fasted hens is thought to be due to changes ...

Evolution and manipulation of parasitoid egg load.

PubMed

Gandon, Sylvain; Varaldi, Julien; Fleury, Frédéric; Rivero, Ana

2009-11-01

In proovigenic parasitoids such as Leptopilina boulardi, the female emerges with a limited egg load and no further eggs are produced during its adult life. A female thus runs the risk of exhausting this limited supply of eggs before the end of her life. Given that the production of an egg is costly, what is the evolutionarily stable egg load at emergence? This question has attracted a lot of attention in the last decade. Here, we analyze a model that allows us to track both the evolution and the population dynamics of a solitary, proovigenic parasitoid. First, we show how host-parasitoid dynamics feedbacks on the evolution of parasitoid egg load. Second, we use this model to consider the situation in which the parasitoid can be infected by a virus that manipulates the oviposition behavior of the females. In particular, we model the effect of the LbFV virus in L. boulardi, a virus that is known to enhance its horizontal transmission by increasing superparasitism (i.e., the laying of eggs in a host already parasitized). Specifically, we model (1) the effect of the virus on parasitoid egg load strategies, and (2) the evolution of egg load manipulation by the virus. This analysis yields two alternative, yet not mutually exclusive, adaptive explanations for the observation that females infected by the virus harbor higher egg loads than uninfected females. Infected females could either respond plastically to the infection status, or be manipulated by the virus. Further experimental work is required to distinguish between these two hypotheses. In a broader context, we present a general theoretical framework that allows us to study the epidemiology, the evolution, the coevolution, and the evolution of manipulation of various reproductive strategies of parasitoids.

Feeding ecology of pintail hens during reproduction

USGS Publications Warehouse

Krapu, G.L.

1974-01-01

Food supply has been acknowledged as one of eight major external factors regulating the sexual cycles of birds (Marshall 1961). Several hypotheses have been advanced to explain the role of food supply as an ultimate factor regulating breeding (Marshall 1951; Lack 1954, 1968; Wynne-Edwards 1962; and others). Another potential influence of food is its being a proximate stimulus to breeding. When certain foods become available they may act as a stimulus as the female requires them to meet her dietary needs during egg formation. Lack (1966a: 24) suggested that the average date of laying by the Great Tit (Parus major) probably resulted from a correlation between spring temperatures and the time of appearance of the insect foods the adult females need to form eggs. He also cited other passerines whose breeding was affected by food supply available to the female. In waterfowl it has been suggested that laying females require invertebrate foods (Moyle 1961, Leitch 1964). If true, this implies that the timing of laying is influenced by those environmental changes that affect food supply.The Pintail (Anas acuta) lives primarily on plant foods during much of the year (Martin et al. 1951); thus a study of feeding ecology during the nesting season provided an opportunity to evaluate the significance of an invertebrate food source to females during the period of egg formation. Marshall (1951) stated that essentially vegetarian species appear compelled to switch at least partially to a heavier protein diet when feeding their developing young. Production of a clutch of eggs, like tissue growth in the young, requires a special dietary need that presumably should be reflected in the diet of vegetarian species during the period that eggs are being formed. This paper describes the diet of the female Pintail prior to, during, and after laying and discusses the impact of certain environmental and physiological changes on Pintail breeding.

Effect of different dietary energy and protein sources on antioxidant status, fresh yolk fatty acid profile and microstructure of salted yolks in laying ducks.

PubMed

Ruan, D; Hu, Y J; Fouad, A M; Lin, C X; Xu, Z P; Chen, W; Fan, Q L; Xia, W G; Wang, S; Wang, Y; Yang, L; Zheng, C T

2018-01-08

The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and reduced the quality of salted yolks.

Sensory quality of mayonnaise formulated with eggs produced by laying hens fed diet enriched with purslane meal (Portulaca oleracea)

NASA Astrophysics Data System (ADS)

Kartikasari, L. R.; Hertanto, B. S.; Nuhriawangsa, A. M. P.

2018-01-01

The objective of the study was to assess the sensory quality of mayonnaise formulated by egg yolks produced by hens fed purslane meal as a source of omega-3 (n-3) fats, alpha-linolenic acid. Eggs used were produced by Hy-Line Brown hens (38 weeks old) fed five diets suplemented with 0, 2, 4, 6 and 8% purslane meal. A total of 40 eggs of day 29 (n = 8 eggs for each treatment) were collected to formulate mayonnaise. The ingredient composition of mayonnaise was 14% egg yolks, 9% vinegar, 74% corn oil, 1% salt, 1% sugar, and 1% mustard. The parameters included colour, emulsion stability, texture, homogeneity, aroma, taste and flavour of mayonnaise. The findings of sensory evaluation by quantitative descriptive analysis showed that the use of egg yolk from hens fed dietary purslane meal up to 8% resulted in a significant effect on the yellow color of mayonnaise, but did not significantly affect emulsion stability, texture, homogeneity, aroma, taste, and flavour. Based on consumer preference, consumers did not detect any differences in the sensory characteristics between mayonnaise prepared from control eggs and those formulated with eggs produced from dietary treatment. Apparently, there was an increase in colour liking by inclusion of purslane meal. In conclusion, eggs from laying hens fed diets supplemented with purslane meal improved the colour intensity of mayonnaise. Mayonnaise formulation using eggs from diets added with Portulaca oleraceae meal up to a level of 8% can be applied without influencing mayonnaise sensory characteristics and consumer acceptance.

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.

Reed warbler hosts fine-tune their defenses to track three decades of cuckoo decline.

PubMed

Thorogood, Rose; Davies, Nicholas B

2013-12-01

Interactions between avian hosts and brood parasites can provide a model for how animals adapt to a changing world. Reed warbler (Acrocephalus scirpaceus) hosts employ costly defenses to combat parasitism by common cuckoos (Cuculus canorus). During the past three decades cuckoos have declined markedly across England, reducing parasitism at our study site (Wicken Fen) from 24% of reed warbler nests in 1985 to 1% in 2012. Here we show with experiments that host mobbing and egg rejection defenses have tracked this decline in local parasitism risk: the proportion of reed warbler pairs mobbing adult cuckoos (assessed by responses to cuckoo mounts and models) has declined from 90% to 38%, and the proportion rejecting nonmimetic cuckoo eggs (assessed by responses to model eggs) has declined from 61% to 11%. This is despite no change in response to other nest enemies or mimetic model eggs. Individual variation in both defenses is predicted by parasitism risk during the host's egg-laying period. Furthermore, the response of our study population to temporal variation in parasitism risk can also explain spatial variation in egg rejection behavior in other populations across Europe. We suggest that spatial and temporal variation in parasitism risk has led to the evolution of plasticity in reed warbler defenses. © 2013 The Authors. Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Tri-trophic movement of carotenoid pigments from host plant to the parasitoid of a caterpillar

USDA-ARS?s Scientific Manuscript database

Insect parasitoids normally produce white-colored eggs. Habrobracon gelechiae (Hymenoptera: Braconidae) is a gregarious ectoparasitoid of various caterpillars that lays yellow eggs when its larvae developed on leaf-fed Choristoneura rosaceana and Epiphyas postvittana (both Lepidoptera: Tortricidae) ...

Arrested embryonic development: a review of strategies to delay hatching in egg-laying reptiles

PubMed Central

Rafferty, Anthony R.; Reina, Richard D.

2012-01-01

Arrested embryonic development involves the downregulation or cessation of active cell division and metabolic activity, and the capability of an animal to arrest embryonic development results in temporal plasticity of the duration of embryonic period. Arrested embryonic development is an important reproductive strategy for egg-laying animals that provide no parental care after oviposition. In this review, we discuss each type of embryonic developmental arrest used by oviparous reptiles. Environmental pressures that might have directed the evolution of arrest are addressed and we present previously undiscussed environmentally dependent physiological processes that may occur in the egg to bring about arrest. Areas for future research are proposed to clarify how ecology affects the phenotype of developing embryos. We hypothesize that oviparous reptilian mothers are capable of providing their embryos with a level of phenotypic adaptation to local environmental conditions by incorporating maternal factors into the internal environment of the egg that result in different levels of developmental sensitivity to environmental conditions after they are laid. PMID:22438503

Chapter 9: The ecology of brown-headed cowbirds and their effects on southwestern willow flycatchers

Treesearch

J. C. Uyehara; Mary J. Whitfield; Lloyd Goldwasser

2000-01-01

Brown-headed cowbirds (Molothrus ater) are obligate brood-parasites, that is, female cowbirds lay their eggs in nests of other species. If the cowbird eggs are accepted, the host pair may raise the young cowbird, often at a reduction of the hosts' reproductive success. Cowbird females are also known to remove host eggs and nestlings from nests,...

Impact of vaccination on infection with Vietnam H5N1 high pathogenicity avian influenza virus in hens and the eggs they lay

USDA-ARS?s Scientific Manuscript database

High pathogenicity avian influenza virus (HPAIV) infections in chickens decrease egg production and eggs that are laid contain HPAIV. Vaccination once or twice was examined as a way to protect chickens from Vietnamese H5N1 HPAIV. Eighty-three percent of hens without vaccination died within 3 days ...

Bacteriological contamination, dirt, and cracks of eggshells in furnished cages and noncage systems for laying hens: an international on-farm comparison.

PubMed

De Reu, K; Rodenburg, T B; Grijspeerdt, K; Messens, W; Heyndrickx, M; Tuyttens, F A M; Sonck, B; Zoons, J; Herman, L

2009-11-01

For laying hens, the effects of housing system on bacterial eggshell contamination and eggshell quality is almost exclusively studied in experimental hen houses. The aim of this study was to compare eggshell hygiene and quality under commercial conditions. Six flocks of laying hens in furnished cages and 7 flocks in noncage systems were visited when hens were about 60 wk of age. Farms from Belgium, the Netherlands, and Germany were included in the study. The following parameters were determined on eggs sampled at the egg belts: 1) bacterial eggshell contamination, as expressed by total count of aerobic bacteria and number of Enterobacteriaceae; 2) proportion of dirty eggs; and 3) proportion of cracked eggs and eggs with microcracks. Considerable within-flock differences were found in eggshell contamination with total count of aerobic bacteria, both for furnished cages (P < or = 0.001, range 4.24 to 5.22 log cfu/eggshell) and noncage systems (P < or = 0.001, range 4.35 to 5.51 log cfu/eggshell). On average, lower levels of contamination with total count of aerobic bacteria (4.75 vs. 4.98 log cfu/eggshell; P < or = 0.001) were found on eggshells from furnished cages compared with noncage systems. Concerning Enterobacteriaceae, no significant difference in average eggshell contamination between both systems could be shown. The total percentage of cracked eggs was higher (P < or = 0.01) in furnished cages (7.8%) compared with noncage systems (4.1%). This was, however, due to the high percentage of cracked eggs (24%) observed on one of the furnished cage farms. We conclude that bacteriological eggshell contamination and percentage of cracked eggs differed substantially between individual farms using the same housing system. This may also explain some discrepancies between the findings of the present study versus some findings of previous experimental studies or studies on a small number of farms. Although statistically significant, the average differences in bacteriological contamination of nest eggs between both housing systems have limited microbiological relevancy.

Influence of mate preference and laying order on maternal allocation in a monogamous parrot species with extreme hatching asynchrony.

PubMed

Lahaye, Stefanie E P; Eens, Marcel; Iserbyt, Arne; Groothuis, Ton G G; de Vries, Bonnie; Müller, Wendt; Pinxten, Rianne

2015-05-01

It is well established that in many avian species, prenatal maternal resource allocation varies both between and within clutches and may affect offspring fitness. Differential allocation of maternal resources, in terms of egg weight and yolk composition, may therefore allow the female to adjust brood reduction and to fine-tune reproductive investment in accordance with the expected fitness returns. The adaptive value of such maternal resource allocation is thought to be context-dependent as well as species-specific. We investigated the effects of female preference for her mate on the allocation of prenatal maternal resources in the budgerigar, Melopsittacus undulatus, a monogamous species of parrot that shows an extreme hatching asynchrony. We assessed mate preferences in a two-way preference test and allowed females two breeding rounds: one with the preferred and one with the non-preferred partner. We found no effect of preference on either latency to lay or clutch size, but females mated with the preferred partner laid eggs that contained significantly more yolk. Their eggs also contained significantly more androstenedione but not testosterone. Our results suggest that in this species, female preference may influence maternal resource allocation, and that the functional roles of each androgen in the yolk should be considered separately. In addition, we found a significant effect of laying order on egg and yolk weight as well as on yolk testosterone and androstenedione levels. These measures, however, did not change linearly with the laying order and render it unlikely that female budgerigars compensate for the extreme hatching asynchrony by adjusting within-clutch allocation of prenatal maternal resources. Copyright © 2015 Elsevier Inc. All rights reserved.

The effect of perch availability during pullet rearing and egg laying on musculoskeletal health of caged White Leghorn hens.

PubMed

Hester, P Y; Enneking, S A; Haley, B K; Cheng, H W; Einstein, M E; Rubin, D A

2013-08-01

A major skeletal problem of conventionally caged hens is increased susceptibility to osteoporosis mainly due to lack of exercise. Osteoporosis is characterized by a progressive decrease in mineralized structural bone. Whereas considerable attention has been given to enriching laying cages, little research has been conducted on providing caged pullets with furnishments, in particular perches. The objective of the current study was to determine if metal perches during all or part of the life cycle of White Leghorns affected hen musculoskeletal health, especially at end of lay. Treatments during the pullet phase (hatch to 16.9 wk) entailed cages with and without perches. Four treatments were used during the laying phase (17 to 71 wk of age). Treatment 1 chickens never had access to perches at any point during their life cycle, typical of egg industry practices in the United States for conventional cages. Treatment 2 chickens had access to perches only during the egg-laying phase, which was from 17 to 71 wk of age. Treatment 3 chickens had access to perches only during the pullet phase (0 to 16.9 wk of age). Treatment 4 chickens had perch access throughout their entire life cycle (0 to 71 wk of age). Musculoskeletal health was assessed by measuring muscle weights, bone mineralization, bone fracture incidence, and keel bone deviations. Muscle deposition of 71-wk-old hens increased when given access to perches as pullets. Bone mineralization of 71-wk-old hens also increased if given perch access as adults. However, the disadvantage of the adult perch was the higher incidence of keel deviations and keel fractures at end of lay. The increase in bone mineralization of the keel bone as a result of perch access during the pullet and laying phases was not great enough to prevent a higher incidence of keel bone fractures at end of lay. Perch redesign and placement of perches within the cage to minimize keel fractures and deviations are possible solutions.

Bemisia tabaci females from the Mediterranean (Q) species detect and avoid laying eggs in the presence of pyriproxyfen, a juvenile hormone analogue.

PubMed

Moshitzky, Pnina; Morin, Shai

2014-10-01

Pyriproxyfen, a juvenile hormone analogue, disrupts embryogenesis, metamorphosis and adult formation in Bemisia tabaci, but does not directly affect adult females. The effect of pyriproxyfen on egg-laying preference and performance of B. tabaci females and the influence of resistance to pyriproxyfen on these reproductive behaviours were studied. Choice experiments utilising cotton plants treated and not treated with pyriproxyfen revealed a significant preference for egg laying on non-treated plants both by resistant and susceptible females. No-choice assays indicated a reduction of ∼60% in the number of eggs laid on pyriproxyfen-treated plants by both resistant and susceptible females. The reduction in oviposition on treated plants was not accompanied with reduced expression of the vitellogenin gene or a delay in oocyte maturation, but significant accumulation of mature oocytes in the ovaries was observed, and could be reversed by transferring the females to non-treated plants. Pyriproxyfen caused reduced oviposition and enhanced mature oocyte accumulation in pyriproxyfen-resistant and pyriproxyfen-susceptible females. These findings can be explained by two alternative mechanisms: pyriproxyfen-regulated physiological arrest of oviposition, involving hormonal regulation of myotrophic factors, or the hierarchy-threshold behavioural theory of host choice, in which pyriproxyfen-treated plants are defined as low-quality hosts. Aspects of application are discussed. © 2013 Society of Chemical Industry.

[Separation and identification of red pigments in natural red yolk of duck's eggs by HPLC-MS-MS].

PubMed

Liu, Liangzhong; Zhang, Min; Peng, Guanghua; Wang, Haibin; Zhang, Shenghua

2004-05-01

The natural red yolk of duck's eggs is produced by the laying duck in the lake areas in southward of China. In the laying duck breeding areas such as Honghu, Jianli, Xiantao, Tianmen and Hanchuan citys in Hubei Province, the culturists are used to feeding fresh pondweeds to the laying ducks. The yolk of duck's eggs is natural red with the chrominance reaching up to and/or above RCF (Roche Yolk Color Fan) 15. The red pigment components of natural red yolk of duck's eggs were separated and identified by thin layer chromatography (TLC), high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) and high resolution electron impact-mass spectrometry (EI-MS). Four isomers of red pigments were separated by HPLC on a RP-C18 column with methanol-water (99.5:0.5, v/v) as mobile phase. The lambda(max) of the four components were 482, 488, 496, 501 nm, respectively, and all of them were single peak on chromatogram. They had the same molecular mass (Mr = 562), and had the same fragment peaks of MS2 with rhodoxanthin. The molecular formula of red pigments was determined as C40H50O2 by high resolution EI-MS. The results indicate that the red pigment is rhodoxanthin, and they are all cis-isomers of rhodoxanthin.

Effects of karaya saponin and Rhodobacter capsulatus on yolk cholesterol in laying hens.

PubMed

Afrose, S; Hossain, M S; Maki, T; Tsujii, H

2010-06-01

1. It has been reported that karaya saponin and Rhodobacter capsulatus individually have hypocholesterolaemic activity in laying hens. This study focuses on the effect of adding karaya saponin with R. capsulatus to hen's diet with regard to serum and egg yolk cholesterol and triglycerides. 2. A total of 56 Boris Brown laying hens were divided into 7 groups at 20 weeks of age. Combinations of 25, 50, 75 mg kg(-1) karaya saponin and R. capsulatus 200 and 400 mg kg(-1) were used as treatment groups. 3. After 8 weeks of supplementation, the effects of all the combinations of karaya saponin and R. capsulatus on serum and egg yolk cholesterol, triglycerides, and high-density lipoprotein (HDL)-cholesterol were greater than either karaya saponin or R. capsulatus alone. The combination of karaya saponin 50 mg kg(-1)+ R. capsulatus 400 mg kg(-1) exhibited the greatest reduction of serum (325%) and yolk (225%) cholesterol and the greatest increase of faecal, liver bile acids and yolk fatty acid (oleic, linoleic and linolenic) concentrations. In addition, egg production and yolk colour were significantly improved by the combined use of karaya saponin and R. capsulatus supplementation. 4. Therefore, the dietary supplementation of karaya saponin and R. capsulatus may lead to the production of a low-cholesterol egg, with production performance maintained at a standard level.

Estimation of the rate of egg contamination from Salmonella-infected chickens.

PubMed

Arnold, M E; Martelli, F; McLaren, I; Davies, R H

2014-02-01

Salmonella enterica serovar Enteritidis (S. Enteritidis) is one of the most prevalent causes for human gastroenteritis and is by far the predominant Salmonella serovar among human cases, followed by Salmonella Typhimurium. Contaminated eggs produced by infected laying hens are thought to be the main source of human infection with S. Enteritidis throughout the world. Although previous studies have looked at the proportion of infected eggs from infected flocks, there is still uncertainty over the rate at which infected birds produce contaminated eggs. The aim of this study was to estimate the rate at which infected birds produce contaminated egg shells and egg contents. Data were collected from two studies, consisting of 15 and 20 flocks, respectively. Faecal and environmental sampling and testing of ovaries/caeca from laying hens were carried out in parallel with (i) for the first study, testing 300 individual eggs, contents and shells together and (ii) for the second study, testing 4000 eggs in pools of six, with shells and contents tested separately. Bayesian methods were used to estimate the within-flock prevalence of infection from the faecal and hen post-mortem data, and this was related to the proportion of positive eggs. Results indicated a linear relationship between the rate of contamination of egg contents and the prevalence of infected chickens, but a nonlinear (quadratic) relationship between infection prevalence and the rate of egg shell contamination, with egg shell contamination occurring at a much higher rate than that of egg contents. There was also a significant difference in the rate of egg contamination between serovars, with S. Enteritidis causing a higher rate of contamination of egg contents and a lower rate of contamination of egg shells compared to non-S. Enteritidis serovars. These results will be useful for risk assessments of human exposure to Salmonella-contaminated eggs. © 2013 Crown copyright. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland.

The evolution of egg colour and patterning in birds.

PubMed

Kilner, R M

2006-08-01

Avian eggs differ so much in their colour and patterning from species to species that any attempt to account for this diversity might initially seem doomed to failure. Here I present a critical review of the literature which, when combined with the results of some comparative analyses, suggests that just a few selective agents can explain much of the variation in egg appearance. Ancestrally, bird eggs were probably white and immaculate. Ancient diversification in nest location, and hence in the clutch's vulnerability to attack by predators, can explain basic differences between bird families in egg appearance. The ancestral white egg has been retained by species whose nests are safe from attack by predators, while those that have moved to a more vulnerable nest site are now more likely to lay brown eggs, covered in speckles, just as Wallace hypothesized more than a century ago. Even blue eggs might be cryptic in a subset of nests built in vegetation. It is possible that some species have subsequently turned these ancient adaptations to new functions, for example to signal female quality, to protect eggs from damaging solar radiation, or to add structural strength to shells when calcium is in short supply. The threat of predation, together with the use of varying nest sites, appears to have increased the diversity of egg colouring seen among species within families, and among clutches within species. Brood parasites and their hosts have probably secondarily influenced the diversity of egg appearance. Each drives the evolution of the other's egg colour and patterning, as hosts attempt to avoid exploitation by rejecting odd-looking eggs from their nests, and parasites attempt to outwit their hosts by laying eggs that will escape detection. This co-evolutionary arms race has increased variation in egg appearance both within and between species, in parasites and in hosts, sometimes resulting in the evolution of egg colour polymorphisms. It has also reduced variation in egg appearance within host clutches, although the benefit thus gained by hosts is not clear.

Egg laying characteristics, egg weight, embryo development, hatching weight and post-hatch growth in relation to oviposition time of broiler breeders.

PubMed

Akil, R; Zakaria, A H

2015-05-01

Two experiments were conducted to determine egg laying characteristics and the effects of oviposition time on egg weight, embryo development and post-hatch growth in broiler breeders. In experiment 1, eggs collected for 3 consecutive days on hourly basis between 06:30 and 17:30h were categorized to early, middle and late oviposition times in the clutch. In experiment 2, eggs were incubated to study embryo development, remaining albumen, liver weight, heart weight and the tibia length of embryos at 12, 14, 16 and 18 days of incubation as well as the body weight of hatchlings and chickens at 7, 21 and 42 days of age in relation to oviposition time. About 76% of nest eggs were laid from 06:30 to 11:30h. A similar pattern was observed in floor eggs. Egg weight decreased (P<0.01) with advanced position in the clutch. Generally, oviposition time had no effect on embryo growth parameters. At hatch, body weight of chicks derived from eggs of late oviposition times was less (P<0.01) than that of chicks from eggs produced earlier in the clutch. From 3-week-old onwards, chickens of early oviposition time sustained heavier (P<0.05) weight than chickens of middle oviposition time whereas chickens of late oviposition time obtained a middle weight. Differences in egg weights, body weight at hatch and post-hatch growth due to time of oviposition suggest that oviposition time together with incubation conditions should be considered for obtaining greater uniformity and growth of chickens. Copyright © 2015 Elsevier B.V. All rights reserved.

Genetic loci inherited from hens lacking maternal behaviour both inhibit and paradoxically promote this behaviour.

PubMed

Basheer, Atia; Haley, Chris S; Law, Andy; Windsor, Dawn; Morrice, David; Talbot, Richard; Wilson, Peter W; Sharp, Peter J; Dunn, Ian C

2015-12-30

A major step towards the success of chickens as a domesticated species was the separation between maternal care and reproduction. Artificial incubation replaced the natural maternal behaviour of incubation and, thus, in certain breeds, it became possible to breed chickens with persistent egg production and no incubation behaviour; a typical example is the White Leghorn strain. Conversely, some strains, such as the Silkie breed, are prized for their maternal behaviour and their willingness to incubate eggs. This is often colloquially known as broodiness. Using an F2 linkage mapping approach and a cross between White Leghorn and Silkie chicken breeds, we have mapped, for the first time, genetic loci that affect maternal behaviour on chromosomes 1, 5, 8, 13, 18 and 19 and linkage group E22C19W28. Paradoxically, heterozygous and White Leghorn homozygous genotypes were associated with an increased incidence of incubation behaviour, which exceeded that of the Silkie homozygotes for most loci. In such cases, it is likely that the loci involved are associated with increased egg production. Increased egg production increases the probability of incubation behaviour occurring because egg laying must precede incubation. For the loci on chromosomes 8 and 1, alleles from the Silkie breed promote incubation behaviour and influence maternal behaviour (these explain 12 and 26% of the phenotypic difference between the two founder breeds, respectively). The over-dominant locus on chromosome 5 coincides with the strongest selective sweep reported in chickens and together with the loci on chromosomes 1 and 8, they include genes of the thyrotrophic axis. This suggests that thyroid hormones may play a critical role in the loss of incubation behaviour and the improved egg laying behaviour of the White Leghorn breed. Our findings support the view that loss of maternal incubation behaviour in the White Leghorn breed is the result of selection for fertility and egg laying persistency and against maternal incubation behaviour.

Vaccine to fibroblast growth factor 23 peptides increases eggshell strength.

PubMed

Ren, Z Z; Piepenburg, A J; Bütz, D E; Claus, J R; Cook, M E

2018-03-01

Strategies that would increase eggshell quality could be of considerable value to egg producers. This research demonstrated the effective use of fibroblast growth factor 23 (FGF-23) peptide vaccines to increase eggshell quality of Single Comb White Leghorn laying hens (from 69 to 72 wk of age). Hens, fed a standard diet (containing 900 IU/kg vitamin D3), were intramuscularly injected (and boosted) with either a control vaccine (n = 14 hens) or one of 2 FGF-23 peptide vaccines (peptides NP1, GMNPPPYS; and NP7, YTSTERNSFH; n = 15 hens for each peptide). During peak antibody titer, eggs were collected for shell and internal quality analysis, hens were artificially inseminated, and the hatchability of fertilized eggs was determined. Laying hens vaccinated with either FGF-23 peptide NP1 or NP7 had increased (P < 0.05) plasma phosphate level (mmol/L; NP1 = 1.74, NP7 = 1.76, control = 1.47), egg specific gravity (NP1 = 1.083, NP7 = 1.083, control = 1.079), and eggshell strength (g of force; NP1 = 4002, NP7 = 4157, control = 3102) when compared to control vaccinated hens. FGF-23 peptide NP1 vaccinated hens also had increased eggshell thickness (mm, P < 0.001), shell weight (g, P = 0.032), and shell index (% of whole egg, P = 0.023) when compared to control vaccinated hens. FGF-23 peptide NP7 vaccinated hens tended to have decreased eggshell weight (P = 0.064) when compared to control vaccinated hens. Hatchability of fertilized eggs was not affected in incubations 1 and 3, but tended to be decreased (P = 0.097) by FGF-23 peptide NP1 vaccination in incubation 2. In conclusion, vaccines to FGF-23 peptides increased eggshell quality of laying hens with minimal adverse effects on egg internal quality. The effect of FGF-23 peptide vaccination on hatchability remains to be clarified.

Effect of air velocity on laying hen performance and egg quality

USDA-ARS?s Scientific Manuscript database

Increasing convective cooling can improve performance and thermal comfort of commercial poultry when weather or system design limit cooling through other means such as evaporative cooling. Previous work in young hens showed increased egg production rate as feed intake is maintained under heat stres...

Competing dopamine neurons drive oviposition choice for ethanol in Drosophila.

PubMed

Azanchi, Reza; Kaun, Karla R; Heberlein, Ulrike

2013-12-24

The neural circuits that mediate behavioral choice evaluate and integrate information from the environment with internal demands and then initiate a behavioral response. Even circuits that support simple decisions remain poorly understood. In Drosophila melanogaster, oviposition on a substrate containing ethanol enhances fitness; however, little is known about the neural mechanisms mediating this important choice behavior. Here, we characterize the neural modulation of this simple choice and show that distinct subsets of dopaminergic neurons compete to either enhance or inhibit egg-laying preference for ethanol-containing food. Moreover, activity in α'β' neurons of the mushroom body and a subset of ellipsoid body ring neurons (R2) is required for this choice. We propose a model where competing dopaminergic systems modulate oviposition preference to adjust to changes in natural oviposition substrates.

Yolk testosterone and corticosterone in hierarchical follicles and laid eggs of Japanese quail exposed to long-term restraint stress.

PubMed

Okuliarová, Monika; Sárniková, Bozena; Rettenbacher, Sophie; Skrobánek, Peter; Zeman, Michal

2010-01-01

Environmental and behavioural stimuli experienced by egg-laying female birds contribute to intra- and inter-female differences in hormones in the egg yolk with consequences for offspring development. The understanding of physiological mechanisms underlying yolk hormone deposition can aid progress in this field. In our study, we measured the concentration of testosterone and corticosterone in hierarchical follicles and egg yolks of Japanese quail in control and chronic stress conditions. Experimental females were reared under hypodynamia, a model situation for restraint stress, from day 3 to 63 days of age. For yolk hormone analysis, four largest follicles of ovarian hierarchy (F1-F4), eggs present in the oviduct and eggs laid on the day before were collected. In chronically stressed birds, yolk testosterone concentrations decreased from F2 onwards, while yolk corticosterone content was increased from the beginning to the end of egg formation. The follicular profile of hormones suggested testosterone transfer into the yolk directly from granulosa and theca cells, with the highest accumulation during a period 48-72 h before laying the egg. Yolk corticosterone was accumulated from maternal plasma preferentially in early stages of follicular development under control conditions and also in last stages of egg formation under stress conditions. These specific patterns of hormone deposition indicate periods when stimuli experienced by female can substantially modify hormonal content of eggs. Lower testosterone and increased corticosterone yolk concentrations in stressed quail may represent signals mediating information about adverse environmental conditions from the mother to progeny.

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.

The effects of kale (Brassica oleracea ssp. acephala), basil (Ocimum basilicum) and thyme (Thymus vulgaris) as forage material in organic egg production on egg quality.

PubMed

Hammershøj, M; Steenfeldt, S

2012-01-01

1. In organic egg production, forage material as part of the diet for laying hens is mandatory. The purpose of the present study was to examine the effect of feeding with forage materials including maize silage, herbs or kale on egg production and various egg quality parameters of the shell, yolk colour, egg albumen, sensory properties, fatty acid and carotenoid composition of the egg yolk. 2. A total of 5 dietary treatments were tested for 5 weeks, consisting of a basal organic feed plus 120 g/hen.d of the following forage materials: 1) maize silage (control), 2) maize silage incl. 15 g/kg basil, 3) maize silage incl. 30 g/kg basil, 4) maize silage incl. 15 g/kg thyme, or 5) fresh kale leaves. Each was supplied to three replicates of 20 hens. A total of 300 hens was used. 3. Feed intake, forage intake and laying rate did not differ with treatment, but egg weight and egg mass produced increased significantly with the kale treatment. 4. The egg shell strength tended to be higher with the kale treatment, and egg yolk colour was significantly more red with the kale treatment and more yellow with basil and kale treatments. The albumen DM content and albumen gel strength were lowest with the thyme treatment. By sensory evaluation, the kale treatment resulted in eggs with less sulphur aroma, higher yolk colour score, and more sweet and less watery albumen taste. Furthermore, the eggs of the kale treatment had significantly higher lutein and β-carotene content. Also, violaxanthin, an orange xanthophyll, tended to be higher in kale and eggs from hens receiving kale. 5. In conclusion, forage material, especially basil and kale, resulted in increased egg production and eggs of high and differentiable quality.

Breeding of tomorrow's chickens to improve well-being.

PubMed

Cheng, H-W

2010-04-01

Chickens, as well as other animals, have the ability to change their behavior (behavioral plasticity) and physiology (physiological plasticity) based on the costs and benefits to fit their environment (adaptation). Through natural selection, the population preserves and accumulates traits that are beneficial and rejects those that are detrimental in their prevailing environments. The surviving populations are able to contribute more genes associated with beneficial traits for increased fitness to subsequent generations. Natural selection is slow but constant; working over multiple generations, the changes to the population often appear silent or undetectable at a given point in history. Chickens were domesticated from the wild red jungle fowl. The principle of domestication of chickens, as well as other farm animals, by humans is similar to that of natural selection: selecting the best animals with the highest survivability and reproducibility (artificial selection). Compared with natural selection, the process of artificial selection is motivated by human needs and acts more rapidly with more visible results over a short time period. This process has been further accelerated following the development of current breeding programs and the emergence of specialized breeding companies. A laying hen, for example, produces more than 300 hundred eggs a year, whereas a jungle fowl lays 4 to 6 eggs in a year. During the domestication process, chickens retained their capability to adapt to their housing environments, which is usually achieved by genetic changes occurring with each subsequent generation. Genes control the behavioral, physiological, immunological, and psychological responses of animals to stressors, including environmental stimulations. With advances in understanding of genetic mediation of animal physiology and behavior and the discovery of the genome sequences of many species, animal production breeding programs can be improved in both speed and efficiency. Modern chicken breeding programs have the potential to be operated successfully in the breeding of tomorrow's chickens with high production efficiency and optimal welfare, resulting from resistance to stress, disease, or both.

Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms

PubMed Central

Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

2016-01-01

Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova. PMID:27149082

Germline Defects Caused by Smed-boule RNA-Interference Reveal That Egg Capsule Deposition Occurs Independently of Fertilization, Ovulation, Mating, or the Presence of Gametes in Planarian Flatworms.

PubMed

Steiner, Jessica Kathryne; Tasaki, Junichi; Rouhana, Labib

2016-05-01

Few animals are known to lay eggs in the absence of ovulation or copulation, as it is presumably energetically wasteful and subjected to negative selection. Characterization of Smed-boule, a member of the DAZ family of germline RNA-binding proteins, revealed that egg capsule (or capsule) production and deposition occurs independently of the presence of gametes in the planarian flatworm Schmidtea mediterranea. Reduction of Smed-boule expression by RNA-interference (RNAi) causes ablation of spermatogonial stem cells and the inability of ovarian germline stem cells to undergo oogenesis. Although animals subjected to Smed-boule RNAi lose their gametes and become sterile, they continue to lay egg capsules. Production of sterile capsules is even observed in virgin Smed-boule(RNAi) and control planarians maintained in complete isolation, demonstrating that egg production in S. mediterranea occurs independently of ovulation, fertilization, or mating. Evidence suggests that this is a conserved feature amongst Platyhelminthes, and therefore relevant to the pathology and dissemination of parasitic flatworms. These findings demonstrate that Smed-boule functions at different stages during male and female germline stem cell development, and also demonstrate that egg capsule production by planarian flatworms occurs independently of signals produced by mating or ova.

Quantification of antibody (IgY) titers in hen eggs following immunization and their use in detecting cell surface molecules on nitrocellulose membranes.

PubMed

Ruan, Guang-Ping; Ma, Li; Meng, Xiao-Jing; Meng, Min-Jie; Wang, Xiao-Ning; Lin, Ying; Wu, Zheng-Qiang; He, Xiao-Wei; Wang, Ju-Fang; Zhu, Yong

2007-01-01

HLA-A*0201 alpha chain and beta2m were expressed from a prokaryotic system, and after refolding and purification, the alpha chain and beta2m were used to immunize eight laying hens. The titer of egg yolk antibody against alpha chain increased from 10(2) to 10(5.3) The titer of egg yolk antibody against beta2m increased from 10(1) to 10(4.7). The extent of titer increase is similar between the two antigens. An average of 135 mg purified polyclonal antibody (IgY) can be easily obtained from one egg yolk. The use of egg collection rather than serum collection is compatible with modern animal protection regulations. An average of 28 eggs were obtained from a laying hen every month, with a total amount of 3780 mg immunoglobulin extracted from one immunized hen every month, which would be equivalent to 630 mL of serum or 1260 mL of blood per month. Chickens are an optimal host for the production of polyclonal antibodies with high titer and high yield. Purified IgY was labeled with horseradish peroxidase and reacted with PBMC on nitrocellulose membranes indicating that the antibody can bind to the native conformation of class I HLA molecule on PBMC.

Seasonal development of Leptotrombidium akamushi (Acari: Trombiculidae) under field temperatures.

PubMed

Takahashi, M; Morita, K; Tsuji, O; Misumi, H; Otsuji, J; Hori, E; Kawanura, A; Tanaka, H

1995-11-01

Engorged larvae of Leptotrombidium akamushi (Brumpt), a vector of scrub typhus, were reared in small plastic containers placed on the ground and fed fresh eggs of the collembolan Sinella curviseta Brook. Engorged larvae obtained in October developed into deutonymphs through protonymphs approximately 1 mo before winter and became dormant in the cold winter season (approximately 3 mo). Most deutonymphs developed into tritonymphs in April and adults in May. Females began laying eggs in mid-June and the numbers of unfed larvae showed a peak in August. The mites reared from July rapidly developed into adults by August, and laid eggs in September. Larvae were most abundant in October, and adults became dormant in the winter. The same adults laid eggs from early May to late June and, upon hatching, the larval population peaked in early July of the 2nd summer. Most larvae died before the 2nd winter. Eggs hatched approximately 3 wk after oviposition and longevity of unfed larvae was 2 mo. Because of this very short incubation period, L. akamushi larvae occur in the summer, whereas L. pallidum Nagayo, Miyagawa, Mitamura & Tamiya, and L. scutellare Nagayo, Miyagawa, Mitamura, Tamiya & Tenjin occur in the autumn, although 3 species lay eggs from May to August.

Recombinant egg drop syndrome subunit vaccine offers an alternative to virus propagation in duck eggs.

PubMed

Gutter, B; Fingerut, E; Gallili, G; Eliahu, D; Perelman, B; Finger, A; Pitcovski, J

2008-02-01

Egg drop syndrome (EDS) virus vaccines are routinely produced in embryonated duck eggs (Solyom et al., 1982). This procedure poses the risk of dissemination of pathogens, such as avian influenza virus, as the eggs used are not from specific pathogen free birds. To address this problem, the knob and part of the shaft domain of the fibre protein of the EDS virus (termed knob-s) were expressed in Escherichia coli and assessed as a subunit vaccine. A single vaccination with the recombinant protein induced the production of anti-EDS virus antibodies, as detected by haemagglutination inhibition, enzyme-linked immunosorbent assay and virus neutralization tests, for at least 20 weeks. A positive correlation was demonstrated between these three assays. A dose-response assessment showed that the vaccine was effective over the range of 2 to 64 microg protein per dose. Two vaccinations with the recombinant protein, administered before the onset of lay, induced high haemagglutination inhibition antibody titres, comparable with those induced by an inactivated whole-virus vaccine. The vaccine did not have any adverse effects on egg production, quality or weight. The present study has shown that two vaccinations with the recombinant knob-s protein elicited high neutralizing antibody titres that persisted for more than 50 weeks of lay.

Withdrawal times of oxytetracycline and tylosin in eggs of laying hens after oral administration.

PubMed

Muñoz, Rubén; Cornejo, Javiera; Maddaleno, Aldo; Araya-Jordán, Carolina; Iragüen, Daniela; Pizarro, Nicolás; San Martín, Betty

2014-06-01

Antimicrobials administered to laying hens may be distributed into egg white or yolk, indicating the importance of evaluating withdrawal times (WDTs) of the pharmaceutical formulations. In the present study, oxytetracycline and tylosin's WDTs were estimated. The concentration and depletion of these molecules in eggs were linked to their pharmacokinetic and physicochemical properties. Twenty-seven Leghorn hens were used: 12 treated with oxytetracycline, 12 treated with tylosin, and 3 remained as an untreated control group. After completion of therapies, eggs were collected daily and drug concentrations in egg white and yolk were assessed. The yolk was used as the target tissue to evaluate the WDT; the results were 9 and 3 days for oxytetracycline and tylosin, respectively. In particular, oxytetracycline has a good oral bioavailability, a moderate apparent volume of distribution, a molecular weight of 460 g/mol, and is lightly liposoluble. Tylosin, a hydrosoluble compound, with a molecular weight of 916 g/mol, has a low oral bioavailability and a low apparent volume of distribution, too. Present results suggest that the WDTs of the studied antimicrobials are strongly influenced by their oral bioavailability, the distribution, and the molecular weight and solubility, and that these properties also influence the distribution between the egg yolk and white.

Egg production and quality under three housing systems in the tropics.

PubMed

Varguez-Montero, Grissly; Sarmiento-Franco, Luis; Santos-Ricalde, Ronald; Segura-Correa, Jose

2012-02-01

The aim of this study was to evaluate egg production and quality of Rhode Island Red (RIR) laying hens in an outdoor system in the subhumid tropic. Eighty RIR laying hens were measured in two periods and housed randomly under three treatments: outdoor (O), indoor (I) and in conventional cages (C). Egg weight (55.88, 53.76 and 57.16 g, for O, I and C, respectively), food intake/hen/day (138.94, 129.74 and 162.90 g, for O, I and C, respectively) and food efficiency (3.13, 3.22 and 3.96 for O, I and C, respectively) were significantly (P < 0.05) influenced by housing system; however, both egg production and final body weight were not different (P > 0.05). Yolk colour (10.76, 9.94 and 10.08 colour scale, for O, I and C, respectively), albumen weight (92.63, 92.28 and 90.08 g, for O, I and C, respectively) and yolk weight (15.19, 14.61, 15.48 g for O, I and C, respectively) were significantly (P < 0.05) influenced by housing system, but albumen height, Haugh units and egg shell weight remained similar (P > 0.05). Under the conditions of this study, outdoor egg production seems to be a sustainable system comparable to the commercial type based on wired cages.

Evaluation of jojoba meal as a potential supplement in the diet of broiler breeder females during laying.

PubMed

Vermaut, S; De Coninck, K; Bruggeman, V; Onagbesan, O; Flo, G; Cokelaere, M; Decuypere, E

1999-05-01

1. This study was undertaken to investigate whether jojoba meal can be used as a food supplement during the laying period of chickens. 2. The size of eggs laid were smaller and the overall production rate was lower compared to control birds on food without jojoba meal supplementation. Furthermore, both ovary and oviduct weights were lower in jojoba fed birds. 3. This lowering of egg size and production rate was caused by factors present in jojoba which interfere with follicle growth, yolk deposition, progesterone production and the follicular maturation processes, resulting in the ovulation of smaller follicles and a lower ovulation rate.

Characterisation of Reproduction-Associated Genes and Peptides in the Pest Land Snail, Theba pisana.

PubMed

Stewart, Michael J; Wang, Tianfang; Harding, Bradley I; Bose, U; Wyeth, Russell C; Storey, Kenneth B; Cummins, Scott F

2016-01-01

Increased understanding of the molecular components involved in reproduction may assist in understanding the evolutionary adaptations used by animals, including hermaphrodites, to produce offspring and retain a continuation of their lineage. In this study, we focus on the Mediterranean snail, Theba pisana, a hermaphroditic land snail that has become a highly invasive pest species within agricultural areas throughout the world. Our analysis of T. pisana CNS tissue has revealed gene transcripts encoding molluscan reproduction-associated proteins including APGWamide, gonadotropin-releasing hormone (GnRH) and an egg-laying hormone (ELH). ELH isoform 1 (ELH1) is known to be a potent reproductive peptide hormone involved in ovulation and egg-laying in some aquatic molluscs. Two other non-CNS ELH isoforms were also present in T. pisana (Tpi-ELH2 and Tpi-ELH3) within the snail dart sac and mucous glands. Bioactivity of a synthetic ELH1 on sexually mature T. pisana was confirmed through bioassay, with snails showing ELH1-induced egg-laying behaviours, including soil burrowing and oviposition. In summary, this study presents a detailed molecular analysis of reproductive neuropeptide genes in a land snail and provides a foundation for understanding ELH function.

A calcium-channel homologue required for adaptation to dopamine and serotonin in Caenorhabditis elegans.

PubMed

Schafer, W R; Kenyon, C J

1995-05-04

Processing and storage of information by the nervous system requires the ability to modulate the response of excitable cells to neurotransmitter. A simple process of this type, known as adaptation or desensitization, occurs when prolonged stimulation triggers processes that attenuate the response to neurotransmitter. Here we report that the Caenorhabditis elegans gene unc-2 is required for adaptation to two neurotransmitters, dopamine and serotonin. A loss-of-function mutation in unc-2 resulted in failure to adapt either to paralysis by dopamine or to stimulation of egg laying by serotonin. In addition, unc-2 mutants displayed behaviours similar to those induced by serotonin treatment. We found that unc-2 encodes a homologue of a voltage-sensitive calcium-channel alpha-1 subunit. Expression of unc-2 occurs in two types of neurons implicated in the control of egg laying, a behaviour regulated by serotonin. Unc-2 appears to be required in modulatory neurons to downregulate the response of the egg-laying muscles to serotonin. We propose that adaptation to serotonin occurs through activation of an Unc-2-dependent calcium influx, which modulates the postsynaptic response to serotonin, perhaps by inhibiting the release of a potentiating neuropeptide.

Supplementation of laying-hen feed with palm tocos and algae astaxanthin for egg yolk nutrient enrichment.

PubMed

Walker, Laurie A; Wang, Tong; Xin, Hongwei; Dolde, David

2012-02-29

Adding supplements to hen feed can increase egg nutritional value. Astaxanthin, tocotrienols, and tocopherols are potent antioxidants that provide health benefits to humans. We hypothesized that the addition of these nutrients to hen feed would result in an increased nutrient content in egg yolk with minimum changes in functional properties. Laying hens (Hy-Line W-36 breed) were fed four diets with different supplementation levels of palm toco concentrate and algae biomass containing astaxanthin for 8 weeks. Egg yolks were analyzed for physical, chemical, and functional properties. The feed with the highest nutrient concentration was also studied for stability of these antioxidants using the Arrhenius approach. No significant differences were observed in functional properties except for emulsification capacity and sensory characteristics among eggs from different diet treatments. Changes in egg yolk color reached the maximum values at day 8. Incorporation of tocopherols and tocotrienols increased until day 8, astaxanthin incorporation increased until day 10, and all decreased thereafter. Feed nutrients resulted in a dose-response relationship of these compounds in the egg yolk. The transfer efficiency ranged from 0 to 9.9% for tocotrienols and tocopherols and from 7.6 to 14.9% for astaxanthin at their peak values. Results of the Arrhenius accelerated stability study showed significant differences in the shelf life of various nutrients, and these results can be used to properly formulate and store the feed materials.

Contamination of eggs by Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages

USDA-ARS?s Scientific Manuscript database

Both epidemiologic analyses and active disease surveillance confirm an ongoing strong association between human salmonellosis and the prevalence of Salmonella Enteritidis in commercial egg flocks. The majority of human illnesses caused by this pathogen are attributed to the consumption of contaminat...

Microbiological impact of three commercial laying hen housing systems

USDA-ARS?s Scientific Manuscript database

Hen housing for commercial egg production continues to be a societal and regulatory concern. Controlled studies have examined various aspects of egg safety but a comprehensive assessment of commercial hen housing systems in the US has not been conducted. The current study is part of a holistic, mu...

Integrated farm management to prevent Salmonella Enteritidis contamination of eggs

USDA-ARS?s Scientific Manuscript database

Salmonella Enteritidis (SE) in contaminated eggs is a public health hazard which may cause hospitalization or death in the elderly, infants, and individuals with impaired immune systems. Prevention of SE infection of laying hens is an essential first step in reducing SE outbreaks in humans. Multiple...

Polyommatus ripartii : The Biological Basis for the Conservation and the Morphology of the Developmental Stages of a Critically Endangered, Relict Population in Central Europe

PubMed Central

Przybyłowicz, Łukasz

2014-01-01

Abstract Ripart’s Anomalous Blue Polyommatus ripartii (Freyer, 1830) is one of the most seriously endangered butterfly species in central Europe, a small, relict population of which has survived in two localities in Poland. This isolated population is undoubtedly the last and northernmost remnant of a once much wider range in central Europe. P. ripartii is associated with highly xerophilous vegetation on gypsum and calcareous soils. Only active conservation measures can ensure its survival. For these to be successful, however, precise information on the butterfly’s biology, behavior and also its morphology is crucial. The first to do so, this article describes the butterfly’s egg-laying preferences, and specifies the numbers of eggs on a single shoot and their placement on it. A unique behavioral trait of the female—the secretion of oviposition-deterring pheromones—is reported. The preferred plant associations and nectar sources have been investigated, and information on overnight roosts is given. In addition, an exhaustive description of the morphologies of the egg, final instar and pupa, as well as new details of adult behavior are provided. The main conclusion of the this study is that the existence of a stable population in the Nida Region is determined by the presence of large patches of sainfoin, which is both the larval host plant and a source of nectar for the imago. Moreover, stress is laid on the importance of Inula ensifolia L. as the secondary nectaring plant, which may facilitate dispersion among patches of suitable habitat. Finally, the study shows that searching for the easily detected eggs may be the best method for proving the existence of the species in a given locality. PMID:25525109

Glucose feeding during development aggravates the toxicity of the organophosphorus insecticide Monocrotophos in the nematode, Caenorhabditis elegans.

PubMed

Salim, Chinnu; Rajini, P S

2014-05-28

Several studies have demonstrated that high glucose feeding induced oxidative stress and apoptosis thereby affecting growth, fertility, aging and lifespan in Caenorhabditis elegans. Earlier studies from our laboratory had clearly established the propensity of monocrotophos, an OPI to alter the physiological and behavioral responses of C. elegans. The present study was aimed to investigate the effect of monocrotophos (MCP) on physiological/behavioral and biochemical responses in C. elegans that were maintained on high glucose diet. We exposed the worms through development to high glucose diet (2%) and then treated with sublethal concentrations of MCP (0.5, 0.75, 1.5mM). We measured the behavioral responses in terms of locomotion, physiological responses in terms of egg laying, brood size, lifespan; morphological alterations; and biochemical responses including glucose content. The worms exposed from egg stage through development to high glucose diet showed enhanced toxic outcome of MCP in terms of physiological, behavioral and biochemical responses. Our studies showed that C. elegans is a good model to study glucose-OPI interactive neurotoxicity since all the responses could be studied at ease in this organism and the outcome could be well extrapolated to those that one would expect in higher animals. Copyright © 2014 Elsevier Inc. All rights reserved.

Application of video recording technology to improve husbandry and reproduction in the carmine bee-eater (Merops n. nubicus).

PubMed

Ferrie, Gina M; Sky, Christy; Schutz, Paul J; Quinones, Glorieli; Breeding, Shawnlei; Plasse, Chelle; Leighty, Katherine A; Bettinger, Tammie L

2016-01-01

Incorporating technology with research is becoming increasingly important to enhance animal welfare in zoological settings. Video technology is used in the management of avian populations to facilitate efficient information collection on aspects of avian reproduction that are impractical or impossible to obtain through direct observation. Disney's Animal Kingdom(®) maintains a successful breeding colony of Northern carmine bee-eaters. This African species is a cavity nester, making their nesting behavior difficult to study and manage in an ex situ setting. After initial research focused on developing a suitable nesting environment, our goal was to continue developing methods to improve reproductive success and increase likelihood of chicks fledging. We installed infrared bullet cameras in five nest boxes and connected them to a digital video recording system, with data recorded continuously through the breeding season. We then scored and summarized nesting behaviors. Using remote video methods of observation provided much insight into the behavior of the birds in the colony's nest boxes. We observed aggression between birds during the egg-laying period, and therefore immediately removed all of the eggs for artificial incubation which completely eliminated egg breakage. We also used observations of adult feeding behavior to refine chick hand-rearing diet and practices. Although many video recording configurations have been summarized and evaluated in various reviews, we found success with the digital video recorder and infrared cameras described here. Applying emerging technologies to cavity nesting avian species is a necessary addition to improving management in and sustainability of zoo avian populations. © 2015 Wiley Periodicals, Inc.

Parental conflict and blue egg coloration in a seabird

NASA Astrophysics Data System (ADS)

Morales, Judith; Torres, Roxana; Velando, Alberto

2010-02-01

When both parents provide offspring care, equal sharing of costly parental duties may enhance reproductive success. This is crucial for longlived species, where increased parental effort in current reproduction profoundly affects future reproduction. Indication of reproductive value or willingness to invest in reproduction may promote matching responses by mates, thus reducing the conflict over care. In birds with biparental care, blue-green eggshell color may function as a signal of reproductive value that affects parental effort, as predicted by the signaling hypothesis of blue-green eggshell coloration. However, this hypothesis has not been explored during incubation, when the potential stimulus of egg color is present, and has been little studied in longlived birds. We experimentally studied if egg color affected incubation patterns in the blue-footed booby, a longlived species with biparental care and blue eggs. We exchanged fresh eggs between nests of the same laying date and recorded parental incubation effort on the following 4 days. Although egg color did not affect male effort, original eggshell color was correlated with pair matching in incubation. Exchanged eggshell color did not affect incubation patterns. This suggests that biliverdin-based egg coloration reflects female quality features that are associated with pair incubation effort or that blue-footed boobies mate assortatively high-quality pairs incubating more colorful clutches. An intriguing possibility is that egg coloration facilitates an equal sharing of incubation, the signal being functional only during a short period close to laying. Results also suggest that indication of reproductive value reduces the conflict over care.

The relationship between the immune response and susceptibility to Salmonella enterica serovar Enteritidis infection in the laying hen

USDA-ARS?s Scientific Manuscript database

Chicken eggs are one of the main sources of human salmonellosis, with Salmonella enterica serovar Enteritidis the most frequent cause of human non-typhoid salmonellosis. Laying hens colonized with S. Enteritidis generally do not show clinical signs. The bacteria colonize and invade the intestinal ...

Microbiological differences between laying hen strains housed in various production systems.

USDA-ARS?s Scientific Manuscript database

Sister flocks of three strains of laying hens were housed in conventional cage, free range, and cage free production systems. All flocks were located on a single, commercial-style research facility and provided the same dietary and lighting regimens. Once a season, a sample of shell eggs was asept...

Horizontal transmission of Salmonella Enteritidis in experimentally infected laying hens housed in conventional or enriched cages

USDA-ARS?s Scientific Manuscript database

The majority of human illnesses caused by Salmonella Enteritidis are attributed to contaminated eggs, and the prevalence of this pathogen in commercial laying flocks has been identified as a leading epidemiologic risk factor. Flock housing and management systems can affect opportunities for the intr...

The effect of perch availability during pullet rearing and egg laying on musculoskeletal health of caged White Leghorn hens

USDA-ARS?s Scientific Manuscript database

A major skeletal problem of conventionally caged hens is increased susceptibility to osteoporosis mainly due to lack of exercise. Osteoporosis is characterized by a progressive decrease in mineralized structural bone. Whereas considerable attention has been given to enriching laying cages, little r...

Effect of perches on liver health of hens.

PubMed

Jiang, S; Hester, P Y; Hu, J Y; Yan, F F; Dennis, R L; Cheng, H W

2014-07-01

Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 treatments with 9 hens per cage. Treatment 1 hens never had access to perches during their life cycle. Treatment 2 hens had access to perches during the pullet phase only. Treatment 3 hens had access to perches during the laying phase only. Treatment 4 hens always had access to perches. Liver weight, abdominal fat pad weight, BW, liver fat, and circulating alanine transaminase, aspartate transaminase, and adiponectin were determined. Provision of perches during either the rearing or laying phase did not affect liver health in 71-wk-old hens. However, perch access compared with no perch access during the egg laying phase reduced relative fat pad weight. These results suggest that providing perches as a means of stimulating activity reduced abdominal fat deposition in caged hens during the laying period. However, perch access in caged hens was ineffective in reducing fat deposition in the liver and altering enzyme activities related to improved liver function. © 2014 Poultry Science Association Inc.

The Tissue Distribution of Lutein in Laying Hens Fed Lutein Fortified Chlorella and Production of Chicken Eggs Enriched with Lutein.

PubMed

An, Byoung-Ki; Jeon, Jin-Young; Kang, Chang-Won; Kim, Jin-Man; Hwang, Jae-Kwan

2014-01-01

Two experiments were conducted to investigate the dietary effects of conventional or lutein fortified chlorella on lutein absorptions, the tissue distributions and the changes in lutein content of eggs in laying hens. In Exp 1, a total of one hundred and fifty, 70 wk-old Hy-Line brown layers were divided into three groups with five replicates and fed with each experiment diet (control diet, diet with 1% conventional chlorella or lutein fortified chlorella) for 2 wk, respectively. The egg production in groups fed diets containing both chlorella powders were higher than that of the control group (p<0.01). With chlorella supplementations, the yolk color significantly increased, although there were no significant differences in the eggshell qualities. The lutein contents of serum, liver and growing oocytes were greatly increased by feeding conventional or lutein fortified chlorella (p<0.01). In Exp. 2, a total of ninety 60 wk-old Hy-Line brown layers were assigned into three groups with three replicates per group (10 birds per replicate). The birds were fed with one of three experimental diets (0, 0.1 or 0.2% lutein fortified chlorella) for 2 wk, respectively. The egg production was not affected by dietary treatments. The egg weight in the group fed with diet containing 0.2% of lutein fortified chlorella was higher than that of the control (p<0.05). As the dietary chlorella levels increased, the daily egg mass linearly increased, although not significantly. The yolk colors in groups fed diets containing lutein fortified chlorella were dramatically increased as compared to the control (p<0.001). The lutein in chicken eggs significantly increased when fed with 0.2% of lutein fortified chlorella (p<0.01). These results suggested that the dietary lutein derived from chlorella was readily absorbed into the serum and absorbed by the liver with growing oocyte for commercial laying hens. Particularly, the lutein fortified chlorella was a valuable natural source for the production of lutein enriched chicken eggs.

Reproduction and monogamy in captive flock of greater flamingos (Phoenicopterus Roseus).

PubMed

Sandri, Camillo; Sammarini, Carolina; Regaiolli, Barbara; Spiezio, Caterina; Piccirillo, Alessandra

2018-01-01

Due to the great number of greater flamingos in captivity and their long life span, studying their behavior and welfare might be useful to improve the husbandry and breeding of this species in zoos. This study aimed to investigate factors affecting the breeding activity of captive greater flamingos (Phoenicopterus roseus) from 2012 to 2016. To estimate reproductive success, the number of pairs, eggs laid, and hatchlings were recorded. In addition, information on age, egg-laying history of the partners, and pair composition was collected. An increase in the number of pairs, eggs, and hatchlings was reported over the years. For each breeding season, there were pairs who laid more than once, especially in 2014 and 2015. Approximately 50% of pairs were monogamous between consecutive years; however, the percentage dropped gradually when comparing nonconsecutive years. Senescence and previous experience seemed to affect the reproductive success of the study flamingos. In conclusion, different factors can influence the reproduction of greater flamingos in zoos. All these factors are related to nonhuman animal welfare and need to be considered in developing and improving management practices.

Long-term trends in first arrival and first egg laying dates of some migrant and resident bird species in northern Italy

NASA Astrophysics Data System (ADS)

Rubolini, Diego; Ambrosini, Roberto; Caffi, Mario; Brichetti, Pierandrea; Armiraglio, Stefano; Saino, Nicola

2007-08-01

Climate change is affecting the phenology of seasonal events in Europe and the Northern Hemisphere, as shown by several studies of birds’ timing of migration and reproduction. Here, we analyse the long-term (1982-2006) trends of first arrival dates of four long-distance migratory birds [swift ( Apus apus), nightingale ( Luscinia megarhynchos), barn swallow ( Hirundo rustica), and house martin ( Delichon urbicum)] and first egg laying dates of two migrant (swift, barn swallow) and two resident species [starling ( Sturnus vulgaris), Italian sparrow ( Passer italiae)] at a study site in northern Italy. We also addressed the effects of local weather (temperature and precipitation) and a climate index (the North Atlantic Oscillation, NAO) on the interannual variability of phenological events. We found that the swift and the barn swallow significantly advanced both arrival and laying dates, whereas all other species did not show any significant temporal trend in either arrival or laying date. The earlier arrival of swifts was explained by increasing local temperatures in April, whereas this was not the case for arrival dates of swallows and first egg laying dates of both species. In addition, arrival dates of house martins were earlier following high NAO winters, while nightingale arrival was earlier when local spring rainfall was greater. Finally, Italian sparrow onset of reproduction was anticipated by greater spring rainfall, but delayed by high spring NAO anomalies, and swift’s onset of reproduction was anticipated by abundant rainfall prior to reproduction. There were no significant temporal trends in the interval between onset of laying and arrival in either the swift or the barn swallow. Our findings therefore indicate that birds may show idiosyncratic responses to climate variability at different spatial scales, though some species may be adjusting their calendar to rapidly changing climatic conditions.

Effect of prenatal temperature conditioning of laying hen embryos: Hatching, live performance and response to heat and cold stress during laying period.

PubMed

Kamanli, S; Durmuş, I; Yalçın, S; Yıldırım, U; Meral, Ö

2015-07-01

This study was designed to determine the effect of prenatal temperature conditioning on hatching and live performance of laying chickens, and response to heat and cold stress during laying period. A total of 3600 eggs obtained from ATAK-S brown parent stock were incubated at control (37.5°C, CONT-Inc), cyclic low (36.5°C/6h/d from 10 to 18d of incubation, LOW-Inc) or high (38.5°C/6h/d from 10-18d of incubation, HIGH-Inc) incubation temperatures. Hatched chicks per incubation temperature were reared under standard rearing conditions up to 26wk. From 27 to 30wk, hens from each incubation temperature were divided into 3 environmentally controlled rooms and reared at control (20±2°C, CONT-Room), low (12±2°C, COLDS) or high (32±2°C, HEATS) temperatures. Hatching performance, body weight, egg production, and plasma triiodothyronine (T3) and thyroxine (T4) levels and oxidant and antioxidant activities were evaluated. The highest hatchability was for LOW-Inc chicks while HIGH-Inc chick had similar hatchability to CONT-Inc. There was no effect of incubation temperatures on plasma MDA, GSH-Px, activities and T4 concentrations on day of hatch. LOW- Inc chicks had higher SOD activities and T3 concentrations compared to the other groups. Although chick weight was similar among incubation temperature groups, CONT-Inc chicks were heavier than those cyclic incubation temperature groups until 12wk of age. Incubation temperature had no effect on sexual maturity age and weight and egg production of laying hens. From 27 to 30wk, regardless of incubation temperature, HEATS hens lost weight from day 0 to 10, had the highest cloacal temperatures and lowest feed consumption and egg production while COLDS hens had the lowest cloacal temperatures. At day 5, T4 level was higher in LOW-Inc hens at COLDS but it was higher in HIGH-Inc hens at HEATS compared to CONT-Inc. These data may suggest a modification in thyroid activity of hens that were conditioned during the incubation period. Moreover under COLDS condition, SOD production of LOW-Inc hens was higher than those of CONT- and HIGH-Inc hens indicating an induction in antioxidant enzyme activity. Nonetheless, prenatal temperature conditioning of laying hen embryos had no advantage on laying performance of hens under temperature stress conditions. Copyright © 2015 Elsevier Ltd. 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.

Selenium accumulation and loss in mallard eggs

USGS Publications Warehouse

Heinz, G.H.

1993-01-01

Five female mallards (Anas platyrhynchos) that had just started egg laying were first fed a diet containing 15 ppm selenium in the form of selenomethionine for 20 d and then an untreated diet for 20 d. Selenium levels in eggs peaked (to about 13-20 ppm) in about two weeks on the treated diet and leveled off at a low level ( lt 5 ppm) after about 10 d back on the untreated diet. Selenium levels in egg whites responded faster than levels in yolks to the females' consumption of treated and untreated diets.

The nutritional effect of Moringa oleifera fresh leaves as feed supplement on Rhode Island Red hen egg production and quality.

PubMed

Abou-Elezz Fouad Mohammed, Khaled; Sarmiento-Franco, Luis; Santos-Ricalde, Ronald; Solorio-Sanchez, Javier Francisco

2012-06-01

This study aimed to evaluate the potential of Moringa oleifera fresh leaves (MOL) as feed supplement on the performance and egg quality of Rhode Island Red (RIR) hens under the tropical conditions of Yucatan, Mexico. Forty-eight RIR hens were allocated in 12 floor pen replicates each with four birds. Thereafter, the replicates were divided into three groups which were corresponded to ad libitum feed (control), ad libitum feed supplemented with MOL T1 (AL + MOL) and restricted feed amount (20% lower than control) with MOL T2 (RCD + MOL), respectively. T1 (AL + MOL) had higher egg laying rate (71.4% versus 66.6%), higher daily egg mass production (45.4 versus 41.9 g/day), lower feed intake (121.3 versus 127.5 g/day) and better feed conversion ratio (2.8 versus 3.2 g feed:g egg) versus control. T2 / (RCD + MOL) had lower values of body weight, egg laying rate, egg weight and egg mass, and recorded better feed conversion ratio than the control group. The control group recorded a higher percentage of pecked eggs versus T1 and T2 (6.5% versus 1.2% and 2.0 %). Similar intake of MOL (3.1 and 3.4 g DM/day) was recorded in T1 (AL + MOL) and T2 (RCD + MOL). Yolk color was improved significantly in T1 (AL + MOL) than both control and T2 (RCD + MOL), while T2 (RCD + MOL) had eggs with lower yolk and higher albumen percentages than the other two ad libitum groups. The results suggest that MOL could be used successfully as sustainable tropical feed resource for RIR hens.

Influence of sumac (Rhus Coriaria L.) and ginger (Zingiber officinale) on egg yolk fatty acid, cholesterol and blood parameters in laying hens.

PubMed

Gurbuz, Y; Salih, Y G

2017-12-01

The aim of the study was to evaluate the potential effect of different levels of sumac (Rhus coriaria L.) seed powder and ginger (Zingiber officinale) root powder on egg yolk fatty acid composition, blood/yolk cholesterol in laying hen. A total of 63 (ATAK-S: Domestic Turkish Laying Hens) laying hens (average weight: 1470 g each hen, 25-weeks of age) were assigned to seven treatment diets including sumac seed (S) and ginger root powder (G) at 0 g/kg (control), 10 g/kg (S1), 20 g/kg (S2), and 30 g/kg (S3); 10 g/kg (G1), 20 g/kg (G2), or 30 g/kg in rations respectively, for 8 weeks. After a two-week adaptation period to cages, the hens were allocated to 7 groups with 9 replicates of 1 hen in per cage each. The replications were allotted equally into the upper and lower cages to minimize the effects of cage level. In this study, egg yolk cholesterol had a decrease (p <0.05) in supplemented diet( sumac seed and ginger root powder). Fatty acid content in yolk; saturated fatty acid, monounsaturated fatty acids, polyunsaturated fatty acids and rate of n6/n3 were not significant (p <0.05). However, dietary supplementation with sumac and ginger powder reduced and yolk/blood cholesterol concentrations in laying hens. Supplementation of sumac and ginger affected on HDL, there was found a significant effect (p < 0.05) in treatment groups. Moreover, LDL positively decreased in all treatment groups compared with the control group. The findings of this study suggested that feeding sumac and ginger tend to be decreasing cholesterol levels in both yolk and blood on laying hens. It can be concluded that ginger root and sumac seed powder can be used as an effective feed additive to improve fatty acid composition and yolk and blood cholesterol in ATAK-S laying hens. Journal of Animal Physiology and Animal Nutrition © 2017 Blackwell Verlag GmbH.

A discrete stage-structured model of California newt population dynamics during a period of drought.

PubMed

Jones, Marjorie T; Milligan, William R; Kats, Lee B; Vandergon, Thomas L; Honeycutt, Rodney L; Fisher, Robert N; Davis, Courtney L; Lucas, Timothy A

2017-02-07

We introduce a mathematical model for studying the population dynamics under drought of the California newt (Taricha torosa), a species of special concern in the state of California. Since 2012, California has experienced a record-setting drought, and multiple studies predict drought conditions currently underway will persist and even increase in severity. Recent declines and local extinctions of California newt populations in Santa Monica Mountain streams motivate our study of the impact of drought on newt population sizes. Although newts are terrestrial salamanders, they migrate to streams each spring to breed and lay eggs. Since egg and larval stages occur in water, a precipitation deficit due to drought conditions reduces the space for newt egg-laying and the necessary habitat for larval development. To mathematically forecast newt population dynamics, we develop a nonlinear system of discrete equations that includes demographic parameters such as survival rates for newt life stages and egg production, which depend on habitat availability and rainfall. We estimate these demographic parameters using 15 years of stream survey data collected from Cold Creek in Los Angeles County, California, and our model captures the observed decline of the parameterized Cold Creek newt population. Based upon data analysis, we predict how the number of available newt egg-laying sites varies with annual precipitation. Our model allows us to make predictions about how the length and severity of drought can affect the likelihood of persistence and the time to critical endangerment of a local newt population. We predict that sustained severe drought will critically endanger the newt population but that the newt population can rebound if a drought is sufficiently short. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic parameters of feed efficiency traits and their relationships with egg quality traits in laying period of ducks.

PubMed

Zeng, T; Zhang, H; Liu, J; Chen, L; Tian, Y; Shen, J; Lu, L

2018-03-01

The objective of this study was to estimate genetic parameters for feed efficiency and relevant traits in 2 laying duck breeds, and to determine the relationship of residual feed intake (RFI) with feed efficiency and egg quality traits. Phenotypic records on 3,000 female laying ducks (1,500 Shaoxing ducks and 1,500 Jinyun ducks) from a random mating population were used to estimate genetic parameters for RFI, feed conversion ratio (FCR), feed intake (FI), BW, BW gain (BWG), and egg mass laid (EML) at 42 to 46 wk of age. The heritability estimates for EML, FCR, FI, and RFI were 0.22, 0.19, 0.22, and 0.27 in Shaoxing ducks and 0.14, 0.19, 0.24, and 0.24 for Jinyun ducks, respectively. RFI showed high and positive genetic correlations with FCR (0.47 in Shaoxing ducks and 0.63 in Jinyun ducks) and FI (0.79 in Shaoxing ducks and 0.86 in Jinyun ducks). No correlations were found in RFI with BW, BWG, or EML at either genetic or phenotypic level. FCR was strongly and negatively correlated with EML (-0.81 and -0.68) but inconsistently correlated with FI (0.02 and 0.17), suggesting that EML was the main influence on FCR. In addition, no significant differences were found between low RFI (LRFI) and high RFI (HRFI) ducks in egg shape index, shell thickness, shell strength, yolk color, albumen height, or Haugh unit (HU). The results indicate that selection for LRFI could improve feed efficiency and reduce FI without significant changes in EML or egg quality.

A discrete stage-structured model of California newt population dynamics during a period of drought

USGS Publications Warehouse

Jones, Marjorie T.; Milligan, William R.; Kats, Lee B.; Vandergon, Thomas L.; Honeycutt, Rodney L.; Fisher, Robert N.; Davis, Courtney L.; Lucas, Timothy A.

2017-01-01

We introduce a mathematical model for studying the population dynamics under drought of the California newt (Taricha torosa), a species of special concern in the state of California. Since 2012, California has experienced a record-setting drought, and multiple studies predict drought conditions currently underway will persist and even increase in severity. Recent declines and local extinctions of California newt populations in Santa Monica Mountain streams motivate our study of the impact of drought on newt population sizes. Although newts are terrestrial salamanders, they migrate to streams each spring to breed and lay eggs. Since egg and larval stages occur in water, a precipitation deficit due to drought conditions reduces the space for newt egg-laying and the necessary habitat for larval development. To mathematically forecast newt population dynamics, we develop a nonlinear system of discrete equations that includes demographic parameters such as survival rates for newt life stages and egg production, which depend on habitat availability and rainfall. We estimate these demographic parameters using 15 years of stream survey data collected from Cold Creek in Los Angeles County, California, and our model captures the observed decline of the parameterized Cold Creek newt population. Based upon data analysis, we predict how the number of available newt egg-laying sites varies with annual precipitation. Our model allows us to make predictions about how the length and severity of drought can affect the likelihood of persistence and the time to critical endangerment of a local newt population. We predict that sustained severe drought will critically endanger the newt population but that the newt population can rebound if a drought is sufficiently short.

Passive immunization with hyperimmune egg yolk IgY as prophylaxis and therapy for poultry diseases---A review

USDA-ARS?s Scientific Manuscript database

Passive immunization with pathogen-specific egg yolk antibodies (IgY) is emerging as a potential alternative to antibiotics for the treatment and prevention of various human and animal diseases. Laying hens are an excellent source of high-quality polyclonal antibodies, which can be collected noninv...

Nutritional quality of eggs from hens fed distillers dried grains with solubles

USDA-ARS?s Scientific Manuscript database

A feeding trial was conducted with laying hens where either 10% or 20% regular-fat distiller’s dried grains with solubles (R-DDGS) or low-fat DDGS (L-DDGS) were incorporated into the feed. Production parameters and the effect of DDGS on egg nutritional quality, focusing on yolk lipids, were evaluate...

Position statement on the provision and procurement of human eggs for stem cell research.

PubMed

Haimes, Erica; Skene, Loane; Ballantyne, Angela J; Caulfield, Timothy; Goldstein, Lawrence S; Hyun, Insoo; Kimmelman, Jonathan; Robert, Jason S; Roxland, Beth E; Scott, Christopher T; Solbakk, Jan Helge; Sugarman, Jeremy; Taylor, Patrick L; Testa, Giuseppe

2013-03-07

The nature of compensation for women who donate eggs (oocytes) for research remains a contentious issue internationally. This position paper lays out the arguments for, and discusses the arrangements in which, a modest payment might be ethically justifiable. Copyright © 2013 Elsevier Inc. All rights reserved.

Growth enhancement of rainbow trout (Oncorhynchus mykiss) by passive immunisation against somatostatin-14

USDA-ARS?s Scientific Manuscript database

Juvenile rainbow trout (Oncorhynchus mykiss) were passively immunised against somatostatin-14 (SS-14) using an antibody originating from egg laying chicken (Gallus domesticus). Fish were immunised weekly (0, 7, 14, 21, 28, 35 d) with chicken egg yolk derived immunoglobulin (IgY) against SS-14 (1:25 ...

9 CFR 592.2 - Terms defined.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., respectively: Act means the applicable provisions of the Agricultural Marketing Act of 1946 (60 Stat. 1087; 7 U... geographical area. Eggs of Current Production means shell eggs that have moved through the usual marketing channels since the date of lay and are not in excess of 60 days old. Holiday or Legal holiday means the...

Persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in conventional or enriched cages

USDA-ARS?s Scientific Manuscript database

: Because Salmonella Enteritidis can be deposited inside eggs laid by infected hens, the prevalence of this pathogen in commercial egg-producing flocks is an important risk factor for human illness. Opportunities for the introduction, transmission, and persistence of salmonellae in poultry are poten...

Persistence of fecal shedding of Salmonella Enteritidis by experimentally infected laying hens housed in conventional or enriched cages.

USDA-ARS?s Scientific Manuscript database

Because Salmonella Enteritidis can be deposited inside eggs laid by infected hens, the prevalence of this pathogen in commercial egg-producing flocks is an important risk factor for human illness. Opportunities for the introduction, transmission, and persistence of salmonellae in poultry are potenti...

The Coalition for Sustainable Egg Supply: A unique public-private partnership for conducting research on the sustainability of animal housing systems using a multistakeholder approach.

PubMed

Mench, J A; Swanson, J C; Arnot, C

2016-03-01

The growing emphasis on ensuring the sustainability of animal agriculture is providing an impetus for the adoption of new approaches to structuring and conducting research. Sustainability is a complex topic involving many considerations related to the economic, social, and environmental impacts of production systems. Successfully addressing this topic requires multidisciplinary research as well as a high degree of communication with food system stakeholders to ensure that the research results contribute to informed decision making. In this paper, we provide an overview of a public-private partnership, the Coalition for Sustainable Egg Supply (CSES), which was formed to support research evaluating the sustainability of laying hen housing systems. Because of increasing public concerns about the behavioral restriction imposed on laying hens housed in conventional cages, the U.S. egg industry is faced with a need to transition to alternative systems. However, before the CSES project, there was limited information available about how this transition might affect trade-offs related to the sustainability of egg production. The goal of the CSES project was to provide this information by conducting holistic research on a commercial farm that had 3 different hen housing systems. The CSES members represented a variety of stakeholders, including food retailers and distributors, egg producers, universities, and governmental (USDA ARS) and nongovernmental organizations. The CSES was facilitated by a not-for-profit intermediary, the Center for Food Integrity, which was also responsible for communicating the research results to food system stakeholders, including via quantitative and qualitative consumer research. In this paper, we describe the structural aspects of the CSES that were responsible for the successful completion and dissemination of the research as well as the insights that were gained regarding multidisciplinary and multi-institutional collaboration, conducting commercial-scale research, fostering and maintaining stakeholder interaction, and communicating research results. Although not without limitations, this project demonstrates that public-private partnerships can be effective strategies for addressing sustainability questions related to animal agriculture and, thus, serves as a useful model for the other animal industries.

House Wrens adjust laying dates and clutch size in relation to annual flooding

Treesearch

Deborah M. Finch

1991-01-01

I examined timing of reproduction and productivity in box-nesting House Wrens (Troglodytes aedon) inhabiting three riverbank woodlands subjected to different levels of flooding. In years when the North Platte River flooded its banks submerging ground foraging substrates, dates of nest initiation and egg laying in two wren populations were delayed and nonsynchronized....

Sustainability of egg production in the United States--the policy and market context.

PubMed

Mench, J A; Sumner, D A; Rosen-Molina, J T

2011-01-01

The US egg industry is being pressured from many directions to change its production practices, particularly to address concerns about hen welfare in conventional cage systems. Responding to similar pressures, in 1999, the European Union banned conventional laying cages starting in 2012. This now impending European ban has led to the development of several alternative housing systems. These include noncage systems like aviaries and modified (enriched or furnished) cages that include perches, areas in which the hens can forage and dustbathe, and nests. Understanding the European experience is valuable as the United States considers the future direction of the egg industry. In the United States, the proportion of eggs produced in alternative systems is small (less than 5% of output) but growing, in part due to market and political incentives for systems that provide hens with more behavioral freedom than conventional cages. Animal welfare, however, is only one element of a sustainable production system. Other elements include those related to public values, the environment, economics, worker health, and food safety and quality. Eggs are a primary source of animal protein globally, and the United States is the third largest producer of eggs in the world, behind China and the European Union. The national table egg flock comprises about 280 million hens housed in all regions but with approximately 60% of eggs produced in the 10 leading states. Adopting new housing systems will have substantial effects on costs and other aspects of egg production on both a regional and national scale, with some positive effects but also potential negative effects that need to be carefully considered. This paper discusses the US egg industry in the context of legislation and standards related to hen housing systems. It also addresses initiatives by retailers, nongovernmental organizations, and private certification organizations to shape production practices in the egg industry as well as how those initiatives might affect various aspects of the sustainability of egg production.

Development of furnished cages for laying hens.

PubMed

Appleby, M C; Walker, A W; Nicol, C J; Lindberg, A C; Freire, R; Hughes, B O; Elson, H A

2002-09-01

1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in front rollaway nests. Dust baths were used more for pecking and scratching than for dust bathing. Comfort behaviour was more frequent in furnished cages than conventional, although still not frequent. Locomotion was strongly affected by number of birds per cage or by space per bird, being reduced by crowding. Most birds perched at night except in one treatment providing only 10.7 cm perch per bird. 7. Behaviour was more unrestricted and varied, and physical condition was better, in furnished than in conventional cages. However, egg production will cost more in furnished cages, partly because more eggs are downgraded. Dust baths must be fitted with gates that the birds cannot open from outside, but gates for nest boxes were found unnecessary. If a low perch is fitted it must be far enough from the back of the cage for birds to walk there. 8. Where there was less space per bird (more birds per cage) than the requirements in the 1999 European Commission Directive on laying hens, there were: fewer eggs per hen, but still above the breeders' target; lower food consumption; more feather and foot damage, but less than in conventional cages; higher mortality in one trial out of three; less freedom of movement. However, the results were still very good even with 8 birds per cage, and support the principle that furnished cages provide an acceptable way of protecting the welfare of laying hens.

Effects of dietary cottonseed meal and iron-treated cottonseed meal in different laying hen genotypes.

PubMed

Panigrahi, S; Morris, T R

1991-03-01

The effects of dietary screw-pressed cottonseed meal (CSM) and iron-treated CSM on laying performance and discolourations in eggs were examined in a range of hen genotypes. In experiment 1, six genotypes, obtained at point-of-lay from various sources, were fed on a non-CSM diet, a diet with 300 g CSM/kg, and a diet containing iron-treated CSM at 300 g/kg. In experiment 2, two of these genotypes were reared together from day-old and were fed from 10 to 18 weeks on a non-CSM diet or a diet containing iron-treated CSM at 250 g/kg. They were then fed on a non-CSM layer diet or a diet containing iron-treated CSM at 300 g/kg, in a 2 x 2 x 2 factorial design that also examined the effects of the rearing diet. 2. The effects on food intakes and egg production of including CSM and iron-treated CSM in layer diets depended on the genotype of the hens. The strongest interaction between breed and diet was on food intake, the breed Hubbard Golden Comet (HGC) being the least tolerant of CSM and iron-treated CSM. 3. Inclusion of iron-treated CSM in the rearer diet to supply approximately 70% of the dietary protein had no adverse effects on growth or age at first egg. Food intake and egg production between 18 and 26 weeks were affected by the iron-treated CSM layer diet, but there were no carry-over effects attributable to the rearing diets. 4. Genotype was not a factor in the development of the gossypol-related brown yolk discolouration in fresh or warm-stored eggs of hens fed on a CSM-based diet containing 197 mg free gossypol/kg and 52 mg cyclopropenoid fatty acids (CPFA)/kg (experiment 1). 5. In both experiments, the susceptibility of eggs to the CPFA-related cold storage effects depended on the genotype of the hen, eggs from hens of the HCG breed being more affected than those of ISA hens. 6. Treatment of CSM with crystalline ferrous sulphate heptahydrate, at a 4:1 weight ratio of iron to free gossypol, prevented brown yolk discolourations in all genotypes tested, as assessed by subjecting egg yolks to atmospheres of ammonia, and cold storage of eggs.

Response of laying hens to feeding low-protein amino acid-supplemented diets under high ambient temperature: performance, egg quality, leukocyte profile, blood lipids, and excreta pH

NASA Astrophysics Data System (ADS)

Torki, Mehran; Mohebbifar, Ahmad; Ghasemi, Hossein Ali; Zardast, Afshin

2015-05-01

An experiment was conducted to determine whether, by using a low-protein amino acid-supplemented diet, the health status, stress response, and excreta quality could be improved without affecting the productive performance of heat-stressed laying hens. The requirements for egg production, egg mass, and feed conversion ratio were also estimated using second-order equations and broken-line regression. A total of 150 Lohmann Selected Leghorn (LSL-Lite) hens were divided randomly into five groups of 30 with five replicates of six hens. The hens were raised for an 8-week period (52 to 60 weeks) in wire cages situated in high ambient temperature in an open-sided housing system. The five experimental diets (ME; 2,720 kcal/kg) varied according to five crude protein (CP) levels: normal-CP diet (control, 16.5 % CP) and low-CP diets containing 15.0, 13.5, 12.0, or 10.5 % CP. All experimental diets were supplemented with crystalline amino acids at the levels sufficient to meet their requirements. The results showed that under high temperature conditions, all productive performance and egg quality parameters in the birds fed with 15.0, 13.5, and 12.0 % CP diets were similar to those of birds fed with control diet (16.5 % CP), whereas feeding 10.5 % CP diet significantly decreased egg production and egg mass. Estimations of requirements were of 13.93 and 12.77 % CP for egg production, 14.62 and 13.22 % CP for egg mass, and 12.93 and 12.26 % CP for feed conversion ratio using quadratic and broken-line models, respectively. Egg yolk color index, blood triglyceride level, and excreta acidity were also significantly higher in birds fed with 12.0 and 10.5 % CP diets compared with those of control birds. The heterophil to lymphocyte ratio, as a stress indicator, was significantly decreased by 15.0, 13.5, and 12 % CP diets. On the basis of our findings, reducing dietary CP from 16.5 to 12.0 % and supplementing the diets with the essential amino acids showed merit for improving the stress response and excreta quality while maintaining acceptable production performance from laying hens under high ambient temperature conditions.

Inhibited Oviposition by Females of Gryllus assimilis (F.), induced by Radioactive Males, using L-Methionine-Methyl- 14C

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

ABDEL-MALEK, A. A.; KEVAN, D. K. McE.

1961-11-18

Results of matings between radioactive and normal or non-radioactive individuals of Gryllus assimilis (North American field crickets) are reported. The treatment of males with L-methionine-methyl-carbon-l4 caused inhibition of egg-laying females and sterility of the male itself. This inhibited oviposition applies to both radioactive and normal virgin females when they are mated with radioactive males. However, if the female is mated with a normal male no effect is noticed in normal oviposition whether the female is normal or radioactive. As a matter of fact, it appears that the radioactive female lays more eggs when mated with a normal male. (N.W.R.)

Egg production and welfare of laying hens kept in different housing systems (conventional, enriched cage, and free range).

PubMed

Yilmaz Dikmen, B; İpek, A; Şahan, Ü; Petek, M; Sözcü, A

2016-07-01

The aim of this study was to compare egg production performance and welfare traits of laying hens kept in conventional cage (CC), enriched cage (EC), and free range (FR). Lohmann Brown laying hens (n = 480 with 160 per housing type) were studied across a production cycle from placement at 17 wk until depopulation at 66 wk. The hens were randomly allocated into cages or pens of housing system groups; within each system there were four replicates with 40 hens in each pen or cage. The hen day egg production (P = 0.037), feed intake (FI) (P < 0.001), egg mass (EM) (P < 0.001), and dirty egg ratio of hens were higher in the FR system but similar in the CC and EC systems. The highest mortality ratio was found in EC system hens (P = 0.020). The best feather score was found in FR system hens (P < 0.001). The worse body wound score was found in EC system hens (P = 0.038). On the other hand, the worse bumble foot and footpad lesions were found in FR system hens (P < 0.001). The highest tibia breaking strength was found in FR system hens compared with in CC and EC system hens (P < 0.001). The highest Heterophil/Lymphocyte ( H/L: ) ratio was found in CC system hens (P = 0.006) but the blood phosphorus ( P: ) level was higher in FR system hens (P = 0.013). The tonic immobility, blood glucose, total cholesterol, triglyceride, and Ca values of hens were found to be similar in all systems (P > 0.05). The hens in the FR system had additional space for optimum comfort and better feather and bone traits, but the dirty egg ratio, feed consumption, and foot lesions were higher than in CC and EC systems. © 2016 Poultry Science Association Inc.

Effect of light-emitting diode vs. fluorescent lighting on laying hens in aviary hen houses: Part 1 - Operational characteristics of lights and production traits of hens.

PubMed

Long, H; Zhao, Y; Wang, T; Ning, Z; Xin, H

2016-01-01

Light-emitting diode (LED) lights are becoming more affordable for agricultural applications. Despite many lab-scale studies concerning impact of LED on poultry, little research has been documented under field production conditions, especially for laying hens. This 15-month field study was carried out to evaluate the effects of LED vs. fluorescent (FL) lights on laying hens (Dekalb white breed) using 4 (2 pairs) aviary hen houses each at a nominal capacity of 50,000 hens. The evaluation was done regarding operational characteristics of the lights and hen production traits. The results show that spatial distribution of the LED light was less uniform than that of the FL light. Light intensity of the LED light decreased by 27% after 3,360 h use but remained quite steady from 3,360 to 5,760 h use. Eleven out of 762 (1.44%) LED lamps (new at onset of the study) in the 2 houses failed during the 15-month experiment period. The neck area of the LED lamp was hottest, presumably the primary reason for the lamp failure as cracks were noticed in the neck region of all failed LED lamps. No differences were observed in egg weight, hen-day egg production, feed use, and mortality rate between LED and FL regimens. However, hens under the FL had higher eggs per hen housed and better feed conversion than those under the LED during 20 to 70 wk production (P < 0.05). Hens under the LED tended to have less feather uniformity and insulation than those under the FL (P < 0.05). Moreover, hens under the LED showed a larger median avoidance distance than those under the FL at 36 wk age (P < 0.05), indicating that hens under the LED were more alert; but no difference at 60 wk age. More comparative research to quantify behavioral and production responses of different breeds of hens to LED vs. FL lighting seems warranted. © 2015 Poultry Science Association Inc.

Breeding productivity and survival of the endangered Hawai'i Creeper in a wet forest refuge on Mauna Kea, Hawai'i

USGS Publications Warehouse

Collins, Mark

2001-01-01

We studied the demography of the endangered Hawai‘i Creeper (Oreomystis muna) from 1994-1999 at three sites in Hakalau Forest National Wildlife Refuge (NWR). Hawai‘i Creepers bred from January to June, with peak breeding in February through May (about 120-l 80 days), and molted from May to August. A small proportion (4.9%) of individuals overlapped breeding and molting activities. We located and monitored the fates of 60 nests. Mean clutch size was 2.1 eggs, nest building required 19 days, incubation was 16 to 17 days, and nestling period lasted 18 days. Of all nest attempts, 25% were abandoned before egg laying, 6.7% were removed for captive propagation, 13.3% had undetermined fates, 38.3% failed during incubation or nestling periods, and 16.7% were successful. Thus, of 33 nests that were active through egg laying and outcome was confirmed, only 30% were successful. The daily survival rate of active nests was 0.960 t 0.009 SE. An average of 1.7 chicks fledged from successful nests. Thirty-two percent of hatch-year birds were alive and in the study area at least one year later. Annual adult survival was high (0.88 t 0.03). The primary factors limiting productivity of Hawai‘i Creeper in Hakalau Forest NWR appear to be low reproductive potential in combination with high rates of nesting failure. Further research into the causes of nest failure, the length of the breeding season, and renesting behavior of females is needed, and protection of the forest from the degrading impacts of introduced mammals is paramount.

USSR Report: Agriculture. No. 1393.

DTIC Science & Technology

1983-07-27

production of meat by 106 percent, milk by 150 percent, eggs by 103 percent, grain by 119 percent and potatoes by 126 percent. We are proud of the...Woman I. Ugleva who obtained 262 eggs from each laying hen, as compared to a planned 225. The army and navy has increased the number of military...18,500 tons of milk, and 7.5 million eggs . In other words, their contribution to improving the food situation is appreciable. Today, many private

Trio’s Rho-specific GEF domain is the missing Gαq effector in C. elegans

PubMed Central

Williams, Stacey L.; Lutz, Susanne; Charlie, Nicole K.; Vettel, Christiane; Ailion, Michael; Coco, Cassandra; Tesmer, John J.G.; Jorgensen, Erik M.; Wieland, Thomas; Miller, Kenneth G.

2007-01-01

The Gαq pathway is essential for animal life and is a central pathway for driving locomotion, egg laying, and growth in Caenorhabditis elegans, where it exerts its effects through EGL-8 (phospholipase Cβ [PLCβ]) and at least one other effector. To find the missing effector, we performed forward genetic screens to suppress the slow growth and hyperactive behaviors of mutants with an overactive Gαq pathway. Four suppressor mutations disrupted the Rho-specific guanine-nucleotide exchange factor (GEF) domain of UNC-73 (Trio). The mutations produce defects in neuronal function, but not neuronal development, that cause sluggish locomotion similar to animals lacking EGL-8 (PLCβ). Strains containing null mutations in both EGL-8 (PLCβ) and UNC-73 (Trio RhoGEF) have strong synthetic phenotypes that phenocopy the arrested growth and near-complete paralysis of Gαq-null mutants. Using cell-based and biochemical assays, we show that activated C. elegans Gαq synergizes with Trio RhoGEF to activate RhoA. Activated Gαq and Trio RhoGEF appear to be part of a signaling complex, because they coimmunoprecipitate when expressed together in cells. Our results show that Trio’s Rho-specific GEF domain is a major Gαq effector that, together with PLCβ, mediates the Gαq signaling that drives the locomotion, egg laying, and growth of the animal. PMID:17942708

Anti-amyloid compounds protect from silica nanoparticle-induced neurotoxicity in the nematode C. elegans

PubMed Central

Scharf, Andrea; Gührs, Karl-Heinz; von Mikecz, Anna

2016-01-01

Abstract Identifying nanomaterial-bio-interactions are imperative due to the broad introduction of nanoparticle (NP) applications and their distribution. Here, we demonstrate that silica NPs effect widespread protein aggregation in the soil nematode Caenorhabditis elegans ranging from induction of amyloid in nucleoli of intestinal cells to facilitation of protein aggregation in body wall muscles and axons of neural cells. Proteomic screening revealed that exposure of adult C. elegans with silica NPs promotes segregation of proteins belonging to the gene ontology (GO) group of “protein folding, proteolysis and stress response” to an SDS-resistant aggregome network. Candidate proteins in this group include chaperones, heat shock proteins and subunits of the 26S proteasome which are all decisively involved in protein homeostasis. The pathway of protein homeostasis was validated as a major target of silica NPs by behavioral phenotyping, as inhibitors of amyloid formation rescued NP-induced defects of locomotory patterns and egg laying. The analysis of a reporter worm for serotonergic neural cells revealed that silica NP-induced protein aggregation likewise occurs in axons of HSN neurons, where presynaptic accumulation of serotonin, e.g. disturbed axonal transport reduces the capacity for neurotransmission and egg laying. The results suggest that in C. elegans silica NPs promote a cascade of events including disturbance of protein homeostasis, widespread protein aggregation and inhibition of serotonergic neurotransmission which can be interrupted by compounds preventing amyloid fibrillation. PMID:26444998

Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines.

PubMed

Hussain, Ashiq; Zhang, Mo; Üçpunar, Habibe K; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C

2016-05-01

The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly's high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans.

Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines

PubMed Central

Üçpunar, Habibe K.; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C.

2016-01-01

The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly’s high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans. PMID:27145030

Overwintering Stages of Meloidogyne incognita in Vitis vinifera.

PubMed

Melakeberhan, H; Ferris, H; McKenry, M V; Gaspard, J T

1989-01-01

The overwintering of Meloidogyne incognita in and around Vitis vinifera cv. French Colombard roots was studied in a naturally infested vineyard at the Kearney Agricultural Center, in a growth chamber, in inoculated vines in microplots at the University of California, Davis, and in a greenhouse. Infected roots were sampled at intervals from onset of vine dormancy until plants accumulated about 800 degree days (DD - base 10 C). Embryogenesis within eggs, classified as less than or more than 16 cells and fully differentiated, and numbers of juveniles (second to fourth stage) and preovipositional and mature (egg-laying) adult stages in roots were determined. All stages were present at the onset of dormancy. Juveniles and immature females were not recovered during the dormant period. Mature females and eggs were always present in roots, although the number of mature females generally decreased with time after onset of dormancy. In contrast, in a greenhouse experiment that accumulated comparable DD without the host plant going through dormancy, the number of mature females increased. After bud break, the number of eggs per female increased and all nematode stages were found in host roots. Eggs in all stages of embryogenesis were observed at all times of sampling, indicating that females overwinter and are capable of laying eggs when conditions improve in the spring and need to be considered in nematode management decisions.

Effect of supplementation of the laying hen diet with olive leaves (Olea europea L.) on lipid oxidation and fatty acid profile of α-linolenic acid enriched eggs during storage.

PubMed

Botsoglou, E; Govaris, A; Fletouris, D; Botsoglou, N

2012-01-01

1. The aim of this study was to evaluate the effect of supplementation of the layer diet with olive leaves (Olea europea L.) on lipid oxidation and fatty acid profile of α-linolenic acid enriched eggs during refrigerated storage, and to compare this effect with α-tocopheryl acetate supplementation. 2. A total of 72 brown Lohmann laying hens, equally allocated to 3 groups, were fed on diets supplemented with 40 g/kg linseed oil, or linseed oil and olive leaves at 10 g/kg or linseed oil and α-tocopheryl acetate at 200 mg/kg. Collected eggs were analysed for fatty acid profile and lipid oxidation either fresh or following 60 d storage at 4°C. 3. Results showed that olive leaves or α-tocopheryl acetate supplementation reduced lipid hydroperoxide concentration in fresh eggs but had no effect on their fatty acid profile and malondialdehyde (MDA) content compared to controls. 4. Refrigerated storage for 60 d decreased the proportions of PUFAs but increased those of MUFAs in eggs from the control diet, whilst it had no effect on the fatty acid composition of eggs from the diets supplemented with olive leaves or α-tocopheryl acetate, which in turn showed decreased concentrations of lipid hydroperoxides and MDA.

Individual variation in body burden, lipid status, and reproductive investment is related to maternal transfer of a brominated diphenyl ether (BDE-99) to eggs in the zebra finch.

PubMed

Eng, Margaret L; Elliott, John E; Letcher, Robert J; Williams, Tony D

2013-02-01

Avian eggs are exposed to hydrophobic contaminants through maternal transfer. How maternal transfer of contaminants within a species is influenced by individual variation in characteristics such as body burden, yolk precursor levels, or reproductive investment is not understood. The authors investigated sources of variation in the maternal transfer of 2,2',4,4',5-pentabromodiphenyl ether (BDE-99) in zebra finches (Taeniopygia guttata). The authors dosed adult female zebra finches with levels of BDE-99 relevant to exposure in wild birds (0, 33.7 or 173.8 ng/g body wt/d) for three weeks prior to pairing. Maternal BDE-99 and very-low-density lipoprotein (VLDL) in plasma were measured during egg formation and at clutch completion, and BDE-99 was measured in the corresponding egg. The lipid-normalized egg-to-maternal tissue BDE-99 relationship decreased with increasing maternal burden. Individual variation in maternal VLDL was related to BDE-99 transfer to the eggs when BDE-99 was at background levels in control birds, but not when BDE-99 was elevated in dosed birds. The decrease in maternal plasma BDE-99 over the laying period was only significant (p < 0.05) in the high-dose birds. Finally, the decrease in BDE-99 in maternal plasma during egg-laying was significantly positively correlated with clutch mass in the high-dose group. These results suggest that the relationship between maternal and egg contaminant levels can be highly variable. This has significant implications for using eggs as indicators of adult or environmental concentrations. Copyright © 2012 SETAC.

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.

Peptidoglycan sensing by octopaminergic neurons modulates Drosophila oviposition

PubMed Central

Kurz, C Leopold; Charroux, Bernard; Chaduli, Delphine; Viallat-Lieutaud, Annelise; Royet, Julien

2017-01-01

As infectious diseases pose a threat to host integrity, eukaryotes have evolved mechanisms to eliminate pathogens. In addition to develop strategies reducing infection, animals can engage in behaviors that lower the impact of the infection. The molecular mechanisms by which microbes impact host behavior are not well understood. We demonstrate that bacterial infection of Drosophila females reduces oviposition and that peptidoglycan, the component that activates Drosophila antibacterial response, is also the elicitor of this behavioral change. We show that peptidoglycan regulates egg-laying rate by activating NF-κB signaling pathway in octopaminergic neurons and that, a dedicated peptidoglycan degrading enzyme acts in these neurons to buffer this behavioral response. This study shows that a unique ligand and signaling cascade are used in immune cells to mount an immune response and in neurons to control fly behavior following infection. This may represent a case of behavioral immunity. DOI: http://dx.doi.org/10.7554/eLife.21937.001 PMID:28264763

Effects of inositol, inositol-generating phytase B applied alone, and in combination with 6-phytase A to phosphorus-deficient diets on laying performance, eggshell quality, yolk cholesterol, and fatty acid deposition in laying hens.

PubMed

Zyla, K; Mika, M; Duliński, R; Swiatkiewicz, S; Koreleski, J; Pustkowiak, H; Piironen, J

2012-08-01

Phytase B, a product of Aspergillus niger phyB gene expressed in Trichoderma reesei, which increased myo-inositol concentrations in 20 mM sodium phytate solution 7.5-fold during 120-min incubation, a combination of phytase B with 6-phytase A, and pure myo-inositol were tested as feed supplements in Bovans Brown laying hens. In the 2-factorial experiment (2×5), birds from wk 50 to 62 were fed 2 basal diets, corn-soybean (CSM) or wheat-soybean (WSM), using 12 one-hen cages per treatment. For both basal diets, the dietary treatments included negative control (0.08% nonphytate P in CSM, 0.13% nonphytate P in WSM; NC); internal control groups, NC+0.04% nonphytate P from monocalcium phosphate, MCP (IC); NC+0.1% of myo-inositol (Inos), NC+phytase B at 1,300 units of phytase B-acid phosphatase activity (AcPU)/kg (PhyB), NC+phytase B at 1,300 AcPU/kg+6-phytase A at 300 FTU/kg (PhyA+B). Feed intake, laying performance, and eggshell quality were determined. The total lipid and cholesterol contents as well as fatty acid profile were assessed in egg yolks collected from hens fed CSM diets, as was fatty acid profile. The hens fed the WSM diet consumed significantly more feed, laid a higher mass of eggs daily with higher mean weights, and had a higher hen-day egg production than the birds receiving the CSM diets. Similarly, higher values for yolk weights, shell weights, shell thickness, shell density, and breaking strengths were determined in the eggs laid by the hens fed the WSM diets. In hens fed either the CSM diets with phytase B alone, or in combination with 6-phytase A, enhanced feed intakes, egg mass, and hen-day egg production were recorded. Phytases also enhanced the eggshell quality parameters in the hens fed both variants of the diets. Phytase B alone, or in combination with 6-phytase A, reduced the total lipid and cholesterol concentrations in egg yolks collected from the hens fed the CSM diets, whereas the combination of both phytases improved the n-6:n-3 polyunsaturated fatty acids ratio. In the CSM diets, the supplemental myo-inositol suppressed feed intakes, reduced egg production, had no effect on eggshell quality and reduced the deposition of eicosanoid fatty acids in yolks. When comparing the effects of feeding MCP, myo-inositol, and phytases on the nutritional quality of the eggs laid by the hens fed phosphorus-deficient CSM diets, it seems that the enhancements in nutritional quality cannot be attributed solely to higher phosphorus level or higher concentrations of myo-inositol.

Reducing the maladaptive attractiveness of solar panels to polarotactic insects.

PubMed

Horváth, Gábor; Blahó, Miklós; Egri, Adám; Kriska, György; Seres, István; Robertson, Bruce

2010-12-01

Human-made objects (e.g., buildings with glass surfaces) can reflect horizontally polarized light so strongly that they appear to aquatic insects to be bodies of water. Insects that lay eggs in water are especially attracted to such structures because these insects use horizontal polarization of light off bodies of water to find egg-laying sites. Thus, these sources of polarized light can become ecological traps associated with reproductive failure and mortality in organisms that are attracted to them and by extension with rapid population declines or collapse. Solar panels are a new source of polarized light pollution. Using imaging polarimetry, we measured the reflection-polarization characteristics of different solar panels and in multiple-choice experiments in the field we tested their attractiveness to mayflies, caddis flies, dolichopodids, and tabanids. At the Brewster angle, solar panels polarized reflected light almost completely (degree of polarization d ≈ 100%) and substantially exceeded typical polarization values for water (d ≈ 30-70%). Mayflies (Ephemeroptera), stoneflies (Trichoptera), dolichopodid dipterans, and tabanid flies (Tabanidae) were the most attracted to solar panels and exhibited oviposition behavior above solar panels more often than above surfaces with lower degrees of polarization (including water), but in general they avoided solar cells with nonpolarizing white borders and white grates. The highly and horizontally polarizing surfaces that had nonpolarizing, white cell borders were 10- to 26-fold less attractive to insects than the same panels without white partitions. Although solar panels can act as ecological traps, fragmenting their solar-active area does lessen their attractiveness to polarotactic insects. The design of solar panels and collectors and their placement relative to aquatic habitats will likely affect populations of aquatic insects that use polarized light as a behavioral cue. © 2010 Society for Conservation Biology.

Effect of golden needle mushroom (Flammulina velutipes) stem waste on laying performance, calcium utilization, immune response and serum immunity at early phase of production.

PubMed

Mahfuz, Shad; Song, Hui; Liu, Zhongjun; Liu, Xinyu; Diao, Zipeng; Ren, Guihong; Guo, Zhixin; Cui, Yan

2018-05-01

This experiment was conducted to evaluate the effects of golden needle mushroom ( Flammulina velutipes ) stem waste (FVW), on organic eggs production, calcium utilization, antibody response, serum immunoglobulin, and serum cytokine concentration at early phase of production in laying hens. A total 210, 19 weeks old aged ISA Brown layers were randomly assigned into 5 equal treatment groups, with 7 replications of 6 hens each. Dietary treatment included a standard basal diet as control; antibiotic (0.05% flavomycin); 2% FVW; 4% FVW; and 6% FVW. The experimental duration was 10 weeks. There was no significant differences (p>0.05) on hen day egg production, egg weight, egg mass, feed intake, and feed conversion ratio (FCR) among experimental groups. Unmarketable eggs were significantly lower (p<0.05) both in 4% FVW and 6% FVW fed groups than control group. The calcium retention and calcium in egg shell deposition were significantly higher (p<0.05) in FVW inclusion groups than control and antibiotic groups. Antibody titers against Newcastle diseases were significantly higher (p<0.05) in 6% FVW fed group (except combined with 4% FVW at day 147) and infectious bronchitis were significantly higher (p< 0.05) in FVW fed groups (except 2% FVW and 4% FVW at day 161) than control and antibiotic groups. Serum immunoglobulin sIgA was significantly higher (p<0.05) in all levels of FVW and IgG was significantly higher (p<0.05) in 4% FVW than control and antibiotic groups. Serum cytokine concentration interleukin-2 (IL-2) was significantly higher (p<0.05) in 6% FVW; IL-6 and tumor necrotic factor-α were significantly higher (p<0.05) both in 4% FVW and 6% FVW than control and antibiotic groups; IL-4 was significantly higher (p<0.05) in antibiotic, 2% FVW and 4% FVW fed groups than control. F. velutipes mushroom waste can be used as a novel substitute for antibiotic for organic egg production and sound health status in laying hens.

Effect of dietary vanadium and vitamin C on egg quality and antioxidant status in laying hens.

PubMed

Wang, J P; He, K R; Ding, X M; Luo, Y H; Bai, S P; Zeng, Q F; Su, Z W; Xuan, Y; Zhang, K Y

2016-06-01

This study assessed the effect of dietary vanadium (V) and vitamin C (VC) on production performance, egg quality and antioxidant status in laying hens. A total of 360 laying hens (31-week-old) were randomly allotted into a 3 × 3 factorial arrangement treatments (four replicates and 10 chicks per replicate) with three levels of dietary V (0, 5 and 10 mg/kg) and three levels of vitamin C (0, 50 and 100 mg/kg) for 12 weeks. The effect of V and VC did not alter egg production, egg weight, average daily feed intake and feed conversion ratio during 1-12 week. Albumen height and Haugh unit value were linearly decreased (p < 0.001) by addition of V, whereas the effect of 100 mg/kg VC was observed to counteract (p < 0.05) this effect in V-containing treatments during 1-12 week. Hens fed V-containing diet laid lighter (linear effect, p < 0.05) coloured eggs (higher lightness value, lower redness and yellowness value), and the VC exerted no influence on it during 1-12 week. The serum superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities, ability to inhibit hydroxyl radical, were significantly decreased, and the malondialdehyde (MDA) and V contents were increased (p < 0.05) by effect of V during 4, 8 and 12 week. The effect of VC alone and the interactive effect between VC and V were shown to increase serum (p < 0.05) SOD activity in 4 week and decrease MAD levels in 12 week. The result indicate that V decreased the egg quality and caused the oxidative stress at level of 5 mg/kg and 10 mg/kg, and the addition of 100 mg/kg vitamin C can alleviate its egg quality reduction effect and can mitigate the oxidative stress to some extent. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

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

Life history of Milnesium tardigradum Doyère (tardigrada) under a rearing environment.

PubMed

Suzuki, Atsushi C

2003-01-01

A strain of carnivorous tardigrade, Milnesium tardigradum, was reared in water on agar plates at 25 degrees C. The monogonont rotifer Lecane inermis was presented as a food source. This rearing system permitted detailed observation of tardigrade behaviour. Daily measurements of body length allowed the growth rate and moulting cycle of this species to be determined. The life history of M. tardigradum raised under these conditions included up to seven periods of moult. The first and second moults occurred at intervals of 4-5 days, and individuals reached reproductive maturity at the 3rd-instar stage; the first period of egg laying accompanied the third moult. The most rapidly developing animal in the study population laid eggs 12 days after hatching. The egg-laying intervals or moulting intervals of adult animals were around 6-10 days. The mean clutch size was 6.9 eggs. All tardigrades in this laboratory population were female and reproduced by parthenogenesis. The duration of the embryonic stage ranged from 5-16 days. The most long-lived female survived for 58 days after hatching, and laid a total of 41 eggs in 5 separate clutches. The entire life cycle of tardigrades reared under these conditions was recorded and photographed. A brief description of the embryonic development of M. tardigradum was also reported.

Productivity and some properties of egg yolk antibody (IgY) against human rotavirus compared with rabbit IgG.

PubMed

Hatta, H; Tsuda, K; Akachi, S; Kim, M; Yamamoto, T

1993-03-01

Productivity and some properties of anti-Human Rotavirus (HRV) hen egg yolk antibody (IgY) were compared with those of anti-HRV rabbit serum antibody (IgG). The hens immunized with HRV (Wa strain, serotype 1 and Mo strain, serotype 3) were found to continuously to lay eggs without any change in the egg laying rate and the yolk of the eggs laid over a year showed a high level of neutralization titer against HRV. The production of anti-HRV IgY by a hen (one year) was at least 15 times (anti-Wa) and 120 times (anti-Mo) more effective than those by an immunized rabbit in the neutralization titer of the antibodies. The stability of anti-HRV IgY at temperature above 70 degrees C and low pH 2-3 was less than that of anti-HRV rabbit IgG. The temperature corresponding to the maximum of denaturation endotherm (Tmax) of IgY was 73.9 degrees C while that of rabbit IgG was 77.0 degrees C in the analysis by differential scanning calorimetry. This discrepancy in heat and acidic pH stability found between the two antibodies as discussed with regard to their protein structures.

Effect of dietary karaya saponin on serum and egg yolk cholesterol in laying hens.

PubMed

Afrose, S; Hossain, M S; Tsujii, H

2010-12-01

1. The objective of the study was to investigate the effect of dietary karaya saponin on cholesterol deposition in laying hens. 2. A total of 40 Boris Brown hens were randomly assigned at 20 weeks of age to 4 treatment groups and fed on diets supplemented with 0 (control), 25, 50 or 75 mg/kg karaya saponin for an 8-week experimental period. 3. After 8 weeks of dietary supplementation, karaya-saponin-treated groups had significantly lower serum cholesterol (23·0%) and triglycerides but increased high density lipoproteins cholesterol concentration than controls, irrespective of karaya saponin content in the diet. Egg yolk cholesterol and triglycerides were also significantly reduced by dietary karaya saponin. Hepatic cholesterol and triglycerides were significantly reduced by karaya saponin but bile acids concentration in the faeces and liver were significantly increased by karaya saponin. The concentrations of oleic, linoleic and linolenic acids in the yolk were greater in hens receiving karaya saponin than in controls. Karaya saponin significantly increased egg production, feed efficiency and yolk colour compared with controls. Karaya saponin tended to increase egg weight, feed consumption, Haugh units, albumen weight and yolk index. 4. In conclusion, karaya saponin is a potential agent for reducing yolk cholesterol concentration together with an overall increase of production performance and improvement in egg quality.

Isolation and characterization of a Chinese strain of Tembusu virus from Hy-Line Brown layers with acute egg-drop syndrome in Fujian, China.

PubMed

Chen, Shilong; Wang, Shao; Li, Zhaolong; Lin, Fengqiang; Cheng, Xiaoxia; Zhu, Xiaoli; Wang, Jingxiang; Chen, Shaoying; Huang, Meiqing; Zheng, Min

2014-05-01

Tembusu virus (TMUV) has been a causative agent of an acute egg-drop syndrome found in Chinese duck populations since at least 2010. In this paper, we report the characterization of a TMUV-like flavivirus (named CJD05) isolated from naturally infected egg-laying fowl. The virus was identified and then isolated from hens suffering from severe egg drop and fever in Fujian Province, China. The virus replicated well in MDEF and CEF cells, and its cytopathogenic effect (CPE) was apparent. Hemagglutinating activity (HA) was negative for this virus using erythrocytes from both chickens and pigeons. Viral particles were enveloped and approximately 45 nm in diameter, as observed by electron microscopy. Phylogenetic analysis of the full-length nucleotide sequence of CJD05 indicated that this virus is closely related to the duck-origin TMUV, belonging to Ntaya group of flavivirus. Most importantly, pathogenicity studies showed that CJD05 is highly virulent in 1-day-old chicks, 1-day-old Muscovy ducks, egg-laying chickens and shelducks. Our research highlights the increase in epidemic disease caused by avian TMUV, and subsequent outbreaks are becoming more complicated to treat. The pathogenic mechanisms of the virus are still not fully understood, further research is needed.

A comparison of the breeding ecology of birds nesting in boxes and tree cavities

Treesearch

Kathryn L. Purcell; Jared Verner; Lewis W. Oring

1997-01-01

We compared laying date, nesting success, clutch size, and productivity of four bird species that nest in boxes and tree cavities to examine whether data from nest boxes are comparable with data from tree cavities. Western Bluebirds (Sialia mexicana) gained the most advantage from nesting in boxes. They initiated egg laying earlier, had higher nesting success, lower...

Feeding ecology of breeding gadwalls on saline wetlands

USGS Publications Warehouse

Serie, J.R.; Swanson, G.A.

1976-01-01

The feeding ecology of breeding gadwalls (Anas strepera) from saline wetlands in North Dakota was examined in relation to sex, pair mates, reproductive status, food availability, and wetland type during the spring and summer of 1971 and 1972. Esophagi of males and females contained 40.4 and 48.2 percent animal food, respectively, between 17 April and 25 August. Animal foods consumed by paired females varied with reproductive condition and were independent of their mates. Invertebrates increased from 47.7 i?? 17.4 percent in the diet during prelaying to 72.0 i?? 18.4 percent during laying and declined to 46.3 i?? 30.0 percent during postlaying. Aquatic insects dominated the diet during egg-laying and were selected disproportionately relative to their availability. Esophageal contents indicated that diversity of plant and animal foods in the diet varied inversely with specific conductance. Major factors influencing food selection of the breeding birds are discussed as interactions among their physiological status, their anatomical and behavioral characteristics, and the abundance and behavior of food organisms as influenced by chemical and physical features of the environment. The data suggested that these interrelated ecological factors act simultaneously to control the phenology of events and determine the foods utilized.

Infectious bronchitis virus and brown shell colour: Australian strains of infectious bronchitis virus affect brown eggshell colour in commercial laying hens differently.

PubMed

Samiullah, Sami; Roberts, Juliet; Chousalkar, Kapil

2016-10-01

The aim of the current study was to assess any effect of wild and vaccine Australian infectious bronchitis virus (IBV) strains on shell colour in brown-shelled eggs. In Experiment 1, eggs were collected from day 1 to day 13 post-inoculation (p.i.) from unvaccinated laying hens challenged with IBV wild strains T and N1/88 and from a negative control group of hens. In Experiment 2, eggs were collected from 2 to 22 days p.i. from unvaccinated and vaccinated laying hens challenged with either a wild or a vaccine strain of IBV. In Experiment 1, there was a significant effect (P < 0.05) of day p.i. and of viral strain on shell reflectivity, L* and protoporphyrin IX (PP IX) in eggshells, with and without cuticle. The mean PP IX/g of shell with and without cuticle was significantly higher on day 1 p.i. compared to day 7, after which PP IX increased with day p.i. In Experiment 2, shell reflectivity and L* increased and PP IX decreased with increased day p.i. until day 12. Shell reflectivity and L* decreased slightly after day 12 and increased again towards day 22. Shell reflectivity, L* and PP IX were not significantly different for eggshells from unvaccinated and vaccinated laying hens in the intact eggshell, but were significantly different in shells from which cuticle had been removed. In conclusion, the IBV strains reduced the intensity of brown shell colour to different extents with a lower amount of PP IX in eggshells.

Cryptic gentes revealed in pallid cuckoos Cuculus pallidus using reflectance spectrophotometry

PubMed Central

Starling, M; Heinsohn, R; Cockburn, A; Langmore, N.E

2006-01-01

Many cuckoo species lay eggs that match those of their hosts, which can significantly reduce rejection of their eggs by the host species. However, egg mimicry is problematic for generalist cuckoos that parasitize several host species with different egg types. Some generalist cuckoos have overcome this problem by evolving several host-specific races (gentes), each with its own, host-specific egg type. It is unknown how generalist cuckoos lacking gentes are able to avoid egg rejection by hosts. Here we use reflectance spectrophotometry (300–700 nm) on museum egg collections to test for host-specific egg types in an Australian generalist cuckoo reported to have a single egg type. We show that the colour of pallid cuckoo (Cuculus pallidus) eggs differed between four host species, and that their eggs closely mimicked the eggs of the host they parasitized. These results reveal that pallid cuckoos have host-specific egg types that have not been detected by human observation, and indicate that gentes could be more common than previously realized. PMID:16822754

Conservation of Bio synthetic pheromone pathways in honeybees Apis

NASA Astrophysics Data System (ADS)

Martin, Stephen J.; Jones, Graeme R.

Social insects use complex chemical communication systems to govern many aspects of their life. We studied chemical changes in Dufour's gland secretions associated with ovary development in several genotypes of honeybees. We found that C28-C38 esters were associated only with cavity nesting honeybee queens, while the alcohol eicosenol was associated only with their non-laying workers. In contrast, both egg-laying anarchistic workers and all parasitic Cape workers from queenright colonies showed the typical queen pattern (i.e. esters present and eicosenol absent), while egg-laying wild-type and anarchistic workers in queenless colonies showed an intermediate pattern, producing both esters and eicosenol but at intermediate levels. Furthermore, neither esters nor eicosenol were found in aerial nesting honeybee species. Both esters and eicosenol are biosynthetically similar compounds since both are recognizable products of fatty acid biosynthesis. Therefore, we propose that in honeybees the biosynthesis of esters and eicosenol in the Dufour's gland is caste-regulated and this pathway has been conserved over evolutionary time.

Dimorphic ejaculates and sperm release strategies associated with alternative mating behaviors in the squid.

PubMed

Apostólico, Lígia H; Marian, José E A R

2017-11-01

Sperm competition is a powerful postcopulatory selective force influencing male adaptations associated with increasing fertilization success, and it is usually related to the evolution of different strategies of ejaculate expenditure between individuals. Ejaculates may also be influenced by additional selective pressures associated with sperm competition, such as timing between insemination and fertilization, female reproductive tract morphology, and fertilization environment. Also, males that adopt alternative mating tactics may face distinct sperm competition pressures, which may lead to the evolution of intraspecific diversity in ejaculates. In loliginid squids, males with alternative reproductive tactics (sneakers and consorts) differ not only in mating behavior, but also transfer spermatophores into two distinct sites within the female. Here, we compared structure and functioning of spermatophores between sneakers and consorts in the squid Doryteuthis plei applying microscopy techniques and in vitro experiments. Sneakers and consorts exhibit differences in spermatophore structure that lead to distinct spermatophoric reactions and spermatangium morphologies. Moreover, in sneakers, sperm release lasts longer and their sperm show an aggregative behavior not detected in consorts. Slow sperm release may be a strategy to guarantee longer sperm provision, given the wide interval between sneaker mating and egg release. For consorts, in turn, intense and quick sperm discharge may be advantageous, as timing between mating and egg-laying is relatively short. Within the complex squid mating system, factors such as (i) different fertilization sites and (ii) interval between mating and egg release may also influence sperm competition, and ultimately shape the evolution of divergent ejaculates between dimorphic males. © 2017 Wiley Periodicals, Inc.

Increased expression of a cGMP-dependent protein kinase in rotation-adapted western corn rootworm (Diabrotica virgifera virgifera L.).

PubMed

Garabagi, Freydoun; Wade French, B; Schaafsma, Arthur W; Peter Pauls, K

2008-07-01

A new 'variant' behavior in western corn rootworm (WCR) has resulted in egg-laying into non-cornfields, compared to 'normal' deposition of eggs in cornfields, allowing these insects to circumvent crop rotation. No morphological or genetic characteristics have been defined to differentiate between the normal and variant biotypes. Cyclic GMP-dependent protein kinases (PKG) have been implicated in the regulation of behaviors in vertebrates, insects, and nematodes, including foraging behavior in Drosophila. A cDNA with homology to the Drosophila melanogaster foraging gene (called Dvfor1) was cloned from WCR. The deduced DvFOR1 protein is approximately 70% similar to FOR proteins in Drosophila, silkworm (Bombyx mori) and honeybee (Apis mellifera). It contains a coiled-coil region, two tandem cyclic nucleotide-binding domains, a serine/threonine kinase catalytic domain, and a serine/threonine kinase catalytic domain extension, which are all characteristically found in PKG proteins. Real-time PCR assays of foraging transcript levels in heads of normal and rotation adapted females of WCR obtained from lab-reared insect colonies indicated that the variants had higher levels (25%) of PKG expression than normals. The magnitude of this increase is similar to that observed in Drosophila rover phenotypes compared to sitter phenotypes. However, Diabrotica contains at least two different foraging gene transcripts, which complicates establishing a direct link between the level of gene expression and insect behavior.

Genetic parameters and principal component analysis for egg production from White Leghorn hens.

PubMed

Venturini, G C; Savegnago, R P; Nunes, B N; Ledur, M C; Schmidt, G S; El Faro, L; Munari, D P

2013-09-01

The objectives of this study were to estimate genetic parameters for accumulated egg production over 3-wk periods and for total egg production over 54 wk of egg-laying, and using principal component analysis (PCA), to explore the relationships among the breeding values of these traits to identify the possible genetic relationships present among them and hence to observe which of them could be used as selection criteria for improving egg production. Egg production was measured among 1,512 females of a line of White Leghorn laying hens. The traits analyzed were the number of eggs produced over partial periods of 3 wk, thus totaling 18 partial periods (P1 to P18), and the total number of eggs produced over the period between the 17 and 70 wk of age (PTOT), thus totaling 54 wk of egg production. Estimates of genetic parameters were obtained by means of the restricted maximum likelihood method, using 2-trait animal models. The PCA was done using the breeding values of partial and total egg production. The heritability estimates ranged from 0.05 ± 0.03 (P1 and P8) to 0.27 ± 0.06 (P4) in the 2-trait analysis. The genetic correlations between PTOT and partial periods ranged from 0.19 ± 0.31 (P1) to 1.00 ± 0.05 (P10, P11, and P12). Despite the high genetic correlation, selection of birds based on P10, P11, and P12 did not result in an increase in PTOT because of the low heritability estimates for these periods (0.06 ± 0.03, 0.12 ± 0.04, and 0.10 ± 0.04, respectively). The PCA showed that egg production can be divided genetically into 4 periods, and that P1 and P2 are independent and have little genetic association with the other periods.

Effect of nutrient density on production performance, egg quality and humoral immune response of brown laying (Dahlem Red) hens in the tropics.

PubMed

Panda, Arun Kumar; Rao, Savaram Venkata Rama; Raju, Mantena Venkata Lakshmi Narasimha; Niranjan, Matam; Reddy, Maddula Ramkoti

2012-02-01

A study was conducted to evaluate the effect of various concentrations of metabolizable energy (ME) with graded incremental levels of crude protein (CP) and essential amino acids (lysine and methionine) on production performance, egg quality and humoral immune response of Dahlem Red laying hens. Four experimental diets based on maize-soybean meal-deoiled rice bran were prepared. Diet 1 was fed as a control diet containing 2,600 kcal ME/kg, 15% CP, 0.75% Lys and 0.36% Met, and in the other three diets (D2, D3 and D4), concentrations of the above nutrients were increased by 2.5%, 5.0% and 7.5%, respectively. The levels of Ca (3.5%) and available P (0.32) were constant in all the diets. Each diet was offered ad libitum from 28 to 40 weeks of age to eight replicates containing six birds in each replicate. The egg production, egg weight and egg mass (in grams of egg per hen per day) were not affected by increasing the nutrient density up to 7.5% (2,795 kcal ME/kg diet) compared to the control group (2,600 ME/kg diet). However, feed consumption and feed efficiency (in grams of egg per gram of feed) were influenced by the variation in the nutrient density of diets. As the nutrient density increased by 5% (2,730 ME/kg diet), birds consumed significantly (P < 0.001) less feed. The birds in the 7.5% higher density group produced significantly (P < 0.05) higher egg mass per unit feed consumption compared to the control diet. Increasing nutrient density up to 7.5% had no effect on relative weight of albumen, yolk or shell. The Haugh unit, yolk colour and shell thickness were also not affected due to variation in the nutrient density. The humoral immune response measured at 34 and 40 weeks was progressively improved by increasing the nutrient density up to 5%. Increasing the nutrient density beyond 5% in the diet had no further influence on the humoral immune response. Based on the results of the present study, it can be concluded that Dahlem Red laying hens required 2,795 kcal/kg ME, 16% CP, 0.8% lysine and 0.4% methionine for eliciting optimum performance and immune response during 28 to 40 weeks of age.

Adult fruit fly attraction to larvae biases experience and mediates social learning.

PubMed

Durisko, Zachary; Anderson, Blake; Dukas, Reuven

2014-04-01

We investigated whether adult fruit flies (Drosophila melanogaster) use cues of larvae as social information in their food patch choice decisions. Adult male and female fruit flies showed attraction to odours emanating from foraging larvae, and females preferred to lay eggs on food patches occupied by larvae over similar unoccupied patches. Females learned and subsequently preferred to lay eggs at patches with novel flavours previously associated with feeding larvae over patches with novel flavours previously associated with no larvae. However, when we controlled for the duration of exposure to each flavoured patch, females no longer preferred the flavour previously associated with feeding larvae. This suggests that social learning in this context is indirect, as a result of strong social attraction biasing experience.

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development

PubMed Central

Erickson, Gregory M.; Zelenitsky, Darla K.; Kay, David Ian; Norell, Mark A.

2017-01-01

Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11–85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growth-line counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous–Paleogene mass extinction event. PMID:28049837

Dinosaur incubation periods directly determined from growth-line counts in embryonic teeth show reptilian-grade development.

PubMed

Erickson, Gregory M; Zelenitsky, Darla K; Kay, David Ian; Norell, Mark A

2017-01-17

Birds stand out from other egg-laying amniotes by producing relatively small numbers of large eggs with very short incubation periods (average 11-85 d). This aspect promotes high survivorship by limiting exposure to predation and environmental perturbation, allows for larger more fit young, and facilitates rapid attainment of adult size. Birds are living dinosaurs; their rapid development has been considered to reflect the primitive dinosaurian condition. Here, nonavian dinosaurian incubation periods in both small and large ornithischian taxa are empirically determined through growth-line counts in embryonic teeth. Our results show unexpectedly slow incubation (2.8 and 5.8 mo) like those of outgroup reptiles. Developmental and physiological constraints would have rendered tooth formation and incubation inherently slow in other dinosaur lineages and basal birds. The capacity to determine incubation periods in extinct egg-laying amniotes has implications for dinosaurian embryology, life history strategies, and survivorship across the Cretaceous-Paleogene mass extinction event.

Prevalence of Dermanyssus gallinae (Mesostigmata: Dermanyssidae) in industrial poultry farms in North-East Tunisia

PubMed Central

Gharbi, Mohamed; Sakly, Nadhem; Darghouth, Mohamed Aziz

2013-01-01

Dermanyssus gallinae (Mesostigmata: Dermanyssidae), a mite of poultry, represents the most important ecotoparasite of egg-laying poultry in several countries. We estimated the prevalence of D. gallinae infestation in 38 industrial poultry farms (28 egg-laying and 10 reproductive hen farms) in the governorate of Nabeul (North-East Tunisia). Traps were placed in two locations of each farm during 24 h in August. The overall prevalence at the farms was estimated to be 34%. A total number of 329 D. gallinae were collected, giving an intensity of 0.0028 and an abundance of 0.0015. Infestation intensity and abundance were significantly higher in egg production farms than reproductive farms. There was no correlation between the intensity of infestation and temperature. An exponential correlation was observed between the birds’ age and infestation intensity. We recommend a systematic survey of poultry farms during the whole breeding period. Prompt treatment is recommended to avoid the exponential increase of mite population. PMID:24160169

Prevalence of Dermanyssus gallinae (Mesostigmata: Dermanyssidae) in industrial poultry farms in North-East Tunisia.

PubMed

Gharbi, Mohamed; Sakly, Nadhem; Darghouth, Mohamed Aziz

2013-01-01

Dermanyssus gallinae (Mesostigmata: Dermanyssidae), a mite of poultry, represents the most important ecotoparasite of egg-laying poultry in several countries. We estimated the prevalence of D. gallinae infestation in 38 industrial poultry farms (28 egg-laying and 10 reproductive hen farms) in the governorate of Nabeul (North-East Tunisia). Traps were placed in two locations of each farm during 24 h in August. The overall prevalence at the farms was estimated to be 34%. A total number of 329 D. gallinae were collected, giving an intensity of 0.0028 and an abundance of 0.0015. Infestation intensity and abundance were significantly higher in egg production farms than reproductive farms. There was no correlation between the intensity of infestation and temperature. An exponential correlation was observed between the birds' age and infestation intensity. We recommend a systematic survey of poultry farms during the whole breeding period. Prompt treatment is recommended to avoid the exponential increase of mite population. © M. Gharbi et al., published by EDP Sciences, 2013.

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.

Female gonadal hormones and reproductive behaviors as key determinants of successful reproductive output of breeding whooping cranes (Grus americana)

USGS Publications Warehouse

Brown, Megan E; Converse, Sarah J.; Chandler, Jane N.; Shafer, Charles; Brown, Janine L; Keefer, Carol L; Songsasen, Nucharin

2016-01-01

Reproductive success of endangered whooping cranes (Grus americana) maintained ex situ is poor. As part of an effort to identify potential causes of poor reproductive success in a captive colony, we used non-invasive endocrine monitoring to assess gonadal and adrenal steroids of bird pairs with various reproductive outcomes and evaluated the relationships of hormones and behaviors to reproductive performance. Overall, reproductively successful (i.e., egg laying) females had significantly higher mean estrogen levels but lower mean progestogen concentrations than did unsuccessful females. Other hormones, including glucocorticoids and androgens, were not significantly different between successful and unsuccessful individuals. Observations of specific behaviors such as unison calling, marching, and the number of copulation attempts, along with overall time spent performing reproductive behaviors, were significantly higher in successful pairs. Our findings indicate that overall reproductive performance of whooping crane pairs is linked to female gonadal hormone excretion and reproductive behaviors, but not to altered adrenal hormone production.

Female gonadal hormones and reproductive behaviors as key determinants of successful reproductive output of breeding whooping cranes (Grus americana).

PubMed

Brown, Megan E; Converse, Sarah J; Chandler, Jane N; Shafer, Charles; Brown, Janine L; Keefer, Carol L; Songsasen, Nucharin

2016-05-01

Reproductive success of endangered whooping cranes (Grus americana) maintained ex situ is poor. As part of an effort to identify potential causes of poor reproductive success in a captive colony, we used non-invasive endocrine monitoring to assess gonadal and adrenal steroids of bird pairs with various reproductive outcomes and evaluated the relationships of hormones and behaviors to reproductive performance. Overall, reproductively successful (i.e., egg laying) females had significantly higher mean estrogen levels but lower mean progestogen concentrations than did unsuccessful females. Other hormones, including glucocorticoids and androgens, were not significantly different between successful and unsuccessful individuals. Observations of specific behaviors such as unison calling, marching, and the number of copulation attempts, along with overall time spent performing reproductive behaviors, were significantly higher in successful pairs. Our findings indicate that overall reproductive performance of whooping crane pairs is linked to female gonadal hormone excretion and reproductive behaviors, but not to altered adrenal hormone production. Published by Elsevier Inc.

The effect of perches in cages during pullet rearing and egg laying on hen performance, foot health, and plumage

USDA-ARS?s Scientific Manuscript database

Our objective was to determine if perch availability during all or part of the life cycle of caged Hy-Line W-36 chickens affected egg traits, foot health, and feather condition. Using a 2 x 2 factorial arrangement, treatment 1 represented control chickens which never had access to perches during the...

Status of ash (Fraxinus spp.) species in Alabama, Arkansas, Mississippi, and Louisiana, 2013

Treesearch

S.N. Oswalt

2015-01-01

The emerald ash borer (EAB; Agrilus planipennis) is an introduced Asian beetle species that was first detected in trees in the Fraxinus (ash) genus in the United States in 2002. Female EAB beetles lay between 40 to 70 eggs in cracks, crevices, and beneath bark flakes. The eggs hatch within about 2 weeks, larvae bore through the...

Biofortified orange maize enhances β-cryptoxanthin concentrations in egg yolks of laying hens better than tangerine peel fortificant.

PubMed

Heying, Emily K; Tanumihardjo, Jacob P; Vasic, Vedran; Cook, Mark; Palacios-Rojas, Natalia; Tanumihardjo, Sherry A

2014-12-10

The xanthophyll β-cryptoxanthin provides vitamin A and has other purported health benefits. Laying hens deposit xanthophyll carotenoids into egg yolk. Hens (n = 8/group) were fed conventional-bred high β-cryptoxanthin biofortified (orange) maize, tangerine peel-fortified white maize, lutein-fortified yellow maize, or white maize for 40 d to investigate yolk color changes using L*a*b* scales, yolk carotenoid enhancement, and hen vitamin A status. Yolks from hens fed orange maize had scores indicating a darker, orange color and mean higher β-cryptoxanthin, zeaxanthin, and β-carotene concentrations (8.43 ± 1.82, 23.1 ± 4.8, 0.16 ± 0.08 nmol/g, respectively) than other treatments (P < 0.0001). Yolk retinol concentrations (mean: 14.4 ± 3.42 nmol/g) were similar among groups and decreased with time (P < 0.0001). Hens fed orange maize had higher liver retinol (0.53 ± 0.20 μmol/g liver) than other groups (P < 0.0001). β-Cryptoxanthin-biofortified eggs could be another choice for consumers, providing enhanced color through a provitamin A carotenoid and supporting eggs' status as a functional food.

Reproductive physiology

USGS Publications Warehouse

Gee, G.F.; Russman, S.E.; Ellis, David H.; Gee, George F.; Mirande, Claire M.

1996-01-01

Conclusions: Although the general pattern of avian physiology applies to cranes, we have identified many physiological mechanisms (e.g., effects of disturbance) that need further study. Studies with cranes are expensive compared to those done with domestic fowl because of the crane's larger size, low reproductive rate, and delayed sexual maturity. To summarize, the crane reproductive system is composed of physiological and anatomical elements whose function is controlled by an integrated neural-endocrine system. Males generally produce semen at a younger age than when females lay eggs. Eggs are laid in clutches of two (1 to 3), and females will lay additional clutches if the preceding clutches are removed. Both sexes build nests and incubate the eggs. Molt begins during incubation and body molt may be completed annually in breeding pairs. However, remiges are replaced sequentially over 2 to 3 years, or abruptly every 2 to 3 years in other species. Most immature birds replace their juvenal remiges over a 2 to 3 year period. Stress interferes with reproduction in cranes by reducing egg production or terminating the reproductive effort. In other birds, stress elevates corticosterone levels and decreases LHRH release. We know little about the physiological response of cranes to stress.

Main and interactive effects of arsenic and selenium on mallard reproduction and duckling growth and survival

USGS Publications Warehouse

Stanley, T.R.; Spann, J.W.; Smith, G.J.; Rosscoe, R.

1994-01-01

Arsenic (As) and selenium (Se) occur together in high concentrations in the environment and can accumulate in aquatic plants and invertebrates consumed by waterfowl. Ninety-nine pairs of breeding mallards (Anas platyrhynchos) were fed diets supplemented with As (sodium arsenate) at 0, 25, 100, or 400 ug/g, in combination with Se (seleno-DL-methionine) at 0 or 10 ug/g, in a replicated factorial experiment. Ducklings produced were placed on the same treatment combination as their parents. Arsenic accumulated in adult liver and egg, reduced adult weight gain and liver weight, delayed the onset of egg laying, decreased whole egg weight, and caused eggshell thinning. Arsenic did not affect hatching success and was not teratogenic. In ducklings, As accumulated in the liver and reduced body weight, growth, and liver weight. Arsenic did not increase duckling mortality, but it did decrease overall duckling production. Selenium accumulated in adult liver and egg, was teratogenic, and decreased hatching success. Selenium did not affect adult weight, liver weight, survival, onset of egg laying, egg fertility, egg weight, or eggshell thickness. In ducklings, Se accumulated in the liver and reduced body weight and growth, and increased liver weight. Selenium increased duckling mortality and decreased overall duckling production. Antagonistic interactions between As and Se occurred whereby As reduced Se accumulation in liver and egg, and alleviated the effects of Se on hatching success and embryo deformities. It was demonstrated that As and Se, in the chemical forms and at the dietary levels administered in this study, can adversely affect mallard reproduction and duckling growth and survival, and that As can alleviate toxic effects of Se.

Pathology and distribution of velogenic viscerotropic newcastle disease virus in the reproductive system of vaccinated and unvaccinated laying hens (gallus gallus domesticus) by immunohistochemical labelling

USDA-ARS?s Scientific Manuscript database

This study investigated the pathological changes in the reproductive system of laying hens that lead to the poor egg production and quality in Newcastle disease (ND) and the distribution of the virus in the system. Two hundred and forty Isa-Brown pullets were divided randomly into vaccinated and unv...

Effects of dietary ABATE® on reproductive success, duckling survival, behavior, and clinical pathology in game-farm mallards

USGS Publications Warehouse

Franson, J. Christian; Spann, James W.; Heinz, Gary; Bunck, Christine M.; Lamont, Thair

1983-01-01

Forty-four pairs of game-farm mallards (Anas platyrhynchos) were fed ABATE® 4E (temephos) to yield 0, 1, or 10 ppm ABATE® beginning before the initiation of lay, and terminating when ducklings were 21 days of age. The mean interval between eggs laid was greater for hens fed 10 ppm ABATE® than for controls. Clutch size, fertility, hatchability, nest attentiveness of incubating hens, and avoidance behavior of ducklings were not significantly affected by ABATE® ingestion. The percentage survival of ducklings to 21 days of age was significantly lower in both treated groups than in controls, but brain acetylcholinesterase (AChE) activity was not inhibited in young which died before termination of the study. In 21-day-old ducklings, aspartate aminotransferase (AST) activity increased and plasma nonspecific cholinesterase (ChE) activity was inhibited by about 20% in both treatment groups, but there were no significant differences in brain AChE or plasma alanine aminotransferase (ALT) activities, or plasma uric acid concentration. Clinical chemistry values of adults were not affected. No ABATE®, ABATE® sulfoxide, or ABATE® sulfone residues were found in eggs or tissue samples.

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.

Mercury accumulation and loss in mallard eggs

USGS Publications Warehouse

Heinz, G.H.; Hoffman, D.J.

2004-01-01

Female mallards (Anas platyrhynchos) were fed diets containing 5, 10, or 20 ppm mercury as methylmercury chloride. One egg was collected from each bird before the start of the mercury diets and 15 eggs were collected from each bird while it was being fed mercury. The mercury diets were then replaced by uncontaminated diets, and each female was allowed to lay 29 more eggs. Mercury levels in eggs rose to about 7,18, and 35 ppm wet-weight in females fed 5,10, or 20 ppm mercury, respectively. Mercury levels fell to about 0.16,0.80, and 1.7 ppm in the last egg laid by birds that had earlier been fed 5, 10, or 20 ppm mercury, respectively. Higher concentrations of mercury were found in egg albumen than in yolk, and between 95 and 100% of the mercury in the eggs was in the form of methylmercury.

Effects of the usage of dried brewing yeast in the diets on the performance, egg traits and blood parameters in quails.

PubMed

Yalçın, S; Erol, H; Ozsoy, B; Onbaşılar, I; Yalçın, S

2008-12-01

This experiment was carried out to determine the effects of the usage of dried brewing yeast in quail diets on laying performance, egg traits and blood parameters. A total of 240 Japanese quails (Coturnix coturnix japonica) aged 10 weeks were randomly allocated into one control group and three treatment groups. Each group was divided into five replicates as subgroups, comprising 12 quails each. Dried brewing yeast (Saccharomyces cerevisiae) was used at the levels of 1.5%, 3.0% and 4.5% in the diets of the first, second and third treatment groups, respectively. Soyabean meal was replaced with dried brewing yeast. The diets were formulated to be isocaloric and isonitrogenous. The experimental period lasted 18 weeks. Dietary treatments did not significantly affect body weight, daily feed intake, daily protein intake, egg production, egg weight, feed efficiency, mortality, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit, the percentages of egg shell, albumen and yolk, excreta moisture and small intestinal pH. Inclusion of 3% and 4.5% dried brewing yeast in diets reduced egg yolk cholesterol concentration as mg per yolk and mg per g yolk (P < 0.01). Blood serum cholesterol of groups fed diets with dried brewing yeast was significantly lower (P < 0.01) than that of the control group. Feeding diets containing 3.0% and 4.5% dried brewing yeast resulted in significant increases (P < 0.01) in blood serum levels of total protein, alanine aminotransferase at the end of the experiment. Blood serum levels of uric acid, triglyceride, aspartate aminotransferase and alkaline phosphatase were not affected by dietary dried brewing yeast. It is concluded that dried brewing yeast can be used up to 4.5% in the diets of laying quails without adverse effects on the measured parameters.

Egg production and egg quality in free-range laying hens housed at different outdoor stocking densities.

PubMed

Campbell, D L M; Lee, C; Hinch, G N; Roberts, J R

2017-09-01

Free-range laying hen systems are increasing in number within Australia. Variation in outdoor stocking densities has led to development of a national information standard on free-range egg labeling, including setting a maximum density of 10,000 hens per hectare. However, there are few data on the impacts of differing outdoor densities on production and egg quality. ISA Brown hens in small (150 hens) flocks were housed in identical indoor pens, each with access (from 21 weeks) to different sized ranges simulating one of three outdoor stocking densities (2 replicates each: 2,000 hens/hectare (ha), 10,000 hens/ha, 20,000 hens/ha). Hen-day production was tracked from 21 through 35 weeks with eggs visually graded daily for external deformities. All eggs laid on one day were weighed each week. Eggs were collected from each pen at 25, 30, and 36 weeks and analyzed for egg quality. There were no effects of outdoor stocking density on average hen-day percentage production (P = 0.67), egg weight (P = 0.09), percentages of deformed eggs (P = 0.30), shell reflectivity (P = 0.74), shell breaking strength (P = 0.07), shell deformation (P = 0.83), or shell thickness (P = 0.24). Eggs from hens in the highest density had the highest percentage shell weight (P = 0.004) and eggs from the lowest density had the highest yolk color score (P < 0.001). The amount of cuticle present did not differ between densities (P = 0.95) but some aspects of shell colors (P ≤ 0.01) and location of protoporphyrin IX (P = 0.046) varied. Hen age affected the majority of measurements. Stocking density differences may be related to hen diet as previous radio-frequency identification tracking of individual hens in these flocks showed birds used the range for longer in the lowest density and the least in the highest density, including depleting the range of vegetation sooner in the smaller ranges. An additional study assessing the relationship between individual hen range use, nutrition, and egg quality is warranted. © 2017 Poultry Science Association Inc.

Influence of grinding size of the main cereal of the diet on egg production and eggs quality of brown egg laying hens from 33 to 65 weeks of age.

PubMed

Herrera, J; Saldaña, B; Cámara, L; Berrocoso, J D; Mateos, G G

2018-04-17

The influence of grinding size of the main cereal of the diet on production and egg quality traits was studied in brown hens from 33 to 65 wk of age. The experiment was completely randomized with 6 treatments arranged as a 3 × 2 factorial with 3 main cereals (barley, corn, and wheat) and 2 grinding size of the cereal (6 and 10 mm screen). Each treatment was replicated 11 times (10 hens/replicate). Diets were isonutritive and contained 2,740 kcal/kg AMEn and 16.8% CP. Egg production, ADFI, egg weight, and feed conversion ratio (FCR) were determined by period (4 wk) and for the entire experiment. Egg quality traits (percentage of undergrades, Haugh units, thickness, strength, color of the shell, and proportion of albumen, yolk, and shell) were measured also by period. No interactions between main cereal and grinding size of the main cereal of the diet were observed for any of the traits studied. Feed intake, egg production, and BW gain were not affected by diet or grinding size. Eggs were heavier (P < 0.01) in hens fed barley than in hens fed corn or wheat, probably because of the higher fat content of the barley diets. Also, FCR tended to improve in hens fed barley compared with hens fed corn or wheat (P = 0.07). Diet did not affect any of the egg quality traits studied. In summary, barley and wheat conveniently supplemented with enzymes, can be used in substitution of corn at levels of up to 55% in diets for laying hens, without any adverse effect on egg production or egg quality traits. Moreover, the substitution of corn by a combination of barley and supplemental fat increased egg size. Consequently, the inclusion of one or other cereal in the diet will depend primarily on their relative cost. Within the range studied, screen size (6 vs. 10 mm) of the cereal had limited effects on hen production.

The effect of perch access during pullet rearing and egg laying on physiological measures of stress in White Leghorns at 71 weeks of age.

PubMed

Yan, F F; Hester, P Y; Cheng, H W

2014-06-01

Egg laying strains of chickens have a strong motivation to perch. Providing caged chickens with perches allows them to perform their natural perching behavior and also improves their musculoskeletal health due to exercise. Little is known about the effect of perch access for hens on physiological measures of stress. Our hypothesis was that denying chickens access to perches would elicit a stress response. The objective of this study was to determine the effect of perch access during all or part of life cycle on physiological homeostasis in caged 71-wk-old White Leghorn hens. A total of 1,064 chicks were assigned randomly to cages with and without perches (n = 14 pullet cages/perch treatment) on day of hatch. As pullets aged, chicks were removed from cages to provide more space. At 17 wk of age, 324 chickens in total were assigned to laying cages consisting of 4 treatments with 9 replicates per treatment. Treatment 1 chickens never had access to perches during their life cycle. Treatment 2 chickens had access to perches only from 17 to 71 wk of age (laying phase). Treatment 3 chickens had access to perches only from hatch to 16.9 wk of age (pullet phase). Treatment 4 chickens always had access to perches during their life cycle. At 71 wk of age, chickens were sampled for measurement of plasma catecholamines (epinephrine, norepinephrine, and dopamine) and corticosterone; blood serotonin and Trp; fluctuating asymmetry of shank length and width; and adrenal weight. Only shank width differed among treatments. Chickens with previous exposure to perches during the pullet phase had wider shanks than chickens without access to perches (P = 0.006), suggesting that early perching promoted skeletal development. These results suggest that a stress response was not elicited in 71-wk-old White Leghorn hens that always had access to perches compared with hens that never had access to perches during all or part of their life cycle. Poultry Science Association Inc.

Non-transferable signals on ant queen eggs

NASA Astrophysics Data System (ADS)

D'Ettorre, Patrizia; Tofilski, Adam; Heinze, Jürgen; Ratnieks, Francis L. W.

2006-03-01

How biological systems resolve internal conflicts is a major evolutionary question. Social insect workers cooperate but also pursue individual interests, such as laying male eggs. The rewards of this individual selfishness can be reduced by policing, such as by killing worker-laid eggs. However, selfish individuals may evade policing. What factors prevent individuals from being able to evade policing? In the ant Pachycondyla inversa, workers kill (police) worker-laid eggs. Because the colony keeps eggs in piles and worker-laid and queen-laid eggs are chemically distinct, worker-laid eggs might become more acceptable once placed in the egg pile by odour transfer from touching queen-laid eggs. Here, we show that such “cue scrambling” does not occur. Worker-laid eggs that were sandwiched between three queen-laid eggs for 45 min were not more acceptable in a policing bioassay than control worker-laid eggs. Chemical analyses also showed that the surface hydrocarbon profile of these eggs was unchanged. Policing, therefore, is stable against this potential cheating mechanism probably because queen-laid eggs are made chemically distinct using chemicals, that are not easily transferred by physical contact.

Non-transferable signals on ant queen eggs.

PubMed

D'Ettorre, Patrizia; Tofilski, Adam; Heinze, Jürgen; Ratnieks, Francis L W

2006-03-01

How biological systems resolve internal conflicts is a major evolutionary question. Social insect workers cooperate but also pursue individual interests, such as laying male eggs. The rewards of this individual selfishness can be reduced by policing, such as by killing worker-laid eggs. However, selfish individuals may evade policing. What factors prevent individuals from being able to evade policing? In the ant Pachycondyla inversa, workers kill (police) worker-laid eggs. Because the colony keeps eggs in piles and worker-laid and queen-laid eggs are chemically distinct, worker-laid eggs might become more acceptable once placed in the egg pile by odour transfer from touching queen-laid eggs. Here, we show that such "cue scrambling" does not occur. Worker-laid eggs that were sandwiched between three queen-laid eggs for 45 min were not more acceptable in a policing bioassay than control worker-laid eggs. Chemical analyses also showed that the surface hydrocarbon profile of these eggs was unchanged. Policing, therefore, is stable against this potential cheating mechanism probably because queen-laid eggs are made chemically distinct using chemicals, that are not easily transferred by physical contact.

Chemical Communication and Reproduction Partitioning in Social Wasps.

PubMed

Dani, Francesca Romana; Turillazzi, Stefano

2018-05-22

Social wasps encompass species displaying diverse social organization regarding colony cycle, nest foundation, caste differences (from none to significant dimorphism) and number of reproductive queens. Current phylogenetic data suggests that sociality occured independently in the subfamily Stenogastrinae and in the Polistinae+Vespinae clade. In most species, including those with the simplest social organization, colony reproduction is monopolised by a single or few females. Since their nest mates can also develop ovaries and lay eggs, dominant females must somehow inhibit them from reproducing. Physical interactions in the form of open aggression or, usually, ritualised dominance by the fertile females contribute to fertility inhibition in several species, but it is unlikely to function in large colonies. In the latter case, reproduction within the colony is likely to be regulated through pheromones. Relatively little is known about these semiochemicals. Studies on all the three social wasp subfamilies, revealed that cuticular hydrocarbon components differ in abundance between egg-laying and not egg-laying females and that their composition depends on fertility status. In several species, females have been reported to manifestly react towards females with activated ovaries, but there is little evidence to support the hypothesis that fertile individuals are either recognized through their CHC composition, or that over-represented CHC constituents can inhibit fertility. Moreover, very little information exists on the possibility that exocrine glands release fertility signals or chemicals inhibiting fertility.

Improving productive performance and mitigating harmful emissions from laying hen excreta via feeding on graded levels of corn DDGS with or without Bacillus subtilis probiotic.

PubMed

Abd El-Hack, M E; Mahgoub, S A; Alagawany, M; Ashour, E A

2017-10-01

An experiment that included some inclusions of corn distillers dried grains with solubles (DDGS) with or without supplementation of probiotic bacteria to Hi-sex Brown laying hen diets was conducted to evaluate the impacts on performance, egg quality, blood metabolites and nitrogen and phosphorus excretion in the manure. A total of 216 twenty-two-week-old Hi-sex Brown laying hens were randomly divided into eight treatment groups in a factorial design (4 × 2) experiment, which included four levels of DDGS (0, 50, 100 and 150 g/kg diet) plus two levels of Bacillus subtilis probiotic (0 or 1000 mg/kg diet, with a concentration of 1.5 × 108 CFU/g of dried product). The experimental period extended from 22 to 34 weeks of age. The results showed that linear increase in DDGS level up to 150 g/kg improved (p ≤ 0.01) the values of feed consumption, egg shape index and yolk colour compared to the control and other treatment groups. Inclusion of dietary DDGS up to 150 g/kg in layer diets led to a significant decrease in egg mass and a significant increase in Haugh unit score compared to other groups. In the bacillus group, the values of feed conversion, egg weight and egg mass enhanced by 6.45, 3.27 and 7.60% respectively compared with the control diet. Total protein, albumin, triglycerides, cholesterol, calcium and ammonia in serum were significantly (p ≤ 0.01) influenced by DDGS inclusion. The excreted nitrogen decreased by 8.62 and 4.31% in hens fed 50 or 100 g/kg of DDGS respectively, while excreted phosphorous decreased by 3.33, 7.22 and 10.56% in hens fed 50, 100 or 150 g/kg of DDGS respectively as compared to the control group. It could be concluded that increasing DDGS inclusion level in the diet up to 10% and the supplementation of probiotic bacteria improved the productive performance of laying hens and mitigated the harmful emissions from chicken manure; this means better production within environmentally friendly conditions. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Single and Combined Impacts of Vitamin A and Selenium in Diet on Productive Performance, Egg Quality, and Some Blood Parameters of Laying Hens During Hot Season.

PubMed

Abd El-Hack, Mohamed E; Mahrose, Khalid; Askar, Ali A; Alagawany, Mahmoud; Arif, Muhammad; Saeed, Muhammad; Abbasi, Farzana; Soomro, Rab Nawaz; Siyal, Farman Ali; Chaudhry, Maria Tabassum

2017-05-01

A study was conducted using 162 Bovans laying hens to investigate the impacts of extra dietary vitamin A (0, 8000, 16,000 IU/kg), selenium (0, 0.25, 0.50 mg/kg), and their combinations on the performance, egg quality, and blood biological parameters of laying hens during summer months. Supplemental vitamin A up to 16,000 IU/kg diet significantly (P < 0.05) improved all productive traits studied except feed intake which increased with 8000 IU/kg diet compared with control. Feed intake and feed conversion of hens fed diet supplemented with selenium revealed high statistical (P = 0.001) differences. All egg quality criteria were not significantly (P < 0.05) affected by dietary vitamin A except albumin percentage and Haugh units, since Haugh unit score was gradually increased with increasing vitamin A level. Vitamin A-enriched groups showed significant (P < 0.05 and 0.01) decreases in plasma albumen, total lipids, and total cholesterol in respect to the unsupplemented groups. Compared with unsupplemented groups, total protein, albumin, total lipid, and total cholesterol were increased in selenium-enriched groups. There were no significant impacts of selenium treatments in layer diets on thyroid hormones and liver enzymes studied except alanine transferase (ALT) and thyroxin (T 4 ), as compared with the control group. Hematological parameters were not affected by vitamin A treatment except PCV% which decreased with vitamin A supplementation. Hemoglobin and lymphocytes were increased with increasing dietary selenium level. In conclusion, the combined supplementary concentrations of vitamin A (16,000 IU/kg) and selenium (0.25 mg/kg) might be needed for better production and health of laying hens reared under heat stress conditions.

Effects of Curcuma longa rhizome powder on egg quality, performance and some physiological indices of laying hens fed different levels of metabolizable energy.

PubMed

Mirbod, Mahsa; Mahdavi, Amir Hossein; Samie, Abdol-Hossein; Mehri, Mehran

2017-03-01

High-energy diets of laying hens may improve roductive performance, although some negative effects may also appear with respect to egg quality and physiological parameters. Curcuma longa rhizome powder (CRP) has beneficial effects on health indices of the birds through antioxidant and antimicrobial properties, especially when the birds experience nutritional stress. Increasing dietary CRP enhanced egg quality by improving eggshell thickness and hardness but decreasing yolk cholesterol content (P < 0.05). The best feed conversion ratio was obtained in birds fed high-apparent metabolizable energy (AME) diets supplemented with 2.0 g kg -1 CRP (P < 0.05). Although increasing dietary AME elevated the serum concentration of triglycerides (P < 0.05) and enzymatic activities of alanine aminotransferase and aspartate aminotransferase (P < 0.05), dietary inclusion of CRP alleviates the blood levels of these enzymes (P < 0.01). Low level of dietary CRP boosted the immune responses to Newcastle virus (P < 0.01) and sheep red blood cells (P < 0.05) antigens but decreased the heterophil to lymphocyte ratio (P < 0.05). Inclusion of at least 2.0 g kg -1 CRP in the diet of laying decreased Escherichia coli enumerations in the ileal content (P < 0.01) and improved villus height, crypt depth and goblet cell numbers (P < 0.05). An improvement in the productive performance of laying hens fed high-energy diets might be associated with decreasing health indices and product quality, which could potentially be amended by nutritional modifications such as incorporating medicinal herbs in the feed. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Study of formation of green eggshell color in ducks through global gene expression.

PubMed

Xu, Fa Qiong; Li, Ang; Lan, Jing Jing; Wang, Yue Ming; Yan, Mei Jiao; Lian, Sen Yang; Wu, Xu

2018-01-01

The green eggshell color produced by ducks is a threshold trait that can be influenced by various factors, such as hereditary, environment and nutrition. The aim of this study was to investigate the genetic regulation of the formation of eggs with green shells in Youxian ducks. We performed integrative analysis of mRNAs and miRNAs expression profiling in the shell gland samples from ducks by RNA-Seq. We found 124 differentially expressed genes that were associated with various pathways, such as the ATP-binding cassette (ABC) transporter and solute carrier supper family pathways. A total of 31 differentially expressed miRNAs were found between ducks laying green eggs and white eggs. KEGG pathway analysis of the predicted miRNA target genes also indicated the functional characteristics of these miRNAs; they were involved in the ABC transporter pathway and the solute carrier (SLC) supper family. Analysis with qRT-PCR was applied to validate the results of global gene expression, which showed a correlation between results obtained by RNA-seq and RT-qPCR. Moreover, a miRNA-mRNA interaction network was established using correlation analysis of differentially expressed mRNA and miRNA. Compared to ducks that lay white eggs, ducks that lay green eggs include six up-regulated miRNAs that had regulatory effects on 35 down-regulated genes, and seven down-regulated miRNAs which influenced 46 up-regulated genes. For example, the ABC transporter pathway could be regulated by expressing gga-miR-144-3p (up-regulated) with ABCG2 (up-regulated) and other miRNAs and genes. This study provides valuable information about mRNA and miRNA regulation in duck shell gland tissues, and provides foundational information for further study on the eggshell color formation and marker-assisted selection for Youxian duck breeding.

Productive performance, eggshell quality, and eggshell ultrastructure of laying hens fed diets supplemented with organic trace minerals.

PubMed

Stefanello, C; Santos, T C; Murakami, A E; Martins, E N; Carneiro, T C

2014-01-01

This study was carried out with the purpose of evaluating the effect of supplementing hens' diets with trace minerals from inorganic or organic sources on the productive performance, eggshell quality, and eggshell ultrastructure of laying hens. Three hundred sixty Hy-Line W36 laying hens between 47 to 62 wk of age were used and distributed in a completely randomized experimental design with 9 treatments, 5 replicates, and 8 birds for each experimental unit. The treatments consisted of a control diet without supplementation of the trace minerals Mn, Zn, and Cu; 4 supplementation levels of these trace minerals from an inorganic source; and the same levels of supplementation from an organic source (proteinates). The supplementation levels in milligrams per kilogram for Mn, Zn, and Cu, were, respectively, 35-30-05, 65-60-10, 95-90-15, and 125-120-20. There was no effect of supplementation of trace minerals on the rate of posture, feed intake, feed conversion, specific weight, and Haugh unit of eggs. However, there was a quadratic effect (P < 0.05) of the levels of trace mineral supplementation on average egg weight and egg mass; the results did not differ regarding the source used. The increase in the levels of supplementation of Mn, Zn, and Cu provided a linear increase (P < 0.05) in the breaking strength and the percentage of eggshell. There was a linear decrease (P < 0.05) in the egg loss and the number of mammillary buttons in the shell. The best results were obtained using diets supplemented with trace minerals from an organic source because these diets provided lower egg loss, higher thickness, and increased strength of the shell. Structurally, organic Mn, Zn, and Cu provided higher thickness of the palisade layer and lower mammillary density. The trace mineral supplementation improved the structural characteristics and the quality of the eggshells.

A new type of ant-decapitation in the Phoridae (Insecta: Diptera)

PubMed Central

Kung, Giar-Ann; Porras, Wendy

2015-01-01

Abstract The genus Dohrniphora is a hyperdiverse group of phorid flies, a family whose species are commonly characterized as generalized scavengers. The lifestyle of most species of Dohrniphora is unknown, although one cosmopolitan, synanthropic species, D. cornuta (Bigot) fits the general scavenger mold. Here we show that flies of the D. longirostrata species group exhibit highly specific “headhunting” behavior in which injured Odontomachus ants are decapitated, the heads dragged away, and females either feed on their contents or lay an egg nearby. Since most females studied lacked eggs in their ovaries, we conclude that this bizarrely specialized feeding is necessary to provide nutrients for reproduction in these flies. Our study provides further evidence that injured ants are a common, stable resource in tropical ecosystems that support a wide array of phorid flies. Such narrowly constrained lifestyles, as exemplified by exclusively feeding on and breeding in the head contents of certain ponerine worker ants, could allow the co-existence of a huge community of saprophagous flies. PMID:25709534

Biosafety assessment of Gd@C82(OH)22 nanoparticles on Caenorhabditis elegans

NASA Astrophysics Data System (ADS)

Zhang, Wendi; Sun, Baoyun; Zhang, Longze; Zhao, Baolu; Nie, Guangjun; Zhao, Yuliang

2011-06-01

Gd@C82(OH)22, a water-soluble endohedral metallofullerene derivative, has been proven to possess significant antineoplastic activity in mice. Toxicity studies of the nanoparticle have shown some evidence of low or non toxicity in mice and cell models. Here we employed Caenorhabditis elegans (C. elegans) as a model organism to further evaluate the short- and long-term toxicity of Gd@C82(OH)22 and possible behavior changes under normal and stress culture conditions. With treatment of Gd@C82(OH)22 at 0.01, 0.1, 1.0 and 10 μg ml-1 within one generation (short-term), C. elegans showed no significant decrease in longevity or thermotolerance compared to the controls. Furthermore, when Gd@C82(OH)22 treatment was extended up to six generations (long-term), non-toxic effects to the nematodes were found. In addition, data from body length measurement, feeding rate and egg-laying assays with short-term treatment demonstrated that the nanoparticles have no significant impact on the individual growth, feeding behavior and reproductive ability, respectively. In summary, this work has shown that Gd@C82(OH)22 is tolerated well by worms and it has no apparent toxic effects on longevity, stress resistance, growth and behaviors that were observed in both adult and young worms. Our work lays the foundations for further developments of this anti-neoplastic agent for clinical applications.

Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens.

PubMed

Stratmann, A; Fröhlich, E K F; Gebhardt-Henrich, S G; Harlander-Matauschek, A; Würbel, H; Toscano, M J

2016-05-01

The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in 8 pens of 2 aviary systems differing in design. Keel bone status and body mass of 20 focal hens per line and pen were assessed at 17, 18, 23, 30, 36, 43, 52, and 63 wk of age. External egg parameters (i.e., egg mass, eggshell breaking strength, thickness, and mass) were measured using 10 eggs per line at both 38 and 57 wk of age. Body parameters (i.e. tarsus and third primary wing feather length to calculate index of wing loading) were recorded at 38 wk of age and mortality per genetic line throughout the laying cycle. Bone mineral density (BMD) of 15 keel bones per genetic line was measured after slaughter to confirm assignment of the experimental lines. We found a greater BMD in the H compared with the L and LSL lines. Fewer keel bone fractures and deviations, a poorer external egg quality, as well as a lower index of wing loading were found in the H compared with the L line. Mortality was lower and production parameters (e.g., laying performance) were higher in the LSL line compared with the 2 experimental lines. Aviary design affected prevalence of keel bone damage, body mass, and mortality. We conclude that selection of specific bone traits associated with bone strength as well as the related differences in body morphology (i.e., lower index of wing loading) have potential to reduce keel bone damage in commercial settings. Also, the housing environment (i.e., aviary design) may have additive effects. © 2016 Poultry Science Association Inc.

Population Characteristics and the Nature of Egg Shells of two Phthirapteran Species Parasitizing Indian Cattle Egrets

PubMed Central

Ahmad, Aftab; Khan, Vikram; Badola, Smita; Arya, Gaurav; Bansal, Nayanci; Saxena, A. K.

2010-01-01

The prevalence, intensities of infestation, range of infestation and population composition of two phthirapteran species, Ardeicola expallidus Blagoveshtchensky (Phthiraptera: Philopteridae) and Ciconiphilus decimfasciatus Boisduval and Lacordaire (Menoponidae) on seventy cattle egrets were recorded during August 2004 to March 2005, in India. The frequency distribution patterns of both the species were skewed but did not correspond to the negative binomial model. The oviposition sites, egg laying patterns and the nature of the eggs of the two species were markedly different. PMID:21067416

Predation risk affects growth and reproduction of an invasive snail and its lethal effect depends on prey size

PubMed Central

Guo, Jing; Martín, Pablo R.; Zhang, Chunxia

2017-01-01

The behavior of invasive species under predation risk has been studied extensively, but their growth and reproductive responses have rarely been investigated. We conducted experiments with juveniles and adults of the invasive freshwater snail Pomacea canaliculata, and we observed changes in growth and reproduction in response to predation risk from a caged predator (Trachemys scripta elegans). P. canaliculata produced eggs earlier in the presence of predators and injured conspecifics compared with the control group (no risk), although the total number of egg masses laid by per female was exceeded by that of the controls after 15 days. Egg hatching success noticeably decreased under predation risk, and the incubation period was significantly prolonged; however, the oviposition height of the snails was not affected. A lethal effect of predation risk was detected in juvenile snails but not in adults. The growth of juvenile P. canaliculata was inhibited under predation risk, probably due to a reduction in food intake. Adult females exhibited a greater reduction in growth under predation risk than males, which likely resulted in part from the high reproductive investment of females in egg laying. These results indicate that P. canaliculata snails under predation risk face a trade-off between predator avoidance and growth and reproduction, where the lethal effect of predation risk is linked to the size of the prey. PMID:29136660

The Caenorhabditis elegans Female-Like State: Decoupling the Transcriptomic Effects of Aging and Sperm Status.

PubMed

Angeles-Albores, David; Leighton, Daniel H W; Tsou, Tiffany; Khaw, Tiffany H; Antoshechkin, Igor; Sternberg, Paul W

2017-09-07

Understanding genome and gene function in a whole organism requires us to fully comprehend the life cycle and the physiology of the organism in question. Caenorhabditis elegans XX animals are hermaphrodites that exhaust their sperm after 3 d of egg-laying. Even though C. elegans can live for many days after cessation of egg-laying, the molecular physiology of this state has not been as intensely studied as other parts of the life cycle, despite documented changes in behavior and metabolism. To study the effects of sperm depletion and aging of C. elegans during the first 6 d of adulthood, we measured the transcriptomes of first-day adult hermaphrodites and sixth-day sperm-depleted adults, and, at the same time points, mutant fog-2(lf) worms that have a feminized germline phenotype. We found that we could separate the effects of biological aging from sperm depletion. For a large subset of genes, young adult fog-2(lf) animals had the same gene expression changes as sperm-depleted sixth-day wild-type hermaphrodites, and these genes did not change expression when fog-2(lf) females reached the sixth day of adulthood. Taken together, this indicates that changing sperm status causes a change in the internal state of the worm, which we call the female-like state. Our data provide a high-quality picture of the changes that happen in global gene expression throughout the period of early aging in the worm. Copyright © 2017 Angeles-Albores et al.

Sex-biased hatching order and adaptive population divergence in a passerine bird.

PubMed

Badyaev, Alexander V; Hill, Geoffrey E; Beck, Michelle L; Dervan, Anne A; Duckworth, Renee A; McGraw, Kevin J; Nolan, Paul M; Whittingham, Linda A

2002-01-11

Most species of birds can lay only one egg per day until a clutch is complete, and the order in which eggs are laid often has strong and sex-specific effects on offspring growth and survival. In two recently established populations of the house finch (Carpodacus mexicanus) in Montana and Alabama, breeding females simultaneously adjusted the sex and growth of offspring in relation to their position in the laying order, thereby reducing the mortality of sons and daughters by 10 to 20% in both environments. We show experimentally that the reduction in mortality is produced by persistent and sex-specific maternal effects on the growth and morphology of offspring. These strong parental effects may have facilitated the rapid adaptive divergence among populations of house finches.

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.

Utilizing fungus myceliated grain for molt induction and performance in commercial laying hens.

PubMed

Willis, W L; Isikhuemhen, O S; Allen, J W; Byers, A; King, K; Thomas, C

2009-10-01

Molting in poultry is used to rejuvenate hens for a second or third laying cycle. Feed withdrawal was once the most effective method used for molt induction; however, it has being phased out due to food safety and animal welfare concerns. This study evaluated the utilization of fungus myceliated grain as a safe and effective alternative for inducing molt, enhancing immunity, reducing Salmonella growth, and returning to egg production. Laying hens were subjected to 1 of 5 treatments: 1) nonfed (NF), 2) full-fed (FF), 3) fungus myceliated meal (FM), 4) 90% fungus myceliated meal+10% standard layer ration (FM-90), and 5) 90% alfalfa meal+10% fungus myceliated meal (AF-90). Each treatment condition was replicated 9 times during a 9-d molt period. The results revealed that egg production for treatments 1 and 3 ceased completely by d 5, whereas hens in treatments 4 and 5 ceased egg production by d 6. The percentage of BW loss decreased significantly (P<0.05) in treatments 1 (57%), 2 (8%), 3 (35%), 4 (37%), and 5 (44%). Ovary weights of hens fed all molting diets decreased significantly from the full-fed control but did not differ significantly (P<0.05) from each other. Salmonella population in the crop, ovary, and ceca from hens differed significantly (P<0.05) among treatments. Return to egg production differed between treatments with higher production beginning in treatment 3 and ending in treatment 5. Antibody titers did differ (P<0.05) among treatments. From these results, fungus myceliated meal appears to be a viable alternative to conventional feed withdrawal and other methods for the successful induction of molt and retention of postmolt performance.

High quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird.

PubMed

González-Medina, Erick; Castillo-Guerrero, José Alfredo; Herzka, Sharon Zinah; Fernández, Guillermo

2018-01-01

Understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. In birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. To assess the role of diet in the physiological condition of female blue-footed booby, Sula nebouxii (BFBO), during reproduction we evaluated whether individual differences in diet (assessed by using δ13C and δ15N values of whole blood from female birds and muscle tissue of the principal prey species) prior to egg laying and during incubation influenced their lipid metabolic profile (measured as triglyceride levels and C:N ratio) and their reproductive performance (defined by laying date, clutch size and hatching success). Females with higher δ15N values in their blood during the courtship and incubation periods had a higher lipid metabolic profile, earlier laying date, greater clutch size (2-3 eggs) and higher hatching success. Females that laid earlier and more eggs (2-3 eggs) consumed more Pacific anchoveta (Cetengraulis mysticetus) and Pacific thread herring (Opisthonema libertate) than did other females. These two prey species also had high amounts of lipids (C:N ratio) and caloric content (Kcal/g fresh weight). The quality of food consumed by females at the beginning of reproduction affected their physiological condition, as well as their short-term reproductive performance. Our work emphasizes the importance of determining the influence of food quality during reproduction to understand the reproductive decisions and consequences in long-lived animals.

High quality diet improves lipid metabolic profile and breeding performance in the blue-footed booby, a long-lived seabird

PubMed Central

González-Medina, Erick; Castillo-Guerrero, José Alfredo; Herzka, Sharon Zinah

2018-01-01

Understanding the role of diet in the physiological condition of adults during reproduction and hence its effect on reproductive performance is fundamental to understand reproductive strategies in long-lived animals. In birds, little is known about the influence of the quality of food consumed at the beginning of the reproductive period and its short-term effects on reproductive performance. To assess the role of diet in the physiological condition of female blue-footed booby, Sula nebouxii (BFBO), during reproduction we evaluated whether individual differences in diet (assessed by using δ13C and δ15N values of whole blood from female birds and muscle tissue of the principal prey species) prior to egg laying and during incubation influenced their lipid metabolic profile (measured as triglyceride levels and C:N ratio) and their reproductive performance (defined by laying date, clutch size and hatching success). Females with higher δ15N values in their blood during the courtship and incubation periods had a higher lipid metabolic profile, earlier laying date, greater clutch size (2–3 eggs) and higher hatching success. Females that laid earlier and more eggs (2–3 eggs) consumed more Pacific anchoveta (Cetengraulis mysticetus) and Pacific thread herring (Opisthonema libertate) than did other females. These two prey species also had high amounts of lipids (C:N ratio) and caloric content (Kcal/g fresh weight). The quality of food consumed by females at the beginning of reproduction affected their physiological condition, as well as their short-term reproductive performance. Our work emphasizes the importance of determining the influence of food quality during reproduction to understand the reproductive decisions and consequences in long-lived animals. PMID:29462199

Quality of eggs from Lohmann Brown Classic laying hens fed black soldier fly meal as substitute for soya bean.

PubMed

Secci, G; Bovera, F; Nizza, S; Baronti, N; Gasco, L; Conte, G; Serra, A; Bonelli, A; Parisi, G

2018-01-08

Soya bean is the main protein source in poultry feed but rising prices make an alternative protein source necessary. Insects, such as the black soldier fly (Hermetia illucens), may be an attractive solution for hens, although little information is available on their effect on egg quality. The present study aims to fill this gap by testing the effect of 100% replacement of soya bean with H. illucens larva meal in the diet of Lohmann Brown Classic laying hens for 21 weeks. At the end of the trial, the eggs were characterized for parameters such as weight, colour, proximate composition of albumen and yolk, and content of carotenoids, tocopherols and cholesterol. The fatty acid profile of yolks was also determined. Hens fed the insect-based diet produced eggs (HIM group) with a higher proportion of yolk than the group fed the soya bean-based diet (SBM group). HIM was associated with redder yolks (red index 5.63 v. 1.36) than SBM. HIM yolks were richer in γ-tocopherol (4.0 against 2.4 mg/kg), lutein (8.6 against 4.9 mg/kg), β-carotene (0.33 against 0.19 mg/kg) and total carotenoids (15 against 10.5 mg/kg) than SBM yolks. The fatty acid composition of HIM yolks was almost identical to that of SBM yolks. Finally, HIM yolks contained 11% less cholesterol than SBM yolks. These results suggest that H. illucens larva meal is a suitable total substitute for soya bean meal in the diet of Lohmann Brown Classic laying hens. A sustainable alternative to the plant protein source therefore seems feasible.

Observation and Quantification of Mating Behavior in the Pinewood Nematode, Bursaphelenchus xylophilus.

PubMed

Zhu, Najie; Bai, Liqun; Schütz, Stefan; Liu, Baojun; Liu, Zhenyu; Zhang, Xingyao; Yu, Hongshi; Hu, Jiafu

2016-12-25

A method for observing and quantifying the mating behavior of the pinewood nematode, Bursaphelenchus xylophilus, was established under a stereomicroscope. To improve the mating efficiency of B. Xylophilus and to increase the chances of mating observation, virgin adults were cultured and used for the investigation. Eggs were obtained by keeping the nematodes in water and allowing the females to lay eggs for 10 min. The second-stage juveniles (J2) were synchronized by incubating the eggs for 24 h at 25 °C in the dark, and the early J4 were obtained by culturing the J2 with grey mold, Botrytis cinerea, for another 52 h. At this time point, most J4 nematodes could be clearly distinguished as being male or female using their genital morphology. The male and female J4 were collected and cultured separately in two different Petri dishes for 24 h to get virgin adult nematodes. A virgin male and a virgin female were paired in a drop of water in the well of a concave slide. The mating behavior was filmed with a video recorder under a stereomicroscope. The whole period of the mating process was 82.8 ±3.91 min (mean ±SE) and could be divided into 4 different phases: searching, contacting, copulating, and lingering. The mean minutes of duration were 21.8 ± 2.0, 28.0 ± 1.9, 25.8 ± 0.7 and 7.2 ± 0.5, respectively. Eleven sub-behaviors were described: cruising, approaching, encountering, touching, hooping, locating, attaching, ejaculating, separating, quiescence, and roaming. Interestingly, obvious intra-sexual competition was observed when one female was grouped with 3 males or one male with 3 females. This protocol is useful and valuable, not only in investigating the mating behavior of B. xylophilus, but also in acting as a reference for ethological studies of other nematodes.

Pasture, multi-enzymes, benzoic acid and essential oils positively influence performance, intestinal organ weight and egg quality in free-range laying hens.

PubMed

Iqbal, Z; Roberts, J; Perez-Maldonado, R A; Goodarzi Boroojeni, F; Swick, R A; Ruhnke, I

2018-04-01

1. The objective of this study was to investigate the effect of range type, multi-enzyme applications, and a combination of benzoic acid (BA) and essential oils (EO) on the productive performance, organ weight and egg quality of free-range laying hens. 2. Three hundred laying hens were evaluated for the short-term (6 weeks) and long-term (12 weeks) effects of range type (G = no pasture, P = pasture) and feed additives (T1 = control; T2 = betaglucanase/pectinase/protease; T3 = BA/EO). Body weight, feed intake (FI), feed conversion ratio (FCR), egg production (EP), digestive organ weight, and egg quality (EQ) were evaluated. Data were analysed using SPSS 2.2 in a 2×2×3 factorial arrangement. 3. Hens that ranged on pasture were significantly heavier (2043 g vs. 1996 g; p < 0.001), laid heavier eggs (61.9 g vs. 60.3 g; p < 0.001) and produced darker yolk colour (4.3 vs. 7.0; p < 0.001) compared to hens ranged on gravel. Hens fed T2 were significantly heavier (2050 g) compared to hens fed T1 (2005 g) or T3 (2008 g). Organ weights (gizzard, liver and pancreas) were significantly heavier in hens ranged on pasture (16.8 g/kg BW, 22.3 g/kg BW and 1.89 g/kg BW, respectively) compared to hens ranged on gravel (14.2 g/kg BW, 21.7 g/kg BW and 1.83 g/kg BW, respectively). Over time, body weight (1970-2070 g; p < 0.001) and egg weight (59.5-62.8 g; p < 0.001) increased, FI (123-120 g; p = 0.024) was reduced and FCR (2.36-2.10; p = 0.002) improved 4. In conclusion, hens housed on pasture and fed multi-enzyme supplemented diets had significantly heavier body weight and produced heavier eggs with darker yolk colour. Pasture intake and enzyme supplementation increased digestive organ weight significantly.

Effect of feeder space during the growing and laying periods and the rate of feed increase at the onset of lay on broiler breeder female reproductive function.

PubMed

Leksrisompong, N; Romero-Sanchez, H; Oviedo-Rondón, E O; Brake, J

2014-07-01

A study was conducted to examine how 2 feeder space allocations during the rearing period followed by 2 feeder space allocations after photostimulation and 2 female feeding to peak programs (fast or slow) affected female broiler breeder reproductive performance and mortality. Sixteen pens of 76 breeder females each were equipped with either 4 tube feeders with a 132 cm circumference pan (7.0 cm/female) or 6 feeders (10.4 cm/female) to 21 wk of age. Thereafter, 64 females were moved to breeding pens, photostimulated, and fed sex-separate from either 3 (6.2 cm/female) or 5 (10.3 cm/female) feeders with either fast or slow feeding to peak feeding programs applied to complete a 2 × 2 × 2 factorial design. Seven males that were separately reared in a similar manner were added per pen. Individual female BW was determined at 6, 20, and 32 wk of age and BW uniformity assessed. Greater feeder space during rearing increased BW at 32 wk of age, whereas greater feeder space during lay or slow feeding to peak decreased BW at 32 wk. There were no differences in BW uniformity. Hens from the 10.4 to 10.3 cm/female combination produced a significantly greater number of eggs as compared with the 7.0 to 10.3 cm/female and 10.4 to 6.2 cm/female combinations with the 7.0 to 6.2 cm/female combination intermediate. Percentage hen-day egg production of the 10.4 to 10.3 cm/female combination hens was significantly greater than all other combinations. Livability was improved in the 10.4 to 10.3 cm/female combination relative to the 7.0 to 10.3 cm/female combination with the others intermediate. The fast feeding to peak program increased yolk weight as well as yolk:albumen ratio at 28 and 30 wk of age, but egg weight did not differ. These data indicated that increased or decreased feeder space between the growing and laying periods did not affect broiler breeder female BW, uniformity, egg weight, fertility, or hatchability. The 10.3 cm/female laying feeder space exhibited the best hen-day egg production in combination with 10.4 cm/pullet rearing but not with 7.0 cm/pullet rearing space. In a similar manner, hen mortality was greater in the 7.0 to 10.3 cm/female feeder space combination that the 10.4 to 10.3 cm/female combination. © 2014 Poultry Science Association Inc.

Egg Drop Syndrome-76 (EDS-76) in Japanese quails (Coturnix coturnix japonica): an experimental study revealing pathology, effect on egg production/quality and immune responses.

PubMed

Mohapatra, Narayan; Kataria, Jag Mohan; Chakraborty, Sandip; Dhama, Kuldeep

2014-06-01

Egg Drop Syndrome-76 (EDS-76) is a recognized disease of chickens and Japanese Quails, which is of high economic importance due to its drastic negative effects on egg production in laying birds. The aim of the present study was to better understand the EDS-76 viral disease process in Japanese quails (Coturnix coturnix japonica), since very limited studies have been conducted in this species of birds. For this purpose, an experimental study was conducted with infection of EDS-76 virus in laying Japanese quails to reveal pathology, effect on egg production/quality and immune responses of this virus in these birds. By 7, 9 and 13-15 Days Post Infection (DPI), drop as well as aberrant egg production and lower mean egg quality were observed compared to control birds. Significant histopathological changes were observed in genitalia and spleen. Haemagglutination Inhibition (HI) and Enzyme Linked Immunosorbent Assay (ELISA) titres rose rapidly by 2nd week when it became maximum; thereafter declined and maintained at low levels up to 10 week post infection. The mean total protein values in infected quail gradually increased to 4.10±0.05/100 mL without any change in mean albumen value at 12 DPI. In conclusion, the course of the EDS-76 is significant not only in chickens but also in quails even though it occurs occasionally in quails. Explorative pathological, blood biochemical and immunological studies are suggested during EDS-76 viral disease course in quails. This would aid in formulating effective disease prevention and control measures for this economically important disease of poultry.

Spawning strategy in Atlantic bobtail squid Sepiola atlantica (Cephalopoda: Sepiolidae)

NASA Astrophysics Data System (ADS)

Rodrigues, Marcelo; Garcí, Manuel E.; Troncoso, Jesús S.; Guerra, Ángel

2011-03-01

This study aimed to determine the spawning strategy in the Atlantic bobtail squid Sepiola atlantica, in order to add new information to the knowledge of its reproductive strategy. A total of 12 females that spawned in aquaria were examined. Characteristics of the reproductive traits and egg clutches were similar to those of other known Sepiolidae. Clutch size varied from 31 up to 115 eggs. Females of this species had incorporated up to 1.58 times of their body weight into laid eggs. The size of laid eggs showed a positive correlation with maternal body size, supporting the idea that female size is a determinant of egg size. Our data suggest that S. atlantica is an intermittent terminal spawner , and that its spawning strategy comprises group-synchronous ovary maturation, multiple egg laying, and deposition of egg clutches in different locations. The obtained data provide insights for future comparative studies on reproductive allocation.

Allocation of limited reserves to a clutch: A model explaining the lack of a relationship between clutch size and egg size

USGS Publications Warehouse

Flint, Paul L.; Grand, James B.; Sedinger, James S.

1996-01-01

Lack (1967, 1968) proposed that clutch size in waterfowl is limited by the nutrients available to females when producing eggs. He suggested that if nutrients available for clutch formation are limited, then species producing small eggs would, on average, lay more eggs than species with large eggs. Rohwer (1988) argues that this model should also apply within species. Thus, the nutrition-limitation hypothesis predicts a tradeoff among females between clutch size and egg size (Rohwer 1988). Field studies of single species consistently have failed to detect a negative relationship between clutch size and egg size (Rohwer 1988, Lessells et al. 1992, Rohwer and Eisenhauer 1989, Flint and Sedinger 1992, Flint and Grand 1996). The absence of such a relationship within species has been regarded as evidence against the hypothesis that nutrient availability limits clutch size (Rohwer 1988, 1991, 1992; Rohwer and Eisenhauer 1989).

Dietary inclusion of raw faba bean instead of soybean meal and enzyme supplementation in laying hens: Effect on performance and egg quality.

PubMed

Abd El-Hack, M E; Alagawany, M; Laudadio, V; Demauro, R; Tufarelli, V

2017-02-01

An experiment was conducted with 160 Hisex Brown laying hens to evaluate the effect of different inclusion levels of faba bean (FB) and enzyme supplementation on productive performance and egg quality parameters. The experimental diets consisted of five levels of FB: 0% (control), 25%, 50%, 75% and 100%, substituting soybean meal (SBM), and two levels of enzyme supplementation (0 or 250 mg/kg). Each dietary treatment was assigned to four replicate groups and the experiment lasted 22 weeks. A positive relationship ( P  < 0.05) was found between FB inclusion and body weight (BW) change of hens when compared to those of the control treatment. Enzyme supplementation significantly affected the final hens' BW. Feed consumption (FC) of hens was statistically increased with increasing FB level up to 50%. Supplementing dietary enzyme mixture at 250 mg/kg led to improvement in FC at all studied ages ( P  < 0.05). Inclusion of 25% or 50% FB in diets had no adverse effects on feed conversion ratio (FCR) compared to the higher FB inclusion levels (75% or 100%). Egg weight (EW), egg number (EN) and egg mass (EM) were significantly ( P  < 0.05) influenced by FB inclusion in diet during the entire experimental periods, except for EN and EM at 20-24 weeks of age. Egg productive parameters were not influenced by enzyme mixture supplementation ( P  > 0.05). The main effect of FB levels replacing for SBM affected ( P  < 0.05) yolk and shell percentages, yolk index, yolk to albumen ratio, shell thickness and egg shape index. It can be concluded that FB and enzyme supplementation could be included in hens diet at less than 50% instead of SBM to support egg productive performance, however higher raw FB levels negatively affected egg production indices and quality.

Using different ratios of bitter vetch (Vicia ervilia) seed for moult induction and post-moult performance in commercial laying hens.

PubMed

Mohammadi, L; Sadeghi, Gh

2009-03-01

1. The applicability of different ratios of bitter vetch seed as a new method for moult induction in laying hens was studied. The effectiveness of bitter vetch seed on post-moult production and post-moult egg quality was also investigated. 2. A total of 120 Single Comb White Leghorn hens, 78 weeks of age, were used in this study. The hens were randomly assigned to 5 treatment groups of 24 birds each. The treatments were 30% bitter vetch seed (BV30) diet, 60% bitter vetch seed (BV60) diet, 90% bitter vetch seed (90BV) diet, feed withdrawal method (FW) and full-fed non-moulted control (CON). 3. Egg production ceased first in FW and BV90 treated hens and last in BV30 treated hens. As the percentage of bitter vetch seed increased in the moulting ration, feed intake decreased and body weight loss increased during the 10-d moult induction period. Time to first egg production was significantly greater in hens exposed to the FW and BV90 diets. 4. FW and BV90 treatment hens had significantly higher hen-d egg production than non-moulted control hens. Egg weight was significantly higher in BV30 and BV90 treatments. There were no differences in egg mass, feed intake and mortality among experimental treatments during the post-moult period. 5. No significant improvements were observed in exterior or interior egg quality in moulted hens, except for Haugh units, which were significantly higher in moulted hens when compared to the non-moulted control hens. 6. In conclusion, the present study showed ad libitum feeding of a layer ration with 90% of bitter vetch seed for 10 d proved to be effective for inducing moult, increasing post-moult egg production and improving some internal egg quality parameters.

Deposition and depletion of decoquinate in eggs after administration of cross-contaminated feed.

PubMed

Olejnik, Małgorzata; Szprengier-Juszkiewicz, Teresa

2015-01-01

Decoquinate, a chemical coccidiostat used as a feed additive, can occur in eggs due to cross-contamination of feedstuffs for laying hens. An experiment was designed to assess the transfer of decoquinate to hen eggs and its distribution between egg yolk and egg white. Hens were given the feed containing decoquinate at a cross-contamination level (0.34 mg kg(-1)) and collected eggs were analysed using an LC-MS/MS method. The plateau level was reached on the eighth day of the experiment and averaged 8.91 µg kg(-1), which is far below the maximum level established at 20 µg kg(-1) for whole eggs. Decoquinate was deposited mostly in egg yolks (26.2 µg kg(-1)) and did not deplete completely during 14 days of administration of decoquinate-free feed. The results confirmed that administration of cross-contaminated feed is associated with very low risk of non-compliant residue levels of decoquinate in eggs.

Low protein and high-energy diet: a possible natural cause of fatty liver hemorrhagic syndrome in caged White Leghorn laying hens.

PubMed

Rozenboim, I; Mahato, J; Cohen, N A; Tirosh, O

2016-03-01

Fatty liver hemorrhagic syndrome (FLHS) is a metabolic condition of chicken and other birds caused by diverse nutritional, hormonal, environmental, and metabolic factors. Here we studied the effect of different diet composition on the induction of FLHS in single comb White Leghorn (WL) Hy-line laying hens. Seventy six (76) young WL (26 wks old) laying hens and 69 old hens (84 wks old) of the same breed were each divided into 4 treatment groups and provided 4 different diet treatments. The diet treatments included: control (C), 17.5% CP, 3.5% fat (F); normal protein, high fat (HF), 17.5% CP, 7% F; low protein, normal fat (LP), 13% CP, 3.5% F; and low protein, high fat (LPHF), 13% CP, 6.5% F. The diets containing high fat also had a higher ME of 3,000 kcal/kg of feed while the other 2 diets with normal fat had a regular lower amount of ME (2750 kcal/kg). Hen-day egg production (HDEP), ADFI, BW, egg weight, plasma enzymes indicating liver damage (alkaline phosphatase [ALP], aspartate aminotransferase [AST], gamma-glutamyl transferase [GGT]), liver and abdominal fat weight, liver color score (LCS), liver hemorrhagic score (LHS), liver fat content (LFC), liver histological examination, lipid peroxidation product in the liver, and genes indicating liver inflammation were evaluated. HDEP, ADFI, BW, and egg weight were significantly decreased in the LPHF diet group, while egg weight was also decreased in the LP diet group. In the young hens (LPHF group), ALP was found significantly higher at 30 d of diet treatment and was numerically higher throughout the experiment, while AST was significantly higher at 105 d of treatment. LCS, LHS, and LFC were significantly higher in young hens on the LPHF diet treatment. A liver histological examination shows more lipid vacuolization in the LPHF treatment diet. HF or LP alone had no significant effect on LFC, LHS, or LCS. We suggest that LP in the diet with higher ME from fat can be a possible natural cause for predisposing laying hens to FLHS. © 2016 Poultry Science Association Inc.

Effects of rearing systems on laying performance, egg quality, and serum biochemistry of Xianju chickens in summer.

PubMed

Dong, X Y; Yin, Z Z; Ma, Y Z; Cao, H Y; Dong, D J

2017-09-01

The objective of this study was to compare the laying performance, egg quality, and serum biochemistry of hens maintained in conventional cage rearing system (CRS), flat net-rearing system (NRS), and free range system (FRS) under summer conditions. Indigenous Xianju chickens (n = 540) were randomly allocated into cages or pens of rearing system groups, within each system there were 5 replicates with 36 hens in each replicate. The experiment lasted between 21 and 29 wk of age. Hen-day egg production (P = 0.00) and egg mass (P = 0.00) were higher in the CRS but were similar in the NRS and FRS. Lowest egg weight (P = 0.02), yolk weight (P = 0.00) and yolk ratio (P = 0.01), and feed intake (P = 0.01) were observed from the FRS, whereas lowest feed conversion ratio (FCR) was recorded from the CRS (P = 0.01). Rearing systems had negligible effect on egg quality. Serum Ca (P = 0.04) and total protein (P = 0.03) levels were found to be higher in the CRS but were lower in the FRS. Serum levels of glucose (P = 0.01), cholesterol (P = 0.00), and triglyceride (P = 0.00) in the CRS increased compared with the NRS and FRS groups, whereas serum levels of high density lipoprotein cholesterol (HDL-C; P = 0.01) in the CRS decreased. It can be concluded that under summer conditions, Xianju chickens from CRS had an advantage in terms of productivity parameters, but exhibited higher levels of serum lipids and glucose. © 2017 Poultry Science Association Inc.

Assessing the sustainability of egg production systems in The Netherlands.

PubMed

van Asselt, E D; van Bussel, L G J; van Horne, P; van der Voet, H; van der Heijden, G W A M; van der Fels-Klerx, H J

2015-08-01

Housing systems for laying hens have changed over the years due to increased public concern regarding animal welfare. In terms of sustainability, animal welfare is just one aspect that needs to be considered. Social aspects as well as environmental and economic factors need to be included as well. In this study, we assessed the sustainability of enriched cage, barn, free-range, and organic egg production systems following a predefined protocol. Indicators were selected within the social, environmental, and economic dimensions, after which parameter values and sustainability limits were set for the core indicators in order to quantify sustainability. Uncertainty in the parameter values as well as assigned weights and compensabilities of the indicators influenced the outcome of the sustainability assessment. Using equal weights for the indicators showed that, for the Dutch situation, enriched cage egg production was most sustainable, having the highest score on the environmental dimension, whereas free-range egg production gave the highest score in the social dimension (covering food safety, animal welfare, and human welfare). In the economic dimension both enriched cage egg and organic egg production had the highest sustainability score. When weights were attributed according to stakeholder outputs, individual differences were seen, but the overall scores were comparable to the sustainability scores based on equal weights. The provided method enabled a quantification of sustainability using input from stakeholders to include societal preferences in the overall assessment. Allowing for different weights and compensabilities helps policymakers in communicating with stakeholders involved and provides a weighted decision regarding future housing systems for laying hens. © 2015 Poultry Science Association Inc.

Periodic matrix models for seasonal dynamics of structured populations with application to a seabird population.

PubMed

Cushing, J M; Henson, Shandelle M

2018-02-03

For structured populations with an annual breeding season, life-stage interactions and behavioral tactics may occur on a faster time scale than that of population dynamics. Motivated by recent field studies of the effect of rising sea surface temperature (SST) on within-breeding-season behaviors in colonial seabirds, we formulate and analyze a general class of discrete-time matrix models designed to account for changes in behavioral tactics within the breeding season and their dynamic consequences at the population level across breeding seasons. As a specific example, we focus on egg cannibalism and the daily reproductive synchrony observed in seabirds. Using the model, we investigate circumstances under which these life history tactics can be beneficial or non-beneficial at the population level in light of the expected continued rise in SST. Using bifurcation theoretic techniques, we study the nature of non-extinction, seasonal cycles as a function of environmental resource availability as they are created upon destabilization of the extinction state. Of particular interest are backward bifurcations in that they typically create strong Allee effects in population models which, in turn, lead to the benefit of possible (initial condition dependent) survival in adverse environments. We find that positive density effects (component Allee effects) due to increased adult survival from cannibalism and the propensity of females to synchronize daily egg laying can produce a strong Allee effect due to a backward bifurcation.

Influence of supplemental dietary poultry fat, phytase, and 25-hydroxycholecalciferol on the egg characteristics of commercial layers inoculated before or at the onset of lay with F-strain Mycoplasma gallisepticum

USDA-ARS?s Scientific Manuscript database

The effects of 2 supplemental levels of dietary poultry fat (PF) and the combination of PF, phytase (PHY) and 25-hydroxycholecalciferol (D3) on the egg characteristics of commercial layers inoculated with F-strain Mycoplasma gallisepticum (FMG) were investigated in 2 trials. Sham and FMG inoculatio...

Effect of dietary fermented mushroom bed on egg production in laying hens.

PubMed

Yoshida, Shu; Mitani, Hiroaki; Kamata, Masato; Ohtsuka, Akira; Otomaru, Konosuke; Obi, Takeshi; Kanouchi, Hiroaki

2017-11-01

Egg productivity is declined by stress. It has been reported that some food supplements can improve the egg productivity due to a reduction of environmental stress. We evaluated the effect of fermented waste mushroom bed (FWMB) as a dietary additive on egg productivity. Hens were fed control food (control group, n = 100) or 3% FWMB-added food (FWMB group, n = 100) for 16 months. The number of eggs, soft-shelled eggs, and broken eggs were recorded for 15 months. We also evaluated stress-related markers (ovotransferrin, lipid peroxide, and the heterophil-to-lymphocyte ratio). The FWMB group had slightly increased egg production compared with control hens. The FWMB group produced significantly less broken and soft-shelled eggs than the control group. All stress-related markers were significantly lower in the FWMB group than in the control group. Gut flora was also affected by FWMB feeding. The increased egg production and decreased proportion of broken and soft-shelled eggs might be related to the prevention of stressful conditions by FWMB.

[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.

Chronic acceleration and egg production in domestic fowl

NASA Technical Reports Server (NTRS)

Smith, A. H.; Besch, E. L.; Burton, R. R.

1985-01-01

A study of the influence of chronic acceleration on egg production of commercially raised hens placed on a large animal centrifuge at 90 days of age, was performed. S8 generation hens were stepped up from 1.25 G to 2 G, which was maintained for 30 days. Fifty percent ceased to be in the laying condition at 1.5 G, and 10.8 percent suffered oviduct prolapse above 1.8 G. S21 generation hens had no incidents of oviduct prolapse despite 170-day retention at 2 G, and, assuming a 30 percent population not in the laying condition, approximated the commercial production rate. Chronic acceleration did not appear to affect the relative sizes of albumen or yolk, but it did appear to reduce the relative shell size, consistent with a decrease in plasma calcium. Dry matter content was not affected.

Plasma luteinizing hormone and the development of ovarian follicles after loss of clutch in female mallards (Anas platyrhynchos)

USGS Publications Warehouse

Donham, R.S.; Dane, C.W.; Farner, D.S.

1976-01-01

The plasma level of LH and the extent of development of ovarian follicles were analyzed in incubating female Mallards. In both wild and game-farm stock, incubation was associated with a significant decline in plasma levels of LH from those of laying females. Within 1 day after removal of eggs, LH levels had increased to levels indistinguishable from those of laying females. The mean diameter of the largest follicle in wild females on the tenth day of incubation was 5.3 mm; it was 5.2 mm in game-farm stock at the same stage. Three days following removal of eggs, the mean of the largest follicles of wild-stock hens had increased to 14.0 mm and those of game-farm stock to 12.7 mm.

Livebearing or egg-laying mammals: 27 decisive nucleotides of FAM168.

PubMed

Pramanik, Subrata; Kutzner, Arne; Heese, Klaus

2017-05-23

In the present study, we determine comprehensive molecular phylogenetic relationships of the novel myelin-associated neurite-outgrowth inhibitor (MANI) gene across the entire eukaryotic lineage. Combined computational genomic and proteomic sequence analyses revealed MANI as one of the two members of the novel family with sequence similarity 168 member (FAM168) genes, consisting of FAM168A and FAM168B, having distinct genetic differences that illustrate diversification in its biological function and genetic taxonomy across the phylogenetic tree. Phylogenetic analyses based on coding sequences of these FAM168 genes revealed that they are paralogs and that the earliest emergence of these genes occurred in jawed vertebrates such as Callorhinchus milii. Surprisingly, these two genes are absent in other chordates that have a notochord at some stage in their lives, such as branchiostoma and tunicates. In the context of phylogenetic relationships among eukaryotic species, our results demonstrate the presence of FAM168 orthologs in vertebrates ranging from Callorhinchus milii to Homo sapiens, displaying distinct taxonomic clusters, comprised of fish, amphibians, reptiles, birds, and mammals. Analyses of individual FAM168 exons in our sample provide new insights into the molecular relationships between FAM168A and FAM168B (MANI) on the one hand and livebearing and egg-laying mammals on the other hand, demonstrating that a distinctive intermediate exon 4, comprised of 27 nucleotides, appears suddenly only in FAM168A and there in the livebearing mammals only but is absent from all other species including the egg-laying mammals.

Unravelling proteome changes of chicken egg whites under carbon dioxide modified atmosphere packaging.

PubMed

Xu, Lei; Jia, Fei; Luo, Changyao; Yu, Qianqian; Dai, Ruitong; Li, Xingmin

2018-01-15

Unfertilized chicken eggs within 24h of laying were chosen and stored at 25°C and 45% humidity for 0, 20, and 40days. The experimental group (EG) was the carbon dioxide-modified atmosphere packaging (CDMAP) group, whereas the control group (CG) contained eggs without special handling. Egg freshness indexes were measured. The proteome of the egg whites was determined by LC-MS/MS using isobaric tags for relative and absolute quantitation (iTRAQ). A total of 87 proteins were detected. The results indicated that CDMAP can control the change in protein abundance. Using a correlation analysis between the protein abundance and freshness indexes of the EG, Beta-hexosaminidase, Trypsin inhibitor ClTI-1 and Apolipoprotein D were determined to be potential predictors of egg freshness. In comparing the proteomes of the EG and CG, it was concluded that CDMAP could affect the proteins related to egg vitelline membranes, eggshell matrix and metabolic intensity to maintain egg freshness. Copyright © 2017. Published by Elsevier Ltd.

Spacelab

NASA Image and Video Library

1994-07-01

Astronaut Donald Thomas conducts the Fertilization and Embryonic Development of Japanese Newt in Space (AstroNewt) experiment at the Aquatic Animal Experiment Unit (AAEU) inside the International Microgravity Laboratory-2 (IML-2) science module. The AstroNewt experiment aims to know the effects of gravity on the early developmental process of fertilized eggs using a unique aquatic animal, the Japanese red-bellied newt. The newt egg is a large single cell at the begirning of development. The Japanese newt mates in spring and autumn. In late autumn, female newts enter hibernation with sperm in their body cavity and in spring lay eggs and fertilize them with the stored sperm. The experiment takes advantage of this feature of the newt. Groups of newts were sent to the Kennedy Space Center and kept in hibernation until the mission. The AAEU cassettes carried four newts aboard the Space Shuttle. Two newts in one cassette are treated by hormone injection on the ground to simulate egg laying. The other two newts are treated on orbit by the crew. The former group started maturization of eggs before launch. The effects of gravity on that early process were differentiated by comparison of the two groups. The IML-2 was the second in a series of Spacelab flights designed to conduct research by the international science community in a microgravity environment. Managed by the Marshall Space Flight Center, the IML-2 was launched on July 8, 1994 aboard the STS-65 Space Shuttle mission, Orbiter Columbia.

Spacelab

NASA Image and Video Library

1994-07-01

Astronaut Donald Thomas conducts the Fertilization and Embryonic Development of Japanese Newt in Space (AstroNewt) experiment at the Aquatic Animal Experiment Unit (AAEU) inside the International Microgravity Laboratory-2 (IML-2) science module. The AstroNewt experiment aims to know the effects of gravity on the early developmental process of fertilized eggs using a unique aquatic animal, the Japanese red-bellied newt. The newt egg is a large single cell at the begirning of development. The Japanese newt mates in spring and autumn. In late autumn, female newts enter hibernation with sperm in their body cavity and in spring lay eggs and fertilized them with the stored sperm. The experiment takes advantage of this feature of the newt. Groups of newts were sent to the Kennedy Space Center and kept in hibernation until the mission. The AAEU cassettes carried four newts aboard the Space Shuttle. Two newts in one cassette are treated by hormone injection on the ground to simulate egg laying. The other two newts are treated on orbit by the crew. The former group started maturization of eggs before launch. The effects of gravity on that early process were differentiated by comparison of the two groups. The IML-2 was the second in a series of Spacelab flights designed to conduct research by the international science community in a microgravity environment. Managed by the Marshall Space Flight Center, the IML-2 was launch on July 8, 1994 aboard the STS-65 Space Shuttle Orbiter Columbia mission.

Variation in clutch size in relation to nest size in birds

PubMed Central

Møller, Anders P; Adriaensen, Frank; Artemyev, Alexandr; Bańbura, Jerzy; Barba, Emilio; Biard, Clotilde; Blondel, Jacques; Bouslama, Zihad; Bouvier, Jean-Charles; Camprodon, Jordi; Cecere, Francesco; Charmantier, Anne; Charter, Motti; Cichoń, Mariusz; Cusimano, Camillo; Czeszczewik, Dorota; Demeyrier, Virginie; Doligez, Blandine; Doutrelant, Claire; Dubiec, Anna; Eens, Marcel; Eeva, Tapio; Faivre, Bruno; Ferns, Peter N; Forsman, Jukka T; García-Del-Rey, Eduardo; Goldshtein, Aya; Goodenough, Anne E; Gosler, Andrew G; Góźdź, Iga; Grégoire, Arnaud; Gustafsson, Lars; Hartley, Ian R; Heeb, Philipp; Hinsley, Shelley A; Isenmann, Paul; Jacob, Staffan; Järvinen, Antero; Juškaitis, Rimvydas; Korpimäki, Erkki; Krams, Indrikis; Laaksonen, Toni; Leclercq, Bernard; Lehikoinen, Esa; Loukola, Olli; Lundberg, Arne; Mainwaring, Mark C; Mänd, Raivo; Massa, Bruno; Mazgajski, Tomasz D; Merino, Santiago; Mitrus, Cezary; Mönkkönen, Mikko; Morales-Fernaz, Judith; Morin, Xavier; Nager, Ruedi G; Nilsson, Jan-Åke; Nilsson, Sven G; Norte, Ana C; Orell, Markku; Perret, Philippe; Pimentel, Carla S; Pinxten, Rianne; Priedniece, Ilze; Quidoz, Marie-Claude; Remeš, Vladimir; Richner, Heinz; Robles, Hugo; Rytkönen, Seppo; Senar, Juan Carlos; Seppänen, Janne T; da Silva, Luís P; Slagsvold, Tore; Solonen, Tapio; Sorace, Alberto; Stenning, Martyn J; Török, János; Tryjanowski, Piotr; van Noordwijk, Arie J; von Numers, Mikael; Walankiewicz, Wiesław; Lambrechts, Marcel M

2014-01-01

Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of egg-laying. Parent birds should be selected to choose nest sites and to build optimally sized nests, yet our current understanding of clutch size-nest size relationships is limited to small-scale studies performed over short time periods. Here, we quantified the relationship between clutch size and nest size, using an exhaustive database of 116 slope estimates based on 17,472 nests of 21 species of hole and non-hole-nesting birds. There was a significant, positive relationship between clutch size and the base area of the nest box or the nest, and this relationship did not differ significantly between open nesting and hole-nesting species. The slope of the relationship showed significant intraspecific and interspecific heterogeneity among four species of secondary hole-nesting species, but also among all 116 slope estimates. The estimated relationship between clutch size and nest box base area in study sites with more than a single size of nest box was not significantly different from the relationship using studies with only a single size of nest box. The slope of the relationship between clutch size and nest base area in different species of birds was significantly negatively related to minimum base area, and less so to maximum base area in a given study. These findings are consistent with the hypothesis that bird species have a general reaction norm reflecting the relationship between nest size and clutch size. Further, they suggest that scientists may influence the clutch size decisions of hole-nesting birds through the provisioning of nest boxes of varying sizes. PMID:25478150

Variation in clutch size in relation to nest size in birds.

PubMed

Møller, Anders P; Adriaensen, Frank; Artemyev, Alexandr; Bańbura, Jerzy; Barba, Emilio; Biard, Clotilde; Blondel, Jacques; Bouslama, Zihad; Bouvier, Jean-Charles; Camprodon, Jordi; Cecere, Francesco; Charmantier, Anne; Charter, Motti; Cichoń, Mariusz; Cusimano, Camillo; Czeszczewik, Dorota; Demeyrier, Virginie; Doligez, Blandine; Doutrelant, Claire; Dubiec, Anna; Eens, Marcel; Eeva, Tapio; Faivre, Bruno; Ferns, Peter N; Forsman, Jukka T; García-Del-Rey, Eduardo; Goldshtein, Aya; Goodenough, Anne E; Gosler, Andrew G; Góźdź, Iga; Grégoire, Arnaud; Gustafsson, Lars; Hartley, Ian R; Heeb, Philipp; Hinsley, Shelley A; Isenmann, Paul; Jacob, Staffan; Järvinen, Antero; Juškaitis, Rimvydas; Korpimäki, Erkki; Krams, Indrikis; Laaksonen, Toni; Leclercq, Bernard; Lehikoinen, Esa; Loukola, Olli; Lundberg, Arne; Mainwaring, Mark C; Mänd, Raivo; Massa, Bruno; Mazgajski, Tomasz D; Merino, Santiago; Mitrus, Cezary; Mönkkönen, Mikko; Morales-Fernaz, Judith; Morin, Xavier; Nager, Ruedi G; Nilsson, Jan-Åke; Nilsson, Sven G; Norte, Ana C; Orell, Markku; Perret, Philippe; Pimentel, Carla S; Pinxten, Rianne; Priedniece, Ilze; Quidoz, Marie-Claude; Remeš, Vladimir; Richner, Heinz; Robles, Hugo; Rytkönen, Seppo; Senar, Juan Carlos; Seppänen, Janne T; da Silva, Luís P; Slagsvold, Tore; Solonen, Tapio; Sorace, Alberto; Stenning, Martyn J; Török, János; Tryjanowski, Piotr; van Noordwijk, Arie J; von Numers, Mikael; Walankiewicz, Wiesław; Lambrechts, Marcel M

2014-09-01

Nests are structures built to support and protect eggs and/or offspring from predators, parasites, and adverse weather conditions. Nests are mainly constructed prior to egg laying, meaning that parent birds must make decisions about nest site choice and nest building behavior before the start of egg-laying. Parent birds should be selected to choose nest sites and to build optimally sized nests, yet our current understanding of clutch size-nest size relationships is limited to small-scale studies performed over short time periods. Here, we quantified the relationship between clutch size and nest size, using an exhaustive database of 116 slope estimates based on 17,472 nests of 21 species of hole and non-hole-nesting birds. There was a significant, positive relationship between clutch size and the base area of the nest box or the nest, and this relationship did not differ significantly between open nesting and hole-nesting species. The slope of the relationship showed significant intraspecific and interspecific heterogeneity among four species of secondary hole-nesting species, but also among all 116 slope estimates. The estimated relationship between clutch size and nest box base area in study sites with more than a single size of nest box was not significantly different from the relationship using studies with only a single size of nest box. The slope of the relationship between clutch size and nest base area in different species of birds was significantly negatively related to minimum base area, and less so to maximum base area in a given study. These findings are consistent with the hypothesis that bird species have a general reaction norm reflecting the relationship between nest size and clutch size. Further, they suggest that scientists may influence the clutch size decisions of hole-nesting birds through the provisioning of nest boxes of varying sizes.

Effect of various sources and levels of iodine, as well as the kind of diet, on the performance of young laying hens, iodine accumulation in eggs, egg characteristics, and morphotic and biochemical indices in blood.

PubMed

Słupczyńska, M; Jamroz, D; Orda, J; Wiliczkiewicz, A

2014-10-01

Young hens were fed over a period of 150 d with 2 kinds of diets including corn and soybean meal or corn, soybean, and rapeseed meal. Diets were enriched with potassium iodide (KI) or potassium iodate (KIO3) as an I source in amounts equal to 1, 3, or 5 mg of supplemented I/kg of feed. The hen performance, egg quality, hematological and morphotic indices in blood, hepatic enzyme activity, lipid indices in blood serum as well as I accumulation in wet egg content were determined. Introduction of 00-variety rapeseed meal into the diet improved the laying rate and feed conversion (P < 0.05); however, better egg weight was noted by feeding the hens with a diet without rapeseed meal. Use of KI as an I source enhanced the egg weight. The increased I level in the diet had an equivocal influence on egg weight, improved the feed conversion per 1 kg of eggs, and decreased the proportion of damaged eggs. The use of corn, soybean, and rapeseed meal in hen diets significantly improved yolk color; similar results were noted after an increase in I levels in the diets after 3 mo of feeding. Hematological indices of hen blood demonstrated significantly higher red blood cells numbers and hemoglobin concentrations with the use of KI. The use of a diet containing rapeseed meal led to an enhancement of hepatic enzyme activity, especially of alkaline phosphatase (P = 0.007). Lipid metabolism indices were not influenced by the kind of diet or the I source or level. The accumulation of I in wet egg content was negatively influenced by the use of a diet containing rapeseed meal (P = 0.000). The application of KI as an I source enhanced (P = 0.003) the accretion of I in eggs after 5 mo of treatment. Enhanced I supply significantly increased accumulation of I in eggs (P = 0.000) after 3 and 5 mo of the experiment from 260 and 310 to 1,011 and 1,256 µg/kg of wet egg content, respectively. ©2014 Poultry Science Association Inc.

Effects of dietary vanadium in mallard ducks

USGS Publications Warehouse

White, D.H.; Dieter, M.P.

1978-01-01

Adult mallard ducks fed 0, 1, 10, or 100 ppm vanadyl sulfate in the diet were sacrificed after 12 wk on treatment; tissues were analyzed for vanadium. No birds died during the study and body weights did not change. Vanadium accumulated to higher concentrations in the bone and liver than in other tissues. Concentrations in bones of hens were five times those in bones of drakes, suggesting an interaction between vanadium and calcium mobilization in laying hens. Vanadium concentrations in most tissues were significantly correlated and increased with treatment level. Lipid metabolism was altered in laying hens fed 100 ppm vanadium. Very little vanadium accumulated in the eggs of laying hens.

Myoinhibiting Peptides are the Ancestral Ligands of the Promiscuous Drosophila Sex Peptide Receptor

DTIC Science & Technology

2010-01-01

decreases the willingness to re-mate, induces egg production and egg laying, stimulates food intake, enhances antimicrobial peptide synthesis and reduces...polypropylene tubes, centrifuged to remove cell debris, and the supernatants dried. Each sample was dissolved in 250 ll of assay buffer (0.05 M Tris, 4...variations during the cDNA synthesis step, all RNA samples were reverse transcribed simultaneously. Furthermore, several negative control reactions, i.e

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

Influences of population density on polyandry and patterns of sperm usage in the marine gastropod Rapana venosa.

PubMed

Xue, Dong-Xiu; Zhang, Tao; Liu, Jin-Xian

2016-03-21

Polyandry is a common mating strategy in animals, with potential for sexual selection to continue post-copulation through sperm competition and/or cryptic female choice. Few studies have investigated the influences of population density on polyandry and sperm usage, and paternity distribution in successive broods of marine invertebrates. The marine gastropod Rapana venosa is ideal for investigating how population density influences the frequency of polyandry and elucidating patterns of sperm usage. Two different population density (12 ind/m(3) and 36 ind/m(3)) treatments with two replications were set to observe reproductive behaviors. Five microsatellite markers were used to identify the frequency of multiple paternity and determine paternal contributions to progeny arrays in 120 egg masses. All of the mean mating frequency, mean number of sires and mean egg-laying frequency were higher at high population density treatment relative to low population density treatment, indicating population density is an important factor affecting polyandry. The last sperm donors achieved high proportions of paternity in 74.77% of egg masses, which supported the "last male sperm precedence" hypothesis. In addition, high variance in reproductive success among R. venosa males were detected, which might have an important influence on effective population size.

Influences of population density on polyandry and patterns of sperm usage in the marine gastropod Rapana venosa

PubMed Central

Xue, Dong-Xiu; Zhang, Tao; Liu, Jin-Xian

2016-01-01

Polyandry is a common mating strategy in animals, with potential for sexual selection to continue post-copulation through sperm competition and/or cryptic female choice. Few studies have investigated the influences of population density on polyandry and sperm usage, and paternity distribution in successive broods of marine invertebrates. The marine gastropod Rapana venosa is ideal for investigating how population density influences the frequency of polyandry and elucidating patterns of sperm usage. Two different population density (12 ind/m3 and 36 ind/m3) treatments with two replications were set to observe reproductive behaviors. Five microsatellite markers were used to identify the frequency of multiple paternity and determine paternal contributions to progeny arrays in 120 egg masses. All of the mean mating frequency, mean number of sires and mean egg-laying frequency were higher at high population density treatment relative to low population density treatment, indicating population density is an important factor affecting polyandry. The last sperm donors achieved high proportions of paternity in 74.77% of egg masses, which supported the “last male sperm precedence” hypothesis. In addition, high variance in reproductive success among R. venosa males were detected, which might have an important influence on effective population size. PMID:26996441

Effects of rice bran on performance, egg quality, oxidative status, yolk fatty acid composition, and fatty acid metabolism-related gene expression in laying ducks.

PubMed

Ruan, D; Lin, Y C; Chen, W; Wang, S; Xia, W G; Fouad, A M; Zheng, C T

2015-12-01

The study was designed to evaluate the effects of different dietary levels of rice bran (RB) in laying duck diets on performance, egg quality, oxidation status, egg yolk fatty acid composition, and hepatic expression of fatty acid metabolism-related genes. Longyan females (1080) with similar BW at 19 wk of age were randomly assigned to 6 dietary treatments, each consisting of 6 replicates of 30 birds. The basal diet (I) was a typical corn-soybean ration while the experimental diets (II to VI) substituted RB for corn and wheat bran and a small reduction of soybean meal. The level of substitution in diets (II to VI) was 6%, 12%, 18%, 24%, and 30%, respectively. The experiment lasted for 12 wks. Average egg weight and daily egg mass decreased linearly as the level of RB inclusion increased (P<0.001) and feed conversion ratio linearly increased (P<0.001). The proportions of C14:0 and C18:0 and total saturated fatty acids (SFA) in egg yolk linearly decreased with increasing RB, and many of the key polyunsaturated fatty acids (PUFA), like C18:2 n-6 and C18:3 n-3, linearly increased (P<0.001), but not those of C20:5 n-3 and C22:6 n-3. There were linear decreases (P<0.001) in hepatic abundance of FAS and SREBP1 transcripts, with a substantial reduction to about 30% those of ducks fed the control diet; there were no treatment effects on productive performance, eggshell thickness, strength, Haugh unit, antioxidation status, and egg yolk cholesterol or triglyceride content (P>0.05). In conclusion, the current study suggests that ducks from 19 to 31 wk could be fed diets with up to about 18% RB without effect on the number of eggs produced, egg quality, and oxidative status. Increasing amounts of RB linearly increased egg yolk concentrations of key fatty acids like C18:2 n-6 and C18:3 n-3 and decreased the hepatic abundance of FAS and SREBP-1 transcripts. © 2015 Poultry Science Association Inc.