Measuring the electric activity of chick embryos heart through 16 bit audio card monitored by the Goldwavetm software

NASA Astrophysics Data System (ADS)

Silva, Dilson; Cortez, Celia Martins

2015-12-01

In the present work we used a high-resolution, low-cost apparatus capable of detecting waves fit inside the sound bandwidth, and the software package GoldwaveTM for graphical display, processing and monitoring the signals, to study aspects of the electric heart activity of early avian embryos, specifically at the 18th Hamburger & Hamilton stage of the embryo development. The species used was the domestic chick (Gallus gallus), and we carried out 23 experiments in which cardiographic spectra of QRS complex waves representing the propagation of depolarization waves through ventricles was recorded using microprobes and reference electrodes directly on the embryos. The results show that technique using 16 bit audio card monitored by the GoldwaveTM software was efficient to study signal aspects of heart electric activity of early avian embryos.

Effect of coniine on the developing chick embryo.

PubMed

Forsyth, C S; Frank, A A; Watrous, B J; Bohn, A A

1994-04-01

Coniine, an alkaloid from Conium maculatum (poison hemlock), has been shown to be teratogenic in livestock. The major teratogenic outcome is arthrogryposis, presumably due to nicotinic receptor blockade. However, coniine has failed to produce arthrogryposis in rats or mice and is only weakly teratogenic in rabbits. The purpose of this study was to evaluate and compare the effects of coniine and nicotine in the developing chick. Concentrations of coniine and nicotine sulfate were 0.015%, 0.03%, 0.075%, 0.15%, 0.75%, 1.5%, 3%, and 6% and 1%, 5%, and 10%, respectively. Both compounds caused deformations and lethality in a dose-dependent manner. All concentrations of nicotine sulfate caused some lethality but a no effect level for coniine lethality was 0.75%. The deformations caused by both coniine and nicotine sulfate were excessive flexion or extension of one or more toes. No histopathological alterations or differences in bone formation were seen in the limbs or toes of any chicks from any group; however, extensive cranial hemorrhage occurred in all nicotine sulfate-treated chicks. There was a statistically significant (P < or = 0.01) decrease in movement in coniine and nicotine sulfate treated chicks as determined by ultrasound. Control chicks were in motion an average of 33.67% of the time, while coniine-treated chicks were only moving 8.95% of a 5-min interval, and no movement was observed for nicotine sulfate treated chicks. In summary, the chick embryo provides a reliable and simple experimental animal model of coniine-induced arthrogryposis. Data from this model support a mechanism involving nicotinic receptor blockade with subsequent decreased fetal movement.

Development of teeth in chick embryos after mouse neural crest transplantations.

PubMed

Mitsiadis, Thimios A; Chéraud, Yvonnick; Sharpe, Paul; Fontaine-Pérus, Josiane

2003-05-27

Teeth were lost in birds 70-80 million years ago. Current thinking holds that it is the avian cranial neural crest-derived mesenchyme that has lost odontogenic capacity, whereas the oral epithelium retains the signaling properties required to induce odontogenesis. To investigate the odontogenic capacity of ectomesenchyme, we have used neural tube transplantations from mice to chick embryos to replace the chick neural crest cell populations with mouse neural crest cells. The mouse/chick chimeras obtained show evidence of tooth formation showing that avian oral epithelium is able to induce a nonavian developmental program in mouse neural crest-derived mesenchymal cells.

Impaired cytoskeletal arrangements and failure of ventral body wall closure in chick embryos treated with rock inhibitor (Y-27632).

PubMed

Duess, Johannes W; Puri, Prem; Thompson, Jennifer

2016-01-01

Rho-associated kinase (ROCK) signaling regulates numerous fundamental developmental processes during embryogenesis, primarily by controlling actin-cytoskeleton assembly and cell contractility. ROCK knockout mice exhibit a ventral body wall defect (VBWD) phenotype due to disorganization of actin filaments at the umbilical ring. However, the exact molecular mechanisms leading to VBWD still remain unclear. Improper somitogenesis has been hypothesized to contribute to failure of VBW closure. We designed this study to investigate the hypothesis that administration of ROCK inhibitor (Y-27632) disrupts cytoskeletal arrangements in morphology during early chick embryogenesis, which may contribute to the development of VBWD. At 60 h incubation, chick embryos were explanted into shell-less culture and treated with 50 µL of vehicle for controls (n = 33) or 50 µL of 500 µM of Y-27632 for the experimental group (Y-27, n = 56). At 8 h post-treatment, RT-PCR was performed to evaluate mRNA levels of N-cadherin, E-cadherin and connexin43. Immunofluorescence confocal microscopy was performed to analyze the expression and distribution of actin, vinculin and microtubules in the neural tube and somites. A further cohort of embryos was treated in ovo by dropping 50 µL of vehicle or 50 µL of different concentrations of Y-27632 onto the embryo and allowing development to 12 and 14 days for further assessment. Gene expression levels of N-cadherin, E-cadherin and connexin43 were significantly decreased in treated embryos compared with controls (p < 0.05). Thickened actin filament bundles were recorded in the neural tube of Y-27 embryos. In somites, cells were dissociated with reduced actin distribution in affected embryos. Clumping of vinculin expression was found in the neural tube and somites, whereas reduced expression of microtubules was observed in Y-27 embryos compared with controls. At 12 and 14 days of development, affected embryos presented with an enlarged

Antioxidant activities of chick embryo egg hydrolysates

PubMed Central

Sun, Hao; Ye, Ting; Wang, Yuntao; Wang, Ling; Chen, Yijie; Li, Bin

2014-01-01

Chick embryo egg hydrolysates (CEEH) were obtained by enzymatic hydrolysis of chick embryo egg in vitro-simulated gastrointestinal digestion. The antioxidant activities of CEEH were investigated by employing three in vitro assays, including the 2,2′-azinobis-(3-ethylbenzthiazoline-6-sulfonate)/1,1-diphenyl-2-picrylhydrazyl (ABTS/DPPH)/hydroxyl radical-scavenging assays. The radical-scavenging effect of CEEH (1.0 mg/mL) was in a dose-dependent manner, with the highest trolox equivalent antioxidant capacity for ABTS, DPPH, and that of hydroxyl radicals found to be 569, 2097, and 259.6 μmol/L, respectively; whereas the trolox equivalent antioxidant capacity of unhatched egg for ABTS, DPPH, and that of hydroxyl radicals were found to be 199, 993, and 226.5 μmol/L, respectively. CEEH showed stronger scavenging activity than the hydrolysates of unhatched egg against free radicals such as ABTS, DPPH, and hydroxyl radicals. The antioxidant amino acid analysis indicated that the 14-day CEEH possess more antioxidant amino acids than that of the unhatched egg. In addition, essential amino acids analysis showed that the 14-day CEEH have the highest nutritional value. Combined with the results of the amino acid profiles, CEEH were believed to have higher nutritive value in addition to antioxidant activities than the unhatched egg. PMID:24804065

Ex Ovo Model for Directly Visualizing Chick Embryo Development

ERIC Educational Resources Information Center

Dorrell, Michael I.; Marcacci, Michael; Bravo, Stephen; Kurz, Troy; Tremblay, Jacob; Rusing, Jack C.

2012-01-01

We describe a technique for removing and growing chick embryos in culture that utilizes relatively inexpensive materials and requires little space. It can be readily performed in class by university, high school, or junior high students, and teachers of any grade level should be able to set it up for their students. Students will be able to…

Systematic assessment of blood circulation time of functionalized upconversion nanoparticles in the chick embryo

NASA Astrophysics Data System (ADS)

Nadort, Annemarie; Liang, Liuen; Grebenik, Ekaterina; Guller, Anna; Lu, Yiqing; Qian, Yi; Goldys, Ewa; Zvyagin, Andrei

2015-12-01

Nanoparticle-based delivery of drugs and contrast agents holds great promise in cancer research, because of the increased delivery efficiency compared to `free' drugs and dyes. A versatile platform to investigate nanotechnology is the chick embryo chorioallantoic membrane tumour model, due to its availability (easy, cheap) and accessibility (interventions, imaging). In our group, we developed this model using several tumour cell lines (e.g. breast cancer, colon cancer). In addition, we have synthesized in-house silica coated photoluminescent upconversion nanoparticles with several functional groups (COOH, NH2, PEG). In this work we will present the systematic assessment of their in vivo blood circulation times. To this end, we injected chick embryos grown ex ovo with the functionalized UCNPs and obtained a small amount of blood at several time points after injection to create blood smears The UCNP signal from the blood smears was quantified using a modified inverted microscope imaging set-up. The results of this systematic study are valuable to optimize biochemistry protocols and guide nanomedicine advancement in the versatile chick embryo tumour model.

Dose related shifts in the developmental progress of chick embryos exposed to mobile phone induced electromagnetic fields.

PubMed

Zareen, Nusrat; Khan, Muhammad Yunus; Minhas, Liaqat Ali

2009-01-01

The possible adverse effects of Electromagnetic Fields (EMFs) emitted from mobile phones present a major public concern today. Some studies indicate EMFs effects on genes, free radical production, immunological and carcinogenic effects. On the other hand there are studies which do not support the hypothesis of any biological impacts of EMFs. This study was designed to observe the effects of mobile phone induced EMFs on survival and general growth and development of chick embryo, investigating dose-response relationship if any. This was an experimental study in which developing chick embryos were exposed to different doses of mobile phone induced EMFs. For this purpose a mobile phone was placed in the incubator in the centre of fertilised eggs in silent ringing mode and was 'rung' upon from any other line or cell phone. After incubation for 10 or 15 days the eggs were opened and the developmental mile-stones of the surviving embryos were compared with the non exposed subgroup. EMFs exposure significantly decreased the survivability of the chick embryos. The lower doses of EMFs caused growth retardation. However, this effect of growth retardation reallocated to partial growth enhancement on increasing the dose of EMFs and shifted over to definite growth enhancement on further raising the dose. There is an adverse effect of EMFs exposure on embryo survivability. Chick embryos developmental process is influenced by EMFs. However, these effects are variable depending upon the dose of EMFs exposure.

[A new method for quantitative measurement of the cadmium absorbed by chick embryos].

PubMed

Gottofrey, J

1984-01-01

We attempted to determine the quantity of cadmium incorporated in hens eggs after immersion in cadmium solutions, and the cadmium concentration measured in embryos. We discussed equipment allowing simultaneous treatment of up to 42 samples, and called it " digestor ". It consisted of two gas-heated sand baths, two stands for cooling down solutions and an evacuation system for toxic vapours. Our method was based on wet mineralisation. It consisted of desintegrating experimental chick embryos in a HNO3/H2O2 mixed solution. After heating and evaporating, the quantity of cadmium in the remnant was determined by atomic absorption spectrophotometry. The reliability of such a technique was tested by studying as controls controls 17 days-old chick embryos injected with a known quantity of Cd(NO3). It showed no loss of cadmium. We also compared our procedure with a dry ashing method. The latter showed unacceptable losses and insufficient precision for the problems we wanted to investigate. Our method gave us much more precise results. The equipment we developed has functioned wholly satisfactorily and allowed us to investigate for instance cadmium distribution and concentration in embryonic organs of 17 days-old chicks. It could also be useful for researches concerning other biological samples analyzed for different heavy metals.

Development of the endolymphatic sac in chick embryos, with reference to the degradation of otoconia

NASA Technical Reports Server (NTRS)

Yoshihara, T.; Kaname, H.; Narita, N.; Ishii, T.; Igarashi, M.; Fermin, C. D.

1992-01-01

The endolymphatic sac of chick embryos (from embryonic day 7 to 1-day-old chicks) was studied light- and electron-microscopically. At stage 30-31 (embryonic day 7-7.5), the epithelial cells of the endolymphatic sac were cuboidal to columnar in shape. Microvilli were relatively well developed. The intercellular space was wide. In the endolymphatic space of the endolymphatic sac, varying shapes and sizes of otoconia-like bodies were often observed. Intracytoplasmic phagosomes containing these bodies were rarely found. After stage 37 (embryonic day 11), otoconia-like bodies in the endolymphatic sac decreased in number and size. They were almost the same as the otoconia in the macular organs, ultrastructurally. These findings indicate that the endolymphatic sac of the chick embryos may possess the function of otoconial degradation and removal of calcium from otoconia.

Sulphonated phthalocyanine induced caudal malformative syndrome in the chick embryo.

PubMed

Sandor, S; Prelipceanu, O; Checiu, I

1985-01-01

Sulphonated phthalocyanine (Pht.) has been tested for its possible noxious effect on the developing chick embryo. When injected into the subembryonic cavity of 40-45 hours incubated chick embryos (mainly 10-20 somite pairs), Pht. induces a highly reproducible caudal malformative syndrome (trunk and taillessness, various anomalies of the limbs). The main effect is--in about 15% of the malformed specimens--associated with unilateral microphthalmy and, less frequently, with coelosomy. Microscopically developmental disturbances of the caudal axial organs, of the mesonephros and of the limbs are observed. The initial pathological changes, at microscopic level, are necrosis and hemorrhages in the caudal axial and paraxial area. The allantois is poorly developed or even absent. Skeletal changes involve anomalies of the ribs and of the vertebral column and total or partial absence of the pelvic girdle bones. The high mortality, mainly during the first week, is due--first of all--to the developmental disturbances including the poor development or absence of the allantois. Control experiments with CuCl2 suggest the ethiological role of Cu. Pathogenetic aspects are discussed.

Growth Retardation Of Chick Embryo Exposed To A Low Dose Of Electromagnetic Waves.

PubMed

Siddiqi, Najam; John C, Muthusami; Norrish, Mark; Heming, Thomas

2016-01-01

The objectives of this study were to explore the effects of low dose of the nonionizing (REW) emitted by a mobile phone on the development of chick embryo. one hundred and twenty chick fertilized eggs were equally divided into a control and an exposed group. Sixty fertilized eggs were placed in an egg incubator with a mobile phone (SAR US: 1.10W/kg (head) 0.47 W/kg body) in silent mode having vibration disable mode. Mobile was called for a total of 20 minutes in 24 hours. Twenty embryos each were sacrificed at day 5, 10 and 15, mortality, wet body weight, head to rump length, eye diameter and morphological changes were noted. The control group, 60 eggs were incubated in the same conditions, having removed the phone. No mortality was noted. The experimental group exposed to REW showed subcutaneous haemorrhagic areas and significant growth retardation at day 10 as evidence by smaller eye diameter, wet weight and CR length than the control group. There were no significant growth differences at either day 5 or at day 15. Electromagnetic waves emitted from mobile phones even though for a very short duration of 20 minutes per day have affected the growth of the chick embryo at day 10 of incubation, Hence exposure of these waves are not 100% safe.

The effect of ethanol vapour exposure on atrial and ventricular walls of chick embryos.

PubMed

Kamran, Kiran; Khan, Muhammad Yunus; Minhas, Liaqat Ali

2016-10-01

To study the effects of ethanol vapour exposure on atrial and ventricular walls of heart in chick embryo. The study design was experimental, conducted at Islamabad Centre of College of Physicians and Surgeons, Pakistan. One hundred and eighty chicken eggs were divided into two groups, experimental and control, of 90 eggs each. Each group was subdivided into three subgroups of 30 eggs each based on the day of sacrifice. Experimental group was exposed to ethanol vapours and then compared with age matched controls. The thickness of atrial and ventricular walls along with lengths of valvular cusps increased in hearts of day 7 and day 10 chick embryos in experimental group. There was thinning of walls and decreased length of valvular cusps in hearts of experimental chicks on hatching as compared to age matched controls. Ethanol vapour exposure during development causes cardiac and septal wall thickening during initial days of development followed by cardiac and septal wall thinning which is a classical picture of alcohol induced cardiomyopathies.

Effects of antibodies to EG-VEGF on angiogenesis in the chick embryo chorioallantoic membrane.

PubMed

Feflea, Stefana; Cimpean, Anca Maria; Ceausu, Raluca Amalia; Gaje, Pusa; Raica, Marius

2012-01-01

Endocrine gland-related vascular endothelial growth factor (EG-VEGF), is an angiogenic factor specifically targeting endothelial cells derived from endocrine tissues. The inhibition of the EG-VEGF/prokineticin receptor pathway could represent a selective antiangiogenic and anticancer strategy. to evaluate the impact of an antibody to EG-VEGF on the rapidly growing capillary plexus of the chick embryo chorioallantoic membrane (CAM). The in ovo CAM assay was performed for the humanized EG-VEGF antibody. Hemorrhagic damage was induced in the capillaries, which led to early death of the embryos. Upon morphological staining, there was evidence of vascular disruption and extravasation of red blood cells in the chorion. Signs of vacuolization of the covering epithelium were also observed. Blocking endogenous EG-VEGF might represent a valuable approach of impairing or inhibiting angiogenesis in steroidogenic-derived embryonic tissues.

Morphogenesis and calcification of the statoconia in the chick (Gallus domesticus) embryo - Implications for future studies

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Igarashi, M.

1985-01-01

The morphogenesis of the statoconia in the chick, Gallus domesticus, injected with a carbon anhydrase inhibitor is studied. The preparation of the embryo specimens for analysis is described. The early, middle, and late stages of embryonic development are examined. The data reveal that acetozolamide inhibits statoconia formation in the middle stage of development and the calcification process follows statoconia formation. The spatial relationship between the development of type 1 and type 2 hair cells and the appearance and maturation of the statoconia is investigated.

Effect of antithyroid drug on chick embryos during the last week of development: delayed hatching and decreased cerebellar acetylcholinesterase activity.

PubMed

Haba, Gen; Nishigori, Hidekazu; Tezuka, Yu; Kagami, Keisuke; Sugiyama, Toru; Nishigori, Hideo

2011-11-01

Hypothyroid state during embryogenesis disturbs normal growth and brain development, influencing later life. To evaluate the harmful consequences of the state during embryogenesis using an animal model, we inhibited thyroid hormone biosynthesis in chick embryos by using methimazole (MMI). Typically, embryos were treated with MMI (20 µmol/egg) on day 14, and examined on specific days.  Of the control embryos, 94% hatched on day 21, whereas 0% and 60% of MMI-treated embryos hatched on days 21 and 24, respectively. MMI retarded the rates of bodyweight gain as well as liver and heart development, and delayed hatching. However, the external differences in appearance and differences in the weights of the newly hatched control chicks on day 21 and the MMI-treated chicks on day 24 were less obvious. Embryos treated with MMI exhibited increased mass in their brain parts on day 24. Most notably, the treatment resulted in a 1.35-fold increase in cerebellum weight compared to that of the untreated animals. Acetylcholinesterase activity in the cerebellum on the day of hatching decreased significantly to 0.85-fold that of the untreated controls. Thyroid hormone receptor β mRNA was detected from day 12 and dramatically expressed from day 19 to the day of hatching. The 'fertilized hen's egg-chick embryo-chick system' is an appropriate animal model for investigating the hypothyroid state during embryogenesis. Decreased cerebellar acetylcholinesterase activity after MMI treatment was assumed to relate to a mechanism of motor and cognitive deficits in congenital hypothyroidism. © 2011 The Authors. Journal of Obstetrics and Gynaecology Research © 2011 Japan Society of Obstetrics and Gynecology.

Neurologic illness following post-exposure prophylaxis with purifiled chick embryo cell antirabies vaccine.

PubMed

Chakravarty, A

2001-09-01

Clinical details of a neurologic illness simultating Guillain Barre syndrome developing in a patient after post-exposure prophylaxis with purified chick embryo cell (PCEC) anti-rabies vaccine is reported. Neurologic complication following PCEC vaccination has not been reported earlier.

The gga-let-7 family post-transcriptionally regulates TGFBR1 and LIN28B during the differentiation process in early chick development.

PubMed

Lee, Sang In; Jeon, Mi-Hyang; Kim, Jeom Sun; Jeon, Ik-Soo; Byun, Sung June

2015-12-01

Early chick embryogenesis is governed by a complex mechanism involving transcriptional and post-transcriptional regulation, although how post-transcriptional processes influence the balance between pluripotency and differentiation during early chick development have not been previously investigated. Here, we characterized the microRNA (miRNA) signature associated with differentiation in the chick embryo, and found that as expression of the gga-let-7 family increases through early development, expression of their direct targets, TGFBR1 and LIN28B, decreases; indeed, gga-let-7a-5p and gga-let-7b miRNAs directly bind to TGFBR1 and LIN28B transcripts. Our data further indicate that TGFBR1 and LIN28B maintain pluripotency by regulating POUV, NANOG, and CRIPTO. Therefore, gga-let-7 miRNAs act as post-transcriptional regulators of differentiation in blastodermal cells by repressing the expression of the TGFBR1 and LIN28B, which intrinsically controls blastodermal cell differentiation in early chick development. © 2015 Wiley Periodicals, Inc.

Induction of metallothionein in chick embryos as a mechanism of tolerance to platinum group metal exposure.

PubMed

Gagnon, Zofia E; Patel, Amit

2007-02-15

Recent data show that platinum group metals (PGMs), primarily platinum (Pt), palladium (Pd) and rhodium (Rd), from automobile catalytic converters are being deposited in the environment. We investigated the PGM neurotoxicity and tolerance mechanism by induction of metallothionein (MT) in developing chick embryos. Chick embryos were injected on the 7th and 14th days of incubation with different concentrations of Pt and mixture of Pt, Pd and Rh (PGM mix) solutions. It is documented that induction of MT by zinc (Zn+2) protects against metal and non-metal hepatotoxicity. In this study the MT induction was examined through pretreatment of the two highest Pt(IV) exposure levels with exogenous Zn2+ on the 4th and 11th days of incubation. SDS-PAGE assay and digital image system were used to identify and quantify MT in homogenized brain and liver tissues. Quantitative analysis revealed an increase of MT in the 5 ppm Pt exposure as compared to controls. The 10 ppm Pt treatment was a lethal dose for exposed embryos. There was increased mortality at the 1.0 PGM mix level. The interaction of Pt, Pd and Rh in the mixture seems to favor metal accumulation and MT induction in the liver but not the brain. Pretreatment with exogenous Zn2+ increased chick survival. These results indicate that induction of MT plays a protective role against PGM toxicity. Metal analysis using atomic absorption spectrometer in graphite furnace mode (GFAAS) revealed PGM accumulation in chick embryo liver and brain tissues proportional to exposure concentration. Our results may imply that MT has an important role as a tolerance mechanism against PGM toxicity. The presence of Pt(IV) in brain tissue suggests that the undeveloped blood-brain barrier is permeable to PGMs. This raises concerns regarding the implication of these metals on neural injury.

Simultaneous Growth of Rabies and Canine Distemper Viruses in Chick Embryos

PubMed Central

Chang, James C. C.

1965-01-01

Rabies virus and canine distemper virus were grown simultaneously, and possibly symbiotically, in the same chick embryos. There seemed to be no adverse effect on either virus when cultured in such manner. Bivalent vaccines for rabies and canine distemper were produced. The potencies and the virus titers of such vaccines were comparable to those of rabies vaccine and canine distemper vaccine produced separately. PMID:14290942

Atg7-Mediated Autophagy Is Involved in the Neural Crest Cell Generation in Chick Embryo.

PubMed

Wang, Guang; Chen, En-Ni; Liang, Chang; Liang, Jianxin; Gao, Lin-Rui; Chuai, Manli; Münsterberg, Andrea; Bao, Yongping; Cao, Liu; Yang, Xuesong

2018-04-01

Autophagy plays a very important role in numerous physiological and pathological events. However, it still remains unclear whether Atg7-induced autophagy is involved in the regulation of neural crest cell production. In this study, we found the co-location of Atg7 and Pax7 + neural crest cells in early chick embryo development. Upregulation of Atg7 with unilateral transfection of full-length Atg7 increased Pax7 + and HNK-1 + cephalic and trunk neural crest cell numbers compared to either Control-GFP transfection or opposite neural tubes, suggesting that Atg7 over-expression in neural tubes could enhance the production of neural crest cells. BMP4 in situ hybridization and p-Smad1/5/8 immunofluorescent staining demonstrated that upregulation of Atg7 in neural tubes suppressed the BMP4/Smad signaling, which is considered to promote the delamination of neural crest cells. Interestingly, upregulation of Atg7 in neural tubes could significantly accelerate cell progression into the S phase, implying that Atg7 modulates cell cycle progression. However, β-catenin expression was not significantly altered. Finally, we demonstrated that upregulation of the Atg7 gene could activate autophagy as did Atg8. We have also observed that similar phenotypes, such as more HNK-1 + neural crest cells in the unilateral Atg8 transfection side of neural tubes, and the transfection with full-length Atg8-GFP certainly promote the numbers of BrdU + neural crest cells in comparison to the GFP control. Taken together, we reveal that Atg7-induced autophagy is involved in regulating the production of neural crest cells in early chick embryos through the modification of the cell cycle.

The impact of high-salt exposure on cardiovascular development in the early chick embryo.

PubMed

Wang, Guang; Zhang, Nuan; Wei, Yi-Fan; Jin, Yi-Mei; Zhang, Shi-Yao; Cheng, Xin; Ma, Zheng-Lai; Zhao, Shu-Zhu; Chen, You-Peng; Chuai, Manli; Hocher, Berthold; Yang, Xuesong

2015-11-01

In this study, we show that high-salt exposure dramatically increases chick mortality during embryo development. As embryonic mortality at early stages mainly results from defects in cardiovascular development, we focused on heart formation and angiogenesis. We found that high-salt exposure enhanced the risk of abnormal heart tube looping and blood congestion in the heart chamber. In the presence of high salt, both ventricular cell proliferation and apoptosis increased. The high osmolarity induced by high salt in the ventricular cardiomyocytes resulted in incomplete differentiation, which might be due to reduced expression of Nkx2.5 and GATA4. Blood vessel density and diameter were suppressed by exposure to high salt in both the yolk sac membrane (YSM) and chorioallantoic membrane models. In addition, high-salt-induced suppression of angiogenesis occurred even at the vasculogenesis stage, as blood island formation was also inhibited by high-salt exposure. At the same time, cell proliferation was repressed and cell apoptosis was enhanced by high-salt exposure in YSM tissue. Moreover, the reduction in expression of HIF2 and FGF2 genes might cause high-salt-suppressed angiogenesis. Interestingly, we show that high-salt exposure causes excess generation of reactive oxygen species (ROS) in the heart and YSM tissues, which could be partially rescued through the addition of antioxidants. In total, our study suggests that excess generation of ROS might play an important role in high-salt-induced defects in heart and angiogenesis. © 2015. Published by The Company of Biologists Ltd.

Secretion pathway of liver IGF-1 via JAK2/STAT3 in chick embryo under the monochromatic light.

PubMed

Wang, Tuanjie; Dong, Yulan; Wang, Zixu; Cao, Jing; Chen, Yaoxing

2016-02-01

This study reveals mechanism of monochromatic light on the IGF-1 secretion of chick embryo liver. The chick embryos were incubated and exposed to continuous red, green, blue light or a dark environment. Compared to other light-treated groups, green light increased IGF-1 and melatonin concentrations both in plasma and liver, and Mel1a, Mel1b and Mel1c receptors expressions in liver but decreased p-JAK2, p-STAT3 and ROS in liver. IGF-1 had a positive correlation with melatonin, but a negative relevance with p-JAK2 and p-STAT3. In vitro, the IGF-1 level in the hepatocyte supernatant was enhanced by melatonin with lower p-JAK2/p-STAT3 and ROS levels, which was suppressed by Mel1c antagonist but not Mel1a/Mel1b or Mel1b antagonists. AG490 (JAK/STAT inhibitor) promoted role of melatonin-Mel1c modulated IGF-1 secretion. These results suggest the antioxidant effect of melatonin mediated the green light-enhanced IGF-1 secretion of chick embryo liver through Mel1c receptor to inhibit the JAK2/STAT3 pathway.

In vivo marking of single cells in chick embryos using photoactivation of GFP.

PubMed

Stark, D A; Kulesa, P M

2005-10-01

Selective marking of a single cell within a living embryo is often difficult due to the inaccuracy and invasiveness of standard techniques. This unit describes a minimally invasive optical protocol that uses 405-nm laser light to photoactivate a variant of green fluorescent protein (PAGFP). This method takes advantage of the accessibility of the chick embryo to inject PAGFP into a region of interest and uses electroporation to deliver the construct into cells. This unit describes in detail how single and small groups of cells (n<10) that express PAGFP can be made visually distinguishable from the host population using the photoactivation process. Included is a means to maximize the fluorescence increase due to photoactivated GFP signal and to reduce photobleaching. Briefly outlined are previously developed chick culture and time-lapse imaging techniques to allow for the subsequent monitoring of photoactivated cell migratory behaviors. The technique has the potential to be a less-invasive, accurate tool for in vivo studies that involve following cell lineage and cell migration.

Embryotoxic effects of crude oil in mallard ducks and chicks

USGS Publications Warehouse

Hoffman, David J.

1978-01-01

Recent studies in this laboratory have revealed that surface applications of microliter amounts of some crude and fuel oils that coat less than 10% of the egg surface reduce hatching considerably in different avian species. Applications of paraffin compounds that coat equal areas of the egg surface do not reduce hatching suggesting that toxicity is due to causes other than asphyxia. In the present study, 1–10 μl of South Louisiana crude oil, an API reference oil, were applied to the surface of fertile mallard (Anas platyrhynchos) and chicken (Gallus gallus) eggs. Early embryolethality was greater in mallard embryos than in chick embryos, but later embryolethality that coincided with the time of rapid outgrowth of the chorioallantoic membrane was more prevalent in chick embryos. The overall incidence of embryolethality was similar in both species. Retardation of growth as reflected by embryonic body weight, crown-rump length, beak length, and general appearance was more pronounced in chick than mallard embryos. Teratogenic defects were more frequent in chick embryos, and incomplete or abnormal ossification of the skull was the most common. External application of equivalent amounts of a mixture of paraffin compounds present in crude oil had virtually no embryotoxic effects in either species, suggesting that other components including aromatic hydrocarbons and organometallics may cause the embryotoxicity.

Microwave effects on isolated chick embryo hearts

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

Caddemi, A.; Tamburello, C.C.; Zanforlin, L.

1986-01-01

This study was designed to examine the effects of microwaves on the electric activity of hearts as a means of elucidating interactive mechanisms of nonionizing radiation with cardiac tissue. Experiments were performed on isolated hearts of 9-12-day-old chick embryos placed in small petri dishes. Oxygenated isotonic Ringer's solution at 37 degrees C permitted heart survival. Samples were irradiated at 2.45 GHz with a power density of 3 mW/cm2. The heart signal was detected with a glass micropipet inserted into the sinoatrial node and examined by means of a Berg-Fourier analyzer. Pulsed microwaves caused the locking of the heartbeat to themore » modulation frequency, whereas continuous wave irradiation might have induced slight bradycardia. Pulsed fields induced stimulation or regularization of the heartbeat in arrhythmia, fibrillation, or arrest of the heart.« less

Effects of posture on the respiratory mechanics of the chick embryo.

PubMed

Menna, Tara M; Mortola, Jacopo P

2002-10-01

In the chicken embryo, pulmonary ventilation and pulmonary gas exchange begin approximately one day before the completion of hatching. We asked to what extent the posture inside the egg, and the presence of the eggshell and membranes, may alter the mechanical behaviour of the respiratory system. The passive mechanical properties of the respiratory system were studied in chicken embryos during the internal pipping phase (rupture of the air cell) or the external pipping phase (hole in the eggshell). Tracheal pressure and changes in lung volume were recorded during mechanical ventilation, first, with the embryo curled up inside the egg, then again after exteriorization from the eggshell. In the internal pippers, respiratory system compliance increased and expiratory resistance decreased after exteriorization, whereas the mean inspiratory impedance did not change. In the external pippers, exteriorization had no significant effects on respiratory compliance, resistance, or impedance, and the values were similar to those of newly hatched chicks. We conclude that, in the chicken embryo, at a time when pulmonary ventilation becomes an important mechanism for gas exchange, the curled up posture inside the egg does not provide any significant mechanical constraint to breathing.

Short periods of incubation, egg turning during storage and broiler breeder hens age for early development of embryos, hatching results, chicks quality and juvenile growth.

PubMed

Damaziak, K; Paweska, M; Gozdowski, D; Niemiec, J

2018-05-14

An effect of modification of storage conditions of the eggs of broiler breeder flocks at the age of 49-, 52- and 70-, 73-wks of life on an early embryonic development, hatching time and synchronization, hatchability rates, chicks quality and broiler growth was investigated. The eggs were divided into 4 experimental groups: COI = eggs storage 5 d, at turning every 12 h; NSP = eggs storage 12 d, at turning every 12 h; SPIDES = were treated with 4 h pre-incubation at 30°C and 50-55% air humidity, delivered at 5 and 10 d over of 12 d of storage, and turning every 12 h; NCOI = eggs storage 12 d, no turning and no pre-incubation. Eggs from older hens were characterized by poorer hatchability and poorer chicks quality. The use of 2 × 4 h pre-incubation in 12 d of eggs storage could have an effect on the initial acceleration of embryonic development in eggs of young hens, contributing to the alignment of embryos development in eggs from young and older hens to 72 h of incubation. Pre-incubation had no effect on the length of incubation period, hatching window, but it increased the hatchability of the set and apparently fertilized eggs and decreased the number of eggs not hatched, and also improved chicks quality. Eggs turning by 90° every 12 h during the storage positively affected the embryonic development, shortening the incubation time and the quality of chicks, but had no effect on hatchability rates and body weight in 42 d of life. Based on the obtained results, it can be concluded that the applied modifications can be effective in counteracting the negative effects of storage of hatching eggs from both young and older birds.

Respiratory gas exchange of high altitude adapted chick embryos

NASA Technical Reports Server (NTRS)

Wangensteen, O. D.; Rahn, H.; Burton, R. R.; Smith, A. H.

1974-01-01

Study of gas exchange by embryos from chickens acclimatized to an altitude of 3800 m. The oxygen partial pressure and carbon dioxide partial pressure differences across the egg shell were measured and found to be less than the values previously reported for sea-level eggs by about a factor of two. Further measurements of embryonic oxygen consumption and shell conductivity to oxygen indicated that, compared to eggs at sea level, oxygen consumption was reduced by a factor of 0.58 while conductivity to oxygen was increased only by a factor of 1.07 in the high-altitude eggs. These independent measurements predict the change in oxygen partial pressure across the egg shell of the high-altitude eggs to be only 0.54 times that of sea-level eggs; the directly measured factor was 0.53. The authors conclude that at high altitude, a major adaptation of the chick embryo is a reduced metabolism which decreases the change in oxygen partial pressure across the egg shell since its gas conductivity remains essentially unchanged.

Dual labeling of neural crest cells and blood vessels within chicken embryos using Chick(GFP) neural tube grafting and carbocyanine dye DiI injection.

PubMed

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J

2015-05-28

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chick(GFP) embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. Chick(GFP)-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system.

Dual Labeling of Neural Crest Cells and Blood Vessels Within Chicken Embryos Using ChickGFP Neural Tube Grafting and Carbocyanine Dye DiI Injection

PubMed Central

Delalande, Jean-Marie; Thapar, Nikhil; Burns, Alan J.

2015-01-01

All developing organs need to be connected to both the nervous system (for sensory and motor control) as well as the vascular system (for gas exchange, fluid and nutrient supply). Consequently both the nervous and vascular systems develop alongside each other and share striking similarities in their branching architecture. Here we report embryonic manipulations that allow us to study the simultaneous development of neural crest-derived nervous tissue (in this case the enteric nervous system), and the vascular system. This is achieved by generating chicken chimeras via transplantation of discrete segments of the neural tube, and associated neural crest, combined with vascular DiI injection in the same embryo. Our method uses transgenic chickGFP embryos for intraspecies grafting, making the transplant technique more powerful than the classical quail-chick interspecies grafting protocol used with great effect since the 1970s. ChickGFP-chick intraspecies grafting facilitates imaging of transplanted cells and their projections in intact tissues, and eliminates any potential bias in cell development linked to species differences. This method takes full advantage of the ease of access of the avian embryo (compared with other vertebrate embryos) to study the co-development of the enteric nervous system and the vascular system. PMID:26065540

Chick embryogenesis: a unique platform to study the effects of environmental factors on embryo development.

PubMed

Yahav, S; Brake, J

2014-01-01

. Manipulating environmental temperature during the period of egg storage, during the intermediate pre-incubation period, and incubation period per se has been found to significantly affect embryo development, hatching progress, chick quality at hatching, and chick development post-hatching. These temperature manipulations have also been shown to affect the acquisition of thermotolerance to subsequent post-hatching thermal challenge. This chapter will focus on: a. "maternal effects" on embryo and post-hatching development; b. environmental effects during the post-ovipositional period of egg storage, the intermediate pre-incubation period, and incubation period per se on chick embryogenesis and subsequent post-hatching growth and development; and c. effects of temperature manipulations during the pre-incubation and incubation periods on acquisition of thermotolerance and development of secondary sexual characteristics in broiler chickens.

Effect of Radiofrequency Radiation Emitted from 2G and 3G Cell Phone on Developing Liver of Chick Embryo - A Comparative Study.

PubMed

D'Silva, Mary Hydrina; Swer, Rijied Thompson; Anbalagan, J; Rajesh, Bhargavan

2017-07-01

The increasing scientific evidence of various health hazards on exposure of Radiofrequency Radiation (RFR) emitted from both the cell phones and base stations have caused significant media attention and public discussion in recent years. The mechanism of interaction of RF fields with developing tissues of children and fetuses may be different from that of adults due to their smaller physical size and variation in tissue electromagnetic properties. The present study may provide an insight into the basic mechanisms by which RF fields interact with developing tissues in an embryo. To evaluate the possible tissue and DNA damage in developing liver of chick embryo following chronic exposure to Ultra-High Frequency/Radiofrequency Radiation (UHF/RFR) emitted from 2G and 3G cell phone. Fertilized chick embryos were incubated in four groups. Group A-experimental group exposed to 2G radiation (60 eggs), Group B- experimental group exposed to 3G radiation (60 eggs), Group C- sham exposed control group (60 eggs) and Group D- control group (48 eggs). On completion of scheduled duration, the embryos were collected and processed for routine histological studies to check structural changes in liver. The nuclear diameter and karyorrhexis changes of hepatocytes were analysed using oculometer and square reticule respectively. The liver procured from one batch of eggs from all the four groups was subjected to alkaline comet assay technique to assess DNA damage. The results were compared using one-way ANOVA test. In our study, the exposure of developing chick embryos to 2G and 3G cell phone radiations caused structural changes in liver in the form of dilated sinusoidal spaces with haemorrhage, increased vacuolations in cytoplasm, increased nuclear diameter and karyorrhexis and significantly increased DNA damage. The chronic exposure of chick embryo liver to RFR emitted from 2G and 3G cell phone resulted in various structural changes and DNA damage. The changes were more pronounced in 3

Fostering efficacy and toxicity evaluation of traditional Chinese medicine and natural products: Chick embryo as a high throughput model bridging in vitro and in vivo studies.

PubMed

Wu, Tong; Yu, Gui-Yuan; Xiao, Jia; Yan, Chang; Kurihara, Hiroshi; Li, Yi-Fang; So, Kwok-Fai; He, Rong-Rong

2018-04-19

Efficacy and safety assessments are essential thresholds for drug candidates from preclinical to clinical research. Conventional mammalian in vivo models cannot offer rapid pharmacological and toxicological screening, whereas cell-based or cell-free in vitro systems often lead to inaccurate results because of the lack of physiological environment. Within the avian species, gallus gallus is the first bird to have its genome sequencing. Meantime, chick embryo is an easily operating, relatively transparent and extensively accessible model, whose physiological and pathological alterations can be visualized by egg candler, staining and image technologies. These features facilitate chick embryo as a high-throughput screening platform bridging in vivo and in vitro gaps in the pharmaceutical research. Due to the complicated ingredients and multiple-targets natures of traditional Chinese medicine (TCM), testing the efficacy and safety of TCM by in vitro methods are laborious and inaccurate, while testing in mammalian models consume massive cost and time. As such, the productive living organism chick embryo serves as an ideal biological system for pharmacodynamics studies of TCM. Herein, we comprehensively update recent progresses on the specialty of chick embryo in evaluation of efficacy and toxicity of drugs, with special concerns of TCM. Copyright © 2018 Elsevier Ltd. All rights reserved.

High glucose environment inhibits cranial neural crest survival by activating excessive autophagy in the chick embryo

PubMed Central

Wang, Xiao-Yu; Li, Shuai; Wang, Guang; Ma, Zheng-Lai; Chuai, Manli; Cao, Liu; Yang, Xuesong

2015-01-01

High glucose levels induced by maternal diabetes could lead to defects in neural crest development during embryogenesis, but the cellular mechanism is still not understood. In this study, we observed a defect in chick cranial skeleton, especially parietal bone development in the presence of high glucose levels, which is derived from cranial neural crest cells (CNCC). In early chick embryo, we found that inducing high glucose levels could inhibit the development of CNCC, however, cell proliferation was not significantly involved. Nevertheless, apoptotic CNCC increased in the presence of high levels of glucose. In addition, the expression of apoptosis and autophagy relevant genes were elevated by high glucose treatment. Next, the application of beads soaked in either an autophagy stimulator (Tunicamycin) or inhibitor (Hydroxychloroquine) functionally proved that autophagy was involved in regulating the production of CNCC in the presence of high glucose levels. Our observations suggest that the ERK pathway, rather than the mTOR pathway, most likely participates in mediating the autophagy induced by high glucose. Taken together, our observations indicated that exposure to high levels of glucose could inhibit the survival of CNCC by affecting cell apoptosis, which might result from the dysregulation of the autophagic process. PMID:26671447

A homeobox gene involved in node, notochord and neural plate formation of chick embryos.

PubMed

Stein, S; Kessel, M

1995-01-01

We have isolated a chicken cDNA clone, Cnot, resembling in sequence and expression pattern the Xenopus homeobox gene Xnot. The major, early transcription domains of Cnot are the node, the notochord and prenodal and postnodal neural plate caudal from the prospective hindbrain level. All these cell populations appear to be descendants of the Cnot-expressing cells of the node, suggesting a cell lineage relationship. After the onset of somitogenesis, a second, independent expression domain appears in the neural folds at the prospective mid- and forebrain levels, and further transcripts are found in the epiphysis, the ventral diencephalon, the preoral gut and the limb buds. Transplantation of nodes from extended streak embryos leads to the formation of ectopic notochords, which express Cnot in the typical, cranially decreasing gradient. Transplantation of young nodes to young hosts has previously been described to induce secondary embryos. We observed that secondary chick embryos express Cnot in node derived, notochord-like structures and in the anterior neural plate, similar to the domains seen in primary embryos. However, expression was absent from the posterior neural plate, which in the induction experiments is excluded from the node lineage. This finding corroborates our initial conclusion about a cell lineage relationship between node, notochord, and neural plate defined by Cnot expression. The midline mesoderm of vertebrate embryos consists of two tissues, the prechordal mesoderm and the notochord. The anterior notochord, the head process, may represent an intermediate form. The transition from prechordal to chordal mesoderm can be followed by the expression of the two marker homeobox genes goosecoid and Cnot, first in the primitive streak, and then in the head process. We suggest that expression of goosecoid or Cnot is involved in the specification of a prechordal or notochordal identity, respectively. A transition from goosecoid to Cnot expression may proceed

The Effect of Levetiracetam on Closure of the Midline in Early Chicken Embryos.

PubMed

Ozgural, Onur; Armagan, Ercan; Bozkurt, Melih; Eroglu, Umit; Kahilogullari, Gokmen; Unlu, Agahan

2015-01-01

Genetic predisposition and some environmental factors play an important role in the development of neural tube defects. Levetiracetam is a new drug that has been approved in the treatment of partial seizures. We aimed in this study to determine the effect of levetiracetam on chick embryos. One hundred and sixty fertile non-pathogenic Super Nick eggs were incubated for 24 hours and were divided into four groups of 40 eggs each. Levetiracetam was administered via the sub-blastodermic route. The eggs were incubated for another 24 hours. All eggs were opened at the 48th hour, and the embryos were evaluated morphologically and histopathologically. The effects of levetiracetam on the embryo were correlated with the dose of levetiracetam. In the light of the results, it was determined that the use of increasing doses of levetiracetam led to defects of midline closure in early chicken embryos. Levetiracetam, a new antiepileptic drug that is effective especially on calcium ion concentration, leads to defects in midline closure in embryos in a dose-dependent manner. Further studies are needed to show the mechanism of embryonic damage and the mechanisms of its teratogenous effects associated with genetic and environmental factors.

Significance of chick quality score in broiler production.

PubMed

van de Ven, L J F; van Wagenberg, A V; Uitdehaag, K A; Groot Koerkamp, P W G; Kemp, B; van den Brand, H

2012-10-01

The quality of day old chicks is crucial for profitable broiler production, but a difficult trait to define. In research, both qualitative and quantitative measures are used with variable predictive value for subsequent performance. In hatchery practice, chick quality is judged on a binomial scale, as chicks are divided into first grade (Q1-saleable) and second grade (Q2) chicks right after hatch. Incidences and reasons for classifying chicks as Q2, and potential of these chicks for survival and post-hatch performance have hardly been investigated, but may provide information for flock performance. We conducted an experiment to investigate (1) the quality of a broiler flock and the relation with post-hatch flock performance based on a qualitative score (Pasgar©score) of Q1 chicks and based on the incidence of Q2 chicks and (2) the reasons for classifying chicks as Q2, and the potential of these chicks for survival and post-hatch growth. The performance was followed of Q1 and Q2 chicks obtained from two breeder flocks that hatched in two different hatching systems (a traditional hatcher or a combined hatching and brooding system, named Patio). Eggs were incubated until embryo day 18, when they were transferred to one of the two hatching systems. At embryo day 21/post-hatch day 0, all chicks from the hatcher (including Q2 chicks) were brought to Patio, where the hatchery manager marked the Q2 chicks from both flocks and hatching systems and registered apparent reasons for classifying these chicks as Q2. Chick quality was assessed of 100 Q1 chicks from each flock and hatching system. Weights of all chicks were determined at days 0, 7, 21 and 42. There were no correlations between mean Pasgar©score and post-hatch growth or mortality, and suboptimal navel quality was the only quality trait associated with lower post-hatch growth. Growth was clearly affected by breeder flock and hatching system, which could not be linked to mean Pasgar©score or incidence of Q2 chicks

The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

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

Aygün, Ali, E-mail: aaygun@selcuk.edu.tr; Narinç, Doğan, E-mail: narincd@gmail.com

Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55%more » relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.« less

The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

NASA Astrophysics Data System (ADS)

Aygün, Ali; Narinç, Doǧan

2016-04-01

Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

Prenatal opiate withdrawal activates the chick embryo hypothalamic pituitary-adrenal axis and dilates vitelline blood vessels via serotonin(2) receptors.

PubMed

Schrott, Lisa M; Baumgart, Mary Irene; Zhang, Xuewei; Sparber, Sheldon B

2002-10-01

Opiate withdrawal during pregnancy may occur because of voluntary or forced detoxification, or from rapid cycling associated with exposure to short-acting "street" opiates. Thus, animal modeling of prenatal withdrawal and development of potential therapeutic interventions is important. Direct developmental effects of opiates and/or withdrawal can be studied using a chick model. In ovo administration of the long-acting opiate N-desmethyl-l-alpha-noracetylmethadol (NLAAM) induces opiate dependence in the chick embryo. We examined activation of the hypothalamic-pituitary-adrenal (HPA) axis (assessed via serum corticosterone) and hemodynamic changes (assessed as changes in apparent diameter of vitelline (extraembryonic) blood vessels) after chronic NLAAM exposure and naloxone (Nx)-precipitated withdrawal during late stages of embryogenesis. Nx-precipitated withdrawal increased corticosterone 2- to 4.5-fold and diameters of vitelline blood vessels by 15 to 45%. NLAAM exposure itself did not effect these measures. In a second set of experiments, isobutylmethylxanthine (IBMX), a phosphodiesterase inhibitor, was injected into eggs with embryos. IBMX similarly increased corticosterone and vitelline vessel diameter, with a similar time course and response magnitude. Previous studies found that serotonin(2) (5-HT(2)) receptors were involved in other withdrawal manifestations, so we determined whether they were likewise involved. Pretreatment with the 5-HT(2) antagonist ritanserin completely blocked HPA axis activation and vasodilation associated with both Nx-precipitated withdrawal and IBMX administration. This indicates that 5-HT(2) receptors, directly or indirectly, mediate these withdrawal manifestations in the chick embryo.

The chick embryo: a leading model in somitogenesis studies.

PubMed

Pourquié, Olivier

2004-09-01

The vertebrate body is built on a metameric organization which consists of a repetition of functionally equivalent units, each comprising a vertebra, its associated muscles, peripheral nerves and blood vessels. This periodic pattern is established during embryogenesis by the somitogenesis process. Somites are generated in a rhythmic fashion from the presomitic mesoderm and they subsequently differentiate to give rise to the vertebrae and skeletal muscles of the body. Somitogenesis has been very actively studied in the chick embryo since the 19th century and many of the landmark experiments that led to our current understanding of the vertebrate segmentation process have been performed in this organism. Somite formation involves an oscillator, the segmentation clock whose periodic signal is converted into the periodic array of somite boundaries by a spacing mechanism relying on a traveling threshold of FGF signaling regressing in concert with body axis extension.

The generation of vertebral segmental patterning in the chick embryo

PubMed Central

Senthinathan, Biruntha; Sousa, Cátia; Tannahill, David; Keynes, Roger

2012-01-01

We have carried out a series of experimental manipulations in the chick embryo to assess whether the notochord, neural tube and spinal nerves influence segmental patterning of the vertebral column. Using Pax1 expression in the somite-derived sclerotomes as a marker for segmentation of the developing intervertebral disc, our results exclude such an influence. In contrast to certain teleost species, where the notochord has been shown to generate segmentation of the vertebral bodies (chordacentra), these experiments indicate that segmental patterning of the avian vertebral column arises autonomously in the somite mesoderm. We suggest that in amniotes, the subdivision of each sclerotome into non-miscible anterior and posterior halves plays a critical role in establishing vertebral segmentation, and in maintaining left/right alignment of the developing vertebral elements at the body midline. PMID:22458512

Effect of Radiofrequency Radiation Emitted from 2G and 3G Cell Phone on Developing Liver of Chick Embryo – A Comparative Study

PubMed Central

Swer, Rijied Thompson; Anbalagan, J.; Rajesh, Bhargavan

2017-01-01

Introduction The increasing scientific evidence of various health hazards on exposure of Radiofrequency Radiation (RFR) emitted from both the cell phones and base stations have caused significant media attention and public discussion in recent years. The mechanism of interaction of RF fields with developing tissues of children and fetuses may be different from that of adults due to their smaller physical size and variation in tissue electromagnetic properties. The present study may provide an insight into the basic mechanisms by which RF fields interact with developing tissues in an embryo. Aim To evaluate the possible tissue and DNA damage in developing liver of chick embryo following chronic exposure to Ultra-High Frequency/Radiofrequency Radiation (UHF/RFR) emitted from 2G and 3G cell phone. Materials and Methods Fertilized chick embryos were incubated in four groups. Group A-experimental group exposed to 2G radiation (60 eggs), Group B- experimental group exposed to 3G radiation (60 eggs), Group C- sham exposed control group (60 eggs) and Group D– control group (48 eggs). On completion of scheduled duration, the embryos were collected and processed for routine histological studies to check structural changes in liver. The nuclear diameter and karyorrhexis changes of hepatocytes were analysed using oculometer and square reticule respectively. The liver procured from one batch of eggs from all the four groups was subjected to alkaline comet assay technique to assess DNA damage. The results were compared using one-way ANOVA test. Results In our study, the exposure of developing chick embryos to 2G and 3G cell phone radiations caused structural changes in liver in the form of dilated sinusoidal spaces with haemorrhage, increased vacuolations in cytoplasm, increased nuclear diameter and karyorrhexis and significantly increased DNA damage. Conclusion The chronic exposure of chick embryo liver to RFR emitted from 2G and 3G cell phone resulted in various structural

Effects of maternal dietary manganese and incubation temperature on hatchability, antioxidant status, and expression of heat shock proteins in chick embryos.

PubMed

Zhu, Y W; Lu, L; Li, W X; Zhang, L Y; Ji, C; Lin, X; Liu, H C; Odle, J; Luo, X G

2015-12-01

To investigate whether supplementing manganese (Mn) to the maternal diet could reduce the deleterious effect of heat stress on the developing embryo, the hatchability, antioxidant status, and expression of heat shock proteins (HSP) were evaluated in chick embryos under normal and high incubation temperatures. A completely randomized design ( = 6) with 2 maternal dietary Mn treatments (unsupplemented control basal diet versus the basal diet + 120 mg Mn/kg as inorganic Mn) × 2 incubation temperatures (normal, 37.8°C, versus high, 39.0°C) was used. High incubation temperature did not affect ( > 0.19) hatchability and embryo mortality and development but did increase ( < 0.05) activities of heart manganese superoxide dismutase (MnSOD) and liver copper zinc superoxide dismutase and liver MnSOD mRNA and protein levels in embryos. High incubation temperature also decreased ( < 0.003) HSP70 protein level in the heart but had no effects ( > 0.07) in the liver of embryos. Maternal diet with Mn supplementation not only increased ( < 0.05) the hatchability and Mn content ( < 0.001) in the yolk and embryonic tissues and the activity of MnSOD in the heart ( < 0.004) as well as relative liver weight ( < 0.05) under normal incubation temperature but also decreased ( ≤ 0.05) embryo mortality and HSP90 mRNA level in the liver and heart of embryos. Furthermore, under high incubation temperature, maternal diet Mn supplementation increased ( < 0.002) MnSOD protein expression in the liver of embryos but had no effect ( > 0.43) under normal incubation temperature. These results indicated that high incubation temperature induced self-protective responses of chick embryos with a modification of antioxidant status and a depression of HSP70 protein level. Maternal dietary supplementation of Mn could improve the hatchability as well as antioxidant ability to protect against heat challenge in embryos during incubation.

Excess caffeine exposure impairs eye development during chick embryogenesis

PubMed Central

Ma, Zheng-lai; Wang, Guang; Cheng, Xin; Chuai, Manli; Kurihara, Hiroshi; Lee, Kenneth Ka Ho; Yang, Xuesong

2014-01-01

Caffeine has been an integral component of our diet and medicines for centuries. It is now known that over consumption of caffeine has detrimental effects on our health, and also disrupts normal foetal development in pregnant mothers. In this study, we investigated the potential teratogenic effect of caffeine over-exposure on eye development in the early chick embryo. Firstly, we demonstrated that caffeine exposure caused chick embryos to develop asymmetrical microphthalmia and induced the orbital bone to develop abnormally. Secondly, caffeine exposure perturbed Pax6 expression in the retina of the developing eye. In addition, it perturbed the migration of HNK-1+ cranial neural crest cells. Pax6 is an important gene that regulates eye development, so altering the expression of this gene might be the cause for the abnormal eye development. Thirdly, we found that reactive oxygen species (ROS) production was significantly increased in eye tissues following caffeine treatment, and that the addition of anti-oxidant vitamin C could rescue the eyes from developing abnormally in the presence of caffeine. This suggests that excess ROS induced by caffeine is one of the mechanisms involved in the teratogenic alterations observed in the eye during embryogenesis. In sum, our experiments in the chick embryo demonstrated that caffeine is a potential teratogen. It causes asymmetrical microphthalmia to develop by increasing ROS production and perturbs Pax6 expression. PMID:24636305

Expression of neuronal antigens and related ventral and dorsal proteins in the normal spinal cord and a surgically induced open neural tube defect of the spine in chick embryos: an immunohistochemical study.

PubMed

Lee, Do-Hun; Phi, Ji Hoon; Chung, You-Nam; Lee, Yun-Jin; Kim, Seung-Ki; Cho, Byung-Kyu; Kim, Dong Won; Park, Moon-Sik; Wang, Kyu-Chang

2010-05-01

The aims of this study were to elucidate the processes of neuronal differentiation and ventrodorsal patterning in the spinal cord of the chick embryo from embryonic day (E) 3 to E17 and to study the effect of a prenatal spinal open neural tube defect (ONTD) on these processes. Expression patterns of neuronal antigens (neuronal nuclear antigen, neurofilament-associated protein (NAP), and synaptophysin) and related ventral markers [sonic hedgehog, paired box gene (PAX)6, and islet-1], and dorsal markers (bone morphogenetic protein, Notch homolog 1, and PAX7) were investigated in the normal spinal cord and in a surgically induced spinal ONTD in chick embryos. Four normal and ONTD chick embryos were used for each antigen group. There were no differences in the expression of neuronal and ventrodorsal markers between the control and ONTD groups. NAP and synaptophysin were useful for identifying dorsal structures in the distorted anatomy of the ONTD chicks.

Lectin histochemistry of goblet cell sugar residues in the gut of the chick embryo and of the newborn.

PubMed

Bryk, S G; Sgambati, E; Gheri Bryk, G

1999-04-01

The anlage of duodenum, ileum and colon were removed from chick embryos of day 8-21 of incubation and from 1-day-old chicks. A battery of seven different horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, Con A, WGA, LTA and UEAI) was used to study the carbohydrate residues of the glycoconjugates in the goblet cells of the three parts of the intestine. The main results can be summarized as follows: differences in lectin binding were absent in the proximal and distal parts of the duodenum, ileum and colon. Lectin histochemistry showed differences among the three intestinal segments for the time of appearance of the oligosaccharides in the goblet mucus. In the colonic goblet cells of 1-day-old chicks, LTA and UEAI lectins showed two different types of linkage of alpha-L-fucose. This is the first demonstration of UEAI reactive sites in Gallus domesticus.

The generation of vertebral segmental patterning in the chick embryo.

PubMed

Senthinathan, Biruntha; Sousa, Cátia; Tannahill, David; Keynes, Roger

2012-06-01

We have carried out a series of experimental manipulations in the chick embryo to assess whether the notochord, neural tube and spinal nerves influence segmental patterning of the vertebral column. Using Pax1 expression in the somite-derived sclerotomes as a marker for segmentation of the developing intervertebral disc, our results exclude such an influence. In contrast to certain teleost species, where the notochord has been shown to generate segmentation of the vertebral bodies (chordacentra), these experiments indicate that segmental patterning of the avian vertebral column arises autonomously in the somite mesoderm. We suggest that in amniotes, the subdivision of each sclerotome into non-miscible anterior and posterior halves plays a critical role in establishing vertebral segmentation, and in maintaining left/right alignment of the developing vertebral elements at the body midline. © 2012 The Authors. Journal of Anatomy © 2012 Anatomical Society.

THE SUSCEPTIBILITY OF CHICK EMBRYO SKIN ORGAN CULTURES TO INFLUENZA VIRUS FOLLOWING EXCESS VITAMIN A

PubMed Central

Huang, J. S.; Bang, F. B.

1964-01-01

The conversion of chick embryonic epidermis to mucous epithelium by excess vitamin A in organ culture as reported by Fell and Mellanby (5) was shown to be accompanied by a corresponding change of susceptibility to influenza and vaccinia viruses. Untreated epidermis of 10- to 12-day chick embryos supported the growth of influenza (PR8) virus in organ cultures and a maximum infectivity (EID50) titer was reached 2 to 3 days after infection. At the same time) the epidermis showed squamous keratinization, beginning about the 4th day of cultivation. Addition of excess vitamin A (40 µg per ml) to the skin organ culture induced the following changes: (a) mucous metaplasia of the epidermis which was usually first evident after 4 to 5 days in the vitamin A medium, (b) increase in the daily and maximum yield of influenza virus, if the epidermis had been grown for 4 or more days in the vitamin A medium before infection took place, and (c) decrease in the production of vaccinia virus under similar conditions. The maximum yield of both viruses remained unchanged, however, if excess vitamin A was introduced to the organ culture at the time of virus inoculation. The magnitude of increase in the yield of influenza virus in this organ culture system was found to be proportionally related to the concentration of vitamin A added 4 or more days before inoculation of this virus. Increasing doses of vitamin A however, had no effect on the short-term growth of influenza virus in tissue cultures of chorio-allantoic membrane. Observation on the early period (2 to 12 hours) of influenza virus growth initiated in the 4-day organ cultures of chick embryonic skin showed no significant difference in virus production between the normal and the vitamin A medium groups. The change of virus specificity apparently is not due to the presence of excess vitamin A per se, but appears to be related to the change of differentiation produced in the organ culture system. PMID:14206436

Chick ex ovo culture and ex ovo CAM assay: how it really works.

PubMed

Dohle, Daniel S; Pasa, Susanne D; Gustmann, Sebastian; Laub, Markus; Wissler, Josef H; Jennissen, Herbert P; Dünker, Nicole

2009-11-30

Chicken eggs in the early phase of breeding are between in vitro and in vivo systems and provide a vascular test environment not only to study angiogenesis but also to study tumorigenesis. After the chick chorioallantoic membrane (CAM) has developed, its blood vessel network can be easily accessed, manipulated and observed and therefore provides an optimal setting for angiogenesis assays. Since the lymphoid system is not fully developed until late stages of incubation, the chick embryo serves as a naturally immunodeficient host capable of sustaining grafted tissues and cells without species-specific restrictions. In addition to nurturing developing allo- and xenografts, the CAM blood vessel network provides a uniquely supportive environment for tumor cell intravasation, dissemination, and vascular arrest and a repository where arrested cells extravasate to form micro metastatic foci. For experimental purposes, in most of the recent studies the CAM was exposed by cutting a window through the egg shell and experiments were carried out in ovo, resulting in significant limitations in the accessibility of the CAM and possibilities for observation and photo documentation of effects. When shell-less cultures of the chick embryo were used(1-4), no experimental details were provided and, if published at all, the survival rates of these cultures were low. We refined the method of ex ovo culture of chick embryos significantly by introducing a rationally controlled extrusion of the egg content. These ex ovo cultures enhance the accessibility of the CAM and chick embryo, enabling easy in vivo documentation of effects and facilitating experimental manipulation of the embryo. This allows the successful application to a large number of scientific questions: (1) As an improved angiogenesis assay(5,6), (2) an experimental set up for facilitated injections in the vitreous of the chick embryo eye(7-9), (3) as a test environment for dissemination and intravasation of dispersed tumor

Chicken Embryos as a Potential New Model for Early Onset Type I Diabetes

PubMed Central

Shi, Liheng; Ko, Michael L.; Huang, Cathy Chia-Yu; Park, So-Young; Hong, Min-Pyo; Ko, Gladys Y.-P.

2014-01-01

Diabetic retinopathy (DR) is the leading cause of blindness among the American working population. The purpose of this study is to establish a new diabetic animal model using a cone-dominant avian species to address the distorted color vision and altered cone pathway responses in prediabetic and early diabetic patients. Chicken embryos were injected with either streptozotocin (STZ), high concentration of glucose (high-glucose), or vehicle at embryonic day 11. Cataracts occurred in varying degrees in both STZ- and high glucose-induced diabetic chick embryos at E18. Streptozotocin-diabetic chicken embryos had decreased levels of blood insulin, glucose transporter 4 (Glut4), and phosphorylated protein kinase B (pAKT). In STZ-injected E20 embryos, the ERG amplitudes of both a- and b-waves were significantly decreased, the implicit time of the a-wave was delayed, while that of the b-wave was significantly increased. Photoreceptors cultured from STZ-injected E18 embryos had a significant decrease in L-type voltage-gated calcium channel (L-VGCC) currents, which was reflected in the decreased level of L-VGCCα1D subunit in the STZ-diabetic retinas. Through these independent lines of evidence, STZ-injection was able to induce pathological conditions in the chicken embryonic retina, and it is promising to use chickens as a potential new animal model for type I diabetes. PMID:25133191

Mechanical Effects of the Surface Ectoderm on Optic Vesicle Morphogenesis in the Chick Embryo

PubMed Central

Hosseini, Hadi S.; Beebe, David C.; Taber, Larry A.

2014-01-01

Precise shaping of the eye is crucial for proper vision. Here, we use experiments on chick embryos along with computational models to examine the mechanical factors involved in the formation of the optic vesicles (OVs), which grow outward from the forebrain of the early embryo. First, mechanical dissections were used to remove the surface ectoderm (SE), a membrane that contacts the outer surfaces of the OVs. Principal components analysis of OV shapes suggests that the SE exerts asymmetric loads that cause the OVs to flatten and shear caudally during the earliest stages of eye development and later to bend in the caudal and dorsal directions. These deformations cause the initially spherical OVs to become pear-shaped. Exposure to the myosin II inhibitor blebbistatin reduced these effects, suggesting that cytoskeletal contraction controls OV shape by regulating tension in the SE. To test the physical plausibility of these interpretations, we developed 2-D finite-element models for frontal and transverse cross-sections of the forebrain, including frictionless contact between the SE and OVs. With geometric data used to specify differential growth in the OVs, these models were used to simulate each experiment (control, SE removed, no contraction). For each case, the predicted shape of the OV agrees reasonably well with experiments. The results of this study indicate that differential growth in the OV and external pressure exerted by the SE are suffcient to cause the global changes in OV shape observed during the earliest stages of eye development. PMID:25458577

AUTORADIOGRAPHIC STUDIES OF THE UTILIZATION OF S35-SULFATE BY THE CHICK EMBRYO

PubMed Central

Johnston, Perry M.; Comar, Cyril L.

1957-01-01

From studies of autoradiograms of various developmental stages of the chick embryo containing S35 given us sulfate it was determined that as early as Stages 3+ and 4 there is a selective utilization or accumulation of sulfate by the various parts. The earliest accumulation site is the axial portion of the primitive streak and the floor of the groove. Later S35 was found in the head process, Hensen's node, notochord, amniocardiac vesicle, wall of the omphalomesenteric vein, endocardium, subendocardial jelly, mesenchyme destined to become cartilage, basement membrane area of the gut, and a mucopolysaccharide layer formed on the free surface of the stomach. The early notochordal localizations of S35 coincide with the region in which a thin ring of chondroitin sulfate is subsequently laid down. However, it is apparent that there is an intracellular accumulation of inorganic sulfate by the chondroitin-forming cells prior to the time they produce sufficient chondroitin sulfate to be demonstrable histochemically. It was interesting to note that the endocardium appears to concentrate sulfate that later apparently finds its way into the subendocardial jelly. The fact that those mesenchymal cells which later form chondroblasts begin to utilize sulfate selectively before histological differentiation is apparent was determined. In addition, the presence of sulfate-containing substances in the forming basement membrane of the gut would seem to indicate that sulfate is important in the histological differentiation of this membrane. PMID:13438906

Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs.

PubMed

Kue, Chin Siang; Tan, Kae Yi; Lam, May Lynn; Lee, Hong Boon

2015-01-01

The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD(50)) in the CAM were measured and calculated for these drugs. The resultant ideal LD(50) values were correlated to those reported in the literature using Pearson's correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r(2)=0.42 - 0.68, P<0.005-0.05) between the ideal LD(50) values obtained using the CAM model with LD(50) values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs.

Chick embryo chorioallantoic membrane (CAM): an alternative predictive model in acute toxicological studies for anti-cancer drugs

PubMed Central

KUE, Chin Siang; TAN, Kae Yi; LAM, May Lynn; LEE, Hong Boon

2015-01-01

The chick embryo chorioallantoic membrane (CAM) is a preclinical model widely used for vascular and anti-vascular effects of therapeutic agents in vivo. In this study, we examine the suitability of CAM as a predictive model for acute toxicology studies of drugs by comparing it to conventional mouse and rat models for 10 FDA-approved anticancer drugs (paclitaxel, carmustine, camptothecin, cyclophosphamide, vincristine, cisplatin, aloin, mitomycin C, actinomycin-D, melphalan). Suitable formulations for intravenous administration were determined before the average of median lethal dose (LD50) and median survival dose (SD50) in the CAM were measured and calculated for these drugs. The resultant ideal LD50 values were correlated to those reported in the literature using Pearson’s correlation test for both intravenous and intraperitoneal routes of injection in rodents. Our results showed moderate correlations (r2=0.42 − 0.68, P<0.005–0.05) between the ideal LD50 values obtained using the CAM model with LD50 values from mice and rats models for both intravenous and intraperitoneal administrations, suggesting that the chick embryo may be a suitable alternative model for acute drug toxicity screening before embarking on full toxicological investigations in rodents in development of anticancer drugs. PMID:25736707

The expression dynamics of mechanosensitive genes in extra-embryonic vasculature after heart starts to beat in chick embryo.

PubMed

Rajendran, Saranya; Sundaresan, Lakshmikirupa; Rajendran, Krithika; Selvaraj, Monica; Gupta, Ravi; Chatterjee, Suvro

2016-02-11

Fluid flow plays an important role in vascular development. However, the detailed mechanisms, particularly the link between flow and modulation of gene expression during vascular development, remain unexplored. In chick embryo, the key events of vascular development from initiation of heart beat to establishment of effective blood flow occur between the stages HH10 and HH13. Therefore, we propose a novel in vivo model to study the flow experienced by developing endothelium. Using this model, we aimed to capture the transcriptome dynamics of the pre- and post-flow conditions. RNA was isolated from extra embryonic area vasculosa (EE-AV) pooled from three chick embryos between HH10-HH13 and RNA sequencing was performed. The whole transcriptome sequencing of chick identified up-regulation of some of the previously well-known mechanosensitive genes including NFR2, HAND1, CTGF and KDR. GO analyses of the up-regulated genes revealed enrichment of several biological processes including heart development, extracellular matrix organization, cell-matrix adhesion, cell migration, blood vessel development, patterning of blood vessels, collagen fibril organization. Genes encoding for gap junctions proteins which are involved in vascular remodeling and arterial-venous differentiation, and genes involved in cell-cell adhesion, and ECM interactions were significantly up-regulated. Validation of selected genes through semi quantitative PCR was performed. The study indicates that shear stress plays a major role in development. Through appropriate validation, this platform can serve as an in vivo model to study conditions of disturbed flow in pathology as well as normal flow during development.

Chick stem cells: Current progress and future prospects

PubMed Central

Intarapat, Sittipon; Stern, Claudio D.

2013-01-01

Chick embryonic stem cells (cESCs) can be derived from cells obtained from stage X embryos (blastoderm stage); these have the ability to contribute to all somatic lineages in chimaeras, but not to the germ line. However, lines of stem cells that are able to contribute to the germ line can be established from chick primordial germ cells (cPGCs) and embryonic germ cells (cEGCs). This review provides information on avian stem cells, emphasizing different sources of cells and current methods for derivation and culture of pluripotent cells from chick embryos. We also review technologies for isolation and derivation of chicken germ cells and the production of transgenic birds. PMID:24103496

Evidence against a direct role for oxidative stress in cadmium-induced axial malformation in the chick embryo

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

Thompson, Jennifer, E-mail: jennifer.thompson@ucd.i; Doi, Takashi; The Children's Research Centre, Our Lady's Children's Hospital, Dublin 12

Cadmium (Cd) is a powerful inducer of oxidative stress. It also causes ventral body wall defects in chick embryos treated at Hamburger-Hamilton stages 16-17. By measuring malondialdehyde levels (TBARS method) and cotreating with antioxidants (tempol, ascorbate, and N-acetylcysteine), we sought to determine if oxidative stress were directly related to teratogenesis. We also investigated the expression of mRNAs for antioxidant enzymes superoxide dismutase (SOD) -1 and -2, catalase (CAT), and glutathione peroxidase (GPx). RT-PCR showed reductions in SOD-1, SOD-2, and CAT 1 hour after treatment with Cd. MDA levels increased 4 hours after Cd, and remained elevated 24 hours after treatment.more » Of the antioxidants, only N-acetylcysteine reduced MDA levels to control values. Nonetheless, no antioxidant could reduce embryo lethality or malformation rates. Furthermore, MDA levels 24 hours after treatment were identical in malformed and normal embryos exposed to Cd. Hence, we conclude that oxidative stress may not have a direct role in Cd teratogenesis.« less

The effect of temporary reductions in incubation temperature on growth characteristics and lipid utilisation in the chick embryo

PubMed Central

FEAST, M.; NOBLE, R. C.; SPEAKE, B. K.; FERGUSON, M. W. J.

1998-01-01

The effect(s) of finite exposure(s) to 22.0 °C on embryo weight gain, 3rd tarsus length, transfer of lipid from the yolk and uptake of specific lipid components by the liver, were measured in the chick embryo. Embryo growth was completely suspended over the period of temperature reduction, but resumed unimpaired when the optimum temperature of 37.5 °C was restored. Two successive periods of embryonic exposure to 22.0 °C (36 h at d 3 followed by 24 at d 10) were additive in their effect on growth retardation. Embryos subjected to temperature reductions on d 3 of incubation displayed significant changes in lipid concentrations and polyunsaturated fatty acid profiles within the liver when measured at d 18 of incubation. Yolk lipid uptake was significantly reduced but not suspended by embryonic exposure to 22.0 °C. It is suggested that the observed suspension of embryonic development was the result of a temperature dependent reduction in metabolism according to a Q10∼2, which is typical of an ectothermic organism. PMID:9877293

Effect of a 1800 MHz electromagnetic field emitted during embryogenesis on chick development and hatchability.

PubMed

Pawlak, K; Nieckarz, Z; Sechman, A; Wojtysiak, D; Bojarski, B; Tombarkiewicz, B

2018-06-01

The level of artificial electromagnetic field (EMF) has steadily increased with the development of human civilization. The developing chicken embryo has been considered a good model to study the effects of EMF on living organisms. The aim of the study was to determine the effect of a 1800 MHz electromagnetic field during embryogenesis on the frequency of chick embryo malformations, morphometric parameters of the heart and liver and concentration of corticosterone in blood plasma, lipid and glycogen content in the liver of newly hatched chicks. A 1800 MHz EMF was found to shorten the duration of embryogenesis (earlier pipping and hatching of chicks) while having no effect on the quantity and quality of chicks and on increasing the incidence of embryo malformations. Exposure of chick embryos to EMF caused decreases in relative heart weight and right ventricle wall thickness. The pipping and hatching of chicks can be accelerated by stressful impact of EMF, which is confirmed by a significant increase in plasma corticosterone concentrations and decrease in fat and glycogen in the liver of chicks exposed during embryogenesis on the electromagnetic field with a frequency of 1800 MHz. © 2018 Blackwell Verlag GmbH.

Glycoconjugate sugar residues in the chick embryo developing lung: a lectin histochemical study.

PubMed

Gheri, G; Sgambati, E; Bryk, S G

2000-03-01

A lectin histochemical study was performed to investigate the distribution and changes of the oligosaccharidic component of the glycoconjugates in the lung of chick embryos, of 1-day-old chick, and of the adult animal. For this purpose, a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, Con A, LTA, and UEA I) were employed. During the first phase of parabronchi and atria formation, D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine, alpha-D-mannose, and sialic acid, present at the level of the surface and of cytoplasmic granules of the lining epithelial cells, seem to play a role in regulating morphogenetic phenomena. In the subsequent phases, the parabronchial lumen and the atrial cavities were characterized by the presence of lectin-reactive material rich in terminal D-galactose-(beta1-->3)-N-acetyl-D-galactosamine, beta-N-acetyl-D-galactosamine, D-glucosamine and alpha-D-mannose. From day 18 onwards and immediately after hatching, the free border of the cells lining the air capillaries was characterized by the presence of beta-N-acetyl-D-galactosamine and alpha-D-mannose. The appearance of these sugar residues was concomitant with the beginning of respiratory activity. Copyright 2000 Wiley-Liss, Inc.

Teratogenic effects of the neonicotinoid thiacloprid on chick embryos (Gallus gallus domesticus).

PubMed

Salvaggio, Antonio; Antoci, Francesco; Messina, Antonino; Ferrante, Margherita; Copat, Chiara; Ruberto, Claudia; Scalisi, Elena Maria; Pecoraro, Roberta; Brundo, Maria Violetta

2018-06-19

Thiacloprid is an insecticide belonging to the family of neonicotinoids, substances initially underestimated for their potential adverse effects, that they may manifest in the long term leading to an extensive use. The objective of this study was to evaluate the effect at increasing concentrations of thiacloprid on chick embryos development. The research was carried out on 75 fertile eggs of Gallus gallus domesticus. The eggs were opened after 10, 15 and 20 days of incubation and in treated embryos were observed developmental alterations, growth retardation, limbs defects and ectopia viscerale. The histological analysis showed hepatic steatosis and haemorrhages both in the liver and in the lungs. Moreover, the immunohistochemical analysis performed on the liver sections showed a strong positivity only for the erythrocytes to the anti-CYP1A antibody. Thiacloprid exposure increases the risks of teratogenic effects especially at the higher doses tested, therefore its use should be more controlled and limited. Since the literature on the topic is lacking, then the human health impacts resulting from neonicotinoids exposure is not yet fully understood, and, our data will be helpful to allow the assessment of an oral reference dose and health risk characterization. Copyright © 2018. Published by Elsevier Ltd.

The use of the chick embryo chorioallantoic membrane as experimental model to study virus growth and to test the clonal selection hypothesis. The contribution of Sir Mac Farlane Burnet.

PubMed

Ribatti, Domenico

2018-06-07

Sir Mac Farlane Burnet was the most honored of all Australian scientists. In 1960, Burnet shared the Nobel Prize for Medicine with Peter Medawar of Britain for the discovery of acquired immunological tolerance. He developed techniques for growing influenza viruses in the chorioallantoic membrane of the chick embryo. This became a standard laboratory practice. He continued to work with chick embryos long after the use of cell cultures had become general. His virology research resulted in significant discoveries concerning the nature and replication of viruses and their interaction with the immune system. Copyright © 2018 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Toxicity of scorpion venom in chick embryo and mealworm assay depending on the use of the soluble fraction versus the whole venom.

PubMed

van der Valk, Tom; van der Meijden, Arie

2014-09-01

The LD50 is an important metric for venom studies and antivenom development. It has been shown that several variables in the protocol influence the LD50 value obtained, such as venom source, extraction and treatment and administration route. These inconsistencies reduce the utility of the results of these test for comparative studies. In scorpion venom LD50 assays, often only the soluble fraction of the venom is used, whereas other studies use the whole venom. We here tested the toxicity of the soluble fraction in isolation, and of the whole venom in two different systems: chick embryos and mealworms Tenebrio molitor. Ten microliters of venom solutions from Hadrurus arizonensis, Leiurus quinquestriatus, Androctonus australis, Grosphus grandidieri and Heterometrus laoticus were applied to five day old chicken embryos at stage 25-27. Our results showed no significant differences between the LD50 based on the whole venom versus that of only the soluble fraction and in the chicken embryo assay in four of the five scorpion species tested. H. laoticus however, showed a significantly lower LD50 value for the whole venom than the soluble fraction. In assays on mealworms however, this pattern was not seen. Nonetheless, caution may be warranted when using LD50 values obtained from only the soluble fraction. The LD50 values of the five species in this study, based on the chicken embryo assay, showed good correlation with values from the literature based on mouse studies. This suggests that the chick embryo assay may be an economic alternative to rodent assays for scorpion LD50 studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

A descriptive study to provide evidence of the teratogenic and cellular effects of sibutramine and ephedrine on cardiac- and liver-tissue of chick embryos.

PubMed

Oberholzer, Hester Magdalena; Van Der Schoor, Ciska; Taute, Helena; Bester, Megan Jean

2015-08-01

Exposure to drugs during pregnancy is a major concern, as some teratogenic compounds can influence normal foetal development. Although the use of drugs during pregnancy should generally be avoided, exposure of the developing foetus to teratogens may occur unknowingly since these compounds may be hidden in products that are being marketed as "all natural." The aim of the current study was to investigate the possible teratogenic and cellular effects of sibutramine-a serotonin-norepinephrine reuptake inhibitor used in the treatment of obesity-on the heart and liver tissue of chick embryos. Ephedrine was used as a positive control. The chick embryo model was chosen because it has been used in studying developmental and experimental biology and teratology with great success. The embryos were exposed to three different concentrations of sibutramine and ephedrine respectively. The results obtained revealed that both compounds exhibited embryotoxicity when compared to the control groups. Liver and heart tissue of the exposed embryos was severely affected by these compounds in a dose-related manner. Morphology similar to that of muscle dystrophy was observed in the heart, where the muscle tissue was infiltrated by adipose and connective tissue. Severe liver steatosis was also noted. A more in-depth investigation into the molecular pathways involved might provide more information on the exact mechanism of toxicity of these products influencing embryonic development. © 2015 Wiley Periodicals, Inc.

Lectin histochemistry of enterocytes sugar residues in the gut of the chick embryo and of the newborn.

PubMed

Bryk, S Gheri; Gheri, G

2002-01-01

The glycoconjugates sugar residues content, distribution and changes in the enterocytes of different tracts of the developing intestine of the chick embryo and of 1-day-old chick were investigated, using a battery of seven HRP-conjugated lectins (DBA, SBA, PNA, WGA, ConA, LTA and UEAI). The results of the present research have shown the presence of a large amount of glycoconjugates sugar residues in the enterocytes of duodenal, ileal and colonic anlage, starting from the beginning of the second week of incubation. Differences were detected among the three investigated intestinal segments, as to the time of appearance of the glycoconjugates sugar residues in the enterocytes. The duodenal enterocytes showed the most precocious appearance of lectin-reactive material, followed by the ileal enterocytes and afterwards by colonic enterocytes. The duodenal enterocytes were characterised by the presence of SBA binding sites, which were not detectable in the duodenal enterocytes of the adult animal.

The Chick Embryo Chorioallantoic Membrane as an In Vivo Assay to Study Antiangiogenesis

PubMed Central

Ribatti, Domenico

2010-01-01

Antiangiogenesis, e.g., inhibition of blood vessel growth, is being investigated as a way to prevent the growth of tumors and other angiogenesis-dependent diseases. Pharmacological inhibition interferes with the angiogenic cascade or the immature neovasculature with synthetic or semi-synthetic substances, endogenous inhibitors or biological antagonists. The chick embryo chorioallantoic membrane (CAM) is an extraembryonic membrane, which serves as a gas exchange surface and its function is supported by a dense capillary network. Because its extensive vascularization and easy accessibility, CAM has been used to study morphofunctional aspects of the angiogenesis process in vivo and to study the efficacy and mechanism of action of pro- and anti-angiogenic molecules. The fields of application of CAM in the study of antiangiogenesis, including our personal experience, are illustrated in this review article. PMID:27713265

HNK-1 immunoreactivity during early morphogenesis of the head region in a nonmodel vertebrate, crocodile embryo

NASA Astrophysics Data System (ADS)

Kundrát, Martin

2008-11-01

The present study examines HNK-1 immunoidentification of a population of the neural crest (NC) during early head morphogenesis in the nonmodel vertebrate, the crocodile ( Crocodylus niloticus) embryos. Although HNK-1 is not an exclusive NC marker among vertebrates, temporospatial immunoreactive patterns found in the crocodile are almost consistent with NC patterns derived from gene expression studies known in birds (the closest living relatives of crocodiles) and mammals. In contrast to birds, the HNK-1 epitope is immunoreactive in NC cells at the neural fold level in crocodile embryos and therefore provides sufficient base to assess early migratory events of the cephalic NC. I found that crocodile NC forms three classic migratory pathways in the head: mandibular, hyoid, and branchial. Further, I demonstrate that, besides this classic phenotype, there is also a forebrain-derived migratory population, which consolidates into a premandibular stream in the crocodile. In contrast to the closely related chick model, crocodilian premandibular and mandibular NC cells arise from the open neural tube suggesting that species-specific heterochronic behavior of NC may be involved in the formation of different vertebrate facial phenotypes.

Neurotoxicological effects of nicotine on the embryonic development of cerebellar cortex of chick embryo during various stages of incubation.

PubMed

El-Beltagy, Abd El-Fattah B M; Abou-El-Naga, Amoura M; Sabry, Dalia M

2015-10-01

Long-acting nicotine is known to exert pathological effects on almost all tissues including the cerebellar cortex. The present work was designed to elucidate the effect of nicotine on the development of cerebellar cortex of chick embryo during incubation period. The fertilized eggs of hen (Gallus gallus domesticus) were injected into the air space by a single dose of long acting nicotine (1.6 mg/kg/egg) at the 4th day of incubation. The embryos were taken out of the eggs on days 8, 12 and 16 of incubation. The cerebellum of the control and treated embryos at above ages were processed for histopathological examination. The TEM were examined at 16th day of incubation. The results of the present study revealed that, exposure to long-acting nicotine markedly influence the histogenesis of cerebellar cortex of chick embryo during the incubation period. At 8th day of incubation, nicotine delayed the differentiation of the cerebellar analge; especially the external granular layer (EGL) and inner cortical layer (ICL). Furthermore, at 12th day of incubation, the cerebellar foliation was irregular and the Purkinje cells not recognized. By 16th day of incubation, the cerebellar foliations were irregular with interrupted cerebellar cortex and irregular arrangement of Purkinje cells. Immunohistochemical analysis for antibody P53 protein revealed that the cerebellar cortex in all stages of nicotine treated groups possessed a moderate to weak reaction for P53 protein however; this reaction was markedly stronger in the cerebellar cortex of control groups. Moreover, the flow cytometric analysis confirmed that the percentage of apoptosis in control group was significantly higher compared with that of nicotine treated group. At the TEM level, the cerebellar Purkinje cells of 16th day of treated groups showed multiple subcellular alterations in compared with those of the corresponding control group. Such changes represented by appearing of vacuolated mitochondria, cisternal

Effects of chromium picolinate on the viability of chick embryo fibroblast.

PubMed

Bai, Y; Zhao, X; Qi, C; Wang, L; Cheng, Z; Liu, M; Liu, J; Yang, D; Wang, S; Chai, T

2014-04-01

Chromium picolinate (CrPic), which is used as a nutritional supplement and to treat type 2 diabetes, has gained much attention because of its cytotoxicity. This study evaluated the effects of CrPic on the viability of the chick embryo fibroblast (CEF) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, morphological detection, and flow cytometry. The results show that lower concentrations of CrPic (8 and 16 μM) did not damage CEF viability (p > 0.05). However, higher CrPic concentrations (400 and 600 μM) indicated a highly significant effect on the production of intracellular reactive oxygen species, alteration of mitochondrial membrane potential, intracellular calcium ion concentration, and the apoptosis rate (p < 0.01), contrary to lower CrPic concentrations (8 and 16 μM) and control group. Moreover, apoptotic morphological changes induced by these processes in CEF were confirmed using Hoechst 33258 staining. Cell death induced by higher concentrations of CrPic was caused by an apoptotic and a necrotic mechanism, whereas the main mechanism of oxidative stress-induced mitochondrial dysfunction was apoptotic death.

Direct visualization of the Wntless-induced redistribution of WNT1 in developing chick embryos.

PubMed

Galli, Lisa M; Santana, Frederick; Apollon, Chantilly; Szabo, Linda A; Ngo, Keri; Burrus, Laura W

2018-04-30

Paracrine Wnt signals are critical regulators of cell proliferation, specification, and differentiation during embryogenesis. Consistent with the discovery that Wnt ligands are post-translationally modified with palmitoleate (a 16 carbon mono-unsaturated fatty acid), our studies show that the vast majority of bioavailable chick WNT1 (cWNT1) produced in stably transfected L cells is cell-associated. Thus, it seems unlikely that the WNT1 signal is propagated by diffusion alone. Unfortunately, the production and transport of vertebrate Wnt proteins has been exceedingly difficult to study as few antibodies are able to detect endogenous Wnt proteins and fixation is known to disrupt the architecture of cells and tissues. Furthermore, vertebrate Wnts have been extraordinarily refractory to tagging. To help overcome these obstacles, we have generated a number of tools that permit the detection of WNT1 in palmitoylation assays and the visualization of chick and zebrafish WNT1 in live cells and tissues. Consistent with previous studies in fixed cells, live imaging of cells and tissues with overexpressed cWNT1-moxGFP shows predominant localization of the protein to a reticulated network that is likely to be the endoplasmic reticulum. As PORCN and WLS are important upstream regulators of Wnt gradient formation, we also undertook the generation of mCherry-tagged variants of both proteins. While co-expression of PORCN-mCherry had no discernible effect on the localization of WNT1-moxGFP, co-expression of WLS-mCherry caused a marked redistribution of WNT1-moxGFP to the cell surface and cellular projections in cultured cells as well as in neural crest and surface ectoderm cells in developing chick embryos. Our studies further establish that the levels of WLS, and not PORCN, are rate limiting with respect to WNT1 trafficking. Copyright © 2018. Published by Elsevier Inc.

Sensory regulation of spontaneous limb movements in the midstage embryonic chick.

PubMed

Sharp, Andrew A

2015-05-01

It is becoming increasingly apparent that somatosensation plays an important role in regulating prenatal movement and developmental plasticity. Numerous studies performed on embryonic chicks and perinatal rats are beginning to implicate proprioception to be particularly important in modulating motility very soon after afferent connections are made in the spinal cord. In this report, we demonstrate new approaches in the chick embryo to explore the role of sensation in modulating embryonic movement. Force recordings from the legs of chick embryos on E9 and E11, during spontaneous motility, demonstrate changes in sensory regulation consistent with the concept that sensory regulation is functioning one day after sensory synapse formation and that the complexity of this regulation increases by E11. Additionally, we present new video data showing activation of embryonic motility on E5 and E9 in embryos expressing channelrhodopsin in the spinal cord as a novel way to approach the issues of sensorimotor development. © 2015 Wiley Periodicals, Inc.

Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

PubMed

Bertin, Aline; Meurisse, Maryse; Arnould, Cécile; Leterrier, Christine; Constantin, Paul; Cornilleau, Fabien; Vaudin, Pascal; Burlot, Thierry; Delaveau, Joel; Rat, Christophe; Calandreau, Ludovic

2016-03-01

In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors. © 2015 Wiley Periodicals, Inc.

HoxB2, HoxB4 and Alx4 genes are downregulated in the cadmium-induced omphalocele in the chick model.

PubMed

Doi, Takashi; Puri, Prem; Bannigan, John; Thompson, Jennifer

2010-10-01

In the chick embryo, administration of cadmium (Cd) induces omphalocele phenotype. HoxB2 and HoxB4, expressed in cell types that contribute to ventral body wall (VBW) formation, act together to mediate proper closure of the VBW, involving a key downstream transcription factor, Alx4. HoxB2 and HoxB4 knockout mice display VBW defects with specific downregulation of Alx4 gene expression, while homozygous Alx4 knockouts show omphalocele phenotype. Although the earliest histological changes in the Cd chick model occur commencing at 4H post treatment, the exact timing and molecular mechanism by which Cd acts is still unclear. We hypothesized that HoxB2, HoxB4 and Alx4 genes are downregulated during the critical timing of very early embryogenesis in the Cd-induced omphalocele chick model. After 60H incubation, chick embryos were harvested at 1H, 4H and 8H after treatment with saline or Cd and divided into controls and Cd group (n = 24 for each group). RT-PCR was performed to investigate the gene expression of HoxB2, HoxB4 and Alx4 and statistically analyzed (significance was accepted at p < 0.05). Immunohistochemical staining was also performed to evaluate the protein expression/distribution of HoxB2, HoxB4 and Alx4 in the chick embryo. The expression levels of HoxB2, HoxB4 and Alx4 gene at 4H were significantly downregulated in the Cd group as compared to controls, whereas there were no significant differences at the other time points. Immunoreactivity of HoxB2, HoxB4 and Alx4 at 4H is also markedly decreased in the ectoderm and the dermomyotome in the Cd chick model as compared to controls. Downregulation of HoxB2, HoxB4 and Alx4 expression during the narrow window of early embryogenesis may cause omphalocele in the Cd chick model by interfering with molecular signaling required for proper VBW formation. Furthermore, these results support the concept that HoxB2, HoxB4 and Alx4 genes work together to mediate proper VBW formation.

NMR Based Cerebrum Metabonomic Analysis Reveals Simultaneous Interconnected Changes during Chick Embryo Incubation.

PubMed

Feng, Yue; Zhu, Hang; Zhang, Xu; Wang, Xuxia; Xu, Fuqiang; Tang, Huiru; Ye, Chaohui; Liu, Maili

2015-01-01

To find out if content changes of the major functional cerebrum metabolites are interconnected and formed a network during the brain development, we obtained high-resolution magic-angle-spinning (HR-MAS) 1H NMR spectra of cerebrum tissues of chick embryo aged from incubation day 10 to 20, and postnatal day 1, and analyzed the data with principal component analysis (PCA). Within the examined time window, 26 biological important molecules were identified and 12 of them changed their relative concentration significantly in a time-dependent manner. These metabolites are generally belonged to three categories, neurotransmitters, nutrition sources, and neuronal or glial markers. The relative concentration changes of the metabolites were interconnected among/between the categories, and, more interestingly, associated with the number and size of Nissl-positive neurons. These results provided valuable biochemical and neurochemical information to understand the development of the embryonic brain.

NMR Based Cerebrum Metabonomic Analysis Reveals Simultaneous Interconnected Changes during Chick Embryo Incubation

PubMed Central

Feng, Yue; Zhu, Hang; Zhang, Xu; Wang, Xuxia; Xu, Fuqiang; Tang, Huiru; Ye, Chaohui; Liu, Maili

2015-01-01

To find out if content changes of the major functional cerebrum metabolites are interconnected and formed a network during the brain development, we obtained high-resolution magic-angle-spinning (HR-MAS) 1H NMR spectra of cerebrum tissues of chick embryo aged from incubation day 10 to 20, and postnatal day 1, and analyzed the data with principal component analysis (PCA). Within the examined time window, 26 biological important molecules were identified and 12 of them changed their relative concentration significantly in a time-dependent manner. These metabolites are generally belonged to three categories, neurotransmitters, nutrition sources, and neuronal or glial markers. The relative concentration changes of the metabolites were interconnected among/between the categories, and, more interestingly, associated with the number and size of Nissl-positive neurons. These results provided valuable biochemical and neurochemical information to understand the development of the embryonic brain. PMID:26485040

Retinoic acid, hemin and hexamethylen bisacetamide interference with "in vitro" differentiation of chick embryo chondrocytes.

PubMed

Manduca, P; Abelmoschi, M L

1992-01-01

We have investigated the effect of all-trans Retinoic acid, and of substances (Hemine and Hexamethylene bisacetamide) which interfere with "in vitro" differentiation of mesenchyme derived cell lineages on the expression of specific markers of hyperthrophy in "in vitro" differentiating chick embryo chondrocytes. (Castagnola P., et al., 1986). Continuous treatment of chondrogenic cells in conditions allowing differentiation "in vitro" with Retinoic acid resulted in persistence of type I collagen synthesis and in lack of type X collagen and Ch 21 protein expression. Hemin treated cells secreted a reduced amount of type X collagen. HMBA treatment inhibited type X collagen expression and caused reduction of the ratio between type II collagen and Ch 21 synthesized. The data indicate an independent regulation of these markers during chondrocyte differentiation.

The effects of an environmentally relevant 58-congener polychlorinated biphenyl (PCB) mixture on cardiac development in the chick embryo.

PubMed

Carro, Tiffany; Taneyhill, Lisa A; Ann Ottinger, Mary

2013-06-01

Chicken (Gallus domesticus) embryonic exposure in ovo to a 58-congener polychlorinated biphenyl (PCB) mixture resulted in teratogenic heart defects in chick embryos at critical heart developmental stages Hamburger-Hamilton (HH) stages 10, 16, and 20. The 58-congener mixture contained relative proportions of primary congeners measured in belted sandpiper (Megaceryle alcyon) and spotted sandpiper (Actitis macularia) eggs collected along the upper Hudson River, New York, USA, and chicken doses were well below observed environmental exposure levels. Embryos were injected with 0.08 µg PCBs/g egg weight and 0.50 µg PCBs/g egg weight (0.01 and 0.064 ng toxic equivalent/g, respectively) at embryonic day 0, prior to incubation. Mortality of exposed embryos was increased at all developmental stages, with a marked rise in cardiomyopathies at HH16 and HH20 (p < 0.05). Heart abnormalities occurred across all treatments, including abnormal elongation and expansion of the heart tube at HH10, improper looping and orientation, indentations in the emerging ventricular wall (HH16 and HH20), and irregularities in overall heart shape (HH10, HH16, and HH20). Histology was conducted on 2 cardiac proteins critical to embryonic heart development, ventricular myosin heavy chain and titin, to investigate potential mechanistic effects of PCBs on heart development, but no difference was observed in spatiotemporal expression. Similarly, cellular apoptosis in the developing heart was not affected by exposure to the PCB mixture. Conversely, cardiomyocyte proliferation rates dramatically declined (p < 0.01) at HH16 and HH20 as PCB exposure concentrations increased. Early embryonic cardiomyocyte proliferation contributes to proper formation of the morphology and overall thickness of the ventricular wall. Therefore, in ovo exposure to this 58-congener PCB mixture at critical stages adversely affects embryonic heart development. Copyright © 2013 SETAC.

3D Reconstruction of Chick Embryo Vascular Geometries Using Non-invasive High-Frequency Ultrasound for Computational Fluid Dynamics Studies.

PubMed

Tan, Germaine Xin Yi; Jamil, Muhammad; Tee, Nicole Gui Zhen; Zhong, Liang; Yap, Choon Hwai

2015-11-01

Recent animal studies have provided evidence that prenatal blood flow fluid mechanics may play a role in the pathogenesis of congenital cardiovascular malformations. To further these researches, it is important to have an imaging technique for small animal embryos with sufficient resolution to support computational fluid dynamics studies, and that is also non-invasive and non-destructive to allow for subject-specific, longitudinal studies. In the current study, we developed such a technique, based on ultrasound biomicroscopy scans on chick embryos. Our technique included a motion cancelation algorithm to negate embryonic body motion, a temporal averaging algorithm to differentiate blood spaces from tissue spaces, and 3D reconstruction of blood volumes in the embryo. The accuracy of the reconstructed models was validated with direct stereoscopic measurements. A computational fluid dynamics simulation was performed to model fluid flow in the generated construct of a Hamburger-Hamilton (HH) stage 27 embryo. Simulation results showed that there were divergent streamlines and a low shear region at the carotid duct, which may be linked to the carotid duct's eventual regression and disappearance by HH stage 34. We show that our technique has sufficient resolution to produce accurate geometries for computational fluid dynamics simulations to quantify embryonic cardiovascular fluid mechanics.

Motor neurons with limb-innervating character in the cervical spinal cord are sculpted by apoptosis based on the Hox code in chick embryo.

PubMed

Mukaigasa, Katsuki; Sakuma, Chie; Okada, Tomoaki; Homma, Shunsaku; Shimada, Takako; Nishiyama, Keiji; Sato, Noboru; Yaginuma, Hiroyuki

2017-12-15

In the developing chick embryo, a certain population of motor neurons (MNs) in the non-limb-innervating cervical spinal cord undergoes apoptosis between embryonic days 4 and 5. However, the characteristics of these apoptotic MNs remain undefined. Here, by examining the spatiotemporal profiles of apoptosis and MN subtype marker expression in normal or apoptosis-inhibited chick embryos, we found that this apoptotic population is distinguishable by Foxp1 expression. When apoptosis was inhibited, the Foxp1 + MNs survived and showed characteristics of lateral motor column (LMC) neurons, which are of a limb-innervating subtype, suggesting that cervical Foxp1 + MNs are the rostral continuation of the LMC. Knockdown and misexpression of Foxp1 did not affect apoptosis progression, but revealed the role of Foxp1 in conferring LMC identity on the cervical MNs. Furthermore, ectopic expression of Hox genes that are normally expressed in the brachial region prevented apoptosis, and directed Foxp1 + MNs to LMC neurons at the cervical level. These results indicate that apoptosis in the cervical spinal cord plays a role in sculpting Foxp1 + MNs committed to LMC neurons, depending on the Hox expression pattern. © 2017. Published by The Company of Biologists Ltd.

Early development of the circumferential axonal pathway in mouse and chick spinal cord.

PubMed

Holley, J A

1982-03-10

The early development of the circumferential axonal pathway in the brachial and lumbar spinal cord of mouse and chick embryos was studied by scanning and transmission electron microscopy. The cellular processes which comprise this pathway grow in the transverse plane and along the lateral margin of the marginal zone (i.e., circumferentially oriented), as typified by the early embryonic commissural axons. The first formative event observed was in the ventrolateral margin of the primitive spinal cord ventricular zone. Cellular processes were found near the external limiting membrane that appeared to grow a variable distance either dorsally or ventrally. Later in development, presumptive motor column neurons migrated into the ventrolateral region, distal to these early circumferentially oriented processes. Concurrently, other circumferentially oriented perikarya and processes appeared along the dorsolateral margin. Due to their aligned sites of origin and parallel growth, the circumferential processes formed a more or less continuous line or pathway, which in about 10% of the scanned specimens could be followed along the entire lateral margin of the embryonic spinal cord. Several specimens later in development had two sets of aligned circumferential processes in the ventral region. Large numbers of circumferential axons were then found to follow the preformed pathway by fasciculation, after the primitive motor column had become established. Since the earliest circumferential processes appeared to differentiate into axons and were found nearly 24 hours prior to growth of most circumferential axons, their role in guidance as pioneering axons was suggested.

Early stages of memory formation in filial imprinting: Fos-like immunoreactivity and behavior in the domestic chick.

PubMed

Suge, R; McCabe, B J

2004-01-01

Early stages of memory formation in filial imprinting were studied in domestic chicks. Chicks trained for 15 min showed strong imprinting, demonstrated by a strong preference for their training stimulus, and the time course of this preference over 2 days after training was similar to that of chicks trained for 60 min. The chicks therefore learned characteristics of the training stimulus very early during training. The intermediate and medial hyperstriatum ventrale (IMHV) is a part of the chick forebrain that is crucial for imprinting. Previous experiments have shown a learning-specific increase in Fos-like immunoreactivity, used as a marker of neuronal activity, in the IMHV after training for 60 min. The time course of Fos expression in the IMHV was measured after training for 15 min and 60 min. The same pattern of expression was found for both training times, showing a peak 120 min after the start of training. The time course of expression was stimulus-dependent. Fos expression in the IMHV, but not the hippocampus, was significantly correlated with strength of imprinting. It is concluded that the learning-specific change in Fos expression in the IMHV is associated with very early components of memory formation.

Misexpression of BRE gene in the developing chick neural tube affects neurulation and somitogenesis

PubMed Central

Wang, Guang; Li, Yan; Wang, Xiao-Yu; Chuai, Manli; Yeuk-Hon Chan, John; Lei, Jian; Münsterberg, Andrea; Lee, Kenneth Ka Ho; Yang, Xuesong

2015-01-01

The brain and reproductive expression (BRE) gene is expressed in numerous adult tissues and especially in the nervous and reproductive systems. However, little is known about BRE expression in the developing embryo or about its role in embryonic development. In this study, we used in situ hybridization to reveal the spatiotemporal expression pattern for BRE in chick embryo during development. To determine the importance of BRE in neurogenesis, we overexpressed BRE and also silenced BRE expression specifically in the neural tube. We established that overexpressing BRE in the neural tube indirectly accelerated Pax7+ somite development and directly increased HNK-1+ neural crest cell (NCC) migration and TuJ-1+ neurite outgrowth. These altered morphogenetic processes were associated with changes in the cell cycle of NCCs and neural tube cells. The inverse effect was obtained when BRE expression was silenced in the neural tube. We also determined that BMP4 and Shh expression in the neural tube was affected by misexpression of BRE. This provides a possible mechanism for how altering BRE expression was able to affect somitogenesis, neurogenesis, and NCC migration. In summary, our results demonstrate that BRE plays an important role in regulating neurogenesis and indirectly somite differentiation during early chick embryo development. PMID:25568339

Glassfrog embryos hatch early after parental desertion.

PubMed

Delia, Jesse R J; Ramírez-Bautista, Aurelio; Summers, Kyle

2014-06-22

Both parental care and hatching plasticity can improve embryo survival. Research has found that parents can alter hatching time owing to a direct effect of care on embryogenesis or via forms of care that cue the hatching process. Because parental care alters conditions critical for offspring development, hatching plasticity could allow embryos to exploit variation in parental behaviour. However, this interaction of parental care and hatching plasticity remains largely unexplored. We tested the hypothesis that embryos hatch early to cope with paternal abandonment in the glassfrog Hyalinobatrachium fleischmanni (Centrolenidae). We conducted male-removal experiments in a wild population, and examined embryos' response to conditions with and without fathers. Embryos hatched early when abandoned, but extended development in the egg stage when fathers continued care. Paternal care had no effect on developmental rate. Rather, hatching plasticity was due to embryos actively hatching at different developmental stages, probably in response to deteriorating conditions without fathers. Our experimental results are supported by a significant correlation between the natural timing of abandonment and hatching in an unmanipulated population. This study demonstrates that embryos can respond to conditions resulting from parental abandonment, and provides insights into how variation in care can affect selection on egg-stage adaptations.

Glassfrog embryos hatch early after parental desertion

PubMed Central

Delia, Jesse R. J.; Ramírez-Bautista, Aurelio; Summers, Kyle

2014-01-01

Both parental care and hatching plasticity can improve embryo survival. Research has found that parents can alter hatching time owing to a direct effect of care on embryogenesis or via forms of care that cue the hatching process. Because parental care alters conditions critical for offspring development, hatching plasticity could allow embryos to exploit variation in parental behaviour. However, this interaction of parental care and hatching plasticity remains largely unexplored. We tested the hypothesis that embryos hatch early to cope with paternal abandonment in the glassfrog Hyalinobatrachium fleischmanni (Centrolenidae). We conducted male-removal experiments in a wild population, and examined embryos' response to conditions with and without fathers. Embryos hatched early when abandoned, but extended development in the egg stage when fathers continued care. Paternal care had no effect on developmental rate. Rather, hatching plasticity was due to embryos actively hatching at different developmental stages, probably in response to deteriorating conditions without fathers. Our experimental results are supported by a significant correlation between the natural timing of abandonment and hatching in an unmanipulated population. This study demonstrates that embryos can respond to conditions resulting from parental abandonment, and provides insights into how variation in care can affect selection on egg-stage adaptations. PMID:24789892

Neural differentiation of caudal cell mass (secondary neurulation) in chick embryos: Hamburger and Hamilton Stages 16-45.

PubMed

Yang, Hee-Jin; Wang, Kyu-Chang; Chi, Je G; Lee, Myung-Sook; Lee, Yun-Jin; Kim, Seung-Ki; Cho, Byung-Kyu

2003-04-14

In an attempt to understand the events in the secondary neurulation in embryonic stage, we investigated morphological changes in the tail bud of normal developing chick embryos. Hamburger and Hamilton stage 16-45 embryos were harvested and processed for light microscopic studies. The secondary neural tube is formed by aggregation of the caudal cell mass. Cells are arranged into a cord-like mass (medullary cord), which is continuous with the primary neural tube. Multiple small cavities develop in the medullary cord, and these cavities coalesce into one single lumen. The process of coalescence is completed by stage 35, and the whole neural tube is transformed into one tube with a single continuous lumen. At this stage, the terminal portion of the neural tube is bulged dorsally. Thereafter, the caudal portion of the neural tube regresses, and the proximal portion develops into normal spinal cord. Transient occlusion of the central canal was observed at stage 40 in one sample. The sequence of events elucidated in this study can be used as base-line data for experiments concerning congenital malformations involving secondary neurulation.

Characterization of cDNAs encoding the chick retinoic acid receptor gamma 2 and preferential distribution of retinoic acid receptor gamma transcripts during chick skin development.

PubMed

Michaille, J J; Blanchet, S; Kanzler, B; Garnier, J M; Dhouailly, D

1994-12-01

Retinoic acid receptors alpha, beta and gamma (RAR alpha, beta and gamma) are ligand-inductible transcriptional activators which belong to the steroid/thyroid hormone receptor superfamily. At least two major isoforms (1 and 2) of each RAR arise by differential use of two promoters and alternative splicing. In mouse, the three RAR genes are expressed in stage- and tissue-specific patterns during embryonic development. In order to understand the role of the different RARs in chick, RAR gamma 2 cDNAs were isolated from an 8.5-day (stage 35 of Hamburger and Hamilton) chick embryo skin library. The deduced chick RAR gamma 2 amino acid sequence displays uncommon features such as 21 specific amino acid replacements, 12 of them being clustered in the amino-terminal region (domains A2 and B), and a truncated acidic carboxy-terminal region (F domain). However, the pattern of RAR gamma expression in chick embryo resembles that reported in mouse, particularly in skin where RAR gamma expression occurs in both the dermal and epidermal layers at the beginning of feather formation, and is subsequently restricted to the differentiating epidermal cells. Northern blot analysis suggests that different RAR gamma isoforms could be successively required during chick development.

Layer chicken embryo survival to hatch when administered an in ovo vaccination of strain F Mycoplasma gallisepticum and locations of bacteria prevalence in the newly hatched chick.

PubMed

Elliott, K E C; Branton, S L; Evans, J D; Gerard, P D; Peebles, E D

2017-09-01

Mycoplasma gallisepticum (MG) is a bacterial pathogen that causes production losses in layer chickens. To combat MG, multiage layer facilities vaccinate pullets by either spray or eye-drop vaccination. The objective in this study was to evaluate the use of in ovo vaccination as a potential alternative for MG vaccination. Layer embryos at 18 d of incubation were either not-injected (control), or were hand-injected with either commercial Marek's disease vaccine diluent alone or with a high, medium, low, or very low dosage of a live attenuated strain F (FMG) vaccine suspended in the commercial diluent. Hatch success and residual egg embryonic mortality were determined after 23 d of incubation. Six hatched chicks per treatment were swabbed for the detection of FMG at 4 different sites (trachea, mouth and esophagus, yolk sac membrane, and the lumen of the duodenal loop) via real-time PCR. Embryos were found to be administered 106 CFU per dose in the high treatment, 104 CFU/dose in the medium treatment, 102 CFU/dose in the low treatment, and between 5.06 and 5.93 CFU/dose in the very low treatment. Hatch of embryonated eggs was decreased by the medium and high doses (P = 0.02). These embryos died while pipping. No FMG was detected in the control and diluent-injected chicks. In the FMG treatments, FMG was found in all sites and dosages, with a greater number of positive chicks found in the higher FMG dosage treatments. These findings indicate the potential practicality of vaccinating layer embryos with FMG by in ovo injection based on the observed hatch success at lower dosages. Also, once injected into the amnion, the bacteria are present in the upper respiratory and gastrointestinal tracts as well the yolk sac membrane and the small intestine of hatchlings. Future research will need to ascertain the effects of FMG administered by in ovo injection on posthatch immunity and mortality. © 2017 Poultry Science Association Inc.

Egg storage duration and hatch window affect gene expression of nutrient transporters and intestine morphological parameters of early hatched broiler chicks.

PubMed

Yalcin, S; Gursel, I; Bilgen, G; Izzetoglu, G T; Horuluoglu, B H; Gucluer, G

2016-05-01

In recent years, researchers have given emphasis on the differences in physiological parameters between early and late hatched chicks within a hatch window. Considering the importance of intestine development in newly hatched chicks, however, changes in gene expression of nutrient transporters in the jejunum of early hatched chicks within a hatch window have not been studied yet. This study was conducted to determine the effects of egg storage duration before incubation and hatch window on intestinal development and expression of PepT1 (H+-dependent peptide transporter) and SGLT1 (sodium-glucose co-transporter) genes in the jejunum of early hatched broiler chicks within a 30 h of hatch window. A total of 1218 eggs obtained from 38-week-old Ross 308 broiler breeder flocks were stored for 3 (ES3) or 14 days (ES14) and incubated at the same conditions. Eggs were checked between 475 and 480 h of incubation and 40 chicks from each egg storage duration were weighed; chick length and rectal temperature were measured. The chicks were sampled to evaluate morphological parameters and PepT1 and SGLT1 expression. The remaining chicks that hatched between 475 and 480 h were placed back in the incubator and the same measurements were conducted with those chicks at the end of hatch window at 510 h of incubation. Chick length, chick dry matter content, rectal temperature and weight of small intestine segments increased, whereas chick weight decreased during the hatch window. The increase in the jejunum length and villus width and area during the hatch window were higher for ES3 than ES14 chicks. PepT1 expression was higher for ES3 chicks compared with ES14. There was a 10.2 and 17.6-fold increase in PepT1 and SGLT1 expression of ES3 chicks at the end of hatch window, whereas it was only 2.3 and 3.3-fold, respectively, for ES14 chicks. These results suggested that egg storage duration affected development of early hatched chicks during 30 h of hatch window. It can be concluded that

Embryo sac formation and early embryo development in Agave tequilana (Asparagaceae).

PubMed

González-Gutiérrez, Alejandra G; Gutiérrez-Mora, Antonia; Rodríguez-Garay, Benjamín

2014-01-01

Agave tequilana is an angiosperm species that belongs to the family Asparagaceae (formerly Agavaceae). Even though there is information regarding to some aspects related to the megagametogenesis of A. tequilana, this is the first report describing the complete process of megasporogenesis, megagametogenesis, the early embryo and endosperm development process in detail. The objective of this work was to study and characterize all the above processes and the distinctive morphological changes of the micropylar and chalazal extremes after fertilization in this species. The agave plant material for the present study was collected from commercial plantations in the state of Jalisco, Mexico. Ovules and immature seeds, previously fixed in FAA and kept in ethanol 70%, were stained based on a tissue clarification technique by using a Mayer's-Hematoxylin solution. The tissue clarification technique was successfully used for the characterization of the megasporogenesis, megagametogenesis, mature embryo sac formation, the early embryo and endosperm development processes by studying intact cells. The embryo sac of A. tequilana was confirmed to be of the monosporic Polygonum-type and an helobial endosperm formation. Also, the time-lapse of the developmental processes studied was recorded.

Abnormal early cleavage events predict early embryo demise: sperm oxidative stress and early abnormal cleavage.

PubMed

Burruel, Victoria; Klooster, Katie; Barker, Christopher M; Pera, Renee Reijo; Meyers, Stuart

2014-10-13

Human embryos resulting from abnormal early cleavage can result in aneuploidy and failure to develop normally to the blastocyst stage. The nature of paternal influence on early embryo development has not been directly demonstrated although many studies have suggested effects from spermatozoal chromatin packaging, DNA damage, centriolar and mitotic spindle integrity, and plasma membrane integrity. The goal of this study was to determine whether early developmental events were affected by oxidative damage to the fertilizing sperm. Survival analysis was used to compare patterns of blastocyst formation based on P2 duration. Kaplan-Meier survival curves demonstrate that relatively few embryos with short (<1 hr) P2 times reached blastocysts, and the two curves diverged beginning on day 4, with nearly all of the embryos with longer P2 times reaching blastocysts by day 6 (p < .01). We determined that duration of the 2nd to 3rd mitoses were sensitive periods in the presence of spermatozoal oxidative stress. Embryos that displayed either too long or too short cytokineses demonstrated an increased failure to reach blastocyst stage and therefore survive for further development. Although paternal-derived gene expression occurs later in development, this study suggests a specific role in early mitosis that is highly influenced by paternal factors.

Efficient harvesting methods for early-stage snake and turtle embryos.

PubMed

Matsubara, Yoshiyuki; Kuroiwa, Atsushi; Suzuki, Takayuki

2016-04-01

Reptile development is an intriguing research target for understating the unique morphogenesis of reptiles as well as the evolution of vertebrates. However, there are numerous difficulties associated with studying development in reptiles. The number of available reptile eggs is usually quite limited. In addition, the reptile embryo is tightly adhered to the eggshell, making it a challenge to isolate reptile embryos intact. Furthermore, there have been few reports describing efficient procedures for isolating intact embryos especially prior to pharyngula stage. Thus, the aim of this review is to present efficient procedures for obtaining early-stage reptilian embryos intact. We first describe the method for isolating early-stage embryos of the Japanese striped snake. This is the first detailed method for obtaining embryos prior to oviposition in oviparous snake species. Second, we describe an efficient strategy for isolating early-stage embryos of the soft-shelled turtle. © 2016 Japanese Society of Developmental Biologists.

Extracting cardiac shapes and motion of the chick embryo heart outflow tract from four-dimensional optical coherence tomography images

NASA Astrophysics Data System (ADS)

Yin, Xin; Liu, Aiping; Thornburg, Kent L.; Wang, Ruikang K.; Rugonyi, Sandra

2012-09-01

Recent advances in optical coherence tomography (OCT), and the development of image reconstruction algorithms, enabled four-dimensional (4-D) (three-dimensional imaging over time) imaging of the embryonic heart. To further analyze and quantify the dynamics of cardiac beating, segmentation procedures that can extract the shape of the heart and its motion are needed. Most previous studies analyzed cardiac image sequences using manually extracted shapes and measurements. However, this is time consuming and subject to inter-operator variability. Automated or semi-automated analyses of 4-D cardiac OCT images, although very desirable, are also extremely challenging. This work proposes a robust algorithm to semi automatically detect and track cardiac tissue layers from 4-D OCT images of early (tubular) embryonic hearts. Our algorithm uses a two-dimensional (2-D) deformable double-line model (DLM) to detect target cardiac tissues. The detection algorithm uses a maximum-likelihood estimator and was successfully applied to 4-D in vivo OCT images of the heart outflow tract of day three chicken embryos. The extracted shapes captured the dynamics of the chick embryonic heart outflow tract wall, enabling further analysis of cardiac motion.

Apoptosis generates mechanical forces that close the lens vesicle in the chick embryo

NASA Astrophysics Data System (ADS)

Oltean, Alina; Taber, Larry A.

2018-03-01

During the initial stages of eye development, optic vesicles grow laterally outward from both sides of the forebrain and come into contact with the surrounding surface ectoderm (SE). Within the region of contact, these layers then thicken locally to create placodes and invaginate to form the optic cup (primitive retina) and lens vesicle (LV), respectively. This paper examines the biophysical mechanisms involved in LV formation, which consists of three phases: (1) lens placode formation; (2) invagination to create the lens pit (LP); and (3) closure to form a complete ellipsoidally shaped LV. Previous studies have suggested that extracellular matrix deposited between the SE and optic vesicle causes the lens placode to form by locally constraining expansion of the SE as it grows, while actomyosin contraction causes this structure to invaginate. Here, using computational modeling and experiments on chick embryos, we confirm that these mechanisms for Phases 1 and 2 are physically plausible. Our results also suggest, however, that they are not sufficient to close the LP during Phase 3. We postulate that apoptosis provides an additional mechanism by removing cells near the LP opening, thereby decreasing its circumference and generating tension that closes the LP. This hypothesis is supported by staining that shows a ring of cell death located around the LP opening during closure. Inhibiting apoptosis in cultured embryos using caspase inhibitors significantly reduced LP closure, and results from a finite-element model indicate that closure driven by cell death is plausible. Taken together, our results suggest an important mechanical role for apoptosis in lens development.

Mechanical origins of rightward torsion in early chick brain development

NASA Astrophysics Data System (ADS)

Chen, Zi; Guo, Qiaohang; Dai, Eric; Taber, Larry

2015-03-01

During early development, the neural tube of the chick embryo undergoes a combination of progressive ventral bending and rightward torsion. This torsional deformation is one of the major organ-level left-right asymmetry events in development. Previous studies suggested that bending is mainly due to differential growth, however, the mechanism for torsion remains poorly understood. Since the heart almost always loops rightwards that the brain twists, researchers have speculated that heart looping affects the direction of brain torsion. However, direct evidence is lacking, nor is the mechanical origin of such torsion understood. In our study, experimental perturbations show that the bending and torsional deformations in the brain are coupled and that the vitelline membrane applies an external load necessary for torsion to occur. Moreover, the asymmetry of the looping heart gives rise to the chirality of the twisted brain. A computational model and a 3D printed physical model are employed to help interpret these findings. Our work clarifies the mechanical origins of brain torsion and the associated left-right asymmetry, and further reveals that the asymmetric development in one organ can induce the asymmetry of another developing organ through mechanics, reminiscent of D'Arcy Thompson's view of biological form as ``diagram of forces''. Z.C. is supported by the Society in Science - Branco Weiss fellowship, administered by ETH Zurich. L.A.T acknowledges the support from NIH Grants R01 GM075200 and R01 NS070918.

PITX2 and NODAL expression during axis formation in the early rabbit embryo.

PubMed

Plöger, Ruben; Viebahn, Christoph

2018-04-26

Attaining molecular and morphological axial polarity during gastrulation is a fundamental early requirement for normal development of the embryo. In mammals, the first morphological sign of the anterior-posterior axis appears anteriorly in the form of the anterior marginal crescent (or anterior visceral endoderm) while in the avian the first such sign is the Koller's sickle at the posterior pole of the embryonic disc. Despite this inverse mode of axis formation many genes and molecular pathways involved in various steps of this process seem to be evolutionary conserved amongst amniotes, the nodal gene being a well-known example with its functional involvement prior and during gastrulation. The pitx2 gene, however, is a new candidate described in the chick as an early marker for anterior-posterior polarity and as regulator of axis formation including twinning. To find out whether pitx2 has retained its inductive and early marker function during the evolution of mammals, this study analyzes pitx2 and nodal expression at parallel stages during formation of the anterior-posterior polarity in the early rabbit embryo using whole-mount in situ hybridization and serial light-microscopical sections. At a late pre-gastrulation stage a localized reduction of nodal expression presages the position of the anterior pole of the embryonic disc and thus serves as the earliest molecular marker of anterior-posterior polarity known so far. pitx2 is expressed in a polarized manner in the anterior marginal crescent and in the posterior half of the embryonic disc during further development only while nodal expression in the anterior segment of the posterior pitx2 expression domain helps to define the so-called anterior streak domain (ASD), a novel progenitor region of the anterior half of the primitive streak. The expression patterns of both genes thus serve as signs of a conserved involvement in early axis formation in amniotes and, possibly, in twinning in mammals as well. Copyright �

Comparison of safety and immunogenicity of purified chick embryo cell vaccine using Zagreb and Essen regimens in patients with category II exposure in China.

PubMed

Hu, Quan; Liu, Man-Qing; Zhu, Zheng-Gang; Zhu, Ze-Rong; Lu, Sha

2014-01-01

The aim was to compare the safety and immunogenicity of purified chick embryo cell vaccine (PCECV) with Zagreb 2-1-1 and Essen 1-1-1-1-1 regimens in patients with WHO category II exposure in China. Side effects including systemic and local symptoms were recorded for all patients during vaccination with purified chick embryo cell vaccine (PCECV) under Zagreb 2-1-1 or Essen 1-1-1-1-1 regimens, and the rabies neutralization antibody titers in patients' serum at days 0, 7, 14, 45, 365 post-immunization were measured to determine the immunogenicity. Fever and pain were the most common events for systemic and local symptoms respectively, and most side effects (86.78%, 105/121) occurred after the first dose of vaccination. Safety analysis showed differences in side effects in<5-year-old patients between Zagreb and Essen regimens, especially after the first dose of vaccination (P = 0.043). Immunogenicity analysis indicated that Zagreb can achieve higher neutralization antibody titers and a greater seroconversion rate in a shorter time but had less persistence than Essen. When compared with the Essen regimen, the Zagreb regimen had a different immunogenicity in all study subjects, and different safety profile in young children, and a further study with a larger population and longer surveillance is warranted.

Tissue distribution of cells derived from the area opaca in heterospecific quail-chick blastodermal chimeras

PubMed Central

Karagenç, Levent; Sandikci, Mustafa

2010-01-01

The objective of the current study was to determine the tissue distribution of cells derived from the area opaca in heterospecific quail-chick blastodermal chimeras. Quail-chick chimeras were constructed by transferring dissociated cells from the area opaca of the stage X–XII (EG&K) quail embryo into the subgerminal cavity of the unincubated chick blastoderm. The distribution of quail cells in embryonic as well as extra-embryonic tissues of the recipient embryo were examined using the QCPN monoclonal antibody after 6 days of incubation in serial sections taken at 100-μm intervals. Data gathered in the present study demonstrated that, when introduced into the subgerminal cavity of a recipient embryo, cells of the area opaca are able to populate not only extra-embryonic structures such as the amnion and the yolk sac, but also various embryonic tissues derived from the ectoderm and less frequently the mesoderm. Ectodermal chimerism was confined mainly to the head region and was observed in tissues derived from the neural ectoderm and the surface ectoderm, including the optic cup, diencephalon and lens. Although the possibility of random incorporation of transplanted cells into these embryonic structures cannot be excluded, these results would suggest that area opaca, a peripheral ring of cells in the avian embryo destined to form the extra-embryonic ectoderm and endoderm of the yolk sac, might harbor cells that have the potential to give rise to various cell types in the recipient chick embryo, including those derived from the surface ectoderm and neural ectoderm. PMID:19900180

Establishment of a chick embryo shell-less culture system and its use to observe change in behavior caused by nicotine and substances from cigarette smoke.

PubMed

Hamamichi, S; Nishigori, H

2001-02-28

Early detection and removal of harmful factors are essential to the proper physical and psychological development of the fetus, presumably showing the effects during the prenatal period and after birth. As one procedure to aid in understanding such factors, we have established a shell-less culture system for video monitoring to observe change in behavior of 7-day-old chick embryos. Nicotine and aqueous cigarette smoke extract (ACSE) were selected for the present experiments, and the results showed a complete stoppage of swing-like movements by administrations of 10 microg nicotine and 1xACSE, possibly displaying paralytic symptoms. Quantitative analysis of nicotine in 1xACSE indicated that more than 10 microg of nicotine were contained in 100 microl of the extract. The present system, although in initial stage of development, may be a useful preliminary screening procedure for perhaps supervision and warning about the environment surrounding pregnant women.

Investigation of mRNA expression for secreted frizzled-related protein 2 (sFRP2) in chick embryos.

PubMed

Lin, Chung-Tien; Lin, Yu-Ting; Kuo, Tzong-Fu

2007-08-01

The roles of secreted frizzled-related protein 2 (sFRP2) in organ development of vertebrate animals are not well understood. We investigated expression of sFRP2 during embryogenesis of Arbor Acre broiler chicken eggs. Expression of sFRP2 was detected in the folds and lateral layer of developing brains. The sFRP2 signals in the developing eye were marked as a circle along the orbit. In younger embryos on days 3-6, the sFRP2 signals were consistent with growth of the sclerotome, suggesting that sFRP2 may be associated with somite development. Furthermore, with the exception of bones, sFRP2 mRNA was detectable in the interdigital tissue of embryos older than eight days as the limbs matured. This revealed that sFRP2 might play a role in myogenesis. In situ hybridization was also used to analyze the expression of sFRP2 in day 3-10 chick embryos. Signals were expressed in the gray matter of the developing brain coelom, including the optic lobe, metencephalon, myelencephalon, mesencephalon and diencephalon. The developing eyes contained an intercellular distribution of sFRP2 in the pigmented layer of the retina and photoreceptors. Furthermore, sFRP2 was expressed in the mantle layer of the neural tube and notochord. Based on these findings, it seems reasonable to suggest that sFRP2 may play an active role in embryogenesis, especially in development of the neural system, eyes, muscles and limbs.

Simultaneous real-time quantification of blood flow and vascular growth in the chick embryo using optical coherence tomography

NASA Astrophysics Data System (ADS)

Kowalski, William J.; Teslovich, Nikola C.; Chen, Chia-Yuan; Keller, Bradley B.; Pekkan, Kerem

2014-03-01

Experimental and clinical data indicate that hemodynamic forces within the embryo provide critical biomechanical cues for cardiovascular morphogenesis, growth, and remodeling and that perturbed flow is a major etiology of congenital heart disease. However, embryonic flow-growth relationships are largely qualitative and poorly defined. In this work, we provide a quantitative analysis of in vivo flow and growth trends in the chick embryo using optical coherence tomography (OCT) to acquire simultaneous velocity and structural data of the right vitelline artery continuously over a ten hour period beginning at stage 16 (hour 54). We obtained 3D vessel volumes (15 μm lateral, 4.3 μm axial resolutions, 6 μm slice spacing) at 60 minute intervals, taking a B-scan time series totaling one cardiac cycle at each slice. Embryos were maintained at a constant 37°C and 60% humidity during the entire acquisition period through an inhouse built chamber. The 3D vessel lumen geometries were reconstructed manually to assess growth. Blood flow velocity was computed from the central B-scan using red blood cell particle image velocimetry. The use of extended OCT imaging as a non-invasive method for continuous and simultaneous flow and structural data can enhance our understanding of the biomechanical regulation of critical events in morphogenesis. Data acquired will be useful to validate predictive finite-element 3D growth models.

Exposure of chick embryos to cadmium changes the extra-embryonic vascular branching pattern and alters expression of VEGF-A and VEGF-R2

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

Gheorghescu, Anna Kaskova; Tywoniuk, Bartlomiej; Complex and Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4

Cadmium (Cd) has several industrial applications, and is found in tobacco products, a notable source of human exposure. Vascular endothelial cells are key targets of Cd toxicity. Here, we aim to quantify the alteration to vascular branching pattern following Cd exposure in the chick extra-embryonic membrane (EEM) using fractal analysis, and explore molecular cues to angiogenesis such as VEGF-A and VEGF-R2 expression following Cd treatment. Chicken embryos were incubated for 60 h to Hamburger–Hamilton developmental stage 16–17, then explanted and treated with 50 μL of 50 μmol cadmium acetate (CdAc) or an equivalent volume of equimolar sodium acetate (NaAc). Imagesmore » of embryos and their area vasculosa (AV) were captured and analyzed at 4 different time points (4, 8, 24 and 48 h) following treatment. Vascular branching in the AV was quantified using its fractal dimension (D{sub f}), estimated using a box counting method. Gallinaceous VEGF ELISA was used to measure the VEGF-A concentration in the EEM following treatment, with determination of the relative expression of VEGF-A and VEGF-R2 using quantitative real-time RT-PCR. Vascular branching increased monotonically in the control group at all time points. The anti-angiogenic effect of Cd exposure on the AV was reflected by a significant reduction in D{sub f} when compared with controls. D{sub f} was more markedly reduced in cultures with abnormal embryos. The expression of VEGF-A protein, and VEGF-A and VEGF-R2 mRNA were reduced in Cd-exposed EEMs. Both molecules contribute to growth, vessel sprouting and branching processes, which supports our findings using fractal analysis. - Highlights: • The chick area vasculosa was undersized in embryos exposed to 50 μM cadmium acetate. • Fractal dimension was reduced in the AV after Cd exposure, indicating decreased branching. • VEGF-A protein was decreased in Cd-treated extraembryonic membranes. • VEGF-A and VEGF-R2 mRNA was decreased in Cd

Prenatal sensory experience affects hatching behavior in domestic chicks (Gallus gallus) and Japanese quail chicks (Coturnix coturnix japonica).

PubMed

Sleigh, Merry J; Casey, Michael B

2014-07-01

Species-typical developmental outcomes result from organismic and environmental constraints and experiences shared by members of a species. We examined the effects of enhanced prenatal sensory experience on hatching behaviors by exposing domestic chicks (n = 95) and Japanese quail (n = 125) to one of four prenatal conditions: enhanced visual stimulation, enhanced auditory stimulation, enhanced auditory and visual stimulation, or no enhanced sensory experience (control condition). In general, across species, control embryos had slower hatching behaviors than all other embryos. Embryos in the auditory condition had faster hatching behaviors than embryos in the visual and control conditions. Auditory-visual condition embryos showed similarities to embryos exposed to either auditory or visual stimulation. These results suggest that prenatal sensory experience can influence hatching behavior of precocial birds, with the type of stimulation being a critical variable. These results also provide further evidence that species-typical outcomes are the result of species-typical prenatal experiences. © 2013 Wiley Periodicals, Inc.

Transformation of primary chick embryo fibroblasts by Marek's disease virus.

PubMed

Buranathai, C; Rodriguez, J; Grose, C

1997-12-08

Marek's disease virus (MDV) is an alphaherpesvirus, which can mediate the malignant transformation of lymphocytes to form lymphomas in chickens. In this study, we demonstrate that MDV can transform primary chick embryo fibroblasts (CEF). The cell line derived from primary CEF infected with the GA strain of MDV was called CEM(MDV). The fibroblast nature of CEM(MDV) was verified by absence of cytokeratin type II. The CEM(MDV) phenotype differed from either primary CEF or MDV-infected CEF. CEM(MDV) were extensively vacuolated, with unusual multilamellar structures in the cytoplasm, The nuclei were considerably larger than those in primary CEF and were uniformly positive for proliferating cell nuclear antigen. The cell line was subcultured for more than 10 generations; however, CEM(MDV) did not support a fully productive MDV infection, because complete nucleocapsids were not detected and infectivity assays showed that cell line produced no infectious virus. PCR analyses demonstrated that this cell line carried both polypeptide 38 (pp38) and Meq DNA, MDV-specific genes associated with transformation. In addition, examination by laser scanning confocal microscopy revealed that CEM(MDV) constitutively produced MDV MEQ protein in nuclei and pp38 as well as glycoprotein B in the cytoplasm and on the plasma membrane. Growth in soft agar assay demonstrated that CEM(MDV) formed colonies, similar to HeLa and human melanoma cells. Retroviral insertion was not detected in DNA from the CEM(MDV) line.

[Association of human chorionic gonadotropin level in embryo culture media with early embryo development].

PubMed

Wang, Haiying; Zhang, Renli; Han, Dong; Liu, Caixia; Cai, Jiajie; Bi, Yanling; Wen, Anmin; Quan, Song

2014-06-01

To investigate the association of human chorionic gonadotropin (HCG) level on day 3 of embryo culture with embryo development. Spent culture media were collected from individually cultured embryos on day 3 of in vitro fertilization and embryo transfer (IVF-ET) cycles. HCG concentration in the culture media was measured using an ELISA kit and its association with embryo development was assessed. In the 163 samples of embryo culture media from 60 patients, HCG was positive in 153 sample (93.8%) with a mean level of 0.85 ± 0.43 mIU/ml. The concentration of hCG in the culture media increased gradually as the number of blastomeres increased (F=2.273, P=0.03), and decreased as the morphological grade of the embryo was lowered (F=3.900, P=0.02). ELISA is capable of detecting HCG levels in spent culture media of embryos on day 3 of in vitro culture. The concentration of HCG in spent culture media is positively correlated with the status of early embryo development and implantation rate and thus serves as a useful marker for embryo selection in IVF-ET procedure.

Integrating toxicity risk in bird eggs and chicks: using chick down feathers to estimate mercury concentrations in eggs.

PubMed

Ackerman, Joshua T; Eagles-Smith, Collin A

2009-03-15

The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5-32.4 microg g(-1) fw) and eggs (0.04-2.79 microg g(-1) fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n=94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n=28, r2 = 0.79). Down feather Hg in recaptured chicks (< or =10 days old) was correlated with down feather Hg at hatching (< or =3 days old; n=88, r2 = 0.74). Our results demonstrate the utility of using down feathers of chicks < or =10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg's effects on both egg hatchability and subsequent chick mortality.

Integrating toxicity risk in bird eggs and chicks: Using chick down feathers to estimate mercury concentrations in eggs

USGS Publications Warehouse

Ackerman, Joshua T.; Eagles-Smith, Collin A.

2009-01-01

The concentration of mercury (Hg) in eggs that causes reduced hatching success is regarded as a critical end point for Hg toxicity in birds. However, incorporating effects of in ovo mercury exposure on chick health and survival could improve risk assessment. We developed equations to predict Hg in eggs using Hg in chick down feathers, and vice versa, by assessing the relationship between Hg in feathers (0.5−32.4 μg g−1 fw) and eggs (0.04−2.79 μg g−1 fww) for three waterbird species in San Francisco Bay, CA. Feather Hg sampled from embryos of pipping eggs was highly correlated with fresh whole-egg Hg (n = 94, r2 = 0.96). Additionally, using an egg microsampling technique, albumen Hg was correlated with feather Hg sampled from chicks in the same nest (n = 28, r2 = 0.79). Down feather Hg in recaptured chicks (≤10 days old) was correlated with down feather Hg at hatching (≤3 days old; n = 88, r2 = 0.74). Our results demonstrate the utility of using down feathers of chicks ≤10 days of age to nonlethally predict Hg in eggs and thus provide the ability to develop exposure thresholds for eggs that incorporate in ovo Hg’s effects on both egg hatchability and subsequent chick mortality.

Expression of renin–angiotensin system components in the early bovine embryo

PubMed Central

Pijacka, Wioletta; Hunter, Morag G; Broughton Pipkin, Fiona; Luck, Martin R

2012-01-01

The renin–angiotensin system (RAS), mainly associated with the regulation of blood pressure, has been recently investigated in female reproductive organs and the developing foetus. Angiotensin II (Ang II) influences oviductal gamete movements and foetal development, but there is no information about RAS in the early embryo. The aim of this study was to determine whether RAS components are present in the pre-implantation embryo, to determine how early they are expressed and to investigate their putative role at this stage of development. Bovine embryos produced in vitro were used for analysis of RAS transcripts (RT-PCR) and localisation of the receptors AGTR1 and AGTR2 (immunofluorescent labelling). We also investigated the effects of Ang II, Olmesartan (AGTR1 antagonist) and PD123319 (AGTR2 antagonist) on oocyte cleavage, embryo expansion and hatching. Pre-implanted embryos possessed AGTR1 and AGTR2 but not the other RAS components. Both receptors were present in the trophectoderm and in the inner cell mass of the blastocyst. AGTR1 was mainly localised in granular-like structures in the cytoplasm, suggesting its internalisation into clathrin-coated vesicles, and AGTR2 was found mainly in the nuclear membrane and in the mitotic spindle of dividing trophoblastic cells. Treating embryos with PD123319 increased the proportion of hatched embryos compared with the control. These results, the first on RAS in the early embryo, suggest that the pre-implanted embryo responds to Ang II from the mother rather than from the embryo itself. This may be a route by which the maternal RAS influences blastocyst hatching and early embryonic development. PMID:23781300

Experimental analysis of control mechanisms in somite segmentation in avian embryos. II. Reduction of material in the gastrula stages of the chick.

PubMed

Bellairs, R; Veini, M

1984-02-01

A new theory of control of somite segmentation in chick embryos is proposed. This supposses that tiny clusters of already programmed cells are present throughout the presumptive somite area at stage 4, but that in order to fulfill their destiny they probably depend on the addition of further cells from the primitive streak. Evidence is based on the two groups of experiments: a) Experiments involving transection across the primitive streak at various stages, (which results in a 'tail' which possesses mesodermal derivatives) and across the segmental plate (which results in a 'tail' lacking mesodermal derivatives). b) Experiments in which parts of embryos have been explanted with or without their primitive streak. It is suggested that the initial clusters of pre-programmed cells move further and further posteriorly, developing into somitomeres (the precursors of true somites) only as they receive re-inforcements from the primitive streak or, ultimately, from the tail bud.

Green Light-emitting Diodes Light Stimuli during Incubation Enhances Posthatch Growth without Disrupting Normal Eye Development of Broiler Embryos and Hatchlings.

PubMed

Zhang, L; Zhu, X D; Wang, X F; Li, J L; Gao, F; Zhou, G H

2016-11-01

Monochromatic green light-emitting diodes (LED) light stimuli influences the posthatch growth performance of chicks. This study was undertaken with the following objectives: i) to examine whether the green LED light stimuli induces an overheating effect by determining weight loss rate of fertile eggs during incubation period; ii) to look for the development of eyes and other primary organs at different ages of embryos and newly hatched chicks. Arbor Acres fertile broiler eggs (n = 480) were randomly assigned to 3 incubation groups and exposed to continuous white light, green light, or a dark environment (control) from the first day to 19 d of incubation. The light sourced from LED lamps with the intensity of 30 lx at eggshell level. The results showed that either green or white light stimuli during incubation did not significantly affect the weight loss rate of fertile eggs, hatching time, hatchability, chick embryo, or body weight (BW), the weight percentage of heart, liver, and eyes, as well as obvious systematic abnormalities in eye weight, side-to-side, back-to-front, or corneal diameter from 15 d of embryogenesis to 6 d of posthatch (p>0.05). Compared with the dark condition, green light stimuli during incubation tended to increase feed intake (p = 0.080), improved the BW gain of chicks during 0 to 6 day posthatch (p<0.05), and increased the percentage of pectoral muscle to the BW on 3- and 6-day-old chicks. In addition, embryos or chicks in green light had lower weight percentage of yolk retention on 19 d of embryogenesis and 1 d of posthatch in comparison to those in dark or white group (p<0.05). These results suggest that providing 30 lx green LED light stimuli during incubation has no detrimental effect on the development of eyes, heart and liver of embryos and hatchlings, but does have potential benefits in terms of enhancement of the chick growth during the early posthatch stages. In addition, the fertile broiler eggs stimulated with 30 lx green LED

Efficacy of early chick nutrition with Aloe vera and Azadirachta indica on gut health and histomorphometry in chicks.

PubMed

Sujatha, Tamilvanan; Abhinaya, Sivasankar; Sunder, Jai; Thangapandian, Marudhai; Kundu, Anandamoy

2017-06-01

This study was conducted with an aim of studying the efficacy of water supplements of Aloe vera and Azadirachta indica (neem) during pre-starter age (0-2 weeks) on gut health and histomorphometry in Vanaraja chicks. A total of 192 day old Vanaraja chicks were randomly assigned to one of four herbal water treatments throughout the experimental pre-starter stage (0-2 weeks) in a completely randomized design. Each treatment was given four replicates consisting of 12 chicks per replicate. Water treatments comprised T1: Control with regular antibiotic supplement, T2: 3 ml Aloe juice per chick per day, T3: 3 ml neem extract per chick per day, T4: 1.5 ml Aloe and 1.5 ml neem per chick per day. Gut culture was done for Escherichia coli and Lactobacillus sps. and gut histomorphometry in 24 gut samples at 14 days of age. This study revealed that supplementation of A. vera and neem in water significantly (p<0.05) reduced and increased the number of gut E. coli and Lactobacillus sps. Colonies, respectively, as compared to that of control groups; Villi was significantly (p<0.05) taller and broader on 14 days of age across the jejunum of chicks fed with neem supplementation as compared to that of control chicks. Significantly lower crypt depth (p<0.05) was observed in the duodenum of Aloe supplementation. Villus height: Crypt depth ratio of duodenum and jejunum was significantly (p<0.05) increased neem and Aloe supplementation in chicks as compared to their combination and control. Immediate post hatch supplementation of Aloe juice and neem extract in chicks improved the development and health of their gut.

Tissue morphodynamics shaping the early mouse embryo.

PubMed

Sutherland, Ann E

2016-07-01

Generation of the elongated vertebrate body plan from the initially radially symmetrical embryo requires comprehensive changes to tissue form. These shape changes are generated by specific underlying cell behaviors, coordinated in time and space. Major principles and also specifics are emerging, from studies in many model systems, of the cell and physical biology of how region-specific cell behaviors produce regional tissue morphogenesis, and how these, in turn, are integrated at the level of the embryo. New technical approaches have made it possible more recently, to examine the morphogenesis of the mouse embryo in depth, and to elucidate the underlying cellular mechanisms. This review focuses on recent advances in understanding the cellular basis for the early fundamental events that establish the basic form of the embryo. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of PCOS on early embryo cleavage kinetics.

PubMed

Wissing, M L; Bjerge, M R; Olesen, A I G; Hoest, T; Mikkelsen, A L

2014-04-01

This study investigated whether polycystic ovary syndrome (PCOS) affected early embryo development assessed by time-lapse analysis of embryo kinetics from fertilization to the blastocyst stage. This was a prospective cohort study of two pronuclei (2PN) embryos from 25 hyperandrogenic PCOS patients (110 2PN embryos), 26 normoandrogenic PCOS patients (140 2PN embryos) and 20 healthy, regularly cycling women (controls, 97 2PN embryos). Patients underwent the same baseline evaluation and the same ovarian stimulation from April 2010 to February 2013. Oocytes were fertilized by intracytoplasmic sperm injection and incubated in an EmbryoScope with pictures taken every 20 min in seven focal planes. Time to 2PN breakdown, first cleavage and cleavage to 3, 4, 5, 6, 7 and 8 cells, morula and blastocyst (t₂, t₃, t₄, t₅, t₆, t₇, t₈, t(M), t(B)) were annotated. Differences in embryo kinetics between groups were assessed by mixed modelling. Compared with controls, embryos from hyperandrogenic PCOS patients were significantly delayed at 2PN breakdown, t₂, t₃, t₄ and t₇ but not at t₅, t₆, t₈, t(M) or t(B). Embryos from hyperandrogenic PCOS women had developed slower from fertilization to the 8-cell stage compared with embryos from controls. Copyright © 2014 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

Microgravity in the STS-29 space shuttle discovery affected the vestibular system of chick embryos

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Martin, D.; Jones, T.; Vellinger, J.; Deuser, M.; Hester, P.; Hullinger, R.

1996-01-01

Out of 32 embryos flown (16 @ E2 + 16 @ E9) for 5 days, 16 survived. All sixteen E2 were dead at landing. Eight were opened and eight were incubated at 1.0G. Autopsy showed that 4 E2 survived over 24 hours in space. Eight E14 hatched without anatomical malformations, and 8 E14 were fixed. The height of the macular epithelia was 31 mu m (mean) in control and 26 mu m in flight chicks. The cross-sectional area of macular nuclei of control was 17 mu m(2) for hair cells and 14 mu m(2) in supporting cells. In flight, cross-sectional area was 17 mu m(2) in hair cells and 15 mu m(2) in supporting cells (n=250). The shape factor of cartilage cells (1.0 = perfect circle) between control (mean = 0.70) and flight (mean = 0.72), and the area of cartilaginous cells between controls (mean = 9 mu m(2)) and flight (mean = 9 mu m(2)) did not differ (n=300). The nuclei of support cells were closer to the basement membrane in flight than in control chicks. The immunoreactivity of otoconia with anti keratan, fibronectin or chrondroitin sulfate was not different between flight and control ears. There were more afferent fibers inside the macular epithelia of flight (p<0.05) than control. Three of 8 flight animals had elevated vestibular thresholds (VT), with normal mean response amplitudes and latencies. Modified afferent innervation patterns requiring weeks to compensate are sufficient to elevate VT, and should be investigated further. Other reversible (sublethal) microgravity effects on sensory epithelia (vacuoles, swelling, etc) require quantification.

Effects of Optically Imposed Astigmatism on Early Eye Growth in Chicks

PubMed Central

Chu, Chin Hung Geoffrey; Kee, Chea Su

2015-01-01

Purpose To determine the effects of optically imposed astigmatism on early eye growth in chicks. Methods 5-day-old (P5) White Leghorn chicks were randomly assigned to either wear, monocularly, a “high magnitude” (H: +4.00DS/-8.00DC) crossed-cylindrical lens oriented at one of four axes (45, 90, 135, and 180; n = 20 in each group), or were left untreated (controls; n = 8). Two additional groups wore a “low magnitude” (L: +2.00DS/−4.00DC) cylindrical lens orientated at either axis 90 or 180 (n = 20 and n = 18, respectively). Refractions were measured at P5 and after 7 days of treatment for all chicks (P12), whereas videokeratography and ex-vivo eyeshape analysis were performed at P12 for a subset of chicks in each group (n = 8). Results Compared to controls, chicks in the treatment groups developed significant amounts of refractive astigmatism (controls: 0.03±0.22DC; treatment groups: 1.34±0.22DC to 5.51±0.26DC, one-way ANOVAs, p≤0.05) with axes compensatory to those imposed by the cylindrical lenses. H cylindrical lenses induced more refractive astigmatism than L lenses (H90 vs. L90: 5.51±0.26D vs. 4.10±0.16D; H180 vs. L180: 2.84±0.44D vs. 1.34±0.22D, unpaired two-sample t-tests, both p≤0.01); and imposing with-the-rule (H90 and L90) and against-the-rule astigmatisms (H180 and L180) resulted in, respectively, steeper and flatter corneal shape. Both corneal and internal astigmatisms were moderately to strongly correlated with refractive astigmatisms (Pearson’s r: +0.61 to +0.94, all p≤0.001). In addition, the characteristics of astigmatism were significantly correlated with multiple eyeshape parameters at the posterior segments (Pearson’s r: -0.27 to +0.45, all p≤0.05). Conclusions Chicks showed compensatory ocular changes in response to the astigmatic magnitudes imposed in this study. The correlations of changes in refractive, corneal, and posterior eyeshape indicate the involvement of anterior and posterior ocular segments during the

Efficacy of early chick nutrition with Aloe vera and Azadirachta indica on gut health and histomorphometry in chicks

PubMed Central

Sujatha, Tamilvanan; Abhinaya, Sivasankar; Sunder, Jai; Thangapandian, Marudhai; Kundu, Anandamoy

2017-01-01

Aim: This study was conducted with an aim of studying the efficacy of water supplements of Aloe vera and Azadirachta indica (neem) during pre-starter age (0-2 weeks) on gut health and histomorphometry in Vanaraja chicks. Materials and Methods: A total of 192 day old Vanaraja chicks were randomly assigned to one of four herbal water treatments throughout the experimental pre-starter stage (0-2 weeks) in a completely randomized design. Each treatment was given four replicates consisting of 12 chicks per replicate. Water treatments comprised T1: Control with regular antibiotic supplement, T2: 3 ml Aloe juice per chick per day, T3: 3 ml neem extract per chick per day, T4: 1.5 ml Aloe and 1.5 ml neem per chick per day. Gut culture was done for Escherichia coli and Lactobacillus sps. and gut histomorphometry in 24 gut samples at 14 days of age. Results: This study revealed that supplementation of A. vera and neem in water significantly (p<0.05) reduced and increased the number of gut E. coli and Lactobacillus sps. Colonies, respectively, as compared to that of control groups; Villi was significantly (p<0.05) taller and broader on 14 days of age across the jejunum of chicks fed with neem supplementation as compared to that of control chicks. Significantly lower crypt depth (p<0.05) was observed in the duodenum of Aloe supplementation. Villus height: Crypt depth ratio of duodenum and jejunum was significantly (p<0.05) increased neem and Aloe supplementation in chicks as compared to their combination and control. Conclusion: Immediate post hatch supplementation of Aloe juice and neem extract in chicks improved the development and health of their gut. PMID:28717305

Developmental imaging: the avian embryo hatches to the challenge.

PubMed

Kulesa, Paul M; McKinney, Mary C; McLennan, Rebecca

2013-06-01

The avian embryo provides a multifaceted model to study developmental mechanisms because of its accessibility to microsurgery, fluorescence cell labeling, in vivo imaging, and molecular manipulation. Early two-dimensional planar growth of the avian embryo mimics human development and provides unique access to complex cell migration patterns using light microscopy. Later developmental events continue to permit access to both light and other imaging modalities, making the avian embryo an excellent model for developmental imaging. For example, significant insights into cell and tissue behaviors within the primitive streak, craniofacial region, and cardiovascular and peripheral nervous systems have come from avian embryo studies. In this review, we provide an update to recent advances in embryo and tissue slice culture and imaging, fluorescence cell labeling, and gene profiling. We focus on how technical advances in the chick and quail provide a clearer understanding of how embryonic cell dynamics are beautifully choreographed in space and time to sculpt cells into functioning structures. We summarize how these technical advances help us to better understand basic developmental mechanisms that may lead to clinical research into human birth defects and tissue repair. Copyright © 2013 Wiley Periodicals, Inc.

Establishment of left–right asymmetry in vertebrate development: the node in mouse embryos

PubMed Central

Komatsu, Yoshihiro

2014-01-01

Establishment of vertebrate left–right asymmetry is a critical process for normal embryonic development. After the discovery of genes expressed asymmetrically along the left–right axis in chick embryos in the mid 1990s, the molecular mechanisms responsible for left–right patterning in vertebrate embryos have been studied extensively. In this review article, we discuss the mechanisms by which the initial symmetry along the left–right axis is broken in the mouse embryo. We focus on the role of primary cilia and molecular mechanisms of ciliogenesis at the node when symmetry is broken and left–right asymmetry is established. The node is considered a signaling center for early mouse embryonic development, and the results we review here have led to a better understanding of how the node functions and establishes left–right asymmetry. PMID:23771646

Establishment of left-right asymmetry in vertebrate development: the node in mouse embryos.

PubMed

Komatsu, Yoshihiro; Mishina, Yuji

2013-12-01

Establishment of vertebrate left-right asymmetry is a critical process for normal embryonic development. After the discovery of genes expressed asymmetrically along the left-right axis in chick embryos in the mid 1990s, the molecular mechanisms responsible for left-right patterning in vertebrate embryos have been studied extensively. In this review article, we discuss the mechanisms by which the initial symmetry along the left-right axis is broken in the mouse embryo. We focus on the role of primary cilia and molecular mechanisms of ciliogenesis at the node when symmetry is broken and left-right asymmetry is established. The node is considered a signaling center for early mouse embryonic development, and the results we review here have led to a better understanding of how the node functions and establishes left-right asymmetry.

Early age thermal conditioning immediately reduces body temperature of broiler chicks in a tropical environment.

PubMed

De Basilio, V; Requena, F; León, A; Vilariño, M; Picard, M

2003-08-01

Early age thermal conditioning (TC) durably improves resistance of broilers to heat stress and reduces body temperature (Tb). Three experiments on broiler chicks were conducted to evaluate the effects of TC at 5 d of age on Tb variation measured by thermometer between 4 and 7 d of age, under a tropical environment. Because manipulation of chickens to measure Tb with a thermometer may increase Tb, a preliminary experiment on 13 3-to-4-wk-old male broilers compared Tb measured by telemetry to Tb measured in the terminal colon during three successive periods at 22, 33, and 22 degrees C. During heat exposure, Tb rapidly increased by 0.9 degrees C and plateaued over 24 h. During the last period, seven of the broilers rapidly reduced Tb to a plateau lower than the initial Tb, although six broilers exhibited more variable Tb. Measurement by thermometer underestimated on average core Tb by 0.28 degrees C at 22 degrees C and by 0.57 degrees C at 33 degrees C, whereas Tb recorded by telemetry was not affected by manipulation of the chickens. TC reduced Tb 24 h later in the three experiments. Compared to unexposed control chicks (N), 12 h of TC at 40 degrees C did not significantly reduce Tb at 7 d of age, although 24 h did. TC at 38 and 40 degrees C over 24 h significantly reduced Tb variation from 4 to 7 d of age compared to N chicks, whereas 36 degrees C did not. Withdrawing feed from the chicks for 2 h prior to measurement did not significantly reduce Tb at 4 and 7 d of age, but Tb reduction due to TC was greater in fed chicks (0.28 degrees C) than in chicks without feed (0.05 degrees C). Early age thermal conditioning at 38 to 40 degrees C at 5 d of age for 24 h reduced body temperature of 7-d-old male broilers.

Experimental tumor growth of canine osteosarcoma cell line on chick embryo chorioallantoic membrane (in vivo studies).

PubMed

Walewska, Magdalena; Dolka, Izabella; Małek, Anna; Wojtalewicz, Anna; Wojtkowska, Agata; Żbikowski, Artur; Lechowski, Roman; Zabielska-Koczywąs, Katarzyna

2017-05-12

The chick embryo chorioallantoic membrane (CAM) model is extensively used in human medicine in preclinical oncological studies. The CAM model has several advantages: low cost, simple experimental approach, time saving and following "3R principles". Research has shown that the human osteosarcoma cell lines U2OS, MMNG-HOS, and SAOS can form tumors on the CAM. In veterinary medicine, this has been described only for feline fibrosarcomas, feline mammary carcinomas and canine osteosarcomas. However, in case of canine osteosarcomas, it has been shown that only non-adherent osteosarcoma stem cells isolated from KTOSA5 and CSKOS cell lines have the ability to form microtumors on the CAM after an incubation period of 5 days, in contrast to adherent KTOSA5 and CSKOS cells. In the presented study, we have proven that the commercial adherent canine osteosarcoma cell line (D-17) can form vascularized tumors on the CAM after the incubation period of 10 days.

Extra-embryonic tissue spreading directs early embryo morphogenesis in killifish

PubMed Central

Reig, Germán; Cerda, Mauricio; Sepúlveda, Néstor; Flores, Daniela; Castañeda, Victor; Tada, Masazumi; Härtel, Steffen; Concha, Miguel L.

2017-01-01

The spreading of mesenchymal-like cell layers is critical for embryo morphogenesis and tissue repair, yet we know little of this process in vivo. Here we take advantage of unique developmental features of the non-conventional annual killifish embryo to study the principles underlying tissue spreading in a simple cellular environment, devoid of patterning signals and major morphogenetic cell movements. Using in vivo experimentation and physical modelling we reveal that the extra-embryonic epithelial enveloping cell layer, thought mainly to provide protection to the embryo, directs cell migration and the spreading of embryonic tissue during early development. This function relies on the ability of embryonic cells to couple their autonomous random motility to non-autonomous signals arising from the expansion of the extra-embryonic epithelium, mediated by cell membrane adhesion and tension. Thus, we present a mechanism of extra-embryonic control of embryo morphogenesis that couples the mechanical properties of adjacent tissues in the early killifish embryo. PMID:28580937

Wounded cells drive rapid epidermal repair in the early Drosophila embryo

PubMed Central

Fernandez-Gonzalez, Rodrigo; Zallen, Jennifer A.

2013-01-01

Epithelial tissues are protective barriers that display a remarkable ability to repair wounds. Wound repair is often associated with an accumulation of actin and nonmuscle myosin II around the wound, forming a purse string. The role of actomyosin networks in generating mechanical force during wound repair is not well understood. Here we investigate the mechanisms of force generation during wound repair in the epidermis of early and late Drosophila embryos. We find that wound closure is faster in early embryos, where, in addition to a purse string around the wound, actomyosin networks at the medial cortex of the wounded cells contribute to rapid wound repair. Laser ablation demonstrates that both medial and purse-string actomyosin networks generate contractile force. Quantitative analysis of protein localization dynamics during wound closure indicates that the rapid contraction of medial actomyosin structures during wound repair in early embryos involves disassembly of the actomyosin network. By contrast, actomyosin purse strings in late embryos contract more slowly in a mechanism that involves network condensation. We propose that the combined action of two force-generating structures—a medial actomyosin network and an actomyosin purse string—contributes to the increased efficiency of wound repair in the early embryo. PMID:23985320

Contraction and stress-dependent growth shape the forebrain of the early chicken embryo.

PubMed

Garcia, Kara E; Okamoto, Ruth J; Bayly, Philip V; Taber, Larry A

2017-01-01

During early vertebrate development, local constrictions, or sulci, form to divide the forebrain into the diencephalon, telencephalon, and optic vesicles. These partitions are maintained and exaggerated as the brain tube inflates, grows, and bends. Combining quantitative experiments on chick embryos with computational modeling, we investigated the biophysical mechanisms that drive these changes in brain shape. Chemical perturbations of contractility indicated that actomyosin contraction plays a major role in the creation of initial constrictions (Hamburger-Hamilton stages HH11-12), and fluorescent staining revealed that F-actin is circumferentially aligned at all constrictions. A finite element model based on these findings shows that the observed shape changes are consistent with circumferential contraction in these regions. To explain why sulci continue to deepen as the forebrain expands (HH12-20), we speculate that growth depends on wall stress. This idea was examined by including stress-dependent growth in a model with cerebrospinal fluid pressure and bending (cephalic flexure). The results given by the model agree with observed morphological changes that occur in the brain tube under normal and reduced eCSF pressure, quantitative measurements of relative sulcal depth versus time, and previously published patterns of cell proliferation. Taken together, our results support a biphasic mechanism for forebrain morphogenesis consisting of differential contractility (early) and stress-dependent growth (late). Copyright © 2016 Elsevier Ltd. All rights reserved.

Mechanisms of reoxygenation-induced calcium overload in cultured chick embryo heart cells

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

Murphy, J.G.; Smith, T.W.; Marsh, J.D.

1988-06-01

We examined mechanisms by which Ca enters cultured myocardial cells during posthypoxic reoxygenation. Monolayer cultures of chick embryo ventricular cells were prepared from hearts 10 days in ovo. Cells were exposed to hypoxic conditions (PO/sub 2/ less than 1.5 Torr), and /sup 45/Ca uptake during subsequent reoxygenation was then examined in the absence and presence of modulators of Ca channel-dependent Ca entry and Na-Ca exchange. Modulation of Ca entry by free radical-scavenging enzymes was also examined. Hypoxia for 120 min followed by reoxygenation increased Ca content from 1.9 to 6.1 nmol/mg protein (P less than 0.05) at 30 min. Verapamilmore » (10(-5) M) added before reoxygenation reduced Ca overload to 3.1 +/- 0.2 nmol/mg protein (P less than 0.05), but both verapamil and BAY K 8644 were without effect on modulating Ca entry if added 30 min after reoxygenation. /sup 24/Na content of cells increased from 70 nmol/mg protein in control cells to 157 nmol/mg protein (P less than 0.05) after hypoxia and reoxygenation, favoring Ca entry via Na-Ca exchange. Dichlorobenzamil significantly ameliorated reoxygenation-induced Ca overload, as did catalase and superoxide dismutase. We conclude that reoxygenation-induced Ca overload is unlikely to occur via the Ca channel. It occurs in part via Na-Ca exchange and is substantially ameliorated by enzymatic O/sub 2/ free radical scavengers.« less

From the Cover: Exposing Imidacloprid Interferes With Neurogenesis Through Impacting on Chick Neural Tube Cell Survival.

PubMed

Liu, Meng; Wang, Guang; Zhang, Shi-Yao; Zhong, Shan; Qi, Guo-Long; Wang, Chao-Jie; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-Xiang; Yang, Xuesong

2016-09-01

As a neonicotinoid pesticide, imidacloprid is widely used to control insects in agriculture and fleas on domestic animals. However, it is not known whether imidacloprid exposure negatively affects neurogenesis during embryonic development. In this study, using a chick embryo model, we investigated the effects of imidacloprid exposure on neurogenesis at the earliest stage and during late-stage embryo development. Exposing HH0 chick embryos to imidacloprid in EC culture caused neural tube defects (NTDs) and neuronal differentiation dysplasia as determined by NF/Tuj1 labeling. Furthermore, we found that F-actin accumulation on the apical side of the neural tube was suppressed by exposure to imidacloprid, and the expression of BMP4 and Shh on the dorsal and ventral sides of the neural tubes, respectively, were also reduced, which in turn affects the dorsolateral hinge points during bending of the neural plate. In addition, exposure to imidacloprid reduced cell proliferation and increased cell apoptosis, as determined by pHIS3 labeling and TUNEL staining, respectively, also contributing to the malformation. We obtained similar results in late-stage embryos exposed to imidacloprid. Finally, a bioinformatics analysis was employed to determine which genes identified in this study were involved in NTDs. The experimental evidence and bioinformatics analysis suggested that imidacloprid exposure during chick embryo development could increase the risk of NTDs and neural dysplasia. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Exceptional preservation of tiny embryos documents seed dormancy in early angiosperms.

PubMed

Friis, Else Marie; Crane, Peter R; Pedersen, Kaj Raunsgaard; Stampanoni, Marco; Marone, Federica

2015-12-24

The rapid diversification of angiosperms through the Early Cretaceous period, between about 130-100 million years ago, initiated fundamental changes in the composition of terrestrial vegetation and is increasingly well understood on the basis of a wealth of palaeobotanical discoveries over the past four decades and their integration with improved knowledge of living angiosperms. Prevailing hypotheses, based on evidence both from living and from fossil plants, emphasize that the earliest angiosperms were plants of small stature with rapid life cycles that exploited disturbed habitats in open, or perhaps understorey, conditions. However, direct palaeontogical data relevant to understanding the seed biology and germination ecology of Early Cretaceous angiosperms are sparse. Here we report the discovery of embryos and their associated nutrient storage tissues in exceptionally well-preserved angiosperm seeds from the Early Cretaceous. Synchrotron radiation X-ray tomographic microscopy of the fossil embryos from many taxa reveals that all were tiny at the time of dispersal. These results support hypotheses based on extant plants that tiny embryos and seed dormancy are basic for angiosperms as a whole. The minute size of the fossil embryos, and the modest nutrient storage tissues dictated by the overall small seed size, is also consistent with the interpretation that many early angiosperms were opportunistic, early successional colonizers of disturbance-prone habitats.

Effects of male and female sex steroids on the development of normal and the transient Froriep's dorsal root ganglia of the chick embryo.

PubMed

Liu, Jiali; Chen, Dawei; Goldstein, Ronald S; Cui, Sheng

2005-03-22

Sex steroids can influence developmental processes and support the survival of neurons in the embryonic central nervous system. Recent studies have shown that estrogen receptors are also expressed in the peripheral nervous system, in the dorsal root ganglia (DRG) of chick embryos. However, no studies have examined the effects of sex steroids on development of embryonic DRG. In the present study, 0.2 microg, 1.0 microg, 5.0 microg 10 microg, 20 microg, 25 microg, and 40 microg doses of testosterone or estradiol were delivered to chick embryos at Hamburger and Hamilton stage 18 (E3). The actions of these doses of sex steroids on the development of the C5DRG (fifth cervical ganglion, a "normal" DRG) and C2DRG (a transient ganglion known as a "Froriep's DRG") were then evaluated by quantifying ganglionic volumes, cell number, proliferation, and apoptosis after 1 day of growth to stage 23. We found that both testosterone and estradiol promoted proliferation of cells in both normal DRG and the Froriep's ganglia. By contrast, estradiol significantly increased the number of apoptotic cells, while testosterone strongly inhibited apoptosis. These actions of sex steroids on DRG development were dose-dependent, and C5DRG and C2DRG showed different sensitivities to the applied sex steroids. In addition, the present results demonstrated that specific ER and AR inhibitors (tamoxifen and flutamide) did not influence the effects of 5 microg E2 and 5 microg T on C2 and C5DRG significantly. These results demonstrate that male and female sex steroids can modulate DRG development through an epigenetic mechanism, as had been shown for the central nervous system.

Chronology of early embryonic development and embryo uterine migration in alpacas.

PubMed

Picha, Y; Tibary, A; Memon, M; Kasimanickam, R; Sumar, J

2013-03-01

The objectives were to: (1) describe the chronology of early embryonic development from ovulation to entry into the uterus; and (2) to determine the timing of embryo migration to the left uterine horn when ovulation occurred from the right ovary. The experiment was conducted in Peru. Females (n = 132) were randomly assigned to 15 experimental groups. All females were mated to an intact male, given 50 μg GnRH im (Cystorelin) and ovulation time determined by transrectal ultrasonography, conducted every 6 hours, starting 24 hours postmating. Animals were slaughtered at a specific intervals postovulation and reproductive tracts were recovered and subjected to oviductal and uterine flushing for females slaughtered between 1 and 6 days postovulation (dpo; Day 0 = ovulation) and uterine flushing for females slaughtered from 7 to 15 dpo for recovery of oocytes/embryos. Season of mating did not influence the interval from mating to ovulation (winter: 29 ± 6 hours vs. summer: 30 ± 6 hours; P = 0.49). Ovulation rates for females mated during winter and summer were 92% versus 100%, respectively (P = 0.05). Fertilization rates for winter and summer mated females were 72% and 82% (P = 0.29). Unfertilized ova were not retained in the uterine tube. All embryos collected were in the uterine tube ipsilateral to the side of ovulation between 1 and 5 dpo. Embryos reached the uterus on 6 dpo. Embryos began to elongate on 9 dpo; at this time, 83% of embryos derived from right-ovary ovulations were collected from the left uterine horn. Embryos occupied the entire uterine cavity by 10 dpo. In conclusion, we characterized early embryo development and location of embryo during its early developmental stages in alpaca. This was apparently the first report regarding chronology of embryo development and migration to the left horn in alpaca which merits further investigation regarding its role in maternal recognition of pregnancy. Copyright © 2013 Elsevier Inc. All rights reserved.

Use of the Coelomic Grafting Technique for Prolonged ex utero Cultivation of Late Preprimitive Streak-Stage Rabbit Embryos.

PubMed

Püschel, Bernd; Männer, Jörg

2016-01-01

Due to its morphological similarity with the early human embryo, the pregastrulation-stage rabbit may represent an appropriate mammalian model for studying processes involved in early human development. The usability of mammalian embryos for experimental studies depends on the availability of whole embryo culture methods facilitating prolonged ex utero development. While currently used culture methods yield high success rates for embryos from primitive streak stages onward, the success rate of extended cultivation of preprimitive streak-stage mammalian embryos is low for all previously established methods and for all studied species. This limits the usability of preprimitive streak-stage rabbit embryos in experimental embryology. We have tested whether the extraembryonic coelom of 4-day-old chick embryos may be used for prolonged ex utero culture of preprimitive streak-stage rabbit embryos (stage 2, 6.2 days post coitum). We found that, within this environment, stage 2 rabbit blastocysts can be cultured at decreasing success rates (55% after 1 day, 35% after 2 days, 15% after 3 days) up to a maximum of 72 h. Grafted blastocysts can continue development from the onset of gastrulation to early organogenesis and thereby form all structures characterizing age-matched controls (e.g. neural tube, somites, beating heart). Compared to normal controls, successfully cultured embryos developed at a slower rate and finally showed some structural and gross morphological anomalies. The method presented here was originally developed for whole embryo culture of mouse embryos by Gluecksohn-Schoenheimer in 1941. It is a simple and inexpensive method that may represent a useful extension to presently available ex utero culture systems for rabbit embryos. © 2016 S. Karger AG, Basel.

Bidirectional Fusion of the Heart-forming Fields in the Developing Chick Embryo

PubMed Central

Moreno-Rodriguez, R.A.; Krug, E.L.; Reyes, L.; Villavicencio, L.; Mjaatvedt, C.H.; Markwald, R.R.

2007-01-01

It is generally thought that the early pre-tubular chick heart is formed by fusion of the anterior or cephalic limits of the paired cardiogenic fields. However, this study shows that the heart fields initially fuse at their midpoint to form a transitory “butterfly”-shaped, cardiogenic structure. Fusion then progresses bi-directionally along the longitudinal axis in both cranial and caudal directions. Using in vivo labeling, we demonstrate that cells along the ventral fusion line are highly motile, crossing future primitive segments. We found that mesoderm cells migrated cephalically from the unfused tips of the anterior/cephalic wings into the head mesenchyme in the region that has been called the secondary heart field. Perturbing the anterior/cranial fusion results in formation of a biconal heart. A theoretical role of the ventral fusion line acting as a “heart organizer” and its role in cardia bifida is discussed. PMID:16252277

Method for Dissecting the Auditory Epithelium (Basilar Papilla) in Developing Chick Embryos.

PubMed

Levic, Snezana; Yamoah, Ebenezer N

2016-01-01

Chickens are an invaluable model for exploring auditory physiology. Similar to humans, the chicken inner ear is morphologically and functionally close to maturity at the time of hatching. In contrast, chicks can regenerate hearing, an ability lost in all mammals, including humans. The extensive morphological, physiological, behavioral, and pharmacological data available, regarding normal development in the chicken auditory system, has driven the progress of the field. The basilar papilla is an attractive model system to study the developmental mechanisms of hearing. Here, we describe the dissection technique for isolating the basilar papilla in developing chick inner ear. We also provide detailed examples of physiological (patch clamping) experiments using this preparation.

From soil mechanics to chick development.

PubMed

Wolpert, Lewis

2018-01-01

Here, I provide some recollections of my life, starting as a civil engineer in South Africa and how I gradually became interested in biology, particularly pattern formation. In retrospect, I think that my decision to work on chick embryos to study limb development back in 1966 turned out to be the right one. The principles discovered in these 50 years, both by my collaborators and by other colleagues, have established the principles of how the limb develops in higher vertebrates, including humans.

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.

MiRNA-mediated regulation of cell signaling and homeostasis in the early mouse embryo.

PubMed

Pernaute, Barbara; Spruce, Thomas; Rodriguez, Tristan A; Manzanares, Miguel

2011-02-15

At the time of implantation the mouse embryo is composed of three tissues the epiblast, trophectoderm and primitive endoderm. As development progresses the epiblast goes on to form the foetus whilst the trophectoderm and primitive endoderm give rise to extra-embryonic structures with important roles in embryo patterning and nutrition. Dramatic changes in gene expression occur during early embryo development and these require regulation at different levels. miRNAs are small non coding RNAs that have emerged over the last decade as important post-transcriptional repressors of gene expression. The roles played by miRNAs during early mammalian development are only starting to be elucidated. In order to gain insight into the function of miRNAs in the different lineages of the early mouse embryo we have analysed in depth the phenotype of embryos and extra-embryonic stem cells mutant for the miRNA maturation protein Dicer. This study revealed that miRNAs are involved in regulating cell signaling and homeostasis in the early embryo. Specifically, we identified a role for miRNAs in regulating the Erk signaling pathway in the extra-embryonic endoderm, cell cycle progression in extra-embryonic tissues and apoptosis in the epiblast.

Efficient and Rapid Isolation of Early-stage Embryos from Arabidopsis thaliana Seeds

PubMed Central

Raissig, Michael T.; Gagliardini, Valeria; Jaenisch, Johan; Grossniklaus, Ueli; Baroux, Célia

2013-01-01

In flowering plants, the embryo develops within a nourishing tissue - the endosperm - surrounded by the maternal seed integuments (or seed coat). As a consequence, the isolation of plant embryos at early stages (1 cell to globular stage) is technically challenging due to their relative inaccessibility. Efficient manual dissection at early stages is strongly impaired by the small size of young Arabidopsis seeds and the adhesiveness of the embryo to the surrounding tissues. Here, we describe a method that allows the efficient isolation of young Arabidopsis embryos, yielding up to 40 embryos in 1 hr to 4 hr, depending on the downstream application. Embryos are released into isolation buffer by slightly crushing 250-750 seeds with a plastic pestle in an Eppendorf tube. A glass microcapillary attached to either a standard laboratory pipette (via a rubber tube) or a hydraulically controlled microinjector is used to collect embryos from droplets placed on a multi-well slide on an inverted light microscope. The technical skills required are simple and easily transferable, and the basic setup does not require costly equipment. Collected embryos are suitable for a variety of downstream applications such as RT-PCR, RNA sequencing, DNA methylation analyses, fluorescence in situ hybridization (FISH), immunostaining, and reporter gene assays. PMID:23770918

Evolution of antero‐posterior patterning of the limb: Insights from the chick

PubMed Central

2017-01-01

Summary The developing limbs of chicken embryos have served as pioneering models for understanding pattern formation for over a century. The ease with which chick wing and leg buds can be experimentally manipulated, while the embryo is still in the egg, has resulted in the discovery of important developmental organisers, and subsequently, the signals that they produce. Sonic hedgehog (Shh) is produced by mesenchyme cells of the polarizing region at the posterior margin of the limb bud and specifies positional values across the antero‐posterior axis (the axis running from the thumb to the little finger). Detailed experimental embryology has revealed the fundamental parameters required to specify antero‐posterior positional values in response to Shh signaling in chick wing and leg buds. In this review, the evolution of the avian wing and leg will be discussed in the broad context of tetrapod paleontology, and more specifically, ancestral theropod dinosaur paleontology. How the parameters that dictate antero‐posterior patterning could have been modulated to produce the avian wing and leg digit patterns will be considered. Finally, broader speculations will be made regarding what the antero‐posterior patterning of chick limbs can tell us about the evolution of other digit patterns, including those that were found in the limbs of the earliest tetrapods. PMID:28734068

The effects of early post-hatching changes of imprinting object on the pattern of monocular/unihemispheric sleep of domestic chicks.

PubMed

Bobbo, Daniela; Vallortigara, Giorgio; Mascetti, Gian Gastone

2006-06-03

The pattern of monocular/unihemispheric sleep (Mo-Un sleep) was studied behaviourally in male and female chicks after early post-hatching changes of the imprinting object. Chicks were reared with an imprinting object on day 1 post-hatching which was removed or changed on day 2. On day 1, time spent in binocular sleep (both eyes closed) was similar in male and female chicks, though the number of episodes was lower in females than in males. There was no eye-closure bias in the pattern of Mo-Un sleep (one eye shut and the other open) in chicks of both sexes. On day 2, chicks subjected to the removal of imprinting object showed less time and number of episodes of binocular sleep than control chicks and chicks subjected to changes of imprinting object. There was no eye-closure bias in control chicks whilst a significant bias for more right Mo-Un sleep was recorded in chicks after removal and changes of imprinting object of both sexes. It is suggested that the removal or changes of imprinting object would cause a decrease of binocular sleep and trigger processes associated to secondary imprinting involving the left hemisphere. The bias for more right Mo-Un sleep (right eye-closure) could be the by-product of consolidation processes of secondary imprinting memories in the left hemisphere and/or of more left eye-opening as a result of periodical awakening of right hemisphere to control the environment after a stressful condition such as the removal or change of imprinting object.

Production of somatic chimera chicks by injection of bone marrow cells into recipient blastoderms.

PubMed

Heo, Young Tae; Lee, Sung Ho; Kim, Teoan; Kim, Nam Hyung; Lee, Hoon Taek

2012-01-01

Several types of cells, including blastoderm cells, primordial germ cells, and embryonic germ cells were injected into early-stage recipient embryos to produce chimera avians and to gain insights into cell development. However, a limited number of studies of avian adult stem cells have also been conducted. This study is, to the best of our knowledge, the first to evaluate chicken bone marrow cells' (chBMC) ability to differentiate into multiple cell lineages and capability to generate chimera chicks. We induced random differentiation of chBMCs in vitro and injected immunologically selected pluripotent cells in chBMCs into the blastoderms of recipient eggs. The multipotency of BMCs from the barred Plymouth rock (BPR) was confirmed via AP staining, RT-PCR, immunocytochemistry, and FACS using specific markers, such as Oct-4 and SSEA-1, 3 and 4. Isolated chBMCs were found to be able to induce in vitro differentiation to multiple cell lineages. Approximately 5,000 chBMCs were injected into the blastoderms of white leghorn (WL) recipients and proved able to contribute to the generation of somatic chimera chicks with a frequency of 2.7% (2 of 73). Confirmation of chimerism in hatched chicks was achieved via PCR analysis using D-loop-specific primers of BPR and WL. Our study demonstrated the successful production of chimera chicks using chBMC. Therefore, we propose that the use of adult chBMCs may constitute a new possible approach to the production of chimera poultry, and may provide helpful studies in avian developmental biology.

Effect of zinc imprinting and replacing inorganic zinc with organic zinc on early performance of broiler chicks.

PubMed

Mwangi, S; Timmons, J; Ao, T; Paul, M; Macalintal, L; Pescatore, A; Cantor, A; Ford, M; Dawson, K A

2017-04-01

The goal of this study was to determine the effects of feeding a zinc (Zn) deficient diet to broiler chicks for 96 h post-hatch followed by feeding diets with different Zn sources and supplemental levels (5 to 21 d) on the growth performance, tissue, and excreta Zn content. At the start of the study, four hundred 20-day-old male broiler chicks were divided into two groups. One group was fed a corn soybean meal based diet containing 25 mg of Zn/kg (imprinting diet, ID). The second group was fed the basal diet supplemented with 40 mg of Zn/kg from Zn oxide (ZnO) (non-imprinting diet, NID). Both groups were fed these diets for 96 h. At d 5, chicks from each group were randomly assigned to the dietary treatments consisting of the basal diet alone or the basal diet supplemented with 8 or 40 mg/kg Zn as ZnO or Zn proteinate. Main effects of post-hatch Zn ID were observed on feed intake and G:F. ID decreased (P < 0.05) feed intake and improved (P < 0.05) the gain to feed ratio (G:F) of 14 and 21 d old chicks compared to G:F of chicks fed NID. Additionally, G:F for 14 and 21 d was improved (P < 0.05) by interaction of Zn source × level. Furthermore, at d 21 chicks fed the ID had a lower (P < 0.05) Zn content in the tibia ash and excreta, and a higher (P < 0.05) Zn content in the pancreas tissue compared to chicks fed NID. These results suggest that Zn imprinting can affect body Zn stores and early performance. © The Author 2016. Published by Oxford University Press on behalf of Poultry Science Association.

Effect of zinc imprinting and replacing inorganic zinc with organic zinc on early performance of broiler chicks

PubMed Central

Timmons, J.; Ao, T.; Paul, M.; Macalintal, L.; Pescatore, A.; Cantor, A.; Ford, M.; Dawson, K. A.

2017-01-01

Abstract The goal of this study was to determine the effects of feeding a zinc (Zn) deficient diet to broiler chicks for 96 h post-hatch followed by feeding diets with different Zn sources and supplemental levels (5 to 21 d) on the growth performance, tissue, and excreta Zn content. At the start of the study, four hundred 20-day-old male broiler chicks were divided into two groups. One group was fed a corn soybean meal based diet containing 25 mg of Zn/kg (imprinting diet, ID). The second group was fed the basal diet supplemented with 40 mg of Zn/kg from Zn oxide (ZnO) (non-imprinting diet, NID). Both groups were fed these diets for 96 h. At d 5, chicks from each group were randomly assigned to the dietary treatments consisting of the basal diet alone or the basal diet supplemented with 8 or 40 mg/kg Zn as ZnO or Zn proteinate. Main effects of post-hatch Zn ID were observed on feed intake and G:F. ID decreased (P < 0.05) feed intake and improved (P < 0.05) the gain to feed ratio (G:F) of 14 and 21 d old chicks compared to G:F of chicks fed NID. Additionally, G:F for 14 and 21 d was improved (P < 0.05) by interaction of Zn source × level. Furthermore, at d 21 chicks fed the ID had a lower (P < 0.05) Zn content in the tibia ash and excreta, and a higher (P < 0.05) Zn content in the pancreas tissue compared to chicks fed NID. These results suggest that Zn imprinting can affect body Zn stores and early performance. PMID:27664197

Maternal dietary manganese protects chick embryos against maternal heat stress via epigenetic-activated antioxidant and anti-apoptotic abilities.

PubMed

Zhu, Yongwen; Lu, Lin; Liao, Xiudong; Li, Wenxiang; Zhang, Liyang; Ji, Cheng; Lin, Xi; Liu, Hsiao-Ching; Odle, Jack; Luo, Xugang

2017-10-27

Maternal heat stress induced the aberrant epigenetic patterns resulting in the abnormal development of offspring embryos. It is unclear whether maternal dietary manganese supplementation as an epigenetic modifier could protect the chick embryonic development against maternal heat stress via epigenetic mechanisms. To test this hypothesis using an avian model, a completely randomized design with a 2 (maternal normal and high environmental temperatures of 21 and 32°C, respectively) × 3 (maternal dietary manganese sources, the control diet without manganese supplementation and the control diet + 120 mg/kg as either inorganic or organic manganese) factorial arrangement was adopted. Maternal environmental hyperthermia increased mRNA expressions of heat shock proteins 90 and 70, cyclin-dependent kinase 6 and B-cell CLL/lymphoma 2-associated X protein displaying oxidative damage and apoptosis in the embryonic heart. Maternal environmental hyperthermia impaired the embryonic development associated with the alteration of epigenetic status, as evidenced by global DNA hypomethylation and histone 3 lysine 9 hypoacetylation in the embryonic heart. Maternal dietary manganese supplementation increased the heart anti-apoptotic gene B-cell CLL/lymphoma 2 expressions under maternal environmental hyperthermia and manganese superoxide dismutase enzyme activity in the embryonic heart. Maternal dietary organic Mn supplementation effectively eliminated the impairment of maternal environmental hyperthermia on the embryonic development. Maternal dietary manganese supplementation up-regulated manganese superoxide dismutase mRNA expression by reducing DNA methylation and increasing histone 3 lysine 9 acetylation of its promoter. It is suggested that maternal dietary manganese addition could protect the chick embryonic development against maternal heat stress via enhancing epigenetic-activated antioxidant and anti-apoptotic abilities.

The chronic infusion of nicotine into the developing chick embryo does not alter the density of (-)-[3H]nicotine-binding sites or vestibular function

NASA Technical Reports Server (NTRS)

Roll, R. L.; Jones, T. A.; Benowitz, N. L.; Morley, B. J.

1993-01-01

(-)-Nicotine (1.2 mg/day) or saline was infused into chick embryos (Gallus domesticus) for 10 days beginning 12 h beyond the eight day of incubation (E8 + 12 h). Twelve h beyond the eighteenth day of incubation (E18 + 12 h), the eggs were opened to access the embryos and subcutaneous skull electrodes placed. Short latency vestibular response thresholds and input/output functions were determined to assess neurophysiological consequences of chronic nicotine administration. Samples of serum and extraembryonic (amniotic and albumen) fluid were analyzed by gas chromatography-mass spectrometry to determine the levels of nicotine and its major metabolite, cotinine. The brains were removed and divided into diencephalon and mesencephalon and the density of (-)-[3H]nicotine binding sites in each brain area was measured. Nicotine and cotinine were found in the serum and extraembryonic fluid, but nicotinic receptors were not up-regulated in the brains of animals infused with nicotine in comparison to controls. Vestibular response thresholds also did not differ between nicotine-treated and control animals.

Early Activation of MAPK and Apoptosis in Nutritive Embryos of Calyptraeid Gastropods.

PubMed

Lesoway, Maryna P; Collin, Rachel; Abouheif, Ehab

2017-07-01

Investigation of alternative phenotypes, different morphologies produced by a single genome, has contributed novel insights into development and evolution. Yet, the mechanisms underlying developmental switch points between alternative phenotypes remain poorly understood. The calyptraeid snails Crepidula navicella and Calyptraea lichen produce two phenotypes: viable and nutritive embryos, where nutritive embryos arrest their development after gastrulation and are ingested by their viable siblings as a form of intracapsular nutrition. Here, we investigate the activity of mitogen-activated protein kinase (MAPK, ERK1/2) and apoptosis during early cleavage. MAPK and apoptosis, found in a previous transcriptomic study, are known to be involved in organization of other spiralian embryos and nutritive embryo development, respectively. In the model Crepidula fornicata, MAPK activation begins at the 16-cell stage. In contrast, we discovered in C. navicella and C. lichen that many embryos begin MAPK activation at the one-cell stage. A subset of embryos shows a similar pattern of MAPK activation to C. fornicata at later stages. In all stages where MAPK is detected, the activation pattern is highly variable, frequently occurring in all quadrants or in multiple tiers of cells. We also detected apoptosis in cleaving embryos, while C. fornicata and Crepidula lessoni, which do not produce nutritive embryos, show no signs of apoptosis during cleavage. Our results show that MAPK and apoptosis are expressed during early development in species with nutritive embryos, and raises the possibility that these processes may play a role and even interact with one another in producing the nutritive embryo phenotype. © 2017 Wiley Periodicals, Inc.

Cannabinoid receptor 1 signaling in embryo neurodevelopment

PubMed Central

Psychoyos, Delphine; Vinod, K. Yaragudri; Cao, Jin; Hyson, Richard L.; Wlodarczyk, Bogdan; He, Weimin; Cooper, Thomas B.; Hungund, Basalingappa L.; Finnell, Richard H.

2014-01-01

In utero exposure to THC, the psychoactive component of marijuana, is associated with an increased risk for neurodevelopmental defects in the offspring by interfering with the functioning of the endocannabinoid (eCB) system. At the present time it is not clearly known whether the eCB system is present prior to neurogenesis. Using an array of biochemical techniques we analyzed the levels of CB1 receptors, eCBs (AEA and 2-AG), and the enzymes (NAPE-PLD, DAGLα, DAGLβ MAGL and FAAH) involved in the metabolism of the eCBs in chick and mouse models during development. The findings demonstrate the presence of eCB system in early embryo, prior to neurogenesis. The eCB system might play a critical role in early embryogenesis and there might be adverse developmental consequences of in utero exposure to marijuana and other drugs of abuse during this period. PMID:22311661

Hippocampus and medial striatum dissociation during goal navigation by geometry or features in the domestic chick: An immediate early gene study.

PubMed

Mayer, Uwe; Pecchia, Tommaso; Bingman, Verner Peter; Flore, Michele; Vallortigara, Giorgio

2016-01-01

We employed a standard reference memory task to study the involvement of the hippocampal formation (HF) of domestic chicks that used the boundary geometry of a test environment to orient to and locate a reward. Using the immediate early gene product c-Fos as a neuronal activity marker, we found enhanced HF activation in chicks that learned to locate rewarded corners using the shape of a rectangular arena compared to chicks trained to solve the task by discriminating local features in a square-shaped arena. We also analyzed neuronal activity in the medial part of the medial striatum (mMSt). Surprisingly, in mMSt we observed a reverse pattern, with higher activity in the chicks that were trained to locate the goal by local features. Our results identify two seemingly parallel, memory systems in chicks, with HF central to the processing of spatial-geometrical information and mMSt important in supporting local feature discrimination. © 2015 Wiley Periodicals, Inc.

Differential muscular myosin heavy chain expression of the pectoral and pelvic girdles during early growth in the king penguin (Aptenodytes patagonicus) chick.

PubMed

Erbrech, Aude; Robin, Jean-Patrice; Guérin, Nathalie; Groscolas, René; Gilbert, Caroline; Martrette, Jean-Marc

2011-06-01

Continuous growth, associated with a steady parental food supply, is a general pattern in offspring development. So that young chicks can acquire their locomotor independence, this period is usually marked by a fast maturation of muscles, during which different myosin heavy chain (MyHC) isoforms are expressed. However, parental food provisioning may fluctuate seasonally, and offspring therefore face a challenge to ensure the necessary maturation of their tissues when energy is limited. To address this trade-off we investigated muscle maturation in both the pectoral and pelvic girdles of king penguin chicks. This species has an exceptionally long rearing period (1 year), which is prolonged when parental food provisioning is drastically reduced during the sub-Antarctic winter. Approximately 1 month post hatching, chicks acquire a functional pedestrian locomotion, which uses pelvic muscles, whereas swimming, which uses the pectoral muscles, only occurs 1 year later. We therefore tested the hypothesis that the MyHC content of the leg muscles reaches a mature state before those of the pectoral muscles. We found that leg muscle MyHC composition changed with the progressive acquisition of pedestrian locomotion, whereas pectoral muscle fibres reached their mature MyHC profile as early as hatching. Contrary to our predictions, the acquisition of the adult profile in pectoral muscles could be related to an early maturation of the contractile muscular proteins, presumably associated with early thermoregulatory capacities of chicks, necessary for survival in their cold environment. This differential maturation appears to reconcile both the locomotor and environmental constraints of king penguin chicks during growth.

Characterization of a photoproduct of 7,12-dimethylbenz[alpha]anthracene and its effects on chick-embryo cells in culture.

PubMed Central

Warshawsky, D; Kerns, E; Bissell, M J; Calvin, M

1977-01-01

A common impurity of 7,12-dimethylbenz[alpha]anthracene was more effective than 7,12-dimethylbenz[alpha]anthracene in inducing morphological alterations, and in causing an increase in glucose uptake, DNA synthesis and cell number in chick-embryo fibroblasts. Gradual morphological transformation follows the increase in DNA synthesis after 2 days when either primary or secondary cultures are treated with 3 microgram of the compound/ml. The compound, isolated from 7,12-dimethylbenz[alpha]anthracene by alumina column chromatography, was characterized by t.l.c., mass spectroscopy, carbon-hydrogen analysis, u.v. and nuclear-magnetic-resonance spectroscopy and thermal decomposition. It was the photo-oxidation product of 7,12-dimethylbenz[alpha]anthracene, 7,12-epidioxy-7,12-dimethylbenz[alpha]anthracene. It is suggested that some of the biological effects observed after treatment of cultures with 7,12-dimethylbenz[alpha]anthracene may be due in part to the presence of the photo-oxidation product. PMID:407902

Low dose trichloroethylene alters cytochrome P450 - 2C subfamily expression in the developing chick heart

PubMed Central

Makwana, Om; Ahles, Lauren; Lencinas, Alejandro; Selmin, Ornella I.; Runyan, Raymond B.

2013-01-01

Trichloroethylene (TCE) is an organic solvent and common environmental contaminant. TCE exposure is associated with heart defects in humans and animal models. Primary metabolism of TCE in adult rodent models is by specific hepatic cytochrome P450 enzymes (Lash et al., 2000). As association of TCE exposure with cardiac defects is in exposed embryos prior to normal liver development, we investigated metabolism of TCE in the early embryo. Developing chick embryos were dosed in ovo with environmentally relevant doses of TCE (8 ppb and 800 ppb) and RNA was extracted from cardiac and extra-cardiac tissue (whole embryo without heart). Real time PCR showed upregulation of CYP2H1 transcripts in response to TCE exposure in the heart. No detectable cytochrome expression was found in extra-cardiac tissue. As seen previously, the dose response was non-monotonic and 8ppb elicited stronger upregulation than 800 ppb. Immunostaining for CYP2C subfamily expression confirmed protein expression and showed localization in both myocardium and endothelium. TCE exposure increased protein expression in both tissues. These data demonstrate that the earliest embryonic expression of phase I detoxification enzymes is in the developing heart. Expression of these CYPs is likely to be relevant to the susceptibility of the developing heart to environmental teratogens. PMID:22855351

Effect of a photoperiodic green light programme during incubation on embryo development and hatch process.

PubMed

Tong, Q; McGonnell, I M; Demmers, T G M; Roulston, N; Bergoug, H; Romanini, C E; Verhelst, R; Guinebretière, M; Eterradossi, N; Berckmans, D; Exadaktylos, V

2018-04-01

This study was conducted to evaluate the effect of a 12-h light, 12-h dark (12L : 12D) photoperiod of green light during day 1 to day 18 of incubation time, on embryo growth, hormone concentration and the hatch process. In the test group, monochromatic light was provided by a total of 204 green light-emitting diodes (522 nm) mounted in a frame which was placed above the top tray of eggs to give even spread of illumination. No light-dark cycle was used in the control group. Four batches of eggs (n=300/group per batch) from fertile Ross 308 broiler breeders were used in this experiment. The beak length and crown-rump length of embryos incubated under green light were significantly longer than that of control embryos at day 10 and day 12, respectively (P<0.01). Furthermore, green light-exposed embryos had a longer third toe length compared with control embryos at day 10, day 14 and day 17 (P=0.02). At group level (n=4 batches), light stimulation had no effect on chick weight and quality at take-off, the initiation of hatch and hatch window. However, the individual hatching time of the light exposure focal chicks (n=33) was 3.4 h earlier (P=0.49) than the control focal chicks (n=36) probably due to the change in melatonin rhythm of the light group. The results of this study indicate that green light accelerates embryo development and alters hatch-related hormones (thyroid and corticosterone), which may result in earlier hatching.

Embryo density and medium volume effects on early murine embryo development.

PubMed

Canseco, R S; Sparks, A E; Pearson, R E; Gwazdauskas, F C

1992-10-01

One-cell mouse embryos were used to determine the effects of drop size and number of embryos per drop for optimum development in vitro. Embryos were collected from immature C57BL6 female mice superovulated with pregnant mare serum gonadotropin and human chorionic gonadotropin and mated by CD1 males. Groups of 1, 5, 10, or 20 embryos were cultured in 5-, 10-, 20-, or 40-microliters drops of CZB under silicon oil at 37.5 degrees C in a humidified atmosphere of 5% CO2 and 95% air. Development score for embryos cultured in 10 microliters was higher than that of embryos cultured in 20 or 40 microliters. Embryos cultured in groups of 5, 10, or 20 had higher development scores than embryos cultured singly. The highest development score was obtained by the combination of 5 embryos per 10-microliters drop. The percentage of live embryos in 20 or 40 microliters was lower than that of embryos cultured in 10 microliters. Additionally, the percentage of live embryos cultured singly was lower than that of embryos cultured in groups. Our results suggest that a stimulatory interaction occurs among embryos possibly exerted through the secretion of growth factors. This effect can be diluted if the embryos are cultured in large drops or singly.

Laminarin improves developmental competence of porcine early stage embryos by inhibiting oxidative stress.

PubMed

Jiang, Hao; Liang, Shuang; Yao, Xue-Rui; Jin, Yong-Xun; Shen, Xing-Hui; Yuan, Bao; Zhang, Jia-Bao; Kim, Nam-Hyung

2018-04-23

Laminarin (LMA), a β-glucan mixture with good biocompatibility, improves the growth performance and immune response when used as food additives and nutraceuticals. The aim of the present research was to explore the effects of LMA on porcine early stage embryo development, as well as the underlying mechanisms. The results showed that the developmental competence of porcine early stage embryos was dramatically improved after LMA supplementation during the in vitro culture period. The presence of 20 μg/mL LMA during the in vitro culture period significantly improved cleavage rate, blastocyst formation rates, hatching rate, and total cell number in the blastocyst compared to that in the control group. Notably, LMA attenuated the intracellular reactive oxygen species generation induced by H 2 O 2 . Furthermore, LMA not only increased intracellular glutathione levels, but also ameliorated mitochondrial membrane potential. In addition, the expression of a zygotic genome activation related gene (YAP1), pluripotency-related genes (OCT4, NANOG, and SOX2), and hatching-related genes (COX2, GATA4, and ITGA5) were up-regulated following LMA supplementation during porcine early stage embryo development. These results demonstrate that LMA has beneficial effects on the development of porcine early stage embryos via regulation of oxidative stress. This evidence provides a novel method for embryo development improvement associated with exposure to LMA. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of early environmental enrichment upon open-field behavior and timidity in the domestic chick.

PubMed

Jones, R B

1982-03-01

Early environmental enrichment was evaluated by its effect on the behavior of 7-day-old male and female domestic chicks in an open field or novel environment and in a hole-in-the-wall test of timidity. The chicks were housed in same-sex groups of 10. The bare environments contained wood litter, food, and water, whereas the enriched boxes also contained various objects. In the open field, immobility was lower while feeding, walking, jumping and vocalization were higher in the enriched birds than in those reared in the bare environment. Enrichment also decreased emergence latencies in the hole-in-the-wall box. The increased stimulation provided by environmental enrichment may decrease fearfulness in subsequent fear-inducing situations and may enhance the ability of animals to adapt to novelty.

Effects of prenatal exposure to antithyroid drugs on imprinting behavior in chicks.

PubMed

Kagami, Keisuke; Nishigori, Hidekazu; Nishigori, Hideo

2010-09-01

Thyroid hormones play important roles in vertebrate brain development. However, there is little understanding of the direct effects of fetal thyroid dysfunction, i.e., not acquired through the mother, on learning ability. In the present study, we use a chick embryo as a fetal model to investigate the effects of prenatal exposure to antithyroid drugs on imprinting behavior in hatched chicks. Methimazole (MMI) at 20micromol/egg or 5micromol/egg of propylthiouracil (PTU) was administered to eggs on day 14 while the control was given only a vehicle. An imprinting test was conducted after the chicks hatched. Day-old chicks were exposed to a rotating training object for 150min. The next day, the trained chicks were exposed to the training object and a novel object. The imprinting preference was represented as a preference score (PS) calculated as the rate of following the training object to following the training and novel objects. In the MMI-treated chicks, the PS was 0.68+/-0.06 (range, 0.38-0.88), which was significantly lower than that in the control chicks (0.86+/-0.04, p<0.01). In the PTU-treated chicks, the PS was 0.69+/-0.04 (range, 0.52-0.89), which was also significantly lower than that in the control (0.88+/-0.02, p<0.001). The present findings suggested that fetal thyroid dysfunction inhibited brain development, leading to impaired learning and memory. Our chick model can be considered useful for investigating the direct effects of prenatal exposure to antithyroid drugs or substances in the environment on learning ability after birth. Copyright 2010 Elsevier Inc. All rights reserved.

The avian embryo responding to microgravity of space flight

NASA Technical Reports Server (NTRS)

Hullinger, Ronald L.

1993-01-01

Of all the many potential and real microenvironmental influences, only gravity would appear to have remained relatively constant and ubiquitous for developing organisms. Histo- and organogenesis as well as differential growth of the embryo and fetus may have evolved with a constant environmental factor of gravity. Chick embryos of 2-day and 9-day stages of incubation were flown in an incubator on the Space Shuttle during a 9-day mission. Significant differences in embryo response to this microgravity environment were observed. This paper offers an analysis and suggests mechanisms which may contribute to these results.

Expression of voltage-activated calcium channels in the early zebrafish embryo.

PubMed

Sanhueza, Dayán; Montoya, Andro; Sierralta, Jimena; Kukuljan, Manuel

2009-05-01

Increases in cytosolic calcium concentrations regulate many cellular processes, including aspects of early development. Calcium release from intracellular stores and calcium entry through non-voltage-gated channels account for signalling in non-excitable cells, whereas voltage-gated calcium channels (CaV) are important in excitable cells. We report the expression of multiple transcripts of CaV, identified by its homology to other species, in the early embryo of the zebrafish, Danio rerio, at stages prior to the differentiation of excitable cells. CaV mRNAs and proteins were detected as early as the 2-cell stages, which indicate that they arise from both maternal and zygotic transcription. Exposure of embryos to pharmacological blockers of CaV does not perturb early development significantly, although late effects are appreciable. These results suggest that CaV may have a role in calcium homeostasis and control of cellular process during early embryonic development.

Metabolic and mitochondrial dysfunction in early mouse embryos following maternal dietary protein intervention.

PubMed

Mitchell, Megan; Schulz, Samantha L; Armstrong, David T; Lane, Michelle

2009-04-01

Dietary supply of nutrients, both periconception and during pregnancy, influence the growth and development of the fetus and offspring and their health into adult life. Despite the importance of research efforts surrounding the developmental origins of health and disease hypothesis, the biological mechanisms involved remain elusive. Mitochondria are of major importance in the oocyte and early embryo, particularly as a source of ATP generation, and perturbations in their function have been related to reduced embryo quality. The present study examined embryo development following periconception exposure of females to a high-protein diet (HPD) or a low-protein diet (LPD) relative to a medium-protein diet (MPD; control), and we hypothesized that perturbed mitochondrial metabolism in the mouse embryo may be responsible for the impaired embryo and fetal development reported by others. Although the rate of development to the blastocyst stage did not differ between diets, both the HPD and LPD reduced the number of inner cell mass cells in the blastocyst-stage embryo. Furthermore, mitochondrial membrane potential was reduced and mitochondrial calcium levels increased in the 2-cell embryo. Embryos from HPD females had elevated levels of reactive oxygen species and ADP concentrations, indicative of metabolic stress and, potentially, the uncoupling of oxidative phosphorylation, whereas embryos from LPD females had reduced mitochondrial clustering around the nucleus, suggestive of an overall quietening of metabolism. Thus, although periconception dietary supply of different levels of protein is permissive of development, mitochondrial metabolism is altered in the early embryo, and the nature of the perturbation differs between HPD and LPD exposure.

SDOCT Doppler velocimetry for investigating the morphological influences on blood flow in the developing chick embryo heart

NASA Astrophysics Data System (ADS)

Davis, Anjul M.; Rothenberg, Florence G.; Law, Tzuo H.; Taber, Larry A.; Izatt, Joseph A.

2007-02-01

The onset of congenital heart disease (CHD) is believed to occur at very early stages of development. Investigations in the initiation and development of CHD has been hampered by the inability to image early stage heart structure and function, in vivo. Imaging small animals using optical coherence tomography (OCT) has filled a niche between the limited penetration depth of confocal microscopy and insufficient resolution from ultrasound. Previous demonstrations of chick heart imaging using OCT have entailed excision of, or arresting the heart to prevent motion artifacts. In this summary, we introduce SDOCT Doppler velocimetry as an enhancement of Doppler OCT for in vivo measurement of localized temporal blood flow dynamics. With this technique, dynamic velocity waveforms were measured in the outflow tract of the heart tube. These flow dynamics correlate to a finite element model of pulsatile flow and may lead to a further understanding of morphological influences on early heart development.

Sensitivity of early mouse embryos to (/sup 3/H)thymidine

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

Spindle, A.; Wu, K.; Pedersen, R.A.

1982-12-01

Effects of intranuclear radiation on the developmental capacity of early mouse embryos were studied by exposing embryos to (/sup 3/H)thymidine and counting the number of embryos forming blastocysts, trophoblast outgrowths, inner cell masses (ICMs), and two-layer ICMs (differentiated into primary endoderm and ectoderm). When embryos were cultured from the 2-cell stage for 8 days in the continuous presence of (/sup 3/H)thymidine, concentrations as low as 0.2 nCi/ml reduced the number of embryos forming two-layer ICMs. At 1 nCi/ml, the number of both ICMs and two-layer ICMs were reduced, and at 10 nCi/ml the number of embryos developing to all threemore » post-blastocyst endpoints was reduced. Blastocyst formation was not affected even at the highst concentration (/sup 3/H)thymidine and then cultured further in unlabelled medium, the effects were similar to those of 8-day exposure. When embryos were exposed to (/sup 3/H)thymidine for 24 h at various developmental stages, effects were less severe than when they were exposed continuously for 3 or 8 days, and the sensitivity of embryos differed between stages. The 24-h exposure of immunosurgically isolated ICMS to (/sup 3/H)thymidine revealed that the high sensitivity of the ICM to (/sup 3/H)thymidine persists through the late blastocyst stage and declines progressively thereafter. Autoradiography indicated that the change in radiosensitivity of embryos or ICMs is generally related to their ability to incorporate (/sup 3/H)thymidine into the DNA.« less

Detailed analysis of the δ-crystallin mRNA-expressing region in early development of the chick pituitary gland.

PubMed

Inoue, Makiko; Shiina, Tomoya; Aizawa, Sayaka; Sakata, Ichiro; Takagi, Hiroyasu; Sakai, Takafumi

2012-06-01

Although δ-crystallin (δ-crys), also known as lens protein, is transiently expressed in Rathke's pouch (RP) of the chick embryo, detailed temporal and spatial expression patterns have been obscure. In this study, to understand the relationship between the δ-crys mRNA-expressing region and RP formation, we examined the embryonic expression pattern of δ-crys mRNA in the primordium of the adenohypophysis. δ-crys mRNA expression was initially found at stage 15 anterior to the foregut and posterior to the invaginated oral ectoderm. After RP formation, the δ-crys mRNA was expressed in the post-ventral region of RP and the anterior region of RP. δ-crys mRNA expression was then restricted to the cephalic lobe of the pituitary gland. From stage 20, the δ-crys and alpha-glycoprotein subunit (αGSU) mRNA-expressing regions were almost completely overlapping. The αGSU mRNA-expressing region is thought to be the primordium of the pars tuberalis, and these regions were overlapped with the Lhx3 mRNA-expressing region. The intensity of δ-crys mRNA expression gradually decreased with development and completely disappeared by stage 34. These results suggest that the embryonic chick pituitary gland consists of two different regions labeled with δ-crys and Lhx3.

DYZ1 copy number variation, Y chromosome polymorphism and early recurrent spontaneous abortion/early embryo growth arrest.

PubMed

Yan, Junhao; Fan, Lingling; Zhao, Yueran; You, Li; Wang, Laicheng; Zhao, Han; Li, Yuan; Chen, Zi-Jiang

2011-12-01

To find the association between recurrent spontaneous abortion (RSA)/early embryo growth arrest and Y chromosome polymorphism. Peripheral blood samples of the male patients of big Y chromosome, small Y chromosome and other male patients whose partners suffered from unexplained RSA/early embryo growth arrest were collected. PCR and real-time fluorescent quantitative PCR were used to test the deletion and the copy number variation of DYZ1 region in Y chromosome of the patients. A total of 79 big Y chromosome patients (48 of whose partners suffered from RSA or early embryo growth arrest), 7 small Y chromosome patients, 106 other male patients whose partners had suffered from unexplained RSA or early embryo growth arrest, and 100 normal male controls were enrolled. There was no fraction deletion of DYZ1 detected both in big Y patients and in normal men. Of RSA patients, 1 case showed deletion of 266bp from the gene locus 25-290bp, and 2 cases showed deletion of 773bp from 1347 to 2119bp. Of only 7 small Y chromosome patients, 2 cases showed deletion of 266bp from 25 to 290bp, and 4 cases showed deletion of 773bp from 1347 to 2119bp and 275bp from 3128 to 3420bp. The mean of DYZ1 copies was 3900 in normal control men; the mean in big Y patients was 5571, in RSA patients was 2655, and in small Y patients was 1059. All of the others were significantly different (P<0.01) compared with normal control men, which meant that DYZ1 copy number in normal control men was less than that of big Y chromosome patients, and was more than that of unexplained early RSA patients and small Y patients. The integrity and copy number variation of DYZ1 are closely related to the Y chromosome length under microscope. The cause of RSA/early embryo growth arrest in some couples may be the increase (big Y patients) or decrease of DYZ1 copy number in the husbands' Y chromosome. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Antibodies induced by vaccination with purified chick embryo cell culture vaccine (PCECV) cross-neutralize non-classical bat lyssavirus strains.

PubMed

Malerczyk, Claudius; Selhorst, Thomas; Tordo, Noël; Moore, Susan; Müller, Thomas

2009-08-27

Tissue-culture vaccines like purified chick embryo cell vaccine (PCECV) have been shown to provide protection against classical rabies virus (RABV) via pre-exposure or post-exposure prophylaxis. A cross-neutralization study was conducted using a panel of 100 human sera, to determine, to what extent after vaccination with PCECV protection exists against non-classical bat lyssavirus strains like European bat lyssavirus (EBLV) type 1 and 2 and Australian bat lyssavirus (ABLV). Virus neutralizing antibody (VNA) concentrations against the rabies virus variants CVS-11, ABLV, EBLV-1 and EBLV-2 were determined by using a modified rapid fluorescent focus inhibition test. For ABLV and EBLV-2, the comparison to CVS-11 revealed almost identical results (100% adequate VNA concentrations >or=0.5 IU/mL; correlation coefficient r(2)=0.69 and 0.77, respectively), while for EBLV-1 more scattering was observed (97% adequate VNA concentrations; r(2)=0.50). In conclusion, vaccination with PCECV produces adequate VNA concentrations against classical RABV as well as non-classical lyssavirus strains ABLV, EBLV-1, and EBLV-2.

The influence of early embryo traits on human embryonic stem cell derivation efficiency.

PubMed

O'Leary, Thomas; Heindryckx, Björn; Lierman, Sylvie; Van der Jeught, Margot; Menten, Björn; Deforce, Dieter; Cornelissen, Ria; de Sousa Lopes, Susana Chuva; De Sutter, Petra

2011-05-01

Despite its prognostic value in in vitro fertilization, early embryo morphology is not reported on in the derivation of human embryonic stem cell (hESC) lines. Standard hESC derivation does rely on blastocyst development and its efficiency is highly correlated to inner cell mass (ICM) quality. Poor-quality embryos (PQEs) donated for hESC derivation may have a range of cleavage-stage abnormalities that are known to compromise further development. This study was implemented to determine whether specific PQEs traits influence the efficiency of good-quality ICMs to derive new hESC lines. We found that although the types of PQEs investigated were all able to make blastocysts with good-quality ICMs, the ICMs were unequal in their ability to derive hESCs. Good-quality ICMs from embryos with multiple poor-quality traits were unable to generate hESC lines, in contrast to good-quality ICMs from embryos with a single poor-quality trait. In addition, our data suggest a direct correlation between the number of ICM cells present in the blastocyst and its capacity to derive new hESC lines. This study is the first to demonstrate that ICM quality alone is an incomplete indicator of hESC derivation and that application of in vitro fertilization-based early embryo scoring can help predict hESC derivation efficiency. Experiments aiming to quantify, improve upon, or compare hESC derivation efficiency should thus take into consideration early embryo morphology scoring for the comparison of groups with equal developmental competence.

Precision matters for position decoding in the early fly embryo

NASA Astrophysics Data System (ADS)

Petkova, Mariela D.; Tkacik, Gasper; Wieschaus, Eric F.; Bialek, William; Gregor, Thomas

Genetic networks can determine cell fates in multicellular organisms with precision that often reaches the physical limits of the system. However, it is unclear how the organism uses this precision and whether it has biological content. Here we address this question in the developing fly embryo, in which a genetic network of patterning genes reaches 1% precision in positioning cells along the embryo axis. The network consists of three interconnected layers: an input layer of maternal gradients, a processing layer of gap genes, and an output layer of pair-rule genes with seven-striped patterns. From measurements of gap gene protein expression in hundreds of wild-type embryos we construct a ``decoder'', which is a look-up table that determines cellular positions from the concentration means, variances and co-variances. When we apply the decoder to measurements in mutant embryos lacking various combinations of the maternal inputs, we predict quantitative changes in the output layer such as missing, altered or displaced stripes. We confirm these predictions by measuring pair-rule expression in the mutant embryos. Our results thereby show that the precision of the patterning network is biologically meaningful and a necessary feature for decoding cell positions in the early fly embryo.

Immunologic effects of low levels of ochratoxin A in ovo: utilization of a chicken embryo model.

PubMed

Harvey, R B; Kubena, L F; Naqi, S A; Gyimah, J E; Corrier, D E; Panigrahy, B; Phillips, T D

1987-01-01

Ochratoxin A (OA) was administered to 13-day-old chicken embryos via the chorioallantoic membrane. The 7-day LD50 value (day 20 incubation) of OA was calculated at 7.9 micrograms of OA. Ochratoxin-treated embryos (2.5 micrograms) had slight but significant changes in numbers of immunoglobulin-bearing cells in the bursa but not in the spleen. Chicks hatched from in ovo-treated eggs were challenged with 9 X 10(4) colony-forming units (CFU) of beta-hemolytic Escherichia coli (O1:K1) at 7 days of age via the thoracic air sac. Lesion scores of OA-treated chicks were equal to or less severe than those of controls. Hatchmates of the above chicks were vaccinated with a homologous killed E. coli bacterin (O1:K1) at both 2 and 4 weeks of age and challenged with 10(4) CFU of E. coli at 7 weeks. Post-challenge lesions were present in three vaccinated untreated controls and no OA-treated chicks. We conclude that although in ovo exposure to OA may marginally suppress immunoglobulin-bearing cells of bursa, chicks hatched from OA-treated eggs respond as well as controls to an antigen and resist infection by a virulent organism.

Distinct spatiotemporal expression of ISM1 during mouse and chick development.

PubMed

Osório, Liliana; Wu, Xuewei; Zhou, Zhongjun

2014-01-01

Isthmin 1 (ISM1) constitutes the founder of a new family of secreted proteins characterized by the presence of 2 functional domains: thrombospondin type 1 repeat (TSR1) and adhesion-associated domain in MUC4 and other proteins (AMOP). ISM1 was identified in the frog embryo as a member of the FGF8 synexpression group due to its expression in the brain midbrain-hindbrain boundary (MHB) or isthmus. In zebrafish, ISM1 was described as a WNT- and NODAL-regulated gene. The function of ISM1 remains largely elusive. So far, ISM1 has been described as an angiogenesis inhibitor that has a dual function in endothelial cell survival and cell death. For a better understanding of ISM1 function, we examined its spatiotemporal distribution in mouse and chick using RT-PCR, ISH, and IHC analyses. In the mouse, ISM1 transcripts are found in tissues such as the anterior mesendoderm, paraxial and lateral plate mesoderm, MHB and trunk neural tube, as well as in the somites and dermomyotome. In the newborn and adult, ISM1 is prominently expressed in the lung and brain. In addition to its putative role during embryonic and postnatal development, ISM1 may also be important for organ homeostasis in the adult. In the chick embryo, ISM1 transcripts are strongly detected in the ear, eye, and spinal cord primordia. Remarkable differences in ISM1 spatiotemporal expression were found during mouse and chick development, despite the high homology of ISM1 orthologs in these species.

Distinct spatiotemporal expression of ISM1 during mouse and chick development

PubMed Central

Osório, Liliana; Wu, Xuewei; Zhou, Zhongjun

2014-01-01

Isthmin 1 (ISM1) constitutes the founder of a new family of secreted proteins characterized by the presence of 2 functional domains: thrombospondin type 1 repeat (TSR1) and adhesion-associated domain in MUC4 and other proteins (AMOP). ISM1 was identified in the frog embryo as a member of the FGF8 synexpression group due to its expression in the brain midbrain–hindbrain boundary (MHB) or isthmus. In zebrafish, ISM1 was described as a WNT- and NODAL-regulated gene. The function of ISM1 remains largely elusive. So far, ISM1 has been described as an angiogenesis inhibitor that has a dual function in endothelial cell survival and cell death. For a better understanding of ISM1 function, we examined its spatiotemporal distribution in mouse and chick using RT-PCR, ISH, and IHC analyses. In the mouse, ISM1 transcripts are found in tissues such as the anterior mesendoderm, paraxial and lateral plate mesoderm, MHB and trunk neural tube, as well as in the somites and dermomyotome. In the newborn and adult, ISM1 is prominently expressed in the lung and brain. In addition to its putative role during embryonic and postnatal development, ISM1 may also be important for organ homeostasis in the adult. In the chick embryo, ISM1 transcripts are strongly detected in the ear, eye, and spinal cord primordia. Remarkable differences in ISM1 spatiotemporal expression were found during mouse and chick development, despite the high homology of ISM1 orthologs in these species. PMID:24675886

Mitotic wavefronts mediated by mechanical signaling in early Drosophila embryos

NASA Astrophysics Data System (ADS)

Kang, Louis; Idema, Timon; Liu, Andrea; Lubensky, Tom

2013-03-01

Mitosis in the early Drosophila embryo demonstrates spatial and temporal correlations in the form of wavefronts that travel across the embryo in each cell cycle. This coordinated phenomenon requires a signaling mechanism, which we suggest is mechanical in origin. We have constructed a theoretical model that supports nonlinear wavefront propagation in a mechanically-excitable medium. Previously, we have shown that this model captures quantitatively the wavefront speed as it varies with cell cycle number, for reasonable values of the elastic moduli and damping coefficient of the medium. Now we show that our model also captures the displacements of cell nuclei in the embryo in response to the traveling wavefront. This new result further supports that mechanical signaling may play an important role in mediating mitotic wavefronts.

Expression profiling of the mouse early embryo: Reflections and Perspectives

PubMed Central

Ko, Minoru S. H.

2008-01-01

Laboratory mouse plays important role in our understanding of early mammalian development and provides invaluable model for human early embryos, which are difficult to study for ethical and technical reasons. Comprehensive collection of cDNA clones, their sequences, and complete genome sequence information, which have been accumulated over last two decades, have provided even more advantages to mouse models. Here the progress in global gene expression profiling in early mouse embryos and, to some extent, stem cells are reviewed and the future directions and challenges are discussed. The discussions include the restatement of global gene expression profiles as snapshot of cellular status, and subsequent distinction between the differentiation state and physiological state of the cells. The discussions then extend to the biological problems that can be addressed only through global expression profiling, which include: bird’s-eye view of global gene expression changes, molecular index for developmental potency, cell lineage trajectory, microarray-guided cell manipulation, and the possibility of delineating gene regulatory cascades and networks. PMID:16739220

Calcium-sensing receptor (CASR) is involved in porcine in vitro fertilisation and early embryo development.

PubMed

Liu, C; Liu, Y; Larsen, K; Hou, Y P; Callesen, H

2018-01-01

It has been demonstrated that extracellular calcium is necessary in fertilisation and embryo development but the mechanism is still not well understood. The present study mainly focussed on the extracellular calcium effector called the calcium-sensing receptor (CASR) and examined its expression in porcine gametes and embryos and its function during fertilisation and early embryo development. By using reverse transcription polymerase chain reaction, CASR was found to be expressed in porcine oocytes, spermatozoa and embryos at different developmental stages. Functionally, medium supplementation with a CASR agonist or an antagonist during in vitro fertilisation (IVF) and in vitro culture (IVC) was tested. During fertilisation, the presence of a CASR agonist increased sperm penetration rate and decreased polyspermy rate leading to an increased normal fertilisation rate. During embryo development, for the IVF embryos, agonist treatment during IVC significantly increased cleavage rate and blastocyst formation rate compared with the control group. Furthermore, parthenogenetically activated embryos showed similar results with lower cleavage and blastocyst formation rates in the antagonist group than in the other groups. It was concluded that CASR, as the effector of extracellular calcium, modulates porcine fertilisation and early embryo development.

Somitic disruption of GNAS in chick embryos mimics progressive osseous heteroplasia

PubMed Central

Cairns, Dana M.; Pignolo, Robert J.; Uchimura, Tomoya; Brennan, Tracy A.; Lindborg, Carter M.; Xu, Meiqi; Kaplan, Frederick S.; Shore, Eileen M.; Zeng, Li

2013-01-01

Progressive osseous heteroplasia (POH) is a rare developmental disorder of heterotopic ossification (HO) caused by heterozygous inactivating germline mutations in the paternal allele of the GNAS gene. Interestingly, POH lesions have a bewildering mosaic distribution. Using clinical, radiographic, and photographic documentation, we found that most of the 12 individuals studied had a lesional bias toward one side or the other, even showing exclusive sidedness. Most strikingly, all had a dermomyotomal distribution of HO lesions. We hypothesized that somatic mutations in a progenitor cell of somitic origin may act on a background of germline haploinsufficiency to cause loss of heterozygosity at the GNAS locus and lead to the unilateral distribution of POH lesions. Taking advantage of the chick system, we examined our hypothesis by mimicking loss of heterozygosity of GNAS expression using dominant-negative GNAS that was introduced into a subset of chick somites, the progenitors that give rise to dermis and muscle. We observed rapid ectopic cartilage and bone induction at the axial and lateral positions in a unilateral distribution corresponding to the injected somites, which suggests that blocking GNAS activity in a targeted population of progenitor cells can lead to mosaic ectopic ossification reminiscent of that seen in POH. PMID:23863715

Neural retina of chick embryo in organ culture: effects of blockade of growth factors by suramin.

PubMed

Cirillo, A; Chifflet, S; Villar, B

2001-06-01

The neural retina is a highly organized organ whose final histoarchitecture depends on the presence of diverse growth factors and on their interactions with extracellular matrix components. However, the role of growth factors on retinal development is not fully understood. Suramin has been shown to produce diverse cellular effects via the simultaneous block of the action of several growth factors. We have therefore studied the effects of suramin on organotypic culture of chick embryo neural retina in order to gain further insights into the participation of growth factors in neural retinal development. Neural retina was incubated for 24 h with suramin at 50-200 microM and then processed to determine cell proliferation, nuclear morphology, and actin distribution. Suramin provoked extensive morphological changes revealed by a decrease in BrdU incorporation, alterations in cellular organization, and disruption of the outer limiting membrane, with the emergence of cellular elements through it. All of these effects were dose-dependent and markedly attenuated by the simultaneous presence of suramin and fibroblast growth factor 2 (FGF-2) in the culture medium. These findings indicate that suramin induces pleiotropic effects on the histoarchitecture of the chicken neural retina in organ culture and suggest that FGF-2 is one of the biological modulators involved in the maintenance of the structural organization of the chicken neural retina.

Application of high-performance liquid chromatography to the determination of glyoxylate synthesis in chick embryo liver.

PubMed

Qureshi, A A; Elson, C E; Lebeck, L A

1982-11-19

The isolation and identification of three major alpha-keto end products (glyoxylate, pyruvate, alpha-ketoglutarate) of the isocitrate lyase reaction in 18-day chick embryo liver have been described. This was accomplished by the separation of these alpha-keto acids as their 2,4-dinitrophenylhydrazones (DNPHs) by high-performance liquid chromatography (HPLC). The DNPHs of alpha-keto acids were eluted with an isocratic solvent system of methanol-water-acetic acid (60:38.5:1.5) containing 5 mM tetrabutylammonium phosphate from a reversed-phase ultrasphere C18 (IP) and from a radial compression C18 column. The separation can be completed on the radial compression column within 15-20 min as compared to 30-40 min with a conventional reversed-phase column. Retention times and peak areas were integrated for both the assay samples and reference compounds. A relative measure of alpha-keto acid in the peak was calculated by comparison with the standard. The identification of each peak was done on the basis of retention time matching, co-chromatography with authentic compounds, and stopped flow UV-VIS scanning between 240 and 440 nm. Glyoxylate represented 5% of the total product of the isocitrate lyase reaction. Day 18 parallels the peak period of embryonic hepatic glycogenesis which occurs at a time when the original egg glucose reserve has been depleted.

Gene Transfer to Chicks Using Lentiviral Vectors Administered via the Embryonic Chorioallantoic Membrane

PubMed Central

Hen, Gideon; Yosefi, Sara; Shinder, Dmitry; Or, Adi; Mygdal, Sivan; Condiotti, Reba; Galun, Eithan; Bor, Amir; Sela-Donenfeld, Dalit; Friedman-Einat, Miriam

2012-01-01

The lack of affordable techniques for gene transfer in birds has inhibited the advancement of molecular studies in avian species. Here we demonstrate a new approach for introducing genes into chicken somatic tissues by administration of a lentiviral vector, derived from the feline immunodeficiency virus (FIV), into the chorioallantoic membrane (CAM) of chick embryos on embryonic day 11. The FIV-derived vectors carried yellow fluorescent protein (YFP) or recombinant alpha-melanocyte-stimulating hormone (α-MSH) genes, driven by the cytomegalovirus (CMV) promoter. Transgene expression, detected in chicks 2 days after hatch by quantitative real-time PCR, was mostly observed in the liver and spleen. Lower expression levels were also detected in the brain, kidney, heart and breast muscle. Immunofluorescence and flow cytometry analyses confirmed transgene expression in chick tissues at the protein level, demonstrating a transduction efficiency of ∼0.46% of liver cells. Integration of the viral vector into the chicken genome was demonstrated using genomic repetitive (CR1)-PCR amplification. Viability and stability of the transduced cells was confirmed using terminal deoxynucleotidyl transferase (dUTP) nick end labeling (TUNEL) assay, immunostaining with anti-proliferating cell nuclear antigen (anti-PCNA), and detection of transgene expression 51 days post transduction. Our approach led to only 9% drop in hatching efficiency compared to non-injected embryos, and all of the hatched chicks expressed the transgenes. We suggest that the transduction efficiency of FIV vectors combined with the accessibility of the CAM vasculature as a delivery route comprise a new powerful and practical approach for gene delivery into somatic tissues of chickens. Most relevant is the efficient transduction of the liver, which specializes in the production and secretion of proteins, thereby providing an optimal target for prolonged study of secreted hormones and peptides. PMID:22606269

Optimized ex-ovo culturing of chick embryos to advanced stages of development.

PubMed

Cloney, Kellie; Franz-Odendaal, Tamara Anne

2015-01-24

Research in anatomy, embryology, and developmental biology has largely relied on the use of model organisms. In order to study development in live embryos model organisms, such as the chicken, are often used. The chicken is an excellent model organism due to its low cost and minimal maintenance, however they present observational challenges because they are enclosed in an opaque eggshell. In order to properly view the embryo as it develops, the shell must be windowed or removed. Both windowing and ex ovo techniques have been developed to assist researchers in the study of embryonic development. However, each of the methods has limitations and challenges. Here, we present a simple, optimized ex ovo culture technique for chicken embryos that enables the observation of embryonic development from stage HH 19 into late stages of development (HH 40), when many organs have developed. This technique is easy to adopt in both undergraduate classes and more advanced research laboratories where embryo manipulations are conducted.

Monitoring the hatch time of individual chicken embryos.

PubMed

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

2013-02-01

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

The early-stage diagnosis of albinic embryos by applying optical coherence tomography

NASA Astrophysics Data System (ADS)

Yang, Bor-Wen; Wang, Shih-Yuan; Wang, Yu-Yen; Cai, Jyun-Jhang; Chang, Chung-Hao

2013-09-01

Albinism is a kind of congenital disease of abnormal metabolism. Poecilia reticulata (guppy fish) is chosen as the model to study the development of albinic embryos as it is albinic, ovoviviparous and with short life period. This study proposed an imaging method for penetrative embryo investigation using optical coherence tomography. By imaging through guppy mother’s reproduction purse, we found the embryo’s eyes were the early-developed albinism features. As human’s ocular albinism typically appear at about four weeks old, it is the time to determine if an embryo will grow into an albino.

A multicenter prospective study to assess the effect of early cleavage on embryo quality, implantation, and live-birth rate.

PubMed

de los Santos, Maria José; Arroyo, Gemma; Busquet, Ana; Calderón, Gloria; Cuadros, Jorge; Hurtado de Mendoza, Maria Victoria; Moragas, Marta; Herrer, Raquel; Ortiz, Agueda; Pons, Carme; Ten, Jorge; Vilches, Miguel Angel; Figueroa, Maria José

2014-04-01

To investigate the impact of early cleavage (EC) on embryo quality, implantation, and live-birth rates. Prospective cross-sectional study. Multicenter study. Seven hundred embryo transfers and 1,028 early-stage human embryos. None. Implantation according to the presence of EC and embryo quality. The presence of EC is associated with embryo quality, especially in cycles with autologous oocytes. However, the use of EC as an additional criterion for selecting an embryo for transfer does not appear to significantly improve likelihood of implantation. Furthermore, embryos that presented EC had live-birth rates per implanted embryo similar to those that did not show any sign of cleavage. At least for conventional embryo culture and morphologic evaluations, the additional evaluation of EC in embryos may not be valuable to improve embryo implantation. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

The culture of chick embryo mesoderm cells in hydrated collagen gels.

PubMed

Sanders, E J; Prasad, S

1983-04-01

Chick embryo mesoderm cells are various stages of differentiation were cultured in three-dimensional matrices of hydrated collagen. The tissues used were: stage 5 mesoderm from regions adjacent to the primitive streak; stage 12 mesoderm, comprising somitic, unsegmented (segmental plate) and lateral plate mesoderm; and stage 18 sclerotome. Explants were examined by phase contrast microscopy, including time-lapse, and scanning and transmission electron microscopy. The cells showed an increased ability to adhere to, and move in, the collagen gel with advancing stage. Of the stage 12 tissues, the unsegmented mesoderm was initially the slowest to grow out of the explant. Sclerotome cells showed by far the greatest ability to move within the gel. Where the collagen fibrils were randomly oriented, the cell morphology was polypodial and advancing lamellipodia showed clear undulations at their leading edges. A distinction was drawn between these undulations and the classical major ruffles which are seen in two-dimensional culture to uplift and pass back along the cell surface. The latter were not seen in the collagen matrix and were presumably suppressed by the three-dimensional culture configuration while the leading edge undulations were not. Ultrastructural examination showed that the cells possessed patches of amorphous material on their surface, which was sometimes interposed between the plasma membrane and collagen fibrils. Addition of hyaluronic acid (2 mg/ml) had an effect only the segmented mesoderm, where outgrowth was enhanced. Although the addition of plasma fibronectin (50 micrograms/ml) to the cultures did not affect any of the tissues, the removal of this substance, by antifibronectin antiserum or by the use of fibronectin depleted serum, inhibited outgrowth in most cases. The only tissue not reproducibly inhibited in this way was sclerotome. Alignment of the collagen fibres by the explants was observed, accompanied by an elongation of the outgrowing cells

A model system for testing gene vectors using murine tumor cells on the chorioallantoic membrane of the chick embryo.

PubMed

Dani, Sergio U; Espindola, Rachel

2002-06-30

We developed a model system for testing gene vectors, based on the growth of murine tumors on the chorioallantoic membrane (CAM) of embryonic chickens. The ability of selected murine cells to grow on the CAM was rated according to the following criteria: i) formation of tumor masses; ii) metastasis formation; iii) reproducibility; iv) yield, indicated as the number of embryos surviving to assessment time with visible tumors on the CAM; v) maintainability of the cell, both in the original host and the embryonic chick, or 'shuttle maintainability'; vi) detection by the naked eye, and vii) cost/benefit relation. The murine melanoma cell lineage, B16F10, which efficiently forms distinct, pigmented tumor masses and metastases on the CAM, performed better in this model than the murine B61 cell line. In vitro transduction of B16F10 cells with a recombinant adenovirus carrying a construct of the E. coli LacZ gene followed by inoculation onto the CAM resulted in beta-galactosidase expression in the tumor mass growing on the CAM. This model is potentially applicable to preclinical evaluation of gene vectors, especially for gene therapy of cancer.

Effect of exogenous transforming growth factor β1 (TGF-β1) on early bovine embryo development.

PubMed

Barrera, Antonio D; García, Elina V; Miceli, Dora C

2018-06-08

SummaryDuring preimplantation development, embryos are exposed and have the capacity to respond to different growth factors present in the maternal environment. Among these factors, transforming growth factor β1 (TGF-β1) is a well known modulator of embryonic growth and development. However, its action during the first stages of development, when the embryo transits through the oviduct, has not been yet elucidated. The objective of the present study was to examine the effect of early exposure to exogenous TGF-β1 on embryo development and expression of pluripotency (OCT4, NANOG) and DNA methylation (DNMT1, DNMT3A, DNMT3B) genes in bovine embryos produced in vitro. First, gene expression analysis of TGF-β receptors confirmed a stage-specific expression pattern, showing greater mRNA abundance of TGFBR1 and TGFBR2 from the 2- to the 8-cell stage, before embryonic genome activation. Second, embryo culture for the first 48 h in serum-free CR1aa medium supplemented with 50 or 100 ng/ml recombinant TGF-β1 did not affect the cleavage and blastocyst rate (days 7 and 8). However, RT-qPCR analysis showed a significant increase in the relative abundance of NANOG and DNMT3A in the 8-cell stage embryos and expanded blastocysts (day 8) derived from TGF-β1 treated embryos. These results suggest an early action of exogenous TGF-β1 on the bovine embryo, highlighting the importance to provide a more comprehensive understanding of the role of TGF-β signalling during early embryogenesis.

Hemodynamic flow visualization of early embryonic great vessels using μPIV.

PubMed

Goktas, Selda; Chen, Chia-Yuan; Kowalski, William J; Pekkan, Kerem

2015-01-01

Microparticle image velocimetry (μPIV) is an evolving quantitative methodology to closely and accurately monitor the cardiac flow dynamics and mechanotransduction during vascular morphogenesis. While PIV technique has a long history, contemporary developments in advanced microscopy have significantly expanded its power. This chapter includes three new methods for μPIV acquisition in selected embryonic structures achieved through advanced optical imaging: (1) high-speed confocal scanning of transgenic zebrafish embryos, where the transgenic erythrocytes act as the tracing particles; (2) microinjection of artificial seeding particles in chick embryos visualized with stereomicroscopy; and (3) real-time, time-resolved optical coherence tomography acquisition of vitelline vessel flow profiles in chick embryos, tracking the erythrocytes.

[Studies of the eating behavior of Japanese quail chicks in the early postnatal period].

PubMed

Khekhneva, A V; Gur'eva, T S; Dadasheva, O A; Sychev, V N

2006-01-01

Time of the eating reaction (response to video signals) and eating behavior shortly after hatching were studied in Japanese quail chicks whose embryonic development took place under normal or changed gravity. Chicks partially incubated in a changed gravity showed a much slower eating reaction when compared with the chicks the prenatal development of which occurred under the normal gravity. In the chicks incubated at 1 g and placed in individual cages immediately after dominating afferentation for the eating behavior was visual Observations in the study will be used as a basis for designing a technology for handling and maintenance of hatchlings of the Japanese quail as a potential heterotrophic component of space life support systems.

Central cell-derived peptides regulate early embryo patterning in flowering plants.

PubMed

Costa, Liliana M; Marshall, Eleanor; Tesfaye, Mesfin; Silverstein, Kevin A T; Mori, Masashi; Umetsu, Yoshitaka; Otterbach, Sophie L; Papareddy, Ranjith; Dickinson, Hugh G; Boutiller, Kim; VandenBosch, Kathryn A; Ohki, Shinya; Gutierrez-Marcos, José F

2014-04-11

Plant embryogenesis initiates with the establishment of an apical-basal axis; however, the molecular mechanisms accompanying this early event remain unclear. Here, we show that a small cysteine-rich peptide family is required for formation of the zygotic basal cell lineage and proembryo patterning in Arabidopsis. EMBRYO SURROUNDING FACTOR 1 (ESF1) peptides accumulate before fertilization in central cell gametes and thereafter in embryo-surrounding endosperm cells. Biochemical and structural analyses revealed cleavage of ESF1 propeptides to form biologically active mature peptides. Further, these peptides act in a non-cell-autonomous manner and synergistically with the receptor-like kinase SHORT SUSPENSOR to promote suspensor elongation through the YODA mitogen-activated protein kinase pathway. Our findings demonstrate that the second female gamete and its sexually derived endosperm regulate early embryonic patterning in flowering plants.

Model of human recurrent respiratory papilloma on chicken embryo chorioallantoic membrane for tumor angiogenesis research.

PubMed

Uloza, Virgilijus; Kuzminienė, Alina; Palubinskienė, Jolita; Balnytė, Ingrida; Ulozienė, Ingrida; Valančiūtė, Angelija

2017-07-01

We aimed to develop a chick embryo chorioallantoic membrane (CAM) model of recurrent respiratory papilloma (RPP) and to evaluate its morphological and morphometric characteristics, together with angiogenic features. Fresh RRP tissue samples obtained from 13 patients were implanted in 174 chick embryo CAMs. Morphological, morphometric, and angiogenic changes in the CAM and chorionic epithelium were evaluated up until 7 days after the implantation. Immunohistochemical analysis (34βE12, Ki-67, MMP-9, PCNA, and Sambucus nigra staining) was performed to detect cytokeratins and endothelial cells and to evaluate proliferative capacity of the RRP before and after implantation on the CAM. The implanted RRP tissue samples survived on CAM in 73% of cases while retaining their essential morphologic characteristics and proliferative capacity of the original tumor. Implants induced thickening of both the CAM (241-560%, p=0.001) and the chorionic epithelium (107-151%, p=0.001), while the number of blood vessels (37-85%, p=0.001) in the CAM increased. The results of the present study confirmed that chick embryo CAM is a relevant host for serving as a medium for RRP fresh tissue implantation. The CAM assay demonstrated the specific RRP tumor growth pattern after implantation and provided the first morphological and morphometric characterization of the RRP CAM model that opens new horizons in studying this disease.

Early embryonic survival and embryo development in two lines of rabbits divergently selected for uterine capacity.

PubMed

Peiró, R; Santacreu, M A; Climent, A; Blasco, A

2007-07-01

The aim of this work is to study early embryo survival and development in 2 lines divergently selected for high and low uterine capacity throughout 10 generations. A total of 162 female rabbits from the high line and 133 from the low line were slaughtered at 25, 48, or 62 h of gestation. There were no differences in ovulation rate and fertilization rate between lines in any of the 3 stages of gestation. Embryo survival, estimated as the number of normal embryos recovered at a constant ovulation rate, was similar in both lines at 25 and 48 h. Embryo survival was greater in the high line [D (posterior mean of the difference between the high and low lines) = 0.57 embryos] at 62 h of gestation. There was no difference in embryonic stage of development at 25 h, but at 48 and 62 h of gestation, the high line, compared with the low line, had a greater percentage of early morulae (83 vs. 72%) and compacted morulae (55 vs. 38%). Divergent selection for uterine capacity appeared to modify embryo development, at least from 48 h of gestation, and embryo survival from 62 h.

[Specification of cell destiny in early Caenorhabditis elegans embryo].

PubMed

Schierenberg, E

1997-02-01

Embryogenesis of the nematode Caenorhabditis elegans has been described completely on a cell-by-cell basis and found to be essentially invariant. With this knowledge in hands, micromanipulated embryos and mutants have been analyzed for cell lineage defects and the distribution of specific gene products. The results challenge the classical view of cell-autonomous development in nematodes and indicate that the early embryo of C. elegans is a highly dynamic system. A network of inductive events between neighboring cells is being revealed, which is necessary to assign different developmental programs to blastomeres. In those cases where molecules involved in these cell-cell interactions have been identified, homologies to cell surface receptors, ligands and transcription factors found in other systems have become obvious.

Rediscovering the chick embryo as a model to study retinal development

PubMed Central

2012-01-01

The embryonic chick occupies a privileged place among animal models used in developmental studies. Its rapid development and accessibility for visualization and experimental manipulation are just some of the characteristics that have made it a vertebrate model of choice for more than two millennia. Until a few years ago, the inability to perform genetic manipulations constituted a major drawback of this system. However, the completion of the chicken genome project and the development of techniques to manipulate gene expression have allowed this classic animal model to enter the molecular age. Such techniques, combined with the embryological manipulations that this system is well known for, provide a unique toolkit to study the genetic basis of neural development. A major advantage of these approaches is that they permit targeted gene misexpression with extremely high spatiotemporal resolution and over a large range of developmental stages, allowing functional analysis at a level, speed and ease that is difficult to achieve in other systems. This article provides a general overview of the chick as a developmental model focusing more specifically on its application to the study of eye development. Special emphasis is given to the state of the art of the techniques that have made gene gain- and loss-of-function studies in this model a reality. In addition, we discuss some methodological considerations derived from our own experience that we believe will be beneficial to researchers working with this system. PMID:22738172

Early bovine embryos regulate oviduct epithelial cell gene expression during in vitro co-culture.

PubMed

Schmaltz-Panneau, Barbara; Cordova, Amanda; Dhorne-Pollet, Sophie; Hennequet-Antier, Christelle; Uzbekova, Sveltlana; Martinot, Emmanuelle; Doret, Sarah; Martin, Patrice; Mermillod, Pascal; Locatelli, Yann

2014-10-01

In mammals, the oviduct may participate to the regulation of early embryo development. In vitro co-culture of early bovine embryos with bovine oviduct epithelial cells (BOEC) has been largely used to mimic the maternal environment. However, the mechanisms of BOEC action have not been clearly elucidated yet. The aim of this study was to determine the response of BOEC cultures to the presence of developing bovine embryos. A 21,581-element bovine oligonucleotide array was used compare the gene expression profiles of confluent BOEC cultured for 8 days with or without embryos. This study revealed 34 differentially expressed genes (DEG). Of these 34 genes, IFI6, ISG15, MX1, IFI27, IFI44, RSAD2, IFITM1, EPSTI1, USP18, IFIT5, and STAT1 expression increased to the greatest extent due to the presence of embryos with a major impact on antiviral and immune response. Among the mRNAs at least 25 are already described as induced by interferons. In addition, transcript levels of new candidate genes involved in the regulation of transcription, modulation of the maternal immune system and endometrial remodeling were found to be increased. We selected 7 genes and confirmed their differential expression by quantitative RT-PCR. The immunofluorescence imaging of cellular localization of STAT1 protein in BOEC showed a nuclear translocation in the presence of embryos, suggesting the activation of interferon signaling pathway. This first systematic study of BOEC transcriptome changes in response to the presence of embryos in cattle provides some evidences that these cells are able to adapt their transcriptomic profile in response to embryo signaling. Copyright © 2014 Elsevier B.V. All rights reserved.

Sildenafil citrate (Viagra) impairs fertilization and early embryo development in mice.

PubMed

Glenn, David R J; McClure, Neil; Cosby, S Louise; Stevenson, Michael; Lewis, Sheena E M

2009-03-01

To determine the effects of sildenafil citrate, a cyclic monophosphate-specific type 5 phosphodiesterase inhibitor known to affect sperm function, on fertilization and early embryo cleavage. This acute mammal study included male and female mice assigned randomly, the females sacrificed after mating and their oocytes/embryos evaluated at four time periods after treatment. Academic research environment. Male and female CBAB(6) mice. Female mice were injected intraperitoneally with 5 IU gonadotropin (hCG) to stimulate follicular growth and induce ovulation. They were each caged with a male that had been gavaged with sildenafil citrate (0.06 mg/0.05 mL) and allowed to mate. After 12, 36, 60, and 84 h, females were killed, their oviducts were dissected out, and retrieved embryos were assessed for blastomere number and quality. Fertilization rates and numbers of embryos were evaluated after treatment. Fertilization rates (day 1) were markedly reduced (-33%) in matings where the male had taken sildenafil citrate. Over days 2-4, the numbers of embryos developing in the treated group were significantly fewer than in the control group. There was also a trend for impaired cleavage rates within those embryos, although this did not reach significance. The impairments to fertility caused by sildenafil citrate have important implications for infertility centers and for couples who are using this drug precoitally while attempting to conceive.

Fluorescence histochemical and elec-ron microscopical observations on sympathetic ganglia of the chick embryo cultured with and without hydrocortisone.

PubMed

Hervonen, H; Eränkö, O

1975-01-01

Lumbar sympathetic ganglia of 12-day-old chick embryos were cultured in organ cultures for 14 days with 1, 10 or 100 mg/l of hydrocortisone or without it. Catecholamines were demonstrated by the formaldehyde-induced fluorescence method. For electron microscopy, the cultures were fixed with glutarialdehyde and osmium tetroxide. Two types of cells with catecholamine fluoresecence were observed in the control cultures: (1) weakly fluorescent sympathetic neurons and sympathicoblasts with long nerve fibres, which were the most common cell type in the explant, and (2) brightly fluorescent cells with or without fluorescent processes, which were less common and were scattered in the explant. Hydrocortisone caused a great increase in the number of the brightly fluorescent cells. With 10 mg/l of hydrocortisone the increase was about ten-fold as compared with the control cultures. There was no change in the morphology of the cells, nor could any change be observed in the fluorescence intensity by eye. Electron microscopically the mature neurons were the most common cell type on the surface of the culture, while more immature sympathicoblasts were seen in the deeper layers. Cells were also found which contained large numbers of catecholamine-strong granular vesicles 105-275 nm in diameter. These cells were infrequent. They had round vesicular nuclei and resembled also in other respects sympathicoblasts or young nerve cells. One such cell was found in mitotic division by electron microscopy. Hydrocortisone caused a marked increase in the number of these granule-containing cells and their processes. Cells which could have been classified as the small intensely fluorescent cells of the mammalian ganglion type or their electron microscopic equivalent, the granule-containing cells were found neither in the control cultures nor in the hydrocortisone-containing cultures. It is concluded that most brightly fluorescent cells in cultured sympathetic ganglia of the chick are nerve cells

Early embryo mortality in natural human reproduction: What the data say

PubMed Central

Jarvis, Gavin E.

2017-01-01

How many human embryos die between fertilisation and birth under natural conditions? It is widely accepted that natural human embryo mortality is high, particularly during the first weeks after fertilisation, with total prenatal losses of 70% and higher frequently claimed. However, the first external sign of pregnancy occurs two weeks after fertilisation with a missed menstrual period, and establishing the fate of embryos before this is challenging. Calculations are additionally hampered by a lack of data on the efficiency of fertilisation under natural conditions. Four distinct sources are used to justify quantitative claims regarding embryo loss: (i) a hypothesis published by Roberts & Lowe in The Lancet  is widely cited but has no practical quantitative value; (ii) life table analyses give consistent assessments of clinical pregnancy loss, but cannot illuminate losses at earlier stages of development; (iii) studies that measure human chorionic gonadotrophin (hCG) reveal losses in the second week of development and beyond, but not before; and (iv) the classic studies of Hertig and Rock offer the only direct insight into the fate of human embryos from fertilisation under natural conditions. Re-examination of Hertig’s data demonstrates that his estimates for fertilisation rate and early embryo loss are highly imprecise and casts doubt on the validity of his numerical analysis. A recent re-analysis of hCG study data concluded that approximately 40-60% of embryos may be lost between fertilisation and birth, although this will vary substantially between individual women. In conclusion, natural human embryo mortality is lower than often claimed and widely accepted. Estimates for total prenatal mortality of 70% or higher are exaggerated and not supported by the available data. PMID:28580126

Chorio-Allantoic Membrane Grafting of Chick Limb Buds as a Class Practical.

ERIC Educational Resources Information Center

McLachlan, John C.

1981-01-01

A new method of carrying out grafts of early embryonic chick limb buds to the chick chorio-allantoic membrane and a processing schedule which renders cartilage elements visible in whole mount are discussed, including implications for the procedures and their results. (Author/DC)

Comparison of nicotinic receptor binding and biotransformation of coniine in the rat and chick.

PubMed

Forsyth, C S; Speth, R C; Wecker, L; Galey, F D; Frank, A A

1996-12-31

Coniine, an alkaloid from Conium maculatum (poison hemlock), is a known teratogen in many domestic species with maternal ingestion resulting in arthrogryposis of the offspring. We have previously shown that rats are not susceptible and rabbits only weakly susceptible to coniine-induced arthrogryposis. However, the chick embryo does provide a reproducible laboratory animal model of coniine-induced teratogenesis. The reason for this cross-species variation is unknown. The purpose of this study was to evaluate coniine binding to nicotinic receptors and to measure coniine metabolism in vitro between susceptible and non-susceptible species. Using the chick model, neither the peripheral nicotinic receptor antagonist d-tubocurarine chloride nor the central nicotinic receptor antagonist trimethaphan camsylate blocked the teratogenesis or lethality of 1.5% coniine (50 microliters/egg). Trimethaphan camsylate enhanced coniine-induced lethality in a dose-dependent manner. Neither nicotinic receptor blocker prevented nicotine sulfate-induced malformations but d-tubocurarine chloride did block lethality in a dose-dependent manner. Competition by coniine for [125I]-alpha-bungarotoxin to nicotinic receptors isolated from adult rat diaphragm and chick thigh muscle and competition by coniine for [3H]-cytisine to receptors from rat and chick brain were used to assess coniine binding to nicotinic receptors. The IC50 for coniine in rat diaphragm was 314 microM while that for chick leg muscle was 70 microM. For neuronal nicotinic receptors, the IC50s of coniine for maternal rat brain, fetal rat brain, and chick brain were 1100 microM, 820 microM, and 270 microM, respectively. There were no differences in coniine biotransformation in vitro by microsomes from rat or chick livers. Differences in apparent affinity of coniine for nicotinic receptors or differences in the quantity of the nicotinic receptor between the rat and chick may explain, in part, the differences in susceptibility of

Effect of PMA-induced protein kinase C activation on development and apoptosis in early zebrafish embryos.

PubMed

Hrubik, Jelena; Glisic, Branka; Samardzija, Dragana; Stanic, Bojana; Pogrmic-Majkic, Kristina; Fa, Svetlana; Andric, Nebojsa

2016-12-01

Protein kinase C (PKC) isoforms have been implicated in several key steps during early development, but the consequences of xenobiotic-induced PKC activation during early embryogenesis are still unknown. In this study, zebrafish embryos were exposed to a range of phorbol 12-myristate 13-acetate (PMA) concentrations (0-200μg/L) at different time points after fertilization. Results showed that 200μgPMA/L caused development of yolk bags, cardiac edema, slow blood flow, pulsating blood flow, slow pulse, elongated heart, lack of tail fins, curved tail, and coagulation. PMA exposure decreased survival rate of the embryos starting within the first 24h and becoming more pronounced after prolonged exposure (96h). PMA increased the number of apoptotic cells in the brain region as demonstrated by acridine orange staining and caused up-regulation of caspase 9 (casp9) and p53 up-regulated modulator of apoptosis (puma) mRNA in whole embryos. PMA caused oxidative stress in the embryos as demonstrated by decreased mRNA expression of catalase and superoxide dismutase 2. Inhibition of Pkc with GF109203X improved overall survival rate, reduced apoptosis in the brain and decreased expression of casp9 and puma in the PMA-exposed embryos. However, Pkc inhibition neither prevented development of deformities nor reversed oxidative stress in the PMA-exposed embryos. These data suggest that direct over-activation of Pkc during early embryogenesis of zebrafish is associated with apoptosis and decreased survival rate of the embryos. Copyright © 2016 Elsevier Inc. All rights reserved.

HINTW, a W-chromosome HINT gene in chick, is expressed ubiquitously and is a robust female cell marker applicable in intraspecific chimera studies.

PubMed

Nagai, Hiroki; Sezaki, Maiko; Bertocchini, Federica; Fukuda, Kimiko; Sheng, Guojun

2014-05-01

Grafting and transplantation experiments in embryology require proper distinction between host and donor tissues. For the avian model this has traditionally been achieved by using two closely related species (e.g., chick and quail) followed by species-specific antibody staining. Here, we show that an in situ hybridization probe against the HINTW gene is a robust and reliable marker for female-derived chicken cells. At all pre-circulation stages tested, all cells in female embryos, independently confirmed by PCR analysis, were strongly positive for HINTW, whereas all male embryos were negative. This probe is broadly applicable in intra-specific chick/chick chimera studies, and as a proof of principle, we utilized this probe to detect female cells in three experimental settings: (1) to mark female donor cells in a node transplantation assay; (2) to distinguish female cells in male/female twins generated by the Cornish pasty culture; and (3) to detect female half of the embryo in artificially generated bilateral gynandromorphs. A rapid, PCR based pre-screening step increases the efficiency of obtaining desired donor/host sex combination from 25% to 100%. For most avian chimera studies, this female-specific in situ probe is a low cost alternative to the commonly used QCPN antibody and to ubiquitous-GFP chicken strains which are not widely available to the research community. © 2014 Wiley Periodicals, Inc.

Embryo selection using time-lapse analysis (Early Embryo Viability Assessment) in conjunction with standard morphology: a prospective two-center pilot study.

PubMed

Kieslinger, Dorit C; De Gheselle, Stefanie; Lambalk, Cornelis B; De Sutter, Petra; Kostelijk, E Hanna; Twisk, Jos W R; van Rijswijk, Joukje; Van den Abbeel, Etienne; Vergouw, Carlijn G

2016-11-01

Does prospective embryo selection using the results from the Eava Test (Early Embryo Viability Assessment) in combination with standard morphology increase the pregnancy rate of IVF and ICSI patients compared to embryo selection based on morphology only? Embryo selection using the Eeva Test plus standard morphology on Day 3 results in comparable pregnancy rates as conventional morphological embryo selection. Time-lapse monitoring of embryo development may represent a superior way to culture and select embryos in vitro. The Eeva Test records the development of each embryo with a cell-tracking system and predicts the likelihood (High, Medium or Low) that an embryo will form a blastocyst based on an automated analysis of early cell division timings. This trial was designed as a prospective, observational, two-center pilot study with a propensity matched control group. The analysis involved 280 of 302 enrolled patients who were included in the Eeva Test group in 2013 and 560 control patients who were treated in the years 2011-2013. The majority of transfers (98%) were single embryo transfers. Two academic hospitals (VUmc Amsterdam and UZ Gent) enrolled patients <41 years old, with <3 previous attempts and ≥5 normally fertilized eggs. Propensity matching was used to identify a propensity matched control group from a cohort of 1777 patients based on age, cycle number, oocyte number and number of fertilized oocytes. There was no difference in patient baseline characteristics between the two groups. The ongoing pregnancy rate (OPR) of patients enrolled in the Eeva Test group (34.3%; 96/280) did not differ significantly from the OPR in the propensity matched control group (34.6%, 194/560; P = 0.92). However, significantly less top quality embryos (eight-cell embryos with ≤25% fragmentation) were transferred in the Eeva Test group compared to the propensity matched control group (70.4% vs. 82.3%; P < 0.001). The transfer of Eeva High and Medium embryos resulted in a

The first whole transcriptomic exploration of pre-oviposited early chicken embryos using single and bulked embryonic RNA-sequencing.

PubMed

Hwang, Young Sun; Seo, Minseok; Choi, Hee Jung; Kim, Sang Kyung; Kim, Heebal; Han, Jae Yong

2018-04-01

The chicken is a valuable model organism, especially in evolutionary and embryology research because its embryonic development occurs in the egg. However, despite its scientific importance, no transcriptome data have been generated for deciphering the early developmental stages of the chicken because of practical and technical constraints in accessing pre-oviposited embryos. Here, we determine the entire transcriptome of pre-oviposited avian embryos, including oocyte, zygote, and intrauterine embryos from Eyal-giladi and Kochav stage I (EGK.I) to EGK.X collected using a noninvasive approach for the first time. We also compare RNA-sequencing data obtained using a bulked embryo sequencing and single embryo/cell sequencing technique. The raw sequencing data were preprocessed with two genome builds, Galgal4 and Galgal5, and the expression of 17,108 and 26,102 genes was quantified in the respective builds. There were some differences between the two techniques, as well as between the two genome builds, and these were affected by the emergence of long intergenic noncoding RNA annotations. The first transcriptome datasets of pre-oviposited early chicken embryos based on bulked and single embryo sequencing techniques will serve as a valuable resource for investigating early avian embryogenesis, for comparative studies among vertebrates, and for novel gene annotation in the chicken genome.

Effects of in ovo feeding of L-arginine on the development of digestive organs, intestinal function and post-hatch performance of broiler embryos and hatchlings.

PubMed

Gao, T; Zhao, M M; Li, Y J; Zhang, L; Li, J L; Yu, L L; Gao, F; Zhou, G H

2018-02-01

This study was to investigate the effects of in ovo feeding (IOF) L-arginine (Arg) solution on the development of digestive organs, the duodenal mucosa of broiler embryos and hatchlings, and the growth performance of chicks during the first week post-hatch. A total of 720 fertilized eggs with similar weight were randomly allocated to three groups, consisting of eight replicates of 30 eggs each. Three treatments were arranged as non-injected control, diluent-injected (0.75% NaCl solution) group and Arg solution-injected group containing 1% Arg, dissolved in diluent. At 17.5 days of incubation, 0.6 ml of IOF solution was injected into amniotic fluid of each egg of injected groups. Results showed IOF of Arg solution increased (p < .05) the chick embryo weight at 19 days of incubation; the body weight gain of post-hatch broilers during 1-7 days; the weights of liver, pancreas, proventriculus and gizzard; the concentrations of duodenal ghrelin, vasoactive intestinal peptide and glucagon-like peptide 2; and the duodenum mucosal enzyme activities of alkaline phosphatase, maltase, sucrase and inducible nitric oxide synthase of 7-day-old post-hatch broilers compared with other groups. The IOF of Arg solution also increased (p < .05) the villus height (VH) and the ratio of VH to crypt depth (CD) and decreased (p < .05) the CD in duodenum of broiler embryos and post-hatch hatchlings, except for the CD at 19 days of incubation. In conclusion, IOF of 1% Arg solution into the amnion at 17.5 days of incubation could improve the development of digestive organs, the duodenal morphology, the releasing of gastrointestinal hormones and mucosal enzyme activities of broiler embryos and hatchlings and finally the growth performance of chicks during the first week post-hatch. Therefore, IOF of appropriate Arg solution could be an effective technology for regulating early nutrition supply and subsequent growth development in poultry industry. © 2017 Blackwell Verlag GmbH.

Paternal Diet-Induced Obesity Retards Early Mouse Embryo Development, Mitochondrial Activity and Pregnancy Health

PubMed Central

Binder, Natalie K.; Hannan, Natalie J.; Gardner, David K.

2012-01-01

Worldwide, 48% of adult males are overweight or obese. An association between infertility and excessive body weight is now accepted, although focus remains primarily on females. It has been shown that parental obesity results in compromised embryo development, disproportionate changes in embryo metabolism and reduced blastocyst cell number. The aim of this study was to determine whether paternal obesity has negative effects on the resultant embryo. Specifically, using in vitro fertilisation (IVF), we wanted to isolate the functional effects of obesity on sperm by examining the subsequent embryo both pre- and post-implantation. Epididymal sperm was collected from age matched normal and obese C57BL/6 mice and cryopreserved for subsequent IVF with oocytes collected from Swiss females (normal diet/weight). Obesity was induced in male mice by feeding a high fat diet of 22% fat for 10 weeks. Resultant embryos were cultured individually and development monitored using time-lapse microscopy. Paternal obesity resulted in a significant delay in preimplantation embryo development as early as syngamy (P<0.05). Metabolic parameters were measured across key developmental stages, demonstrating significant reduction in mitochondrial membrane potential (P<0.01). Blastocysts were stained to determine trophectoderm (TE) and inner cell mass (ICM) cell numbers, revealing significant differences in the ratio of cell allocation to TE and ICM lineages (P<0.01). Functional studies examining blastocyst attachment, growth and implantation demonstrated that blastocysts derived from sperm of obese males displayed significantly reduced outgrowth on fibronectin in vitro (P<0.05) and retarded fetal development in vivo following embryo transfer (P<0.05). Taken together, these data clearly demonstrate that paternal obesity has significant negative effects on the embryo at a variety of key early developmental stages, resulting in delayed development, reduced placental size and smaller offspring

Changes in Oscillatory Dynamics in the Cell Cycle of Early Xenopus laevis Embryos

PubMed Central

Tsai, Tony Y.-C.; Theriot, Julie A.; Ferrell, James E.

2014-01-01

During the early development of Xenopus laevis embryos, the first mitotic cell cycle is long (∼85 min) and the subsequent 11 cycles are short (∼30 min) and clock-like. Here we address the question of how the Cdk1 cell cycle oscillator changes between these two modes of operation. We found that the change can be attributed to an alteration in the balance between Wee1/Myt1 and Cdc25. The change in balance converts a circuit that acts like a positive-plus-negative feedback oscillator, with spikes of Cdk1 activation, to one that acts like a negative-feedback-only oscillator, with a shorter period and smoothly varying Cdk1 activity. Shortening the first cycle, by treating embryos with the Wee1A/Myt1 inhibitor PD0166285, resulted in a dramatic reduction in embryo viability, and restoring the length of the first cycle in inhibitor-treated embryos with low doses of cycloheximide partially rescued viability. Computations with an experimentally parameterized mathematical model show that modest changes in the Wee1/Cdc25 ratio can account for the observed qualitative changes in the cell cycle. The high ratio in the first cycle allows the period to be long and tunable, and decreasing the ratio in the subsequent cycles allows the oscillator to run at a maximal speed. Thus, the embryo rewires its feedback regulation to meet two different developmental requirements during early development. PMID:24523664

The effect of flurbiprofen on the development of anencephaly in early stage chicken embryos.

PubMed

Özeren, Ersin; Er, Uygur; Güvenç, Yahya; Demirci, Adnan; Arıkök, Ata Türker; Şenveli, Engin; Ergün, Rüçhan Behzat

2015-04-01

The study investigated the effect of flurbiprofen on the development of anencephaly in early stage chicken embryos. We looked at four groups with a total of 36 embryos. There was a control group, a normal saline group, a normal-dose group and a high-dose group with ten, ten, eight and eight eggs with embryo respectively. Two embryos in the control group, studied with light microscopy at 48 h, were consistent with 28-29 hours' incubation in the Hamburger-Hamilton System. They had open neural tubes. The other embryos in this group were considered normal. One embryo in the normal saline group was on the occlusion stage at 48 h. One embryo showed an open neural tube. They were compatible with 28-29 hours' incubation in the Hamburger-Hamilton system. The remaining eight embryos showed normal development. In the normal dose group, one embryo showed underdevelopment of the embryonic disc and the embryo was dead. In four embryos, the neural tubes were open. One cranial malformation was found that was complicated with anencephaly in one embryo. In two embryos the neural tubes were closed, as they showed normal development, and they reached their expected stages according to the Hamburger-Hamilton classification. There was no malformation or growth retardation. Four experimental embryos were anencephalic in the high dose group, and three embryos had open neural tubes. One embryo exhibited both anencephaly and a neural tube closure defect. None of the embryos in this group showed normal development. Even the usual therapeutic doses of flurbiprofen increased the risk of neural tube defect. Flurbiprofen was found to significantly increase the risk of anencephaly. The provision of improved technical materials and studies with larger sample sizes will reveal the stage of morphological disruption during the development of embryos.

Naïve Chicks Prefer Hollow Objects

PubMed Central

Schill, Jana; Nencini, Andrea Maria; Vallortigara, Giorgio

2016-01-01

Biological predispositions influence approach and avoid responses from the time of birth or hatching. Neonates of species that require parental care (e.g. human babies and chicks of the domestic fowl) are attracted by stimuli associated with animate social partners, such as face-like configurations, biological motion and self-propulsion. The property of being filled is used as a cue of animacy by 8-month-old human infants but it is not known whether this reflects the effect of previous experience. We used chicks of the domestic fowl (Gallus gallus) to investigate whether the property of being filled vs. hollow elicits spontaneous or learned preferences. To this aim we tested preferences of naïve and imprinted chicks for hollow and closed cylinders. Contrary to our expectations, we documented an unlearned attraction for hollow stimuli. The preference for hollow stimuli decreased when chicks were imprinted on filled stimuli but did not increase when chicks were imprinted on hollow stimuli, suggesting that hollowness is not crucial to determine affiliative responses for imprinting objects. When chicks were imprinted on occluded stimuli that could be either filled or hollow, the preference for hollow stimuli emerged again, showing that imprinting does not disrupt the spontaneous preference for hollow objects. Further experiments revealed that hollow objects were mainly attractive by means of depth cues such as darker innards, more than as places to hide or as objects with high contrast. Our findings point to predisposed preferences for hollow objects, and suggest that early predispositions might be driven by factors different from animacy cues. PMID:27851773

Comparative effects of in ovo versus subcutaneous administration of the Marek's disease vaccine and pre-placement holding time on the early post-hatch quality of Ross × Ross 708 broiler chicks.

PubMed

Peebles, E D; Barbosa, T M; Cummings, T S; Dickson, J; Womack, S K

2016-09-01

Effects of method of administration [moa; in ovo (i.o.) or s.c.] of the Marek's disease vaccine and pre-placement holding time (pht) on early post-hatch male broiler chick quality was investigated. Sixty-five Ross × Ross 708 broiler hatching eggs were randomly set in each of 15 replicate trays (blocks) belonging to each of 4 pre-assigned moa and pht treatment combinations (3,900 total eggs) in a single stage Jamesway incubator. Eggs that were i.o.-vaccinated received injections at 18 d of incubation and male chicks from eggs that were not i.o.-injected were vaccinated by s.c. injection at hatch. The i.o. injections (50 μL) were delivered by a commercial multi-egg injector and the s.c. injections (200 μL) were delivered by an automatic pneumatic s.c. injector. Male chicks from each moa group also were subjected to either a 4 or 18 h pht. At hatch and placement total and yolk-free BW; body length; body mass index; yolk sac weight; yolk-free body and yolk sac weights as percentages of total BW; and yolk-free body and yolk moisture concentrations were determined. Chick BW also was determined at 7 d of age. Hatchability of fertile eggs was not affected by i.o. injection. However, at hatch, body length was increased and body mass index was decreased in response to i.o. injection. No main effect of moa or an interactive effect with pht was observed for the above variables at placement. However, body length was longer and body mass was lower in the 18 h than in the 4 h pht chicks. Placement yolk sac and body weights, and the 7 d BW of 18 h pht chicks was also lower than that of 4 h pht chicks. In conclusion, prolonging pht for 14 h adversely affected early chick quality, whereas i.o. injection did not negatively affect the early post-hatch quality of Ross × Ross 708 broiler chicks whether or not they were held for 4 or 18 h prior to placement. © 2016 Poultry Science Association Inc.

The mRNA-bound proteome of the early fly embryo

PubMed Central

Wessels, Hans-Hermann; Imami, Koshi; Baltz, Alexander G.; Kolinski, Marcin; Beldovskaya, Anastasia; Selbach, Matthias; Small, Stephen; Ohler, Uwe; Landthaler, Markus

2016-01-01

Early embryogenesis is characterized by the maternal to zygotic transition (MZT), in which maternally deposited messenger RNAs are degraded while zygotic transcription begins. Before the MZT, post-transcriptional gene regulation by RNA-binding proteins (RBPs) is the dominant force in embryo patterning. We used two mRNA interactome capture methods to identify RBPs bound to polyadenylated transcripts within the first 2 h of Drosophila melanogaster embryogenesis. We identified a high-confidence set of 476 putative RBPs and confirmed RNA-binding activities for most of 24 tested candidates. Most proteins in the interactome are known RBPs or harbor canonical RBP features, but 99 exhibited previously uncharacterized RNA-binding activity. mRNA-bound RBPs and TFs exhibit distinct expression dynamics, in which the newly identified RBPs dominate the first 2 h of embryonic development. Integrating our resource with in situ hybridization data from existing databases showed that mRNAs encoding RBPs are enriched in posterior regions of the early embryo, suggesting their general importance in posterior patterning and germ cell maturation. PMID:27197210

ULTRASTRUCTURAL ORGANIZATION OF CILIA AND BASAL BODIES OF THE EPITHELIUM OF THE CHOROID PLEXUS IN THE CHICK EMBRYO

PubMed Central

Doolin, Paul F.; Birge, Wesley J.

1966-01-01

Ultrastructural studies were performed on normal and abnormal cilia and basal bodies associated with the choroidal epithelium of the chick embryo. Tissues were prepared in each of several fixatives including: 1% osmium tetroxide, in both phosphate and veronal acetate buffers; 2% glutaraldehyde, followed by postfixation in osmium tetroxide; 1% potassium permanganate in veronal acetate buffer. Normal cilia display the typical pattern of 9 peripheral doublets and 2 central fibers, as well as a system of 9 secondary fibers. The latter show distinct interconnections between peripheral and central fibers. Supernumerary fibers were found to occur in certain abnormal cilia. The basal body is complex, bearing 9 transitional fibers at the distal end and numerous cross-striated rootlets at the proximal end. The distal end of the basal body is delimited by a basal plate of moderate density. The tubular cylinder consists of 9 triple fibers. The C subfibers end at the basal plate, whereas subfibers A and B continue into the shaft of the cilium. The 9 transitional fibers radiate out from the distal end of the basal body, ending in bulblike terminal enlargements which are closely associated with the cell membrane in the area of the basal cup. One or 2 prominent basal feet project laterally from the basal body. These structures characteristically show several dense cross-bands and, on occasion, are found associated with microtubules. PMID:5335827

Expression of genes involved in early cell fate decisions in human embryos and their regulation by growth factors.

PubMed

Kimber, S J; Sneddon, S F; Bloor, D J; El-Bareg, A M; Hawkhead, J A; Metcalfe, A D; Houghton, F D; Leese, H J; Rutherford, A; Lieberman, B A; Brison, D R

2008-05-01

Little is understood about the regulation of gene expression in human preimplantation embryos. We set out to examine the expression in human preimplantation embryos of a number of genes known to be critical for early development of the murine embryo. The expression profile of these genes was analysed throughout preimplantation development and in response to growth factor (GF) stimulation. Developmental expression of a number of genes was similar to that seen in murine embryos (OCT3B/4, CDX2, NANOG). However, GATA6 is expressed throughout preimplantation development in the human. Embryos were cultured in IGF-I, leukaemia inhibitory factor (LIF) or heparin-binding EGF-like growth factor (HBEGF), all of which are known to stimulate the development of human embryos. Our data show that culture in HBEGF and LIF appears to facilitate human embryo expression of a number of genes: ERBB4 (LIF) and LIFR and DSC2 (HBEGF) while in the presence of HBEGF no blastocysts expressed EOMES and when cultured with LIF only two out of nine blastocysts expressed TBN. These data improve our knowledge of the similarities between human and murine embryos and the influence of GFs on human embryo gene expression. Results from this study will improve the understanding of cell fate decisions in early human embryos, which has important implications for both IVF treatment and the derivation of human embryonic stem cells.

Effect of two different commercially available white light LED fixtures on broiler hatchability and chick quality.

PubMed

Archer, G S

2018-06-01

1. The objective of this study was to evaluate the effect of two different spectra of white light on hatchability and chick quality of broiler chickens. 2. A total of 8424 Ross 708 broiler eggs were divided over three light exposure treatments during incubation: No light (DARK), a light emitting diode (LED) light with high levels of blue light (BLUE), or a LED light with high levels of red light (RED). Hatchability, embryo mortality and chick quality were assessed at hatch. 3. DARK had a higher percentage of chicks with unhealed navels (21.1 ± 1.3%) and fewer overall chicks with no defects (77.0 ± 1.2%) compared to both the BLUE (9.9 ± 0.9% and 88.4 ± 1.1%) and RED treatments (7.7 ± 0.8% and 90.2 ± 1.0%). 4. Both the BLUE (80.9 ± 1.0%) and RED treatments (82.9 ± 1.4%) had higher hatchability of fertile eggs than the DARK treatment (76.0 ± 2.2%). 5. These results indicate that either of these LED fixtures could be used to improve hatchability and chick quality in broiler chickens. Utilising these types of lightings in commercial hatcheries will improve the efficiency via increased hatchability and quality of the chicks hatched.

[Observation in situ of differentiation from PGC to hematopoietic system cells in chicken embryo].

PubMed

Zhou, Dong-Yu; Liu, Rong-Xiu; Pei, Yue-Hu

2009-02-01

To study the relationship between hematopoiesis and primordial germ cells, chick embryos at different developing stages were flatbed and located. After fixed by glutaral, the embryos were PAS and HE stained respectively, dehydrated serially, transparent, mounted, and were observed in situ or in cut sheet condition. The results showed: (1) the cellule amorphous and the disposition in chick embryo of PGCs were coincident no matter stained by PAS or HE staining, and HE staining could disclose the morphologic characteristics more clearly, exactly and completely; (2) genesis of blood island could be observed at the boundary of light and dark region of the extraembryonic blastoderm at about 26 hours; (3) both the blood vessel endothelium cells and free cells of the blood island were differentiated from PGCs. The generating of genuine yolk sac was at about 44 - 48 hours. It is concluded that the initial anatomic site of blood island genesis may be is mesoblast of extraembryonic blastoderm rather than the yolk sac; the blood vessel endothelium cells and the blood cells are generated parallel; the PGCs are the common ancestry of angioblast and HSC.

Impaired imprinting and social behaviors in chicks exposed to mifepristone, a glucocorticoid receptor antagonist, during the final week of embryogenesis.

PubMed

Nishigori, Hideo; Kagami, Keisuke; Nishigori, Hidekazu

2014-03-15

The effects of glucocorticoid receptor dysfunction during embryogenesis on the imprinting abilities and social behaviors of hatchlings were examined using "fertile hen's egg-embryo-chick" system. Of embryos treated with mifepristone (0.4μmol/egg) on day 14, over 75% hatched a day later than the controls (day 22) without external anomalies. The mifepristone-treated hatchlings were assayed for imprinting ability on post-hatching day 2 and for social behaviors on day 3. The findings were as follows: imprinting ability (expressed as preference score) was significantly lower in mifepristone-treated hatchlings than in controls (0.65±0.06 vs. 0.92±0.02, P<0.005). Aggregation tests to evaluate the speed (seconds) required for four chicks, individually isolated with cardboard dividers in a box, to form a group after removal of the barriers showed that aggregation was significantly slower in mifepristone-treated hatchlings than in controls (8.7±1.1 vs. 2.6±0.3, P<0.001). In belongingness tests to evaluate the speed (seconds) for a chick isolated at a corner to join a group of three chicks placed at the opposite corner, mifepristone-treated hatchlings took significantly longer than controls (4.5±0.4/40 cm vs. 2.4±0.08/40 cm, P<0.001). In vocalization tests, using a decibel meter to measure average decibel level/30s (chick vocalization), mifepristone-treated hatchlings had significantly weaker vocalizations than controls (14.2±1.9/30s vs. 26.4±1.3/30s P<0.001). In conclusion, glucocorticoid receptor dysfunction during the last week embryogenesis altered the programming of brain development, resulting in impaired behavioral activities in late life. Copyright © 2013 Elsevier B.V. All rights reserved.

No evidence of temperature-dependent sex determination or sex-biased embryo mortality in the chicken.

PubMed

Collins, K E; Jordan, B J; McLendon, B L; Navara, K J; Beckstead, R B; Wilson, J L

2013-12-01

Skewing the sex ratio at hatch in commercial poultry would be economically beneficial to the poultry industry. The existence of temperature-dependent sex determination is uncertain in birds. This experiment investigated if incubation temperatures skew sex ratios of commercial broilers. Three incubators were each set at a hot (38.3°C), standard (37.5°C), or cool (36.7°C) single-stage incubation temperature one time over 3 trials to eliminate incubator effect as a Latin square design. Sex ratios of hatched chicks and dead embryos were monitored. In one trial, embryo weights were evaluated. The percentages of male hatched chicks did not differ based on incubation temperature (P = 0.4486; 49.5% in the hot treatment, 51.4% at standard temperature, and 49.8% in the cool treatment). The percent hatch of eggs set was lower in the hot treatment (83.6%) than the standard (93.5%) and cool (91.6%) treatments (P < 0.0001) with greater late embryonic mortality in the hot treatment (P < 0.0001); however, the sex ratio of dead embryos did not differ among treatments (P = 0.9863). Pooled data of embryo mortality found no sex-biased embryo mortality with a female/male sex ratio of 1.22:1 (χ(2) = 1.27; P = 0.2596). Embryos from the hot treatment were heavier than those from the standard treatment by d 14 of incubation and were heavier than the embryos from the cool treatment by d 9 of incubation (P < 0.0001). These data indicate that incubation temperature affects embryonic mortality and embryonic growth rate, but it does not affect the sex ratio of broiler chickens. Additionally, no evidence was found for sex-biased embryo mortality in commercial broilers even at the incubation temperatures of this study.

PreImplantation Factor (PIF) correlates with early mammalian embryo development-bovine and murine models

PubMed Central

2011-01-01

Background PreImplantation Factor (PIF), a novel peptide secreted by viable embryos is essential for pregnancy: PIF modulates local immunity, promotes decidual pro-adhesion molecules and enhances trophoblast invasion. To determine the role of PIF in post-fertilization embryo development, we measured the peptide's concentration in the culture medium and tested endogenous PIF's potential trophic effects and direct interaction with the embryo. Methods Determine PIF levels in culture medium of multiple mouse and single bovine embryos cultured up to the blastocyst stage using PIF-ELISA. Examine the inhibitory effects of anti-PIF-monoclonal antibody (mAb) added to medium on cultured mouse embryos development. Test FITC-PIF uptake by cultured bovine blastocysts using fluorescent microscopy. Results PIF levels in mouse embryo culture medium significantly increased from the morula to the blastocyst stage (ANOVA, P = 0.01). In contrast, atretic embryos medium was similar to the medium only control. Detectable - though low - PIF levels were secreted already by 2-cell stage mouse embryos. In single bovine IVF-derived embryos, PIF levels in medium at day 3 of culture were higher than non-cleaving embryos (control) (P = 0.01) and at day 7 were higher than day 3 (P = 0.03). In non-cleaving embryos culture medium was similar to medium alone (control). Anti-PIF-mAb added to mouse embryo cultures lowered blastocyst formation rate 3-fold in a dose-dependent manner (2-way contingency table, multiple groups, X2; P = 0.01) as compared with non-specific mouse mAb, and medium alone, control. FITC-PIF was taken-up by cultured bovine blastocysts, but not by scrambled FITC-PIF (control). Conclusions PIF is an early embryo viability marker that has a direct supportive role on embryo development in culture. PIF-ELISA use to assess IVF embryo quality prior to transfer is warranted. Overall, our data supports PIF's endogenous self sustaining role in embryo development and the utility of PIF

Early embryonic brain development in rats requires the trophic influence of cerebrospinal fluid.

PubMed

Martin, C; Alonso, M I; Santiago, C; Moro, J A; De la Mano, A; Carretero, R; Gato, A

2009-11-01

Cerebrospinal fluid has shown itself to be an essential brain component during development. This is particularly evident at the earliest stages of development where a lot of research, performed mainly in chick embryos, supports the evidence that cerebrospinal fluid is involved in different mechanisms controlling brain growth and morphogenesis, by exerting a trophic effect on neuroepithelial precursor cells (NPC) involved in controlling the behaviour of these cells. Despite it being known that cerebrospinal fluid in mammals is directly involved in corticogenesis at fetal stages, the influence of cerebrospinal fluid on the activity of NPC at the earliest stages of brain development has not been demonstrated. Here, using "in vitro" organotypic cultures of rat embryo brain neuroepithelium in order to expose NPC to or deprive them of cerebrospinal fluid, we show that the neuroepithelium needs the trophic influence of cerebrospinal fluid to undergo normal rates of cell survival, replication and neurogenesis, suggesting that NPC are not self-sufficient to induce their normal activity. This data shows that cerebrospinal fluid is an essential component in chick and rat early brain development, suggesting that its influence could be constant in higher vertebrates.

Transcriptome analyses of rhesus monkey preimplantation embryos reveal a reduced capacity for DNA double-strand break repair in primate oocytes and early embryos

PubMed Central

Wang, Xinyi; Liu, Denghui; He, Dajian; Suo, Shengbao; Xia, Xian; He, Xiechao; Han, Jing-Dong J.; Zheng, Ping

2017-01-01

Preimplantation embryogenesis encompasses several critical events including genome reprogramming, zygotic genome activation (ZGA), and cell-fate commitment. The molecular basis of these processes remains obscure in primates in which there is a high rate of embryo wastage. Thus, understanding the factors involved in genome reprogramming and ZGA might help reproductive success during this susceptible period of early development and generate induced pluripotent stem cells with greater efficiency. Moreover, explaining the molecular basis responsible for embryo wastage in primates will greatly expand our knowledge of species evolution. By using RNA-seq in single and pooled oocytes and embryos, we defined the transcriptome throughout preimplantation development in rhesus monkey. In comparison to archival human and mouse data, we found that the transcriptome dynamics of monkey oocytes and embryos were very similar to those of human but very different from those of mouse. We identified several classes of maternal and zygotic genes, whose expression peaks were highly correlated with the time frames of genome reprogramming, ZGA, and cell-fate commitment, respectively. Importantly, comparison of the ZGA-related network modules among the three species revealed less robust surveillance of genomic instability in primate oocytes and embryos than in rodents, particularly in the pathways of DNA damage signaling and homology-directed DNA double-strand break repair. This study highlights the utility of monkey models to better understand the molecular basis for genome reprogramming, ZGA, and genomic stability surveillance in human early embryogenesis and may provide insights for improved homologous recombination-mediated gene editing in monkey. PMID:28223401

Effects of embryo size at transfer (whole versus demi) and early pregnancy progesterone supplementation on embryo growth and pregnancy-specific protein bovine concentrations in recipient dairy heifers.

PubMed

Lopes-da-Costa, L; Chagas e Silva, J; Deloche, M C; Jeanguyot, N; Humblot, P; Horta, A E M

2011-08-01

The objectives of this study were to evaluate embryonic size and survival, plasma progesterone (P4) and pregnancy-specific protein bovine (PSPB) concentrations in early pregnancies (n = 99) following the transfer of one whole (n = 66) or one demi (n = 33) embryo to recipient virgin dairy heifers. The experiment was designed to evaluate the fixed effects of embryo size at transfer (whole or demi embryo) on Day 7 of the estrous cycle (Day 0 = estrus) and P4 supplementation between Days 7 to 19 through an intravaginal device (yes or no) on plasma P4 and PSPB concentrations and on embryo measurements. Plasma P4 concentrations were measured by RIA on Days 0, 7, 14, 19, 21, 25, 35, 42, 49, 56 and 63 of pregnancy and, PSPB concentrations were measured by ELISA on Days 7, 21, 25, 35, 42, 49, 56 and 63. The presence of an embryonic vesicle was detected on Day 25, embryonic/fetal movements and heartbeat were evaluated on Days 42 and 63 and embryo measurements [crown-rump length (CRL) and width at mid body] were obtained on Day 42 through ultrasonography. In non-supplemented pregnancies, Day 42 whole embryos had higher (P < 0.05) CRL and width than demi embryos, but the difference averaged only 1 to 2 mm. In P4 supplemented pregnancies, whole and demi embryos attained a similar size on Day 42 of pregnancy. Embryo size at transfer, early exogenous P4 supplementation and their interactions had no effects (P > 0.05) on plasma P4 concentrations. However, the post-hoc LSD evaluation showed that plasma P4 concentrations on Day 25 were higher (P < 0.001) in whole than in demi embryo derived pregnancies and, that exogenous P4 supplementation increased (P < 0.05) plasma P4 concentrations on Day 19 of pregnancy. The plasma PSPB detection rate on Days 7 to 63 of pregnancy was similar in pregnancies resulting from the transfer of whole and demi embryos. From a total of 93 recipients remaining pregnant until Day 63, plasma PSPB was constantly undetectable on Day 7, was detected in 4% of

Derivation of feline vaccine-associated fibrosarcoma cell line and its growth on chick embryo chorioallantoic membrane - a new in vivo model for veterinary oncological studies.

PubMed

Zabielska, K; Lechowski, R; Król, M; Pawłowski, K M; Motyl, T; Dolka, I; Zbikowski, A

2012-12-01

Feline vaccine associated fibrosarcomas are the second most common skin tumor in cats. Methods of treatment are: surgery, chemotherapy and radiotherapy. Nevertheless, the usage of cytostatics in feline vaccine associated sarcoma therapy is limited due to their adverse side effects, high toxicity and low biodistribution after i.v. injection. Therefore, much research on new therapeutic drugs is being conducted. In human medicine, the chick embryo chorioallantoic membrane (CAM) model is used as a cheap and easy to perform assay to assess new drug effectiveness in cancer treatment. Various human cell lines have different tumors growth on CAM. In veterinary medicine such model has not been described yet. In the present article derivation of feline vaccine associated fibrosarcoma cell line and its growth on CAM is described. The cell line and the tumor grown were confirmed by histopathological and immunohistochemical examination. As far as we believe, this is the first attempt to create such model, which may be used for further in vivo studies in veterinary oncology.

[Breeding biology of the whiskered auklet (Aethia pygmaea): incubation, chick growth, and feather ontogenesis].

PubMed

Koniukhov, N B; Zubakin, V A; Williams, J; Fischer, J

2000-01-01

This is the second publication on the results of studies of the whiskered auklet breeding biology on Buldir Island. In 1993, according to the time of chick hatching the egg-laying period began in late April-early May. The single egg was incubated by both parents, which relieved each other once a day, usually at early night. Among the chicks under observation, the first hatched on June 11; the median of hatching was on June 17. After hatching, the egg shell usually remained in the nest. The chick was continuously brooded by one of parents for the first several days but since the age of 7-9 days, it stayed in the nest by itself during the daytime. Each parent fed the chick once a day, at early night, although occasional feedings were recorded also during daytime and at dawn. A newly hatched chick was covered by typical embryonal (natal) down. The remiges, rectrices, their coverts, and large feathers on pteryla humeralis had a mesoptile stage during their growth (the second down generation). The juvenile plumage consisted of semiplumes of types I and II and contour feathers of type I and, possibly, type II. In fledglings, the ornamental feathers were underdeveloped: the crest was absent and facial plumes only began growing. By reaching 100 g, the chicks left their nests at the age of about 37 days. A longer nesting period than in other Aethia auklets appears to be related to a low feeding rate due to the nocturnal activity in the colony.

Expression of the voltage-sensing phosphatase gene in the chick embryonic tissues and in the adult cerebellum.

PubMed

Yamaguchi, Shinji; Aoki, Naoya; Kitajima, Takaaki; Okamura, Yasushi; Homma, Koichi J

2014-10-01

Voltage-sensing phosphatase (VSP) consists of a transmembrane voltage sensor domain (VSD) and the cytoplasmic domain with phosphoinositide-phosphatase activities. It operates as the voltage sensor and directly translates membrane potential into phosphoinositide turnover by coupling VSD to the cytoplasmic domain. VSPs are evolutionarily conserved from marine invertebrate up to humans. Recently, we demonstrated that ectopic expression of the chick ortholog of VSP, Gg-VSP, in a fibroblast cell line caused characteristic cell process outgrowths. Co-expression of chick PTEN suppressed such morphological change, suggesting that VSP regulates cell shape by increasing PI(3,4)P2. However, the in vivo function of Gg-VSP remains unclear. Here, we showed that in chick embryos Gg-VSP is expressed in the stomach, mesonephros, pharyngeal arch, limb bud, somites, floor plate of neural tube, and notochord. In addition, both Gg-VSP transcripts and the protein were found in the cerebellar Purkinje neurons. These findings provide an insight into the physiological functions of VSP.

Inhibitors of procollagen C-terminal proteinase block gastrulation and spicule elongation in the sea urchin embryo.

PubMed

Huggins, L G; Lennarz, W J

2001-08-01

In the sea urchin embryo, inhibition of collagen processing and deposition affects both gastrulation and embryonic skeleton (spicule) formation. It has been found that cell-free extracts of gastrula-stage embryos of Strongylocentrotus purpuratus contain a procollagen C-terminal proteinase (PCP) activity. A rationally designed non-peptidic organic hydroxamate, which is a potent and specific inhibitor of human recombinant PCP (FG-HL1), inhibited both the sea urchin PCP as well as purified chick embryo tendon PCP. In the sea urchin embryo, FG-HL1 inhibited gastrulation and blocked spicule elongation, but not spicule nucleation. A related compound with a terminal carboxylate rather than a hydroxamate (FG-HL2) did not inhibit either chick PCP or sea urchin PCP activity in a procollagen-cleavage assay. However, FG-HL2 did block spicule elongation without affecting spicule nucleation or gastrulation. Neither compound was toxic, because their effects were reversible on removal. It was shown that the inhibition of gastrulation and spicule elongation were independent of tissue specification events, because both the endoderm specific marker Endo1 and the primary mesenchyme cell specific marker SM50 were expressed in embryos treated with FG-HL1 and FG-HL2. These results suggest that disruption of the fibrillar collagen deposition in the blastocoele blocks the cell movements of gastrulation and may disrupt the positional information contained within the extracellular matrix, which is necessary for spicule formation.

Development of otoconia in the embryonic chick (Gallus domesticus)

NASA Technical Reports Server (NTRS)

Fermin, C. D.; Igarashi, M.

1985-01-01

In the chick (Gallus domesticus) embryo, otoconium formation started first over the macula sacculi around the 4th day of incubation, and a day later over the macula utriculi. It was determined that each otoconium formed as a result of the segmentation of the immature otolithic membrane, and that the calcium responsible for otoconium calcification was incorporated into the organic matrix of each otoconium in the form of small electron-dense granules (20-150 nm in. diameter). The presence of calcium in these granules was confirmed by histochemical staining with osmic-potassium pyroantimonate, by EDTA chelation, and by X-ray micronanalysis under the electron microscope.

Influence of pre-storage incubation on hatchability traits, thyroid hormones, antioxidative status and immunity of newly hatched chicks at two chicken breeder flock ages.

PubMed

Ebeid, T A; Twfeek, F A; Assar, M H; Bealish, A M; Abd El-Karim, R E; Ragab, M

2017-11-01

Egg storage longer than 7 days is associated with negative effects on hatchability traits. Pre-storage incubation has been a suggested method to reduce the negative effects of long-term storage times by enhancing the developmental stage of the embryo and probably reducing the embryonic stress. The objective of the present study was to investigate the effects of pre-storage incubation and storage time on hatchability characteristics, chick quality and serum thyroid hormones, antioxidative properties and immunoglobulin Y (IgY) concentrations of newly hatched chicks at two breeder flock ages. A total of 8000 fertile eggs were obtained from two different ages of chicken breeder hens (Egyptian local cross, Inshas). Half of the eggs were collected from young breeder hens (28 weeks old) and the other half from old breeder hens (50 weeks old). In each breeder flock age, eggs were distributed in a completely randomized experimental design in a 2×4 factorial arrangement, with two storage periods (4 or 14 days) and four pre-storage incubation durations (0, 4, 6 or 8 h at 37.5°C). At 28 and 50 weeks of age, pre-storage incubation and its interaction with storage period influenced significantly the apparent fertility, hatchability of set eggs and hatchability of fertile eggs and this improvement in hatchability is attributed to the reduction in embryonic mortality (early, intermediate and late). Pre-storage incubation for 6 or 8 h elevated significantly the grade A chicks and reduced the grade B chicks in comparison with non-heated controls. Interestingly, for eggs stored for 14 days, pre-storage incubation for 6 or 8 h enhanced serum triiodothyronine, thyroxine, glutathione peroxidase activity, total antioxidant capacity and IgY concentrations significantly and decreased serum malondialdehyde concentration significantly in the newly hatched chicks. It could be concluded that pre-storage incubation enhanced the hatching results, improved the antioxidative properties, reduced

Bovine oocytes and early embryos express Staufen and ELAVL RNA-binding proteins.

PubMed

Calder, M D; Madan, P; Watson, A J

2008-05-01

RNA-binding proteins (RBP) influence RNA editing, localization, stability and translation and may contribute to oocyte developmental competence by regulating the stability and turnover of oogenetic mRNAs. The expression of Staufen 1 and 2 and ELAVL1, ELAVL2 RNA-binding proteins during cow early development was characterized. Cumulus-oocyte complexes were collected from slaughterhouse ovaries, matured, inseminated and subjected to embryo culture in vitro. Oocyte or preimplantation embryo pools were processed for RT-PCR and whole-mount immunofluorescence analysis of mRNA expression and protein distribution. STAU1 and STAU2 and ELAVL1 mRNAs and proteins were detected throughout cow preimplantation development from the germinal vesicle (GV) oocyte to the blastocyst stage. ELAVL2 mRNAs were detectable from the GV to the morula stage, whereas ELAVL2 protein was in all stages examined and localized to both cytoplasm and nuclei. The findings provide a foundation for investigating the role of RBPs during mammalian oocyte maturation and early embryogenesis.

Supplementation with CTGF, SDF1, NGF, and HGF promotes ovine in vitro oocyte maturation and early embryo development.

PubMed

Wang, D H; Ren, J; Zhou, C J; Han, Z; Wang, L; Liang, C G

2018-05-17

The strategies for improving the in vitro maturation (IVM) of domestic animal oocytes focus on promoting nuclear and cytoplasmic maturation. The identification of paracrine factors and their supplementation in the culture medium represent effective approaches for oocyte maturation and embryo development. This study investigated the effects of paracrine factor supplementation including connective tissue growth factor (CTGF), nerve growth factor (NGF), hepatocyte growth factor (HGF), and stromal derived factor 1 (SDF1) on ovine oocytes and early parthenogenetic embryos using an in vitro culture system. First, we identified the optimal concentrations of CTGF (30 ng/mL), SDF1 (10 ng/mL), NGF (3 ng/mL), and HGF (100 ng/mL) for promoting oocyte maturation, which combined, induced nuclear maturation in 94.19% of oocytes. This combination also promoted cumulus cell expansion and inhibited oocyte/cumulus apoptosis, while enabling a larger proportion (33.04%) of embryos to develop into blastocysts than in the controls and prevented embryo apoptosis. These novel findings demonstrate that the paracrine factors CTGF, SDF1, NGF, and HGF facilitate ovine oocyte and early parthenogenetic embryo development in vitro. Thus, supplementation with these factors may help optimize the IVM of ovine oocytes and early parthenogenetic embryo development strategies. Copyright © 2018 Elsevier Inc. All rights reserved.

Ethanol exposure during the early first trimester equivalent impairs reflexive motor activity and heightens fearfulness in an avian model.

PubMed

Smith, Susan M; Flentke, George R; Kragtorp, Katherine A; Tessmer, Laura

2011-02-01

Prenatal alcohol exposure is a leading cause of childhood neurodevelopmental disability. The adverse behavioral effects of alcohol exposure during the second and third trimester are well documented; less clear is whether early first trimester-equivalent exposures also alter behavior. We investigated this question using an established chick model of alcohol exposure. In ovo embryos experienced a single, acute ethanol exposure that spanned gastrulation through neuroectoderm induction and early brain patterning (19-22h incubation). At 7 days posthatch, the chicks were evaluated for reflexive motor function (wingflap extension, righting reflex), fearfulness (tonic immobility [TI]), and fear/social reinstatement (open-field behavior). Chicks exposed to a peak ethanol level of 0.23-0.28% were compared against untreated and saline-treated controls. Birds receiving early ethanol exposure had a normal righting reflex and a significantly reduced wingflap extension in response to a sudden descent. The ethanol-treated chicks also displayed heightened fearfulness, reflected in increased frequency of TI, and they required significantly fewer trials for its induction. In an open-field test, ethanol treatment did not affect latency to move, steps taken, vocalizations, defecations, or escape attempts. The current findings demonstrate that early ethanol exposure can increase fearfulness and impair aspects of motor function. Importantly, the observed dysfunctions resulted from an acute ethanol exposure during the period when the major brain components are induced and patterned. The equivalent period in human development is 3-4 weeks postconception. The current findings emphasize that ethanol exposure during the early first trimester equivalent can produce neurodevelopmental disability in the offspring. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

Mouse Embryo Compaction.

PubMed

White, M D; Bissiere, S; Alvarez, Y D; Plachta, N

2016-01-01

Compaction is a critical first morphological event in the preimplantation development of the mammalian embryo. Characterized by the transformation of the embryo from a loose cluster of spherical cells into a tightly packed mass, compaction is a key step in the establishment of the first tissue-like structures of the embryo. Although early investigation of the mechanisms driving compaction implicated changes in cell-cell adhesion, recent work has identified essential roles for cortical tension and a compaction-specific class of filopodia. During the transition from 8 to 16 cells, as the embryo is compacting, it must also make fundamental decisions regarding cell position, polarity, and fate. Understanding how these and other processes are integrated with compaction requires further investigation. Emerging imaging-based techniques that enable quantitative analysis from the level of cell-cell interactions down to the level of individual regulatory molecules will provide a greater understanding of how compaction shapes the early mammalian embryo. © 2016 Elsevier Inc. All rights reserved.

Binding of various ovotransferrin fragments to chick-embryo red cells.

PubMed Central

Oratore, A; D'Andrea, G; Moreton, K; Williams, J

1989-01-01

1. The ability of N- and C-terminal half-molecule fragments of hen ovotransferrin to interact with chick red blood cells (CERBC) has been studied under conditions that allow binding of the transferrin to transferrin receptors to take place, but not the delivery of iron to the cell. Two kinds of half-molecule fragments were used: (a) those which can associate with one another to give a dimer resembling native transferrin and (b) those which cannot associate in this way because they lack a few amino acid residues from their C-terminal ends. 2. Neither N nor C half-molecules alone can bind to the CERBC, but, when both are present, tight binding occurs. 3. Whether or not the half-molecules can associate with one another makes little difference to receptor binding. 4. Given that one of the half-molecules is iron-saturated, the presence or absence of iron in the contralateral half-molecule again makes little difference to receptor binding. PMID:2920021

Effect of early addition of bone morphogenetic protein 5 (BMP5) to embryo culture medium on in vitro development and expression of developmentally important genes in bovine preimplantation embryos.

PubMed

García, Elina V; Miceli, Dora C; Rizo, Gabriela; Valdecantos, Pablo A; Barrera, Antonio D

2015-09-01

Previous studies have reported that bone morphogenetic protein 5 (BMP5) is differentially expressed in the isthmus of bovine oviducts and it is present in the oviductal fluid. However, the specific action of this factor is unknown. To evaluate whether BMP5 exerts some effect during early bovine embryo development, gene expression of BMP5, BMP receptors, and the effect of exogenous BMP5 on in vitro development and expression of developmentally important genes were assessed. In experiment 1, pools of embryos at two-cell, four-cell, eight-cell, and blastocyst stages, derived from in vitro fertilization, were collected for analysis of BMP5 and BMP receptors (BMPR1A, BMPR1B, and BMPR2) messenger RNA (mRNA) expression. On the basis of previous results, in experiment 2, presumptive zygotes were cultured for the first 48 hours after insemination in CR1aa medium assaying three different treatments: (1) control (CR1aa); (2) vehicle control (CR1aa + 0.04 mM HCl), and (3) BMP5 treatment (CR1aa + 100 ng/mL of BMP5). The cleavage rate was evaluated 48 hours after insemination (Day 2), and then, embryos were transferred to CR1aa + 10% fetal bovine serum. The blastocyst rate was determined on Day 7. In experiment 3, pools of embryos at two-cell, four-cell, eight-cell, and blastocyst stages, derived from control and BMP5-treated groups, were collected for analysis of ID2 (BMP target gene), OCT4, NANOG, and SOX2 (pluripotency genes) mRNA expression. BMP5 transcripts were not detectable in any of the embryonic stages examined, whereas the relative mRNA abundance of the three BMP receptors analyzed was greater in early embryo development stages before maternal-embryonic transition, raising the possibility of a direct effect of exogenous BMPs on the embryo during the first developmental period. Although early addition of 100 ng/mL of BMP5 to the embryo culture medium had no effect on the cleavage rate, a significantly higher proportion of cleaved embryos developed to the

Early detection and staging of spontaneous embryo resorption by ultrasound biomicroscopy in murine pregnancy.

PubMed

Flores, Luis E; Hildebrandt, Thomas B; Kühl, Anja A; Drews, Barbara

2014-05-10

Embryo resorption is a major problem in human medicine, agricultural animal production and in conservation breeding programs. Underlying mechanisms have been investigated in the well characterised mouse model. However, post mortem studies are limited by the rapid disintegration of embryonic structures. A method to reliably identify embryo resorption in alive animals has not been established yet. In our study we aim to detect embryos undergoing resorption in vivo at the earliest possible stage by ultra-high frequency ultrasound. In a longitudinal study, we monitored 30 pregnancies of wild type C57BI/6 mice using ultra-high frequency ultrasound (30-70 MHz), so called ultrasound biomicroscopy (UBM). We compared the sonoembryology of mouse conceptuses under spontaneous resorption and neighbouring healthy conceptuses and correlated the live ultrasound data with the respective histology. The process of embryo resorption comprised of four stages: first, the conceptus exhibited growth retardation, second, bradycardia and pericardial edema were observed, third, further development ceased and the embryo died, and finally embryo remnants were resorbed by maternal immune cells. In early gestation (day 7 and 8), growth retardation was characterized by a small embryonic cavity. The embryo and its membranes were ill defined or did not develop at all. The echodensity of the embryonic fluid increased and within one to two days, the embryo and its cavity disappeared and was transformed into echodense tissue surrounded by fluid filled caverns. In corresponding histologic preparations, fibrinoid material interspersed with maternal granulocytes and lacunae filled with maternal blood were observed. In later stages (day 9-11) resorption prone embryos were one day behind in their development compared to their normal siblings. The space between Reichert's membrane and inner yolk sac membrane was enlarged The growth retarded embryos exhibited bradycardia and ultimately cessation of heart

Early detection and staging of spontaneous embryo resorption by ultrasound biomicroscopy in murine pregnancy

PubMed Central

2014-01-01

Background Embryo resorption is a major problem in human medicine, agricultural animal production and in conservation breeding programs. Underlying mechanisms have been investigated in the well characterised mouse model. However, post mortem studies are limited by the rapid disintegration of embryonic structures. A method to reliably identify embryo resorption in alive animals has not been established yet. In our study we aim to detect embryos undergoing resorption in vivo at the earliest possible stage by ultra-high frequency ultrasound. Methods In a longitudinal study, we monitored 30 pregnancies of wild type C57BI/6 mice using ultra-high frequency ultrasound (30-70 MHz), so called ultrasound biomicroscopy (UBM). We compared the sonoembryology of mouse conceptuses under spontaneous resorption and neighbouring healthy conceptuses and correlated the live ultrasound data with the respective histology. Results The process of embryo resorption comprised of four stages: first, the conceptus exhibited growth retardation, second, bradycardia and pericardial edema were observed, third, further development ceased and the embryo died, and finally embryo remnants were resorbed by maternal immune cells. In early gestation (day 7 and 8), growth retardation was characterized by a small embryonic cavity. The embryo and its membranes were ill defined or did not develop at all. The echodensity of the embryonic fluid increased and within one to two days, the embryo and its cavity disappeared and was transformed into echodense tissue surrounded by fluid filled caverns. In corresponding histologic preparations, fibrinoid material interspersed with maternal granulocytes and lacunae filled with maternal blood were observed. In later stages (day 9–11) resorption prone embryos were one day behind in their development compared to their normal siblings. The space between Reichert’s membrane and inner yolk sac membrane was enlarged The growth retarded embryos exhibited bradycardia and

Inheritance and Establishment of Gut Microbiota in Chickens

PubMed Central

Ding, Jinmei; Dai, Ronghua; Yang, Lingyu; He, Chuan; Xu, Ke; Liu, Shuyun; Zhao, Wenjing; Xiao, Lu; Luo, Lingxiao; Zhang, Yan; Meng, He

2017-01-01

In mammals, the microbiota can be transmitted from the placenta, uterus, and vagina of the mother to the infant. Unlike mammals, development of the avian embryo is a process isolated from the mother and thus in the avian embryo the gut microbial developmental process remains elusive. To explore the establishment and inheritance of the gut microbiome in the avian embryo, we used the chicken as the model organism to investigate the gut microbial composition in embryos, chicks, and maternal hens. We observed: (1) 28 phyla and 162 genera of microbes in embryos where the dominated genus was Halomonas (79%). (2) 65 genera were core microbiota in all stages with 42% and 62% gut microbial genera of embryo were found in maternal hen and chick, respectively. There was a moderate correlation (0.40) between the embryo and maternal, and 0.52 between the embryo and chick at the family level. (3) Gut microbes that are involved in substance metabolism, infectious disease, and environmental adaptation are enriched in embryos, chicks, and maternal hens, respectively. (4) 94% genera of gut microbial composition were similar among three different chicken breeds which were maintained under similar conditions. Our findings provide evidence to support the hypothesis that part of the microbial colonizers harbored in early embryos were inherited from maternal hens, and the gut microbial abundance and diversity were influenced by environmental factors and host genetic variation during development. PMID:29067020

3D chick embryo chorioallantoic membrane model as an in vivo model to study morphological and histopathological features of feline fibrosarcomas.

PubMed

Zabielska-Koczywąs, Katarzyna; Wojtkowska, Agata; Dolka, Izabella; Małek, Anna; Walewska, Magdalena; Wojtalewicz, Anna; Żbikowski, Artur; Lechowski, Roman

2017-06-26

The chick embryo chorioallantoic membrane (CAM) model is well described in human medicine as a cost-effective, easy to perform preclinical oncological model for observing pro- and antiangiogenic response, tumor biology and metastasis. The main objective of this article was to present the modification of the CAM assay in order to evaluate tumor growth from two feline fibrosarcoma cell lines (FFS1, FFS3) and describe their morphological and histopathological features. The authors described morphological and histopathological features of two feline fibrosarcoma cell lines (FFS1 and FFS3) grown on the CAM. Tumors from the FFS1 cell line showed high malignancy (grade III), while tumors from the FFS3 cell line were grade II. Proliferation markers (Ki-67 and PCNA) were determined and the positive correlation between PCNA and tumor grade (r = 0.8247; p < 0.001) was demonstrated, as opposed to Ki-67. The results obtained indicate that PCNA may be helpful to evaluate the tumor grade, better than Ki-67, for feline fibrosarcomas. However, further investigations of proliferation marker, in bigger number of feline spontaneous fibrosarcomas and feline fibrosarcomas grown on the CAM from different cell lines, are needed to confirm these observations.

Moral uncertainty in bioethical argumentation: a new understanding of the pro-life view on early human embryos.

PubMed

Żuradzki, Tomasz

2014-12-01

In this article, I present a new interpretation of the pro-life view on the status of early human embryos. In my understanding, this position is based not on presumptions about the ontological status of embryos and their developmental capabilities but on the specific criteria of rational decisions under uncertainty and on a cautious response to the ambiguous status of embryos. This view, which uses the decision theory model of moral reasoning, promises to reconcile the uncertainty about the ontological status of embryos with the certainty about normative obligations. I will demonstrate that my interpretation of the pro-life view, although seeming to be stronger than the standard one, has limited scope and cannot be used to limit destructive research on human embryos.

Maternal hCG concentrations in early IVF pregnancies: associations with number of cells in the Day 2 embryo and oocytes retrieved.

PubMed

Tanbo, T G; Eskild, A

2015-12-01

Do number of cells in the transferred cleavage stage embryo and number of oocytes retrieved for IVF influence maternal hCG concentrations in early pregnancies? Compared with transfer of a 2-cell embryo, transfer of a 4-cell embryo results in higher hCG concentrations on Day 12 after transfer, and more than 20 oocytes retrieved were associated with low hCG concentrations. Maternal hCG concentration in very early pregnancy varies considerably among women, but is likely to be an indicator of time since implantation of the embryo into the endometrium, in addition to number and function of trophoblast cells. We followed 1047 pregnancies after IVF/ICSI from oocyte retrieval until Day 12 after embryo transfer. Women were recruited in Norway during the years 2005-2013. Successful pregnancies after transfer of one single embryo that had been cultured for 2 days were included. Maternal hCG was quantified on Day 12 after embryo transfer by chemiluminescence immunoassay, which measures intact hCG and the free β-hCG chain. Information on a successful pregnancy, defined as birth after >16 weeks, was obtained by linkage to the Medical Birth Registry of Norway. Transfer of a 4-cell embryo resulted in higher maternal hCG concentrations compared with transfer of a 2-cell embryo (134.8 versus 87.8 IU/l, P < 0.05). A high number of oocytes retrieved (>20) was associated with low hCG concentrations (P < 0.05). The factors studied explain a limited part of the total variation of hCG concentrations in early pregnancy. Although embryo transfer was performed at the same time after fertilization, we do not know the exact time of implantation. A further limitation to our study is that the number of pregnancies after transfer of a 2-cell embryo was small (27 cases). Number of cells in the transferred embryo and number of oocytes retrieved may influence the conditions and timing for embryo implantation in different ways and thereby influence maternal hCG concentrations. Such knowledge may be

Effect of the combination of white and red LED lighting during incubation on layer, broiler, and Pekin duck hatchability.

PubMed

Archer, G S; Jeffrey, D; Tucker, Z

2017-08-01

Previous research has shown that providing light during incubation can have positive effects on hatchability and chick quality; however, white light alone has been observed to improve these factors only in pigmented broiler eggs and non-pigmented white layer eggs. Monochromatic red light has been shown to improve hatchability in layer eggs. Therefore the objective of this study was to utilize one light fixture that emitted both white and monochromatic red light to determine if this one light source could improve hatchability in both types of chicken eggs and pigmented Pekin duck egg. To determine this, 3 experiments were conducted, the first using White Leghorn eggs (N = 6912), the second using commercial broiler eggs (N = 4608), and the third using commercial Pekin duck eggs (N = 3564) in which eggs were incubated with 12 h of light and 12 h of darkness (LED) or complete darkness (DARK); the light level was 250 lux. Hatchability, embryo mortality, and hatchling quality were measured. In Experiment 1, LED had fewer early dead embryos (P = 0.03), less overall embryo mortality (P = 0.05), fewer chicks with unhealed navels (P < 0.001), fewer chicks with defects (P < 0.001), and a higher percentage of fertile eggs that hatched (P = 0.05) than DARK. In Experiment 2, LED had fewer chicks with unhealed navels (P = 0.003), fewer chicks with defects (P = 0.001), and a higher percentage of fertile eggs that hatched (P = 0.04) than DARK. In Experiment 3, LED had fewer early dead embryos (P = 0.05), lower overall embryo mortality (P = 0.04), and a higher percentage of fertile eggs that hatched (P = 0.05), and had ducklings with lower bodyweights at hatch (P = 0.04) than DARK. These results indicate that providing both white and red light during incubation can improve chick quality across poultry varieties. This type of fixture could be used to improve commercial hatchery efficiency and chick quality. © 2017 Poultry Science Association Inc.

Alcohol exposure alters DNA methylation profiles in mouse embryos at early neurulation

PubMed Central

Liu, Yunlong; Balaraman, Yokesh; Wang, Guohua; Nephew, Kenneth P.; Zhou, Feng C.

2009-01-01

Alcohol exposure during development can cause variable neurofacial deficit and growth retardation known as fetal alcohol spectrum disorders (FASD). The mechanism underlying FASD is not fully understood. However, alcohol, which is known to affect methyl donor metabolism, may induce aberrant epigenetic changes contributing to FASD. Using a tightly controlled whole-embryo culture, we investigated the effect of alcohol exposure (88 mM) at early embryonic neurulation on genome-wide DNA methylation and gene expression in the C57BL/6 mouse. The DNA methylation landscape around promoter CpG islands at early mouse development was analyzed using MeDIP (methylated DNA immunoprecipitation) coupled with microarray (MeDIP-chip). At early neurulation, genes associated with high CpG promoters (HCP) had a lower ratio of methylation but a greater ratio of expression. Alcohol-induced alterations in DNA methylation were observed, particularly in genes on chromosomes 7, 10 and X; remarkably, a >10 fold increase in the number of genes with increased methylation on chromosomes 10 and X was observed in alcohol-exposed embryos with a neural tube defect phenotype compared to embryos without a neural tube defect. Significant changes in methylation were seen in imprinted genes, genes known to play roles in cell cycle, growth, apoptosis, cancer, and in a large number of genes associated with olfaction. Altered methylation was associated with significant (p < 0.01) changes in expression for 84 genes. Sequenom EpiTYPER DNA methylation analysis was used for validation of the MeDIP-chip data. Increased methylation of genes known to play a role in metabolism (Cyp4f13) and decreased methylation of genes associated with development (Nlgn3, Elavl2, Sox21 and Sim1), imprinting (Igf2r) and chromatin (Hist1h3d) was confirmed. In a mouse model for FASD, we show for the first time that alcohol exposure during early neurulation can induce aberrant changes in DNA methylation patterns with associated changes

Alcohol exposure alters DNA methylation profiles in mouse embryos at early neurulation.

PubMed

Liu, Yunlong; Balaraman, Yokesh; Wang, Guohua; Nephew, Kenneth P; Zhou, Feng C

2009-10-01

Alcohol exposure during development can cause variable neurofacial deficit and growth retardation known as fetal alcohol spectrum disorders (FASD). The mechanism underlying FASD is not fully understood. However, alcohol, which is known to affect methyl donor metabolism, may induce aberrant epigenetic changes contributing to FASD. Using a tightly controlled whole-embryo culture, we investigated the effect of alcohol exposure (88mM) at early embryonic neurulation on genome-wide DNA methylation and gene expression in the C57BL/6 mouse. The DNA methylation landscape around promoter CpG islands at early mouse development was analyzed using MeDIP (methylated DNA immunoprecipitation) coupled with microarray (MeDIP-chip). At early neurulation, genes associated with high CpG promoters (HCP) had a lower ratio of methylation but a greater ratio of expression. Alcohol-induced alterations in DNA methylation were observed, particularly in genes on chromosomes 7, 10, and X; remarkably, a >10 fold increase in the number of genes with increased methylation on chromosomes 10 and X was observed in alcohol-exposed embryos with a neural tube defect phenotype compared to embryos without a neural tube defect. Significant changes in methylation were seen in imprinted genes, genes known to play roles in cell cycle, growth, apoptosis, cancer, and in a large number of genes associated with olfaction. Altered methylation was associated with significant (p<0.01) changes in expression for 84 genes. Sequenom EpiTYPER DNA methylation analysis was used for validation of the MeDIP-chip data. Increased methylation of genes known to play a role in metabolism (Cyp4f13) and decreased methylation of genes associated with development (Nlgn3, Elavl2, Sox21 and Sim1), imprinting (Igf2r) and chromatin (Hist1h3d) was confirmed. In a mouse model for FASD, we show for the first time that alcohol exposure during early neurulation can induce aberrant changes in DNA methylation patterns with associated changes in

Spontaneous generalization of abstract multimodal patterns in young domestic chicks.

PubMed

Versace, Elisabetta; Spierings, Michelle J; Caffini, Matteo; Ten Cate, Carel; Vallortigara, Giorgio

2017-05-01

From the early stages of life, learning the regularities associated with specific objects is crucial for making sense of experiences. Through filial imprinting, young precocial birds quickly learn the features of their social partners by mere exposure. It is not clear though to what extent chicks can extract abstract patterns of the visual and acoustic stimuli present in the imprinting object, and how they combine them. To investigate this issue, we exposed chicks (Gallus gallus) to three days of visual and acoustic imprinting, using either patterns with two identical items or patterns with two different items, presented visually, acoustically or in both modalities. Next, chicks were given a choice between the familiar and the unfamiliar pattern, present in either the multimodal, visual or acoustic modality. The responses to the novel stimuli were affected by their imprinting experience, and the effect was stronger for chicks imprinted with multimodal patterns than for the other groups. Interestingly, males and females adopted a different strategy, with males more attracted by unfamiliar patterns and females more attracted by familiar patterns. Our data show that chicks can generalize abstract patterns by mere exposure through filial imprinting and that multimodal stimulation is more effective than unimodal stimulation for pattern learning.

Blood flow velocity measurements in chicken embryo vascular network via PIV approach

NASA Astrophysics Data System (ADS)

Kurochkin, Maxim A.; Stiukhina, Elena S.; Fedosov, Ivan V.; Tuchin, Valery V.

2018-04-01

A method for measuring of blood velocity in the native vasculature of a chick embryo by the method of micro anemometry from particle images (μPIV) is improved. A method for interrogation regions sorting by the mask of the vasculature is proposed. A method for sorting of the velocity field of capillary blood flow is implemented. The in vitro method was evaluated for accuracy in a glass phantom of a blood vessel with a diameter of 50 μm and in vivo on the bloodstream of a chicken embryo, by comparing the transverse profile of the blood velocity obtained by the PIV method with the theoretical Poiseuille laminar flow profile.

Gc protein-derived macrophage-activating factor (GcMAF) stimulates cAMP formation in human mononuclear cells and inhibits angiogenesis in chick embryo chorionallantoic membrane assay.

PubMed

Pacini, Stefania; Morucci, Gabriele; Punzi, Tiziana; Gulisano, Massimo; Ruggiero, Marco

2011-04-01

The effects of Gc protein-derived macrophage-activating factor (GcMAF) have been studied in cancer and other conditions where angiogenesis is deregulated. In this study, we demonstrate for the first time that the mitogenic response of human peripheral blood mononuclear cells (PBMCs) to GcMAF was associated with 3'-5'-cyclic adenosine monophosphate (cAMP) formation. The effect was dose dependent, and maximal stimulation was achieved using 0.1 ng/ml. Heparin inhibited the stimulatory effect of GcMAF on PBMCs. In addition, we demonstrate that GcMAF (1 ng/ml) inhibited prostaglandin E(1)- and human breast cancer cell-stimulated angiogenesis in chick embryo chorionallantoic membrane (CAM) assay. Finally, we tested different GcMAF preparations on CAM, and the assay proved to be a reliable, reproducible and inexpensive method to determine the relative potencies of different preparations and their stability; we observed that storage at room temperature for 15 days decreased GcMAF potency by about 50%. These data could prove useful for upcoming clinical trials on GcMAF.

Early maternal serum ß-human chorionic gonadotropin (ß-hCG) levels and sex-related growth difference of IVF embryos.

PubMed

Esh-Broder, Efrat; Oron, Galia; Son, Weon-Young; Holzer, Hananel; Tulandi, Togas

2015-10-01

Maternal serum ß-human chorionic gonadotropin (ß-hCG) represents the trophoblastic cell mass and is an indirect measurement of embryo development at early implantation stage. Studies in animals and human embryos detected sex-related growth differences (SRGD) in favour of male embryos during the pre-implantation period. The purpose of our study was to correlate SRGD and maternal serum ß-hCG at 16 days after embryo transfer. We retrospectively analysed all (fresh and frozen) non-donor, single embryo transfers (SET), elective and not elective, that were performed between December 2008 and December 2013. We included ß-hCG values from day 16 after oocyte collection of pregnancies resulting in live birth. Neonatal gender was retrieved from patient files. Male and female embryos were further grouped to cleavage and blastocyst stage transfers. Regression analysis for confounding variables included maternal age, maternal body mass index (BMI), use of micromanipulation (ICSI), embryo quality (grade), assisted hatching, day of transfer and fresh or frozen embryo transfer. Seven hundred eighty-six non-donor SETs resulted in live birth. After including only day 16 serum ß-hCG results, 525 SETs were analysed. Neonatal gender was available for 522 cases. Mean maternal serum ß-hCG levels were similar, 347 ± 191 IU/L in the male newborn group and 371 ± 200 IU/L in the female group. The difference between ß-hCG levels remained insignificant after adjusting for confounding variables. Early maternal ß-hCG levels after embryo transfers did not represent SRGD in our study.

9 CFR 113.31 - Detection of avian lymphoid leukosis.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., shall be done in chick embryo cell cultures. (1) Each vaccine virus, cytopathic to chick embryo...) Uninoculated chick embryo fibroblast cell cultures shall act as negative controls. One set of chick fibroblast...

9 CFR 113.31 - Detection of avian lymphoid leukosis.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., shall be done in chick embryo cell cultures. (1) Each vaccine virus, cytopathic to chick embryo...) Uninoculated chick embryo fibroblast cell cultures shall act as negative controls. One set of chick fibroblast...

9 CFR 113.31 - Detection of avian lymphoid leukosis.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., shall be done in chick embryo cell cultures. (1) Each vaccine virus, cytopathic to chick embryo...) Uninoculated chick embryo fibroblast cell cultures shall act as negative controls. One set of chick fibroblast...

9 CFR 113.31 - Detection of avian lymphoid leukosis.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., shall be done in chick embryo cell cultures. (1) Each vaccine virus, cytopathic to chick embryo...) Uninoculated chick embryo fibroblast cell cultures shall act as negative controls. One set of chick fibroblast...

Identification, emergence and mobilization of circulating endothelial cells or progenitors in the embryo.

PubMed

Pardanaud, Luc; Eichmann, Anne

2006-07-01

Using quail-chick parabiosis and QH1 monoclonal antibody analysis, we have identified circulating endothelial cells and/or progenitors in the embryo. These cells were already present early in ontogeny, before the third embryonic day. Under normal conditions, they integrated into most tissues but remained scarce. When experimental angiogenic responses were induced by wounding or grafts onto the chorioallantoic membrane, circulating endothelial cells were rapidly mobilized and selectively integrated sites of neoangiogenesis. Their mobilization was not dependent on the presence of the bone marrow as it was effective before its differentiation. Surprisingly, mobilization was not effective during sprouting angiogenesis following VEGF treatment of chorioallantoic membrane. Thus, embryonic circulating endothelial cells were efficiently mobilized during the establishment of an initial vascular supply to ischemic tissues following wounding or grafting, but were not involved during classical sprouting angiogenesis.

Rapid Induction of Apoptosis in Gastrulating Mouse Embryos by Ethanol and Its Prevention by HB-EGF

PubMed Central

Kilburn, Brian A.; Chiang, Po Jen; Wang, Jun; Flentke, George R.; Smith, Susan M.; Armant, D. Randall

2006-01-01

Background Ethanol exposure during gastrulation and early neurulation induces apoptosis within certain embryonic cell populations, leading to craniofacial and neurological defects. There is currently little information about the initial kinetics of ethanol-induced apoptosis, and interest in the ability of endogenous survival factors to moderate apoptosis is growing. Ethanol alters intracellular signaling, leading to cell death in chick embryos, suggesting that apoptosis could occur rapidly and that signaling pathways activated by survival factors might reduce apoptosis. Methods Pregnant mice were intubated with 1, 2, or 4 g/kg ethanol on day 7.5 of embryogenesis (E7.5) 1, 3, or 6, hours before harvesting gastrulation-stage embryos. Control animals received maltose/dextran. Blood alcohol concentrations (BAC) were determined by gas chromatography. E7.5 embryos isolated from untreated dams were cultured in vitro for 1 or 3 hr with 0 or 400 mg% ethanol and 0 or 5 nM heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF). Apoptosis was quantified using fluorescence microscopy to detect annexin V binding and DNA fragmentation [terminal deoxynucleotidyl transferase-mediated dUTP-X nick end labeling (TUNEL)] in whole-mount or sectioned embryos. Results Both annexin V binding and TUNEL were elevated (p<0.05) in embryos exposed in utero to 1 g/kg ethanol for 3 hours, increasing linearly with time and ethanol concentration. Apoptosis increased (p<0.05) in all germ cell layers. Mice treated with 4 g/kg sustained BAC of 400 mg% for nearly 3 hours, significantly increasing apoptosis within the first hour. Cultured embryos exposed to 400 mg% ethanol displayed 2- to 3-fold more TUNEL than vehicle-treated embryos (p<0.05); however, exogenous HB-EGF prevented apoptosis. Conclusions Ethanol rapidly produced apoptosis in gastrulation-stage embryos, consistent with induction by intracellular signaling. The ethanol-induced apoptotic pathway was blocked by the

Increased intracellular localization of brain GLUT-1 transporter in response to ethanol during chick embryogenesis.

PubMed

Carver, F M; Shibley, I A; Miles, D S; Pennington, J S; Pennington, S N

1999-10-01

Fetal exposure to ethanol is associated with growth retardation of the developing central nervous system. We have previously described a chick model to study the molecular mechanism of ethanol effects on glucose metabolism in ovo. Total membrane fractions were prepared from day 4, day 5, and day 7 chick embryos exposed in ovo to ethanol or to vehicle. By Western blotting analysis, ethanol exposure caused a mean 7- to 10-fold increase in total GLUT-1 and a 2-fold increase in total GLUT-3. However, glucose uptake by ethanol-treated cells increased by only 10%. Analysis of isolated plasma (PM) and intracellular (IM) membranes from day 5 cranial tissue revealed a mean 25% decrease in GLUT-1 in the PM and a 66% increase in the IM in the ethanol group vs. control. The amount of PM GLUT-3 was unchanged but that of IM GLUT-3 was significantly decreased. The data suggest that GLUT-3 cell surface expression may be resistant to the suppressive effects of ethanol in the developing brain of ethanol-treated embryos. The overall increase in GLUT-1 may reflect a deregulation of the transporter induced by ethanol exposure. The increased IM localization and decreased amount of PM GLUT-1 may be a mechanism used by the ethanol-treated cell to maintain normal glucose uptake despite the overall increased level of the transporter.

Dissection and Downstream Analysis of Zebra Finch Embryos at Early Stages of Development

PubMed Central

Murray, Jessica R.; Stanciauskas, Monika E.; Aralere, Tejas S.; Saha, Margaret S.

2014-01-01

The zebra finch (Taeniopygiaguttata) has become an increasingly important model organism in many areas of research including toxicology1,2, behavior3, and memory and learning4,5,6. As the only songbird with a sequenced genome, the zebra finch has great potential for use in developmental studies; however, the early stages of zebra finch development have not been well studied. Lack of research in zebra finch development can be attributed to the difficulty of dissecting the small egg and embryo. The following dissection method minimizes embryonic tissue damage, which allows for investigation of morphology and gene expression at all stages of embryonic development. This permits both bright field and fluorescence quality imaging of embryos, use in molecular procedures such as in situ hybridization (ISH), cell proliferation assays, and RNA extraction for quantitative assays such as quantitative real-time PCR (qtRT-PCR). This technique allows investigators to study early stages of development that were previously difficult to access. PMID:24999108

Localization of basic fibroblast growth factor binding sites in the chick embryonic neural retina.

PubMed

Cirillo, A; Arruti, C; Courtois, Y; Jeanny, J C

1990-12-01

We have investigated the localization of basic fibroblast growth factor (bFGF) binding sites during the development of the neural retina in the chick embryo. The specificity of the affinity of bFGF for its receptors was assessed by competition experiments with unlabelled growth factor or with heparin, as well as by heparitinase treatment of the samples. Two different types of binding sites were observed in the neural retina by light-microscopic autoradiography. The first type, localized mainly to basement membranes, was highly sensitive to heparitinase digestion and to competition with heparin. It was not developmentally regulated. The second type of binding site, resistant to heparin competition, appeared to be associated with retinal cells from the earliest stages studied (3-day-old embryo, stages 21-22 of Hamburger and Hamilton). Its distribution was found to vary during embryonic development, paralleling layering of the neural retina. Binding of bFGF to the latter sites was observed throughout the retinal neuroepithelium at early stages but displayed a distinct pattern at the time when the inner and outer plexiform layers were formed. During the development of the inner plexiform layer, a banded pattern of bFGF binding was observed. These bands, lying parallel to the vitreal surface, seemed to codistribute with the synaptic bands existing in the inner plexiform layer. The presence of intra-retinal bFGF binding sites whose distribution varies with embryonic development suggests a regulatory mechanism involving differential actions of bFGF on neural retinal cells.

Disparities in reproductive outcomes according to the endometrial preparation protocol in frozen embryo transfer : The risk of early pregnancy loss in frozen embryo transfer cycles.

PubMed

Hatoum, I; Bellon, L; Swierkowski, N; Ouazana, M; Bouba, S; Fathallah, K; Paillusson, B; Bailly, M; Boitrelle, F; Alter, L; Bergère, M; Selva, J; Wainer, R

2018-03-01

The purpose of this study was to determine the effect of stimulated and artificial endometrial preparation protocols on reproductive outcomes in frozen embryo transfer (FET) cycles. We performed a retrospective study of 1926 FET cycles over a 3.5-year period in the Fertility Unit at a University Hospital. Stimulated and artificial protocols were used for endometrial preparation. The embryos for FET were obtained from either in vitro fertilization or intracytoplasmic sperm injection cycles. Live birth rate and early pregnancy loss rates were retrospectively compared. In artificial protocols, oral or vaginal administration of oestradiol 2 mg two or three times a day was followed by vaginal supplementation with progesterone 200 mg two or three times a day. In stimulated protocols, recombinant follicle-stimulating hormone was administered from day 4 onward. Vaginal ultrasound was used for endometrial and ovarian monitoring. A pregnancy test was performed 14 days after FET. If it was positive, oestradiol and progesterone were administered up until the 12th week of gestation in artificial cycles. We defined early pregnancy losses as biochemical pregnancies (preclinical losses) and miscarriages. Data on 865 artificial cycles (45% of the total) and 1061 stimulated cycles (55%) were collected. Early pregnancy loss rate was significantly lower for stimulated cycles (34.2%) than for artificial cycles (56.9%), and the live birth rate was significantly higher for stimulated cycles (59.7%) than for artificial cycles (29.1%). In frozen embryo transfer, artificial cycles were associated with more early pregnancy loss and lower live birth rate than stimulated cycles.

Limb movements during embryonic development in the chick: evidence for a continuum in limb motor control antecedent to locomotion.

PubMed

Bradley, Nina S; Solanki, Dhara; Zhao, Dawn

2005-12-01

New imaging technologies are revealing ever-greater details of motor behavior in fetuses for clinical diagnosis and treatment. Understanding the form, mechanisms, and significance of fetal behavior will maximize imaging applications. The chick is readily available for experimentation throughout embryogenesis, making it an excellent model for this purpose. Yet in 40 yr since Hamburger and colleagues described chick embryonic behavior, we have not determined if motility belongs to a developmental continuum fundamental to posthatching behavior. This study examined kinematics and synchronized electromyography (EMG) during spontaneous limb movements in chicks at four time points between embryonic days (E) 9-18. We report that coordinated kinematic and/or EMG patterns were expressed at each time point. Variability observed in knee and ankle excursions at E15-E18 sorted into distinct in-phase and out-of-phase patterns. EMG patterns did not directly account for out-of-phase patterns, indicating study of movement biomechanics will be critical to fully understand motor control in the embryo. We also provide the first descriptions of 2- to 10-Hz limb movements emerging E15-E18 and a shift from in-phase to out-of-phase interlimb coordination E9-E18. Our findings revealed that coordinated limb movements persist across development and suggest they belong to a developmental continuum for locomotion. Limb patterns were consistent with the half center model for a locomotor pattern generator. Achievement of these patterns by E9 may thus indicate the embryo has completed a critical phase beyond which developmental progression may be less vulnerable to experimental perturbations or prenatal events.

The early Cambrian fossil embryo Pseudooides is a direct-developing cnidarian, not an early ecdysozoan.

PubMed

Duan, Baichuan; Dong, Xi-Ping; Porras, Luis; Vargas, Kelly; Cunningham, John A; Donoghue, Philip C J

2017-12-20

Early Cambrian Pseudooides prima has been described from embryonic and post-embryonic stages of development, exhibiting long germ-band development. There has been some debate about the pattern of segmentation, but this interpretation, as among the earliest records of ecdysozoans, has been generally accepted. Here, we show that the 'germ band' of P. prima embryos separates along its mid axis during development, with the transverse furrows between the 'somites' unfolding into the polar aperture of the ten-sided theca of Hexaconularia sichuanensis , conventionally interpreted as a scyphozoan cnidarian; co-occurring post-embryonic remains of ecdysozoans are unrelated. We recognize H. sichuanensis as a junior synonym of P. prima as a consequence of identifying these two form-taxa as distinct developmental stages of the same organism. Direct development in P. prima parallels the co-occuring olivooids Olivooides, and Quadrapyrgites and Bayesian phylogenetic analysis of a novel phenotype dataset indicates that, despite differences in their tetra-, penta- and pseudo-hexa-radial symmetry, these hexangulaconulariids comprise a clade of scyphozoan medusozoans, with Arthrochites and conulariids, that all exhibit direct development from embryo to thecate polyp. The affinity of hexangulaconulariids and olivooids to extant scyphozoan medusozoans indicates that the prevalence of tetraradial symmetry and indirect development are a vestige of a broader spectrum of body-plan symmetries and developmental modes that was manifest in their early Phanerozoic counterparts. © 2017 The Authors.

The early Cambrian fossil embryo Pseudooides is a direct-developing cnidarian, not an early ecdysozoan

PubMed Central

2017-01-01

Early Cambrian Pseudooides prima has been described from embryonic and post-embryonic stages of development, exhibiting long germ-band development. There has been some debate about the pattern of segmentation, but this interpretation, as among the earliest records of ecdysozoans, has been generally accepted. Here, we show that the ‘germ band’ of P. prima embryos separates along its mid axis during development, with the transverse furrows between the ‘somites’ unfolding into the polar aperture of the ten-sided theca of Hexaconularia sichuanensis, conventionally interpreted as a scyphozoan cnidarian; co-occurring post-embryonic remains of ecdysozoans are unrelated. We recognize H. sichuanensis as a junior synonym of P. prima as a consequence of identifying these two form-taxa as distinct developmental stages of the same organism. Direct development in P. prima parallels the co-occuring olivooids Olivooides, and Quadrapyrgites and Bayesian phylogenetic analysis of a novel phenotype dataset indicates that, despite differences in their tetra-, penta- and pseudo-hexa-radial symmetry, these hexangulaconulariids comprise a clade of scyphozoan medusozoans, with Arthrochites and conulariids, that all exhibit direct development from embryo to thecate polyp. The affinity of hexangulaconulariids and olivooids to extant scyphozoan medusozoans indicates that the prevalence of tetraradial symmetry and indirect development are a vestige of a broader spectrum of body-plan symmetries and developmental modes that was manifest in their early Phanerozoic counterparts. PMID:29237861

Early developmental gene regulation in Strongylocentrotus purpuratus embryos in response to elevated CO₂ seawater conditions.

PubMed

Hammond, LaTisha M; Hofmann, Gretchen E

2012-07-15

Ocean acidification, or the increased uptake of CO(2) by the ocean due to elevated atmospheric CO(2) concentrations, may variably impact marine early life history stages, as they may be especially susceptible to changes in ocean chemistry. Investigating the regulatory mechanisms of early development in an environmental context, or ecological development, will contribute to increased understanding of potential organismal responses to such rapid, large-scale environmental changes. We examined transcript-level responses to elevated seawater CO(2) during gastrulation and the initiation of spiculogenesis, two crucial developmental processes in the purple sea urchin, Strongylocentrotus purpuratus. Embryos were reared at the current, accepted oceanic CO(2) concentration of 380 microatmospheres (μatm), and at the elevated levels of 1000 and 1350 μatm, simulating predictions for oceans and upwelling regions, respectively. The seven genes of interest comprised a subset of pathways in the primary mesenchyme cell gene regulatory network (PMC GRN) shown to be necessary for the regulation and execution of gastrulation and spiculogenesis. Of the seven genes, qPCR analysis indicated that elevated CO(2) concentrations only had a significant but subtle effect on two genes, one important for early embryo patterning, Wnt8, and the other an integral component in spiculogenesis and biomineralization, SM30b. Protein levels of another spicule matrix component, SM50, demonstrated significant variable responses to elevated CO(2). These data link the regulation of crucial early developmental processes with the environment that these embryos would be developing within, situating the study of organismal responses to ocean acidification in a developmental context.

No significant regulation of bicoid mRNA by Pumilio or Nanos in the early Drosophila embryo.

PubMed

Wharton, Tammy H; Nomie, Krystle J; Wharton, Robin P

2018-01-01

Drosophila Pumilio (Pum) is a founding member of the conserved Puf domain class of RNA-binding translational regulators. Pum binds with high specificity, contacting eight nucleotides, one with each of the repeats in its RNA-binding domain. In general, Pum is thought to block translation in collaboration with Nanos (Nos), which exhibits no binding specificity in isolation but is recruited jointly to regulatory sequences containing a Pum binding site in the 3'-UTRs of target mRNAs. Unlike Pum, which is ubiquitous in the early embryo, Nos is tightly restricted to the posterior, ensuring that repression of its best-characterized target, maternal hunchback (hb) mRNA, takes place exclusively in the posterior. An exceptional case of Nos-independent regulation by Pum has been described-repression of maternal bicoid (bcd) mRNA at the anterior pole of the early embryo, dependent on both Pum and conserved Pum binding sites in the 3'-UTR of the mRNA. We have re-investigated regulation of bcd in the early embryo; our experiments reveal no evidence of a role for Pum or its conserved binding sites in regulation of the perdurance of bcd mRNA or protein. Instead, we find that Pum and Nos control the accumulation of bcd mRNA in testes.

Studies on trypsin-like enzymes in sperm and early embryos

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

Penn, A.

1975-12-09

Results are reported from a study of acrosomal proteinase, a trypsin-like enzyme (TLE), found in the acrosome of all eutherian mammals studied to date. It has been implicated in the dissolution of a passage for the sperm through the zona pellucida of the egg, a step necessary for in vivo fertilization. A cytochemical procedure employing autoradiographic film as a gelatin substrate is described for in situ detection and localization of acrosomal proteolytic activity. A role for TLE in the early development of embryos is suggested. (CH)

Differential Expression of Metallothionein Isoforms in Terrestrial Snail Embryos Reflects Early Life Stage Adaptation to Metal Stress

PubMed Central

Baurand, Pierre-Emmanuel; Pedrini-Martha, Veronika; de Vaufleury, Annette; Niederwanger, Michael; Capelli, Nicolas; Scheifler, Renaud; Dallinger, Reinhard

2015-01-01

The aim of this study was to analyze the expression of three metallothionein (MT) isoform genes (CdMT, CuMT and Cd/CuMT), already known from adults, in the Early Life Stage (ELS) of Cantareus aspersus. This was accomplished by detection of the MT isoform-specific transcription adopting Polymerase Chain Reaction (PCR) amplification and quantitative Real Time (qRT)-PCR of the three MT genes. Freshly laid eggs were kept for 24 hours under control conditions or exposed to three cadmium (Cd) solutions of increasing concentration (5, 10, and 15 mg Cd/L). The transcription of the three MT isoform genes was detected via PCR in 1, 6 and 12-day-old control or Cd-exposed embryos. Moreover, the transcription of this isoform genes during development was followed by qRT-PCR in 6 and 12-day-old embryos. Our results showed that the CdMT and Cd/CuMT genes, but not the CuMT gene, are expressed in embryos at the first day of development. The transcription of the 3 MT genes in control embryos increased with development time, suggesting that the capacities of metal regulation and detoxification may have gradually increased throughout embryogenesis. However in control embryos, the most highly expressed MT gene was that of the Cd/CuMT isoform, whose transcription levels greatly exceeded those of the other two MT genes. This contrasts with the minor significance of this gene in adult snails and suggests that in embryos, this isoform may play a comparatively more important role in metal physiology compared to adult individuals. This function in adult snails appears not to be related to Cd detoxification. Instead, snail embryos responded to Cd exposure by over-expression of the CdMT gene in a concentration-dependent manner, whereas the expression of the Cd/CuMT gene remained unaffected. Moreover, our study demonstrates the ability of snail embryos to respond very early to Cd exposure by up-regulation of the CdMT gene. PMID:25706953

Effects of mixing eggs of different initial incubation time on the hatching pattern, chick embryonic development and post-hatch performance.

PubMed

Zhong, Zhentao; Yu, Yue; Jin, Shufang; Pan, Jinming

2018-01-01

The hatch window that varies from 24 to 48 h is known to influence post-hatch performance of chicks. A narrow hatch window is needed for commercial poultry industry to acquire a high level of uniformity of chick quality. Hatching synchronization observed in avian species presents possibilities in altering hatch window in artificial incubation. Layer eggs which were laid on the same day by a single breeder flock and stored for no more than two days started incubation 12 h apart to obtain developmental distinction. The eggs of different initial incubation time were mixed as rows adjacent to rows on day 12 of incubation. During the hatching period (since day 18), hatching time of individual eggs and hatch window were obtained by video recordings. Embryonic development (day 18 and 20) and post-hatch performance up to day 7 were measured. The manipulation of mixing eggs of different initial incubation time shortened the hatch window of late incubated eggs in the manipulated group by delaying the onset of hatching process, and improved the hatchability. Compared to the control groups, chick embryos or chicks in the egg redistribution group showed no significant difference in embryonic development and post-hatch performance up to day 7. We have demonstrated that eggs that were incubated with advanced eggs performed a narrow spread of hatch with higher hatchability, normal embryonic development as well as unaffected chick quality. This specific manipulation is applicable in industrial poultry production to shorten hatch window and improve the uniformity of chick quality.

Gastrointestinal obstruction in penguin chicks.

PubMed

Perpiñán, David; Curro, Thomas G

2009-12-01

A 7-day-old gentoo penguin (Pygoscelis papua) was found dead and postmortem examination revealed impaction of the ventriculus with feathers. A review of mortality in gentoo penguin chicks from 1997 to 2007 at that institution revealed another case of feather impaction of the ventriculus in a 4-week-old chick, a sibling of the previous chick. A third case of gastrointestinal impaction occurred in a 24-day-old king penguin (Aptenodytes patagonicus) with omphallitis and enteritis. In this chick, a fibrin mat produced a complete obstruction of the intestine at the level of Meckel's diverticulum.

The First Human Cloned Embryo.

ERIC Educational Resources Information Center

Cibelli, Jose B.; Lanza, Robert P.; West, Michael D.; Ezzell, Carol

2002-01-01

Describes a process known as parthenogenesis which produces cloned, early-stage embryos and human embryos generated only from eggs. Speculates that this technology puts therapeutic cloning within reach. (DDR)

Notch and Delta mRNAs in early-stage and mid-stage Drosophila embryos exhibit complementary patterns of protein producing potentials

PubMed Central

Shepherd, Andrew; Wesley, Uma; Wesley, Cedric

2010-01-01

Notch and Delta proteins generate Notch signaling that specifies cell fates during animal development. There is an intriguing phenomenon in Drosophila embryogenesis that has not received much attention and whose significance to embryogenesis is unknown. Notch and Delta mRNAs expressed in early-stage embryos are shorter than their counterparts in mid-stage embryos. We show here that the difference in sizes is due to mRNA 3′ processing at alternate polyadenylation sites. While the early-stage Notch mRNA has a lower protein-producing potential than the mid-stage Notch mRNA, the early-stage Delta mRNA has a higher protein-producing potential than the mid-stage Delta mRNA. Our data can explain the complementary patterns of Notch and Delta protein levels in early-stage and mid-stage embryos. Our data also raise the possibility that the manner and regulation of Notch signaling change in the course of embryogenesis and that this change is effected by 3′ UTR and mRNA 3′ processing factors. PMID:20201103

Early embryo development in Fucus distichus is auxin sensitive

NASA Technical Reports Server (NTRS)

Basu, Swati; Sun, Haiguo; Brian, Leigh; Quatrano, Ralph L.; Muday, Gloria K.

2002-01-01

Auxin and polar auxin transport have been implicated in controlling embryo development in land plants. The goal of these studies was to determine if auxin and auxin transport are also important during the earliest stages of development in embryos of the brown alga Fucus distichus. Indole-3-acetic acid (IAA) was identified in F. distichus embryos and mature tissues by gas chromatography-mass spectroscopy. F. distichus embryos accumulate [(3)H]IAA and an inhibitor of IAA efflux, naphthylphthalamic acid (NPA), elevates IAA accumulation, suggesting the presence of an auxin efflux protein complex similar to that found in land plants. F. distichus embryos normally develop with a single unbranched rhizoid, but growth on IAA leads to formation of multiple rhizoids and growth on NPA leads to formation of embryos with branched rhizoids, at concentrations that are active in auxin accumulation assays. The effects of IAA and NPA are complete before 6 h after fertilization (AF), which is before rhizoid germination and cell division. The maximal effects of IAA and NPA are between 3.5 and 5 h AF and 4 and 5.5 h AF, respectively. Although, the location of the planes of cell division was significantly altered in NPA- and IAA-treated embryos, these abnormal divisions occurred after abnormal rhizoid initiation and branching was observed. The results of this study suggest that auxin acts in the formation of apical basal patterns in F. distichus embryo development.

Differences in egg nutrient availability and embryo development in white layer breeder genotypes.

PubMed

Onbasilar, E E; Kahraman, M; Ahlat, O; Güngör, Ö F; Çalik, A; Taban, S; Yalçin, S

2017-10-01

Because of consumers' preferences and also due to changes in production systems, the importance of pure breeds has increased again. There are a lot of differences among breeds which have been studied extensively, however, the differences during the incubation period are not yet fully known. Therefore, the present study was conducted to evaluate the composition of the egg parts, absorption of nutrients, and development of embryos from different genotypes. A total of 354 fresh hatching eggs were obtained from one hybrid (Lohman White, LW) and two pure breeds (Denizli and Gerze). Hatching eggs from each genotype were examined on the day of setting for egg analysis and then at the beginning of the embryonic d 19 (E19) and embryonic d 21 (E21) for egg, embryo, jejunum, and tibia analysis. On d 21 of incubation, the healthy chicks were removed and weighed. Egg weight, shell thickness, percentages of albumen, and some parameters of albumen composition (dry matter, water, ash, protein, energy, Na, Ca, K, and Mg) were higher in fresh eggs obtained from LW hens. Furthermore, the relative yolk sac and embryo weight, some yolk parameters (dry matter, water, protein, fat, and energy) and some shell parameters (dry matter, ash, Na, Ca, and K) were also higher in eggs obtained from LW hens during incubation. However, tibia deformation and villus width were lower in LW embryos than the other genotypes. Relative chick weights were 68.9, 72.0, and 68.0% in LW, Denizli, and Gerze genotypes, respectively. During incubation, differences in all examined parameters were significant except thickness and weight of shell, tibia deformation, and crypt depth. Yolk sac weight, some yolk composition parameters, K level in the shell, Cu level in the tibia, and villus height were also affected by genotype and period interaction. Based on these results, LW was found advantageous in terms of egg composition, however, regarding villus development and tibia deformation in embryos during incubation

Redundant roles of Sox17 and Sox18 in early cardiovascular development of mouse embryos

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

Sakamoto, Youhei; Hara, Kenshiro; Kanai-Azuma, Masami

Sox7, -17 and -18 constitute the Sox subgroup F (SoxF) of HMG box transcription factor genes, which all are co-expressed in developing vascular endothelial cells in mice. Here we characterized cardiovascular phenotypes of Sox17/Sox18-double and Sox17-single null embryos during early-somite stages. Whole-mount PECAM staining demonstrated the aberrant heart looping, enlarged cardinal vein and mild defects in anterior dorsal aorta formation in Sox17 single-null embryos. The Sox17/Sox18 double-null embryos showed more severe defects in formation of anterior dorsal aorta and head/cervical microvasculature, and in some cases, aberrant differentiation of endocardial cells and defective fusion of the endocardial tube. However, the posteriormore » dorsal aorta and allantoic microvasculature was properly formed in all of the Sox17/Sox18 double-null embryos. The anomalies in both anterior dorsal aorta and head/cervical vasculature corresponded with the weak Sox7 expression sites. This suggests the region-specific redundant activities of three SoxF members along the anteroposterior axis of embryonic vascular network.« less

Enc1 expression in the chick telencephalon at intermediate and late stages of development.

PubMed

García-Calero, Elena; Puelles, Luis

2009-12-10

In this work we studied the regional expression pattern of the Enc1 gene in the chick embryo telencephalon at intermediate and late stages of development, bearing on architectonic groupings and boundaries of current interest. In general, the Enc1 signal shows a markedly heterogeneous areal pattern of expression throughout the telencephalon; this corroborates data on new pallial and subpallial structures defined recently in the stereotaxic chick brain atlas of Puelles et al. (2007. The chick brain in stereotaxic coodinates. San Diego, CA: Academic Press). For example: a periventricular/central domain is Enc1-negative in the ventral pallium or nidopallium; core and shell nuclei appear in the mesopallium; the redefined caudodorsolateral area shows a characteristic pattern; the limits of the densocellular hyperpallium in the dorsal pallium are illuminated; and the postulated entorhinal cortex area is distinct at the posterior telencephalic pole. Interestingly, Enc1 transcripts are distinctly present in the piriform cortex at the surface of the ventral pallium throughout its longitudinal extent, as well as in the most rostral part of the lateral pallium, implying a layout of this cortex more similar to the situation in mammals than was assumed previously. Separate corticoid superficial strata are labeled by the Enc1 probe in the lateral and dorsal pallial regions. In the subpallium, the expression of Enc1 agrees with the new radial subdivisions defined by Puelles et al. (2007).

Dietary genistein supplementation in laying broiler breeder hens alters the development and metabolism of offspring embryos as revealed by hepatic transcriptome analysis.

PubMed

Lv, Zengpeng; Fan, Hao; Zhang, Beibei; Ning, Chao; Xing, Kun; Guo, Yuming

2018-03-08

Genistein (GEN) is a type of isoflavone mainly derived from soy products. In this experiment, we added 40 and 400 mg/kg GEN to the diet of laying broiler breeder hens to clarify the maternal effects of GEN on the development and metabolism of chick embryos. GEN treatment at 40 mg/kg increased embryonic length, weight, and liver index, as well as the width of the proliferative zone in the tibial growth plate of chick embryos. Gene ontology (GO) cluster analysis of the hepatic transcriptome showed that GEN treatment promoted embryonic development and cell proliferation. Low-dose GEN treatment increased insulin growth factor-binding protein (IGFBP)3 mRNA expression in the embryonic liver, whereas high-dose GEN treatment increased IGFBP5 expression and activated the apoptosis and protein tyrosine kinase signaling pathways. Furthermore, adding supplemental GEN to the diet of hens promoted the glycolysis process in the embryonic liver through the insulin-signaling pathway, upregulated target genes (phosphoglucomutase-2, hexokinase 1, dihydroxyacetone phosphate by aldolase, phosphofructokinase, platelet, and enolase 2), and enhanced the transport of carboxylic acids and cholesterol and the synthesis of unsaturated fatty acid (arachidonic acid) in the embryonic liver through upregulation of liver X receptor, sterol regulatory element-binding protein 1, and patatin-like phospholipase A. Additionally, GEN treatment increased fatty acid β-oxidation and Na + /K + -ATPase activity in the embryonic liver through activation of peroxisome proliferator-activated receptors (PPARs; PPARα and PPARδ) and the AMPK signaling pathway, which could provide energy for embryonic development. In addition, GEN treatment in hens increased superoxide dismutase activity and metallothionein expression in the chick embryonic liver and promoted lymphocyte proliferation through upregulation of mRNA expression of CDKN1A, IL12RB1, Sox11, PRKAR1A, PRKCQ, and TCF3. The improved immunity and antioxidant

Culture of domestic cat ovarian tissue in vitro and in the chick embryo chorioallantoic membrane.

PubMed

Vilela, J M V; Leonel, E C R; D'Oliveira, L; Paiva, R E G; Miranda-Vilela, A L; Amorim, C A; Pic-Taylor, A; Lucci, C M

2016-10-15

In vitro culture and transplantation procedures are essential protocols employed in the evaluation of ovarian follicle survival and development. Culture in the chorioallantoic membrane (CAM) of chick embryos is an intermediate method that provides important follicle development information and has not been tested for cat ovaries to date. The aim of this study was to investigate if in vitro and CAM culture could be used as short-term systems to study cat ovarian tissue development. The ovaries of eight cats were dissected into 3-mm(3) cubes, cultured in vitro and in CAM for up to 5 days, and stained with hematoxylin-eosin and Gomori trichrome. Cell proliferation was analyzed using anti-Ki67. Possible differences among groups were investigated by analysis of variance or the Kruskal-Wallis test followed by Bonferroni correction. The T-test or Wilcoxon test was used to verify differences between the CAM and IVC. Results revealed that 87.5% of all follicles were primordial during culture. The percentage of primordial follicles in the morphologically normal follicles (MNF) pool was always higher than 80%, with the exception of Day 3 of CAM culture, but the number of MNF reduced significantly from Day 0 (600 out of 777 follicles) to Day 5 in the CAM (91 out of 171) and IVC (296 out of 686). The number of primordial follicles in 1 mm(3) in Days 2, 3, and 5 in the CAM was significantly lower than that in the control (Day 0). No cellular proliferation was observed in culture. Vascularization occurred in the CAM culture, but with no association to follicular viability. In addition, both methods showed an increase in connective tissue during culture. Although no significant differences were observed in the percentage of MNF, there was a reduction in the total number of follicles, both for IVC and CAM-cultured ovarian tissue. Furthermore, anti-Ki67 did not stain any follicle after Day 0 in IVC or in CAM culture. Neither system was capable of promoting follicle growth and

Role of the phagocytes on embryos: some morphological aspects.

PubMed

Da Silva, José Roberto Machado Cunha

2002-06-15

Phagocytosis in embryos was studied by Elie Metchnikoff more than a century ago and is a pillar of the Phagocytic Theory. Throughout the last three decades phagocytosis in embryos has been studied from different perspectives, which this review describes and analyzes. The following branches were identified: 1) the search for the origin and first identification of well-known adult phagocytes in embryos, including their role after induced injuries; 2) the search for the occurrence of phagocytosis in embryos and its role during their physiological development; and 3) the search for phagocytosis in embryos, as a tool to study identity and self-recognition. It is possible to verify that different cell types are able to undertake phagocytosis, under a variety of different stimuli, and that the nature of what is phagocytosed also varies widely. Although the overwhelming majority of species described among metazoarians are invertebrates, most published articles in this field relate to mammals (particularly mice and humans) and birds (particularly chicks). In order to enrich this field of knowledge, research using a wider variety of vertebrate and invertebrate species should be undertaken. Furthermore, the present knowledge of phagocytosis in embryos needs a revised paradigm capable of embracing all the above-mentioned research trends under a single, more general, biological theory. In this sense, Metchnikoff's Phagocytic Theory, which is based on a broad biological paradigm and is thus capable of dealing with all research trends mentioned herein, should be revisited in order to contribute to this edification. Copyright 2002 Wiley-Liss, Inc.

Quantitative Analysis of the Area of the Apical Ectodermal Ridge in Chick Appendages Using Image-J.

PubMed

Syed, Hamd Binte Shahab; Khan, Muhammad Yunus

2018-06-01

To determine the effect of sodium phenytoin on the apical ectodermal ridges (AER) of chick wing buds by using the software program Image-J. An experimental study. Department of Anatomy, Regional Center, College of Physicians and Surgeons Pakistan (CPSP), Islamabad, from January 2014 to January 2015. Sixty fertilised chicken eggs of 'Egyptian fayoumi' breed were selected and separated into experimental (B) and control (A) groups, each having 30 eggs. A single dose of 3.5 mg sodium phenytoin was injected into each egg of the experimental group. The controls were injected with the same volume of normal saline. Developing embryos were extracted 96 hours (day 4) after incubation and histological sections were cut at 5 μm thickness. These sections were stained with Feulgen Nuclear and Light Green. The area of apical ectodermal ridges of chick wing buds was calculated by employing Image-J and subjected to statistical analysis. The difference between the mean values of the area of apical ectodermal ridges of experimental and control groups, as calculated by Image-J, was found to be statistically insignificant. Change in the area of the apical ectodermal ridges in experimental chicks, following phenytoin exposure, was insignificant as proven on the basis of quantification by Image-J.

Global regulation of mRNA translation and stability in the early Drosophila embryo by the Smaug RNA-binding protein.

PubMed

Chen, Linan; Dumelie, Jason G; Li, Xiao; Cheng, Matthew Hk; Yang, Zhiyong; Laver, John D; Siddiqui, Najeeb U; Westwood, J Timothy; Morris, Quaid; Lipshitz, Howard D; Smibert, Craig A

2014-01-07

Smaug is an RNA-binding protein that induces the degradation and represses the translation of mRNAs in the early Drosophila embryo. Smaug has two identified direct target mRNAs that it differentially regulates: nanos and Hsp83. Smaug represses the translation of nanos mRNA but has only a modest effect on its stability, whereas it destabilizes Hsp83 mRNA but has no detectable effect on Hsp83 translation. Smaug is required to destabilize more than one thousand mRNAs in the early embryo, but whether these transcripts represent direct targets of Smaug is unclear and the extent of Smaug-mediated translational repression is unknown. To gain a panoramic view of Smaug function in the early embryo, we identified mRNAs that are bound to Smaug using RNA co-immunoprecipitation followed by hybridization to DNA microarrays. We also identified mRNAs that are translationally repressed by Smaug using polysome gradients and microarrays. Comparison of the bound mRNAs to those that are translationally repressed by Smaug and those that require Smaug for their degradation suggests that a large fraction of Smaug's target mRNAs are both translationally repressed and degraded by Smaug. Smaug directly regulates components of the TRiC/CCT chaperonin, the proteasome regulatory particle and lipid droplets, as well as many metabolic enzymes, including several glycolytic enzymes. Smaug plays a direct and global role in regulating the translation and stability of a large fraction of the mRNAs in the early Drosophila embryo, and has unanticipated functions in control of protein folding and degradation, lipid droplet function and metabolism.

Characterization of the altered gene expression profile in early porcine embryos generated from parthenogenesis and somatic cell chromatin transfer.

PubMed

Zhou, Chi; Dobrinsky, John; Tsoi, Stephen; Foxcroft, George R; Dixon, Walter T; Stothard, Paul; Verstegen, John; Dyck, Michael K

2014-01-01

The in vitro production of early porcine embryos is of particular scientific and economic interest. In general, embryos produced from in vitro Assisted Reproductive Technologies (ART) manipulations, such as somatic cell chromatin transfer (CT) and parthenogenetic activation (PA), are less developmentally competent than in vivo-derived embryos. The mechanisms underlying the deficiencies of embryos generated from PA and CT have not been completely understood. To characterize the altered genes and gene networks in embryos generated from CT and PA, comparative transcriptomic analyses of in vivo (IVV) expanded blastocysts (XB), IVV hatched blastocyst (HB), PA XB, PA HB, and CT HB were performed using a custom microarray platform enriched for genes expressed during early embryonic development. Differential expressions of 1492 and 103 genes were identified in PA and CT HB, respectively, in comparison with IVV HB. The "eIF2 signalling", "mitochondrial dysfunction", "regulation of eIF4 and p70S6K signalling", "protein ubiquitination", and "mTOR signalling" pathways were down-regulated in PA HB. Dysregulation of notch signalling-associated genes were observed in both PA and CT HB. TP53 was predicted to be activated in both PA and CT HB, as 136 and 23 regulation targets of TP53 showed significant differential expression in PA and CT HB, respectively, in comparison with IVV HB. In addition, dysregulations of several critical pluripotency, trophoblast development, and implantation-associated genes (NANOG, GATA2, KRT8, LGMN, and DPP4) were observed in PA HB during the blastocyst hatching process. The critical genes that were observed to be dysregulated in CT and PA embryos could be indicative of underlying developmental deficiencies of embryos produced from these technologies.

Individual and combined effects of in-ovo injection of creatine monohydrate and glucose on somatic characteristics, energy status, and posthatch performance of broiler embryos and hatchlings.

PubMed

Zhang, L; Zhu, X D; Wang, X F; Li, J L; Gao, F; Zhou, G H

2016-10-01

Two trials were conducted to investigate the individual and combined effects of in-ovo injection of creatine monohydrate ( CMH: ) and glucose on the somatic characteristics and energy status of broiler embryos and hatchlings and the growth performance of chicks during the first wk posthatch. In trial 1, 550 17.5-day-old living, fertile eggs were randomly assigned to 1 of 5 treatment groups, including 1) a noninjected control, 2) a 0.4 mL diluent-injected control, or 0.4 mL diluents containing 3) 6 mg CMH, 4) 25 mg glucose, or 5) a combination of 6 mg CMH and 25 mg glucose (identified as CMH+G: ). In trial 2, after hatch, 48 hatchlings with individual body weight ( BW: ) close to the average BW of their incubation group were randomly selected and placed in 6 replicates of 8 birds each to evaluate their growth performance during the first wk posthatch. Compared with the noninjected and the 0.4-mL diluent-injected control groups, individual injection of CMH or glucose did not affect the hatching time, hatchability, somatic characteristics, or concentrations of glycogen and glucose in the liver and pectoralis major ( PM: ) muscle, although injection of CMH increased (P < 0.05) concentrations of creatine ( CR: ) and phosphocreatine ( PCR: ) in the PM muscle on d 19 of incubation (E19.5). However, the CMH+G treatment increased (P < 0.05) BW relative to set egg weight ( SEW: ) on E19.5, as well as residual yolk sac weight on the day of hatch. Moreover, the CMH+G treatment also increased (P < 0.05) concentrations of glycogen and glucose in the liver and concentrations of Cr and PCr in the PM muscle on E19.5. Chicks in the CMH+G group also exhibited higher BW gain during the first wk than controls (P < 0.05). These results indicate that combined injection of CMH and glucose during the last stage of incubation have a synergistic effect on improvement of the energy status of embryos and hatchlings, which is useful for enhancing embryo development, and subsequently improving

Embryo apoptosis identification: Oocyte grade or cleavage stage?

PubMed Central

Bakri, Noraina Mohd; Ibrahim, Siti Fatimah; Osman, Nurul Atikah; Hasan, Nurhaslina; Jaffar, Farah Hanan Fathihah; Rahman, Zulaiha Abdul; Osman, Khairul

2015-01-01

Apoptosis is a programed cell death that is vital for tissue homeostasis. However, embryo apoptosis had been known to be related to embryo fragmentation which should be avoided in in vitro fertilization (IVF). The purpose of this study was to evaluate the relationship of embryo apoptosis with the grade of immature oocytes and cleavage stage of in vitro produced (IVP) cattle embryos. This study consisted of 345 oocytes collected through ovary slicing. Immature oocytes were graded as A, B and C. This grading was based on cumulus cell thickness and compactness. All oocytes then underwent an in vitro maturation (IVM) procedure. An IVF was done 24 h after IVM culture. Prior to staining, stage of cleaved embryos was determined and classified as either 2, 4, 8 or >8-cell embryo stage. Apoptosis status of cleaved IVP embryos was determined by using annexin V-FITC staining technique at 48 and 72 h post insemination (hpi). Apoptosis status for each embryo was classified as either early or late. The result showed that there was no significant difference (p > 0.05) of apoptosis status among grade A, B and C embryos. All grades of oocytes showed embryo apoptosis where 1.5% late apoptosis for grade A, 4.5% and 10.4% of early and late apoptosis for grade B and grade C. Early apoptosis was not seen in grade A embryo. We also noted no significant difference (p > 0.05) of apoptosis status between 2, 4, 8 and >8-cell embryo stage. Early apoptosis was also not seen in >8-cell stage. Even though there were no differences in apoptosis expression between the three classes, the cleavage rate of grade A oocytes was significantly higher (p < 0.01) than grade B and grade C. In conclusion, the apoptosis expression in the embryo can occur regardless of the oocyte quality and the cleavage stage of the embryo produced. PMID:26858565

Refrigeration of rainbow trout gametes and embryos.

PubMed

Babiak, Igor; Dabrowski, Konrad

2003-12-01

Prolonged access to early embryos composed of undifferentiated, totipotent blastomeres is desirable in situations when multiple collections of gametes are not possible. The objective of the present study is to examine whether the refrigeration of rainbow trout Oncorhynchus mykiss gametes and early embryos would be a suitable, reliable, and efficient tool for prolonging the availability of early developmental stages up to the advanced blastula stage. The study was conducted continuously during fall, winter, and spring spawning seasons. In all, more than 500 experimental variants were performed involving individual samples from 26 females and 33 males derived from three strains. These strains represented three possible circumstances. In optimal one, gametes from good quality donors were obtained soon after ovulation. In the two non-optimal sources, either donors were of poor genetic quality or gametes were collected from a distant location and transported as unfertilized gametes. A highly significant effect of variability of individual sample quality on efficiency of gamete and embryo refrigeration was revealed. The source of gametes significantly affected viability of refrigerated oocytes and embryos, but not spermatozoa. On average, oocytes from optimal source retained full fertilization viability for seven days of chilled storage, significantly longer than from non-optimal sources. Spermatozoa, regardless of storage method, retained full fertilization ability for the first week of storage. Refrigeration of embryos at 1.4+/-0.4 degrees C significantly slowed the development. Two- week-old embryos were still in blastula stage. Average survival rate of embryos refrigerated for 10 days and then transferred to regular incubation temperatures of 9-14 degrees C was 92% in optimal and 51 and 71% in non-optimal source variants. No effect of gamete and embryo refrigeration on the occurrence of developmental abnormalities was observed. Cumulative refrigeration of oocytes and

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.

Maternal program of apoptosis activated shortly after midblastula transition by overexpression of S-adenosylmethionine decarboxylase in Xenopus early embryos.

PubMed

Shiokawa, K; Kai, M; Higo, T; Kaito, C; Yokoska, J; Yasuhiko, Y; Kajita, E; Nagano, M; Yamada, Y; Shibata, M; Muto, T; Shinga, J; Hara, H; Takayama, E; Fukamachi, H; Yaoita, Y; Igarashi, K

2000-06-01

When we studied polyamine metabolism in Xenopus embryos, we cloned the cDNA for Xenopus S-adenosylmethionine decarboxylase (SAMDC), which converts SAM (S-adenosylmethionine), the methyl donor, into decarboxylated SAM (dcSAM), the aminopropyl donor, and microinjected its in vitro transcribed mRNA into Xenopus fertilized eggs. We found here that the mRNA injection induces a SAM deficient state in early embryos due to over-function of the overexpressed SAMDC, which in turn induces inhibition of protein synthesis. Such embryos developed quite normally until blastula stage, but stopped development at the early gastrula stage, due to induction of massive cell dissociation and cell autolysis, irrespective of the dosage and stage of the mRNA injection. We found that the dissociated cells were TUNEL-positive, contained fragmented nuclei with ladder-forming DNA, and furthermore, rescued completely by coinjection of Bcl-2 mRNA. Thus, overexpression of SAMDC in Xenopus embryos appeared to switch on apoptotic program, probably via inhibition of protein synthesis. Here, we briefly review our results together with those reported from other laboratories. After discussing the general importance of this newly discovered apoptotic program, we propose that the maternal program of apoptosis serves as a surveillance mechanism to eliminate metabolically severely-damaged cells and functions as a 'fail-safe' mechanism for normal development in Xenopus embryos.

Overexpression of S-adenosylmethionine decarboxylase (SAMDC) in early Xenopus embryos induces cell dissociation and inhibits transition from the blastula to gastrula stage.

PubMed

Shibata, M; Shinga, J; Yasuhiko, Y; Kai, M; Miura, K; Shimogori, T; Kashiwagi, K; Igarashi, K; Shiokawa, K

1998-07-01

Xenopus early embryos contain relatively low levels of S-adenosyl-methionine decarboxylase (SAMDC) and its mRNA. When SAMDC mRNA was injected into Xenopus embryos, it was preserved until the blastula stage and induced a large increase in SAMDC activity. The SAMDC-overexpressed embryos developed normally until the blastula stage but at the early gastrula stage cells which received the mRNA, dissociated autonomously and stopped synthesizing protein. In a hypotonic medium, the dissociated cells, and hence whole embryos, autolyzed. However, in isotonic media dissociated cells did not autolyze, although they did not divide and their DNA and RNA synthesis activity was greatly inhibited. The effects of SAMDC overexpression were abolished by coinjection of ethylglyoxal-bis(guanylhydrazone) (EGBG), a specific inhibitor of SAMDC. In SAMDC-overexpressed embryos the level of putrescine decreased and that of spermidine increased, though to limited extents, resulting in a considerable decrease in the putrescine/spermidine ratio. However, direct injection of spermidine did not mimic the effect of SAMDC overexpression, and putrescine coinjected with SAMDC mRNA to maintain the normal putrescine/spermidine ratio did not rescue the embryos. Conversely, the level of S-adenosylmethionine (SAM) greatly decreased and coinjection of SAM, which restored the level of SAM, rescued the embryos. We concluded that in SAMDC-overexpressed embryos a SAM-deficient state was induced and this caused cell dissociation and inhibition of transition from the blastula to gastrula stage. We suggest that the SAM-deficient embryos obtained in the present study provide a unique system for studying the cellular control mechanism underlying the blastula-gastrula transition.

The effect of repeated light-dark shifts on uterine receptivity and early gestation in mice undergoing embryo transfer.

PubMed

Goldstein, Cathy A; O'Brien, Louise M; Bergin, Ingrid L; Saunders, Thomas L

2018-04-01

Female shift workers are at increased risk for negative reproductive outcomes, and animal evidence suggests that manipulation of the light-dark cycle is detrimental to early gestation in female mice. Specifically, failure of implantation may be responsible for these findings. The objective of this study was to better delineate which reproductive processes are vulnerable to detrimental effects of maternal circadian disturbance. We exposed mice undergoing embryo transfer to repetitive phase advances of the photoperiod. Embryos were derived from donor sperm and eggs from mice living in normal light-dark conditions to isolate the effects of photoperiod disruption on uterine receptivity and early gestation. Twenty-eight mice receiving embryo transfer underwent an experimental light-dark condition (advance of lights on and lights off by 6 hours every 4 days). Twenty-eight mice remained in a normal light-dark condition. Animals lived in their assigned light-dark condition beginning 2 weeks prior to embryo transfer and ending the day of uterine necropsy (post-coitus day 14.5). Wilcoxon-Mann-Whitney test demonstrated no significant differences between control and experimental light-dark conditions in pups (Z=0.10, p=.92), resorptions (Z=0.20, p=.84), or implantations (Z=-0.34, p=.73). Pup and placental weights were similar between groups. In this investigation, uterine receptivity and maintenance of early gestation were preserved despite recurrent phase advances in photoperiod. This finding, in the context of the current literature, suggests that the negative effects of circadian disruption are mediated by reproductive processes upstream of implantation.

Global regulation of mRNA translation and stability in the early Drosophila embryo by the Smaug RNA-binding protein

PubMed Central

2014-01-01

Background Smaug is an RNA-binding protein that induces the degradation and represses the translation of mRNAs in the early Drosophila embryo. Smaug has two identified direct target mRNAs that it differentially regulates: nanos and Hsp83. Smaug represses the translation of nanos mRNA but has only a modest effect on its stability, whereas it destabilizes Hsp83 mRNA but has no detectable effect on Hsp83 translation. Smaug is required to destabilize more than one thousand mRNAs in the early embryo, but whether these transcripts represent direct targets of Smaug is unclear and the extent of Smaug-mediated translational repression is unknown. Results To gain a panoramic view of Smaug function in the early embryo, we identified mRNAs that are bound to Smaug using RNA co-immunoprecipitation followed by hybridization to DNA microarrays. We also identified mRNAs that are translationally repressed by Smaug using polysome gradients and microarrays. Comparison of the bound mRNAs to those that are translationally repressed by Smaug and those that require Smaug for their degradation suggests that a large fraction of Smaug’s target mRNAs are both translationally repressed and degraded by Smaug. Smaug directly regulates components of the TRiC/CCT chaperonin, the proteasome regulatory particle and lipid droplets, as well as many metabolic enzymes, including several glycolytic enzymes. Conclusions Smaug plays a direct and global role in regulating the translation and stability of a large fraction of the mRNAs in the early Drosophila embryo, and has unanticipated functions in control of protein folding and degradation, lipid droplet function and metabolism. PMID:24393533

[Effect of human oviductal embryotrophic factors on gene expression of mouse preimplantation embryos].

PubMed

Yao, Yuan-Qing; Lee, Kai-Fai; Xu, Jia-Seng; Ho, Pak-Chung; Yeung, Shu-Biu

2007-09-01

To investigate the effect of embryotrophic factors (ETF) from human oviductal cells on gene expression of mouse early developmental embryos and discuss the role of fallopian tube in early development of embryos. ETF was isolated from conditioned medium of human oviductal cell line by sequential liquid chromatographic systems. Mouse embryos were treated by ETF in vitro. Using differential display RT-PCR, the gene expression of embryos treated by ETF was compared with embryos without ETF treatment. The differentially expressed genes were separated, re-amplified, cloned and sequenced. Gene expression profiles of embryos with ETF treatment was different from embryos without this treatment. Eight differentially expressed genes were cloned and sequenced. These genes functioned in RNA degradation, synthesis, splicing, protein trafficking, cellular differentiation and embryo development. Embryotrophic factors from human oviductal cells affect gene expression of early developmental embryos. The human oviductal cells play wide roles in early developmental stages of embryos.

Nucleolus Precursor Bodies and Ribosome Biogenesis in Early Mammalian Embryos: Old Theories and New Discoveries.

PubMed

Fulka, Helena; Aoki, Fugaku

2016-06-01

In mammals, mature oocytes and early preimplantation embryos contain transcriptionally inactive structures termed nucleolus precursor bodies instead of the typical fibrillo-granular nucleoli. These nuclear organelles are essential and strictly of maternal origin. If they are removed from oocytes, the resulting embryos are unable to replace them and consequently fail to develop. Historically, nucleolus precursor bodies have been perceived as a passive repository site of nucleolar proteins that are required for embryos to form fully functional nucleoli. Recent results, however, contradict this long-standing dogma and show that these organelles are dispensable for nucleologenesis and ribosome biogenesis. In this article, we discuss the possible roles of nucleolus precursor bodies and propose how they might be involved in embryogenesis. Furthermore, we argue that these organelles are essential only shortly after fertilization and suggest that they might actively participate in centromeric chromatin establishment. © 2016 by the Society for the Study of Reproduction, Inc.

Oxygenated drinking water enhances immune activity in broiler chicks and increases survivability against Salmonella Gallinarum in experimentally infected broiler chicks.

PubMed

Jung, Bock-Gie; Lee, Jin-A; Nam, Kyoung-Woo; Lee, Bong-Joo

2012-03-01

It has been suggested that drinking oxygenated water may improve oxygen availability, which may increase vitality and improving immune activity. The present study evaluated the immune enhancing effects of oxygenated drinking water in broiler chicks and demonstrated the protective efficacy of oxygenated drinking water against Salmonella Gallinarum in experimentally infected broiler chicks. Continuous drinking of oxygenated water markedly increased serum lysozyme activity, peripheral blood mononuclear cell proliferation and the CD4(+)/CD8(+) splenocyte ratio in broiler chicks. In the chicks experimentally infected with S. Gallinarum, oxygenated drinking water alleviated symptoms and increased survival. These findings suggest that oxygenated drinking water enhances immune activity in broiler chicks, and increases survivability against S. Gallinarum in experimentally infected broiler chicks.

Single cell transcriptome profiling of developing chick retinal cells.

PubMed

Laboissonniere, Lauren A; Martin, Gregory M; Goetz, Jillian J; Bi, Ran; Pope, Brock; Weinand, Kallie; Ellson, Laura; Fru, Diane; Lee, Miranda; Wester, Andrea K; Liu, Peng; Trimarchi, Jeffrey M

2017-08-15

The vertebrate retina is a specialized photosensitive tissue comprised of six neuronal and one glial cell types, each of which develops in prescribed proportions at overlapping timepoints from a common progenitor pool. While each of these cells has a specific function contributing to proper vision in the mature animal, their differential representation in the retina as well as the presence of distinctive cellular subtypes makes identifying the transcriptomic signatures that lead to each retinal cell's fate determination and development challenging. We have analyzed transcriptomes from individual cells isolated from the chick retina throughout retinogenesis. While we focused our efforts on the retinal ganglion cells, our transcriptomes of developing chick cells also contained representation from multiple retinal cell types, including photoreceptors and interneurons at different stages of development. Most interesting was the identification of transcriptomes from individual mixed lineage progenitor cells in the chick as these cells offer a window into the cell fate decision-making process. Taken together, these data sets will enable us to uncover the most critical genes acting in the steps of cell fate determination and early differentiation of various retinal cell types. © 2017 Wiley Periodicals, Inc.

Teratogenic efects of injected methylmercury on avian embryos

USGS Publications Warehouse

Heinz, Gary H.; Hoffman, David J.; Klimstra, Jon D.; Stebbins, Katherine R.; Kondrad, Shannon L.; Erwin, Carol A.

2011-01-01

Controlled laboratory studies with game farm mallards (Anas platyrhynchos) and chickens (Gallus gallus) have demonstrated that methylmercury can cause teratogenic effects in birds, but studies with wild species of birds are lacking. To address this need, doses of methylmercury chloride were injected into the eggs of 25 species of birds, and the dead embryos and hatched chicks were examined for external deformities. When data for controls were summed across all 25 species tested and across all types of deformities, 24 individuals out of a total of 1,533 (a rate of 1.57%) exhibited at least one deformity. In contrast, when data for all of the mercury treatments and all 25 species were summed, 188 deformed individuals out of a total of 2,292 (8.20%) were found. Some deformities, such as lordosis and scoliosis (twisting of the spine), misshapen heads, shortening or twisting of the neck, and deformities of the wings, were seldom observed in controls but occurred in much greater frequency in Hg-treated individuals. Only 0.59% of individual control dead embryos and hatchlings exhibited multiple deformities versus 3.18% for Hg-dosed dead embryos and hatchlings. Methylmercury seems to have a widespread teratogenic potential across many species of birds.

Blastomere biopsy influences epigenetic reprogramming during early embryo development, which impacts neural development and function in resulting mice.

PubMed

Wu, Yibo; Lv, Zhuo; Yang, Yang; Dong, Guoying; Yu, Yang; Cui, Yiqiang; Tong, Man; Wang, Liu; Zhou, Zuomin; Zhu, Hui; Zhou, Qi; Sha, Jiahao

2014-05-01

Blastomere biopsy is used in preimplantation genetic diagnosis; however, the long-term implications on the offspring are poorly characterized. We previously reported a high risk of memory defects in adult biopsied mice. Here, we assessed nervous function of aged biopsied mice and further investigated the mechanism of neural impairment after biopsy. We found that aged biopsied mice had poorer spatial learning ability, increased neuron degeneration, and altered expression of proteins involved in neural degeneration or dysfunction in the brain compared to aged control mice. Furthermore, the MeDIP assay indicated a genome-wide low methylation in the brains of adult biopsied mice when compared to the controls, and most of the genes containing differentially methylated loci in promoter regions were associated with neural disorders. When we further compared the genomic DNA methylation profiles of 7.5-days postconception (dpc) embryos between the biopsy and control group, we found the whole genome low methylation in the biopsied group, suggesting that blastomere biopsy was an obstacle to de novo methylation during early embryo development. Further analysis on mRNA profiles of 4.5-dpc embryos indicated that reduced expression of de novo methylation genes in biopsied embryos may impact de novo methylation. In conclusion, we demonstrate an abnormal neural development and function in mice generated after blastomere biopsy. The impaired epigenetic reprogramming during early embryo development may be the latent mechanism contributing to the impairment of the nervous system in the biopsied mice, which results in a hypomethylation status in their brains.

Early Embryo Development in Fucus distichus Is Auxin Sensitive1

PubMed Central

Basu, Swati; Sun, Haiguo; Brian, Leigh; Quatrano, Ralph L.; Muday, Gloria K.

2002-01-01

Auxin and polar auxin transport have been implicated in controlling embryo development in land plants. The goal of these studies was to determine if auxin and auxin transport are also important during the earliest stages of development in embryos of the brown alga Fucus distichus. Indole-3-acetic acid (IAA) was identified in F. distichus embryos and mature tissues by gas chromatography-mass spectroscopy. F. distichus embryos accumulate [3H]IAA and an inhibitor of IAA efflux, naphthylphthalamic acid (NPA), elevates IAA accumulation, suggesting the presence of an auxin efflux protein complex similar to that found in land plants. F. distichus embryos normally develop with a single unbranched rhizoid, but growth on IAA leads to formation of multiple rhizoids and growth on NPA leads to formation of embryos with branched rhizoids, at concentrations that are active in auxin accumulation assays. The effects of IAA and NPA are complete before 6 h after fertilization (AF), which is before rhizoid germination and cell division. The maximal effects of IAA and NPA are between 3.5 and 5 h AF and 4 and 5.5 h AF, respectively. Although, the location of the planes of cell division was significantly altered in NPA- and IAA-treated embryos, these abnormal divisions occurred after abnormal rhizoid initiation and branching was observed. The results of this study suggest that auxin acts in the formation of apical basal patterns in F. distichus embryo development. PMID:12226509

Utilization of ketone bodies by chick brain and spinal cord during embryonic and postnatal development.

PubMed

Linares, A; Caamaño, G J; Diaz, R; Gonzalez, F J; Garcia-Peregrin, E

1993-10-01

Lipid synthesis from acetoacetate and 3-hydroxybutyrate was studied in chick embryo from 15 to 21 days and in chick neonate from 1 to 21 days. Embryonic spinal cord showed higher ability than brain to incorporate acetoacetate into total lipids, although a sharp decrease was found at hatching. 3-Hydroxybutyrate incorporation into total lipids was also higher in spinal cord than in brain, especially during the embryonic period. Phospholipids were the main lipids formed in both tissues from both precursors. An appreciable percentage of radioactivity was also recovered as free cholesterol, especially during the embryonic phase. The developmental patterns of amino acid synthesis from acetoacetate and 3-hydroxybutyrate were similar in both tissues: a clear increase after hatching was followed by a decrease at day 4 of neonatal life. Acetoacetate was a better substrate for amino acid synthesis than 3-hydroxybutyrate during the embryonic development in both tissues. Oxidation of both precursors to CO2 strongly decreased between 15 and 21 days of embryonic development both in brain and spinal cord.

Characterizing early embryonic development of Brown Tsaiya Ducks (Anas platyrhynchos) in comparison with Taiwan Country Chicken (Gallus gallus domestics)

PubMed Central

Lumsangkul, Chompunut; Fan, Yang-Kwang; Chang, Shen-Chang; Ju, Jyh-Cherng

2018-01-01

Avian embryos are among the most convenient and the primary representatives for the study of classical embryology. It is well-known that the hatching time of duck embryos is approximately one week longer than that of chicken embryos. However, the key features associated with the slower embryonic development in ducks have not been adequately described. This study aimed to characterize the pattern and the speed of early embryogenesis in Brown Tsaiya Ducks (BTD) compared with those in Taiwan Country Chicken (TCC) by using growth parameters including embryonic crown-tail length (ECTL), primitive streak formation, somitogenesis, and other development-related parameters, during the first 72 h of incubation. Three hundred and sixty eggs from BTD and TCC, respectively, were incubated at 37.2°C, and were then dissected hourly to evaluate their developmental stages. We found that morphological changes of TCC embryos shared a major similarity with that of the Hamburger and Hamilton staging system during early chick embryogenesis. The initial primitive streak in TCC emerged between 6 and 7 h post-incubation, but its emergence was delayed until 10 to 13 h post-incubation in BTD. Similarly, the limb primordia (wing and limb buds) were observed at 51 h post-incubation in TCC embryos compared to 64 h post-incubation in BTD embryos. The allantois first appeared around 65 to 68 h in TCC embryos, but it was not observed in BTD embryos. At the 72 h post-incubation, 40 somites were clearly formed in TCC embryos while only 32 somites in BTD embryos. Overall, the BTD embryos developed approximately 16 h slower than the chicken embryo during the first 72 h of development. To our best knowledge, this is the first study to describe two distinct developmental time courses between TCC and BTD, which would facilitate future embryogenesis-related studies of the two important avian species in Taiwan. PMID:29742160

Analysis of NUAK1 and NUAK2 expression during early chick development reveals specific patterns in the developing head.

PubMed

Bekri, Abdelhamid; Billaud, Marc; Thélu, Jacques

2014-01-01

Several human diseases are associated with the NUAK1 and NUAK2 genes. These genes encode kinases, members of the AMPK-related kinases (ARK) gene family. Both NUAK1 and NUAK2 are known targets of the serine threonine kinase LKB1, a tumor suppressor involved in regulating cell polarity. While much is known about their functions in disease, their expression pattern in normal development has not been extensively studied. Here, we present the expression patterns for NUAK1 and NUAK2 in the chick during early-stage embryogenesis, until day 3 (Hamburger and Hamilton stage HH20). Several embryonic structures, in particular the nascent head, showed distinct expression levels. NUAK1 expression was first detected at stage HH6 in the rostral neural folds. It was then expressed (HH7-11) throughout the encephalalon, predominantly in the telencephalon and mesencephalon. NUAK1 expression was also detected in the splanchnic endoderm area at HH8-10, and in the vitellin vein derived from this area, but not in the heart. NUAK2 expression was first detected at stage HH6 in the neural folds. It was then found throughout the encephalon at stage HH20. Particular attention was paid in this study to the dorsal ectoderm at stages HH7 and HH8, where a local deficit or accumulation of NUAK2 mRNA were found to correlate with the direction of curvature of the neural plate. This is the first description of NUAK1 and NUAK2 expression patterns in the chick during early development; it reveals non-identical expression profiles for both genes in neural development.

Behavioural properties of chick somitic mesoderm and lateral plate when explanted in vitro.

PubMed

Bellairs, R; Sanders, E J; Portch, P A

1980-04-01

Tissue culture, time-lapse cinematographic and electron microscopic techniques have been used to study the properties of chick mesoderm at several stages of differentiation. Lateral plate, unsegmented mesoderm (segmental plate), and newly formed somites were dissected from stage-12 embryos, whilst dermo-myotomes and sclerotomes were dissected from stage-18 embryos. Each type of mesoderm was found to exhibit a characteristic pattern of behaviour. The explants from the unsegmented mesoderm from the newly formed somites and from the older embryos could be placed in a developmental sequence; with increasing differentiation they settled and spread on the substrate more readily, whether explanted as pieces of tissue or as individual cells, and it was concluded that this implied an increased adhesion to the substrate. Similarly, with increasing differentiation, the cells segmented at a faster rate. No significant differences could be discerned in the internal structure of the different types of cells, although differences in the general shape were apparent. The lateral plate mesoderm cells, which bear some resemblances to the unsegmented mesoderm cells in the embryo, also show some morphological resemblances to them in vitro. However, the lateral plate cells had a much greater success in attaching to glass or platic substrates. They were also found to have the highest speed of locomotion of all the tissues studied, whereas the unsegmented had the lowest. It is concluded therefore, that although cells may look similar to one another morphologically, their behaviour may differ greatly, probably because they are already partially determined.

Cytoskeletal changes in oocytes and early embryos during in vitro fertilization process in mice.

PubMed

Gumus, E; Bulut, H E; Kaloglu, C

2010-02-01

The cytoskeleton plays crucial roles in the development and fertilization of germ cells and in the early embryo development. The growth, maturation and fertilization of oocytes require an active movement and a correct localization of cellular organelles. This is performed by the re-organization of microtubules and actin filaments. Therefore, the aim of the present study was to determine the changes in cytoskeleton during in vitro fertilization process using appropriate immunofluorescence techniques. While the chromatin content was found to be scattered throughout the nucleus during the oocyte maturation period, it was seen only around nucleolus following the completion of the maturation. Microtubules, during oocyte maturation, were regularly distributed throughout the ooplasm which was then localized in the subcortical region of oocytes. Similarly microfilaments were scattered throughout the ooplasm during the oocyte maturation period whereas they were seen in the subcortical region around the polar body and above the meiotic spindle throughout the late developmental stages. In conclusion, those changes occurred in microtubules and microfilaments might be closely related to the re-organization of the genetic material during the oocyte maturation and early embryo development.

Embryonic Exposure to Valproic Acid Impairs Social Predispositions of Newly-Hatched Chicks.

PubMed

Sgadò, Paola; Rosa-Salva, Orsola; Versace, Elisabetta; Vallortigara, Giorgio

2018-04-12

Biological predispositions to attend to visual cues, such as those associated with face-like stimuli or with biological motion, guide social behavior from the first moments of life and have been documented in human neonates, infant monkeys and domestic chicks. Impairments of social predispositions have been recently reported in neonates at high familial risk of Autism Spectrum Disorder (ASD). Using embryonic exposure to valproic acid (VPA), an anticonvulsant associated to increased risk of developing ASD, we modeled ASD behavioral deficits in domestic chicks. We then assessed their spontaneous social predispositions by comparing approach responses to a stimulus containing a face configuration, a stuffed hen, vs. a scrambled version of it. We found that this social predisposition was abolished in VPA-treated chicks, whereas experience-dependent mechanisms associated with filial imprinting were not affected. Our results suggest a specific effect of VPA on the development of biologically-predisposed social orienting mechanisms, opening new perspectives to investigate the neurobiological mechanisms involved in early ASD symptoms.

Development of the embryonic heat shock response and the impact of repeated thermal stress in early stage lake whitefish (Coregonus clupeaformis) embryos.

PubMed

Whitehouse, Lindy M; McDougall, Chance S; Stefanovic, Daniel I; Boreham, Douglas R; Somers, Christopher M; Wilson, Joanna Y; Manzon, Richard G

2017-10-01

Lake whitefish (Coregonus clupeaformis) embryos were exposed to thermal stress (TS) at different developmental stages to determine when the heat shock response (HSR) can be initiated and if it is altered by exposure to repeated TS. First, embryos were subject to one of three different TS temperatures (6, 9, or 12°C above control) at 4 points in development (21, 38, 60 and 70 days post-fertilisation (dpf)) for 2h followed by a 2h recovery to understand the ontogeny of the HSR. A second experiment explored the effects of repeated TS on the HSR in embryos from 15 to 75 dpf. Embryos were subjected to one of two TS regimes; +6°C TS for 1h every 6 days or +9°C TS for 1h every 6 days. Following a 2h recovery, a subset of embryos was sampled. Our results show that embryos could initiate a HSR via upregulation of heat shock protein 70 (hsp70) mRNA at all developmental ages studied, but that this response varied with age and was only observed with a TS of +9 or +12°C. In comparison, when embryos received multiple TS treatments, hsp70 was not induced in response to the 1h TS and 2h recovery, and a downregulation was observed at 39 dpf. Downregulation of hsp47 and hsp90α mRNA was also observed in early age embryos. Collectively, these data suggest that embryos are capable of initiating a HSR at early age and throughout embryogenesis, but that repeated TS can alter the HSR, and may result in either reduced responsiveness or a downregulation of inducible hsps. Our findings warrant further investigation into both the short- and long-term effects of repeated TS on lake whitefish development. Copyright © 2017 Elsevier Ltd. All rights reserved.

Learning-related changes in Fos-like immunoreactivity in the chick forebrain after imprinting.

PubMed Central

McCabe, B J; Horn, G

1994-01-01

The intermediate and medial part of the hyperstriatum ventrale (IMHV) is a part of the chick forebrain that is critical for the learning process of imprinting and may be a site of information storage. Chicks were either trained on an imprinting stimulus or dark-reared. Trained chicks were classified as good or poor learners by their preference score (a measure of the strength of imprinting). A monoclonal antibody against the immediate early gene product Fos was applied to sections through IMHV and other forebrain regions. In the IMHV, significantly more immunopositive nuclei were counted in good learners than in poor learners or dark-reared chicks. There was a positive correlation between counts of labeled nuclei and preference score that was not attributable to sensory activity per se, locomotor activity during training, or a predisposition to learn well; rather, the results indicated that the change in Fos immunoreactivity in the IMHV was related to learning. In the hyperstriatum accessorium, significantly fewer immunopositive nuclei were counted in good learners than in poor learners or in dark-reared chicks. In the dorsolateral hippocampal region, more immunopositive nuclei were counted in trained than in dark-reared chicks. No significant effects of training were found in the anterior hyperstriatum ventrale, lobus parolfactorius, neostriatum, medial hippocampal region, or ventrolateral hippocampal region, but counts in this last region were positively correlated with training approach. The results for IMHV implicate Fos or Fos-related proteins in memory processes and pave the way for the identification of the cell types that show the learning-related increase in gene expression. Images PMID:7972076

Somatic mutations reveal asymmetric cellular dynamics in the early human embryo

DOE PAGES

Ju, Young Seok; Martincorena, Inigo; Gerstung, Moritz; ...

2017-03-22

Somatic cells acquire mutations throughout the course of an individual’s life. Mutations occurring early in embryogenesis are often present in a substantial proportion of, but not all, cells in postnatal humans and thus have particular characteristics and effects. Depending on their location in the genome and the proportion of cells they are present in, these mosaic mutations can cause a wide range of genetic disease syndromes and predispose carriers to cancer. They have a high chance of being transmitted to offspring as de novo germline mutations and, in principle, can provide insights into early human embryonic cell lineages and theirmore » contributions to adult tissues. Although it is known that gross chromosomal abnormalities are remarkably common in early human embryos, our understanding of early embryonic somatic mutations is very limited. Here we use whole-genome sequences of normal blood from 241 adults to identify 163 early embryonic mutations. We estimate that approximately three base substitution mutations occur per cell per cell-doubling event in early human embryogenesis and these are mainly attributable to two known mutational signatures. We used the mutations to reconstruct developmental lineages of adult cells and demonstrate that the two daughter cells of many early embryonic cell-doubling events contribute asymmetrically to adult blood at an approximately 2:1 ratio. As a result, this study therefore provides insights into the mutation rates, mutational processes and developmental outcomes of cell dynamics that operate during early human embryogenesis.« less

Somatic mutations reveal asymmetric cellular dynamics in the early human embryo

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

Ju, Young Seok; Martincorena, Inigo; Gerstung, Moritz

Somatic cells acquire mutations throughout the course of an individual’s life. Mutations occurring early in embryogenesis are often present in a substantial proportion of, but not all, cells in postnatal humans and thus have particular characteristics and effects. Depending on their location in the genome and the proportion of cells they are present in, these mosaic mutations can cause a wide range of genetic disease syndromes and predispose carriers to cancer. They have a high chance of being transmitted to offspring as de novo germline mutations and, in principle, can provide insights into early human embryonic cell lineages and theirmore » contributions to adult tissues. Although it is known that gross chromosomal abnormalities are remarkably common in early human embryos, our understanding of early embryonic somatic mutations is very limited. Here we use whole-genome sequences of normal blood from 241 adults to identify 163 early embryonic mutations. We estimate that approximately three base substitution mutations occur per cell per cell-doubling event in early human embryogenesis and these are mainly attributable to two known mutational signatures. We used the mutations to reconstruct developmental lineages of adult cells and demonstrate that the two daughter cells of many early embryonic cell-doubling events contribute asymmetrically to adult blood at an approximately 2:1 ratio. As a result, this study therefore provides insights into the mutation rates, mutational processes and developmental outcomes of cell dynamics that operate during early human embryogenesis.« less

Effects of age, vitamin D3, and fructooligosaccharides on bone growth and skeletal integrity of broiler chicks.

PubMed

Kim, W K; Bloomfield, S A; Ricke, S C

2011-11-01

A study was conducted to evaluate the effects of age, vitamin D(3), and fructooligosaccharides (FOS) on bone mineral density (BMD), bone mineral content (BMC), cortical thickness, cortical and trabecular area, and mechanical properties in broiler chicks using peripheral quantitative computed tomography and mechanical testing. A total of 54 male broiler chicks (1 d old) were placed in battery brooders and fed a corn-soybean starter diet for 7 d. After 7 d, the chicks were randomly assigned to pens of 3 birds each. Each treatment was replicated 3 times. There were 6 treatments: 1) early age control (control 1); 2) control 2; 3) 125 µg/kg of vitamin D(3); 4) 250 µg/kg of vitamin D(3); 5) 2% FOS); and 6) 4% FOS. The control 1 chicks were fed a control broiler diet and killed on d 14 to collect femurs for bone analyses. The remaining groups were killed on d 21. Femurs from 3-wk-old chicks showed greater midshaft cortical BMD, BMC, bone area, thickness, and marrow area than those from 2-wk-old chicks (P = 0.016, 0.0003, 0.0002, 0.01, and 0.0001, respectively). Total, cortical, and trabecular BMD of chick proximal femurs were not influenced by age. However, BMC and bone area were significantly affected by age. The femurs of 2-wk-old chicks exhibited significantly lower stiffness and ultimate load than those of 3-wk-old chicks (P = 0.0001), whereas ultimate stress and elastic modulus of the femurs of 2-wk-old chicks were significantly higher than that of femurs of 3-wk-old chicks (P = 0.0001). Chicks fed 250 µg/kg of vitamin D(3) exhibited significantly greater midshaft cortical BMC (P = 0.04), bone area (P = 0.04), and thickness (P = 0.03) than control 2, 2% FOS, or 4% FOS chicks. In summary, our study suggests that high levels of vitamin D(3) can increase bone growth and mineral deposition in broiler chicks. However, FOS did not have any beneficial effects on bone growth and skeletal integrity. Age is an important factor influencing skeletal integrity and mechanical

Arabidopsis mitochondrial protein slow embryo development1 is essential for embryo development

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

Ju, Yan; Liu, Chunying; Lu, Wenwen

The plant seeds formation are crucial parts in reproductive process in seed plants as well as food source for humans. Proper embryo development ensure viable seed formation. Here, we showed an Arabidopsis T-DNA insertion mutant slow embryo development1 (sed1) which exhibited retarded embryogenesis, led to aborted seeds. Embryo without SED1 developed slower compared to normal one and could be recognized at early globular stage by its white appearance. In later development stage, storage accumulated poorly with less protein and lipid body production. In vitro culture did not rescue albino embryo. SED1 encoded a protein targeted to mitochondria. Transmission electron microscopic analysismore » revealed that mitochondria developed abnormally, and more strikingly plastid failed to construct grana in time in sed1/sed1 embryo. These data indicated that SED1 is indispensable for embryogenesis in Arabidopsis, and the mitochondria may be involved in the regulation of many aspects of seed development. -- Highlights: •Arabidopsis SED1 is essential for embryo development. •The sed1 embryo accumulates less storage and has abnormal ultrastructure. •SED1 localizes to the mitochondrion.« less

[Is there either agenesis or regression of the Mullerian duct in female bird embryos under the influence of male hormone?].

PubMed

Lutz-Ostertag, Y; Lutz, H

1976-01-01

The natural occurence of "Free-Martinism" in Birds and the chorio-allantoïc grafting experiments of testis fragments on female chick host-embryos allow to the authors to define the manner provoking the entire or partial disappearance of the müllerian ducts and to state exactly if the phenomenon is a agenesis or a regression.

Interactive effects of temperature and hypoxia on heart rate and oxygen consumption of the 3-day old chicken embryo.

PubMed

Mortola, Jacopo P; Wills, Kathryn; Trippenbach, Teresa; Al Awam, Khalid

2010-03-01

In the chick embryo at day 3, gas exchange occurs by diffusion and oxygen consumption (V(O(2))) does not depend on the cardiovascular convection of O(2). Whether or not this is the case in hypoxia is not known and represents the aim of the study. The heart of chicken embryos at 72 h (stage HH18) was filmed through a window of the eggshell by a camera attached to a microscope. Stroke volume was estimated from the changes in heart silhouette between systole and diastole. V(O(2))was measured by a closed system methodology. In normoxia, a decrease in temperature (T) from 39 to 31 degrees C had parallel depressant effects on V(O(2))and HR. At 39 degrees C, a progressive decrease in O(2) lowered V(O(2)); HR was maintained until the O(2) threshold of approximately 15%. In severe hypoxia (4% O(2)) V(O(2))and HR were, respectively, approximately 12% and approximately 62% of normoxia. At 32 degrees C the hypoxic threshold for HR was significantly lower. During constant hypoxia (7% O(2)) V(O(2))did not respond to T, while the HR response was preserved. Stroke volume changed little with changes in T or O(2), except at 6 and 4% O(2), when it decreased by approximately 20 and 30%. In embryos growth-retarded because of incubation in chronic hypoxia, V(O(2))and HR responses to T and hypoxia were similar to those of normal embryos. We conclude that in the early embryo during hypoxia cardiovascular O(2) convection is not responsible for the drop in V(O(2)). The generalised hypometabolic response, in combination with the extremely small cardiac V(O(2)), probably explains the minor effects of hypoxia on cardiac activity. Copyright 2009 Elsevier Inc. All rights reserved.

Early feeding and early life housing conditions influence the response towards a noninfectious lung challenge in broilers.

PubMed

Simon, K; de Vries Reilingh, G; Bolhuis, J E; Kemp, B; Lammers, A

2015-09-01

Early life conditions such as feed and water availability immediately post hatch (PH) and housing conditions may influence immune development and therefore immune reactivity later in life. The current study addressed the consequences of a combination of these 2 early life conditions for immune reactivity, i.e., the specific antibody response towards a non-infectious lung challenge. Broiler chicks received feed and water either immediately p.h. or with a 72 h delay and were either reared in a floor or a cage system. At 4 weeks of age, chicks received either an intra-tracheally administered Escherichia coli lipopolysaccharide (LPS)/Human Serum Albumin (HUSA) challenge or a placebo, and antibody titers were measured up to day 14 after administration of the challenge. Chicks housed on the floor and which had a delayed access to feed p.h. showed the highest antibody titers against HuSA. These chicks also showed the strongest sickness response and poorest performance in response to the challenge, indicating that chicks with delayed access to feed might be more sensitive to an environment with higher antigenic pressure. In conclusion, results from the present study show that early life feeding strategy and housing conditions influence a chick's response to an immune challenge later in life. These 2 early life factors should therefore be taken into account when striving for a balance between disease resistance and performance in poultry. © 2015 Poultry Science Association Inc.

Radiation induced abnormalities in early in vitro mouse embryos

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

Kirkpatrick, J.F.

1973-08-01

Female mice were superovulated and mated, and the two-cell embryos were collected and cultured in vitro. The embryos were exposed to x-irradiation (0 to 491 rads) during the two-cell stage before the appearance of the next cleavage plate, placed in new unirradiated culture medium and observed during subsequent development. Morphological abnormalities, which occurred as a result of irradiation, included fragmentation, disintegration, granlation, incomplete cleavage, cleavage cessation, nuclear degeneration and pycnosis and cytoplasmic vacuolization. There was no damage to the zona pellucida. The types of abnormalities indicate an agreement with the results of previous in vivo studies. A distinct correlation existedmore » between morphological abnormalities and embryo death. The greatest number of abnormalities resulted within five hours following irradiation, but increased through 20 hours post-exposure. At doses above 300 rads, the magnitude of damage was greater in the in vitro embryos than that shown in previous in vivo studies. (auth)« less

Olfactory lateralization in the chick.

PubMed

Vallortigara, G; Andrew, R J

1994-04-01

Chicks using their right nostril (and so with direct olfactory input to the right hemisphere), and presented simultaneously with two objects identical in visual appearance with the rearing object, and differing only in odour, chose that which smelled like the rearing object. Chicks using the left nostril chose equally readily but at random. Earlier work, using similar tests, has shown special interest of the right hemisphere in change in visual properties of familiar stimuli, suggesting that analysis of a wide range of properties of a familiar stimulus may be an important function of the right hemisphere in the chick, with consequent detection of novelty.

Suramin inhibits bFGF-induced endothelial cell proliferation and angiogenesis in the chick chorioallantoic membrane.

PubMed Central

Danesi, R.; Del Bianchi, S.; Soldani, P.; Campagni, A.; La Rocca, R. V.; Myers, C. E.; Paparelli, A.; Del Tacca, M.

1993-01-01

The effects of suramin, an inhibitor of growth factor mitogenic activity, were evaluated on basic fibroblast growth factor (bFGF)-induced proliferation of bovine aortic endothelial cells and on angiogenesis in the chorioallantoic membrane (CAM) of chick embryos. The role of bFGF gene expression in endothelial cell growth was also investigated by using an antisense oligodeoxynucleotide to bFGF. The 4-fold increase in [3H]-thymidine uptake in endothelial cells in vitro upon stimulation with 10 ng ml-1 of bFGF was inhibited by suramin 300 micrograms ml-1. bFGF antisense oligomer (10 microM) reduced [3H]-thymidine incorporation in exponentially growing cells by 76%; this effect was reversed by bFGF 10 ng ml-1. In the CAM of chick embryos suramin 50 micrograms was a more potent inhibitor of angiogenesis than the combination of heparin 60 micrograms/hydrocortisone 50 micrograms; the mean value of the area with reduced vascularity was significantly larger in suramin-treated CAMs (2.4 cm2) than in heparin/hydrocortisone (0.6 cm2), while the reduction of vascular density was similar (- 35 and - 29% compared to controls, respectively), In conclusion, the effects of treatments with bFGF and bFGF antisense oligomer demonstrate that bFGF plays a relevant role in endothelial cell proliferation and may be the target of suramin since the drug is able to suppress basal and bFGF-induced endothelial cell growth; in addition to this, suramin is a more potent angiogenesis inhibitor in the CAM than the combination of heparin/hydrocortisone. Images Figure 1 Figure 4 PMID:7692920

In ovo trace element supplementation enhances expression of growth genes in embryo and immune genes in post-hatch broiler chickens.

PubMed

Goel, Akshat; Bhanja, Subrat K; Mehra, Manish; Mandal, Asitbaran; Pande, Veena

2016-06-01

Differential expression of growth- and immunity-related genes and post-hatch performances were evaluated in in ovo zinc (Zn), iodine (I) or selenium (Se) supplemented chicken embryos. There was about 9-18% reduction in hatchability of Zn, I or Se supplemented eggs. In ovo trace element supplementation did not improve post-hatch growth. Two-way analysis of data revealed significant effect (P > 0.01) of period, trace elements and their interactions. Expression of hepatic somatotropin, insulin-like growth factor-II and mucin gene was highest at 20(th) embryonic day but decreased during post-hatch periods. In ovo Zn or I supplemented embryos had higher expression of growth-related genes compared to the Se or un-injected control group. Expression of interleukin-6 was higher (P < 0.01) in in ovo I supplemented chicks (2.5-fold) but lower in the Zn and Se groups than in the un-injected control group. However, Zn and Se supplemented chicks had higher cellular immune gene expression. In vivo response to mitogen phytohaemaglutinin was also higher (P < 0.01) in Zn or Se supplemented chicks In ovo supplementation of Zn, I and Se did not improve the post-hatch growth, but increased growth-related gene expression. Iodine improved humoral immune gene expression whereas Zn and Se enhanced cell-mediated immune gene expression in broiler chickens. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Chicken interferome: avian interferon-stimulated genes identified by microarray and RNA-seq of primary chick embryo fibroblasts treated with a chicken type I interferon (IFN-α).

PubMed

Giotis, Efstathios S; Robey, Rebecca C; Skinner, Natalie G; Tomlinson, Christopher D; Goodbourn, Stephen; Skinner, Michael A

2016-08-05

Viruses that infect birds pose major threats-to the global supply of chicken, the major, universally-acceptable meat, and as zoonotic agents (e.g. avian influenza viruses H5N1 and H7N9). Controlling these viruses in birds as well as understanding their emergence into, and transmission amongst, humans will require considerable ingenuity and understanding of how different species defend themselves. The type I interferon-coordinated response constitutes the major antiviral innate defence. Although interferon was discovered in chicken cells, details of the response, particularly the identity of hundreds of stimulated genes, are far better described in mammals. Viruses induce interferon-stimulated genes but they also regulate the expression of many hundreds of cellular metabolic and structural genes to facilitate their replication. This study focusses on the potentially anti-viral genes by identifying those induced just by interferon in primary chick embryo fibroblasts. Three transcriptomic technologies were exploited: RNA-seq, a classical 3'-biased chicken microarray and a high density, "sense target", whole transcriptome chicken microarray, with each recognising 120-150 regulated genes (curated for duplication and incorrect assignment of some microarray probesets). Overall, the results are considered robust because 128 of the compiled, curated list of 193 regulated genes were detected by two, or more, of the technologies.

Physiological response of broiler embryos to different incubator temperature profiles and maternal flock age during incubation. 1. Embryonic metabolism and day-old chick quality.

PubMed

Hamidu, J A; Torres, C A; Johnson-Dahl, M L; Korver, D R

2018-05-18

Broiler strain, maternal age, and incubation temperature influence embryo metabolism. Hatching eggs were obtained from young (Y; 28 to 34 wk, $\\bar{\\rm x}$ = 31.2 wk), mid (M; 36 to 45 wk, $\\bar{\\rm x}$ = 40.5 wk) and old (O; 49 to 54 wk, $\\bar{\\rm x}$ = 51.4 wk) Ross 708 (n = 88; Experiment 1) and Ross 308 [(n = 45; Experiment 2: (Y; 25 to 34 wk, $\\bar{\\rm x}$ = 30.5 wk), (M; 35 to 44 wk, $\\bar{\\rm x}$ = 40.2 wk), and (O; 49 to 54 wk, $\\bar{\\rm x}$ = 51.6 wk)] breeders. Eggs were stored for 2 to 4 d (18°C, 73% RH), and incubated for 14 d at 37.5°C and 56% RH. At 15 d (E15), 8 fertile eggs per flock age were incubated in individual metabolic chambers at 36.0, 36.5, 37.0, or 37.5°C until E21.5. Each temperature was repeated one additional time. O2 consumption and CO2 production were used to calculate embryonic heat production (EHP). Embryo temperature was measured as eggshell temperature (EST). Initial egg weight was used as a covariate; significance was assessed at P < 0.05. In Ross 708, daily EHP tended to be higher in M and O than Y treatments at E16; EHP of M was higher than Y and O eggs at E18; M and O were higher than O eggs at E19. Incubation at 37.0°C resulted in the highest EHP from E15 to E21, except at E17. Embryos at 37.5°C had reduced EHP beyond E17. Daily EST from E15 to E21 was higher at 37.5 and 37.0°C than at 36.0 and 36.5°C. In Ross 308, daily EST was highest at 37.5°C except at E20. Incubation temperature and EST were highly correlated (R2 = 0.90 to 0.89; P < 0.001). Ross 708 chicks were longer and hatched earlier at 37.0°C than at 36.0 and 37.5°C. EST and EHP increased with incubation temperature in Ross 708. In Ross 308, maternal flock age and incubation temperature did not impact EHP. However, EST was highest at 37.5°C except at E20. Ross 708 was more sensitive to incubation temperature than Ross 308.

Shorter Exposures to Harder X-Rays Trigger Early Apoptotic Events in Xenopus laevis Embryos

PubMed Central

Dong, JiaJia; Mury, Sean P.; Drahos, Karen E.; Moscovitch, Marko

2010-01-01

Background A long-standing conventional view of radiation-induced apoptosis is that increased exposure results in augmented apoptosis in a biological system, with a threshold below which radiation doses do not cause any significant increase in cell death. The consequences of this belief impact the extent to which malignant diseases and non-malignant conditions are therapeutically treated and how radiation is used in combination with other therapies. Our research challenges the current dogma of dose-dependent induction of apoptosis and establishes a new parallel paradigm to the photoelectric effect in biological systems. Methodology/Principal Findings We explored how the energy of individual X-ray photons and exposure time, both factors that determine the total dose, influence the occurrence of cell death in early Xenopus embryo. Three different experimental scenarios were analyzed and morphological and biochemical hallmarks of apoptosis were evaluated. Initially, we examined cell death events in embryos exposed to increasing incident energies when the exposure time was preset. Then, we evaluated the embryo's response when the exposure time was augmented while the energy value remained constant. Lastly, we studied the incidence of apoptosis in embryos exposed to an equal total dose of radiation that resulted from increasing the incoming energy while lowering the exposure time. Conclusions/Significance Overall, our data establish that the energy of the incident photon is a major contributor to the outcome of the biological system. In particular, for embryos exposed under identical conditions and delivered the same absorbed dose of radiation, the response is significantly increased when shorter bursts of more energetic photons are used. These results suggest that biological organisms display properties similar to the photoelectric effect in physical systems and provide new insights into how radiation-mediated apoptosis should be understood and utilized for therapeutic

Role of nucleation-promoting factors in mouse early embryo development.

PubMed

Wang, Qiao-Chu; Liu, Jun; Wang, Fei; Duan, Xing; Dai, Xiao-Xin; Wang, Teng; Liu, Hong-Lin; Cui, Xiang-Shun; Sun, Shao-Chen; Kim, Nam-Hyung

2013-06-01

During mitosis nucleation-promoting factors (NPFs) bind to the Arp2/3 complex and activate actin assembly. JMY and WAVE2 are two critical members of the NPFs. Previous studies have demonstrated that NPFs promote multiple processes such as cell migration and cytokinesis. However, the role of NPFs in development of mammalian embryos is still unknown. Results of the present study show that the NPFs JMY and WAVE2 are critical for cytokinesis during development of mouse embryos. Both JMY and WAVE2 are expressed in mouse embryos. After injection of JMY or WAVE2 siRNA, all embryos failed to develop to the morula or blastocyst stages. Moreover, using fluorescence intensity analysis, we found that the expression of actin decreased, and multiple nuclei were observed within a single cell indicating that NPFs-induced actin reduction caused the failure of cell division. In addition, injection of JMY and WAVE2 siRNA also caused ARP2 degradation, indicating that involvement of NPFs in development of mouse embryos is mainly through regulation of ARP2/3-induced actin assembly. Taken together, these data suggested that WAVE2 and JMY are involved in development of mouse embryos, and their regulation may be through a NPFs-Arp2/3-actin pathway.

Right hemisphere advantage for social recognition in the chick.

PubMed

Vallortigara, G

1992-09-01

Recognition of familiar and unfamiliar conspecifics was studied in pair-reared chicks tested binocularly or with only one eye in use. Chicks were tested on day 3 in pairs composed of either cagemates or strangers. Social discrimination, as measured by the ratio "number of pecks at the strangers/total number of pecks" was impaired in right-eyed chicks with respect to left-eyed and binocular chicks. Male chicks showed higher levels of social pecking than females, and chicks that used both eyes showed higher pecking than monocular chicks. There were no significant differences in the total number of pecks (i.e. pecks at companions plus pecks at strangers) between right- and left-eyed chicks: the impairment in social discrimination of right-eyed chicks seemed to be due partly to a reduction in pecking at strangers and partly to an increase in pecking at companions. It is suggested that neural structures fed by the left eye (mainly located at the right hemisphere) are better at processing and/or storing of visual information which allows recognition of individual conspecifics. This may be part of a wider tendency to respond to small changes in any of a variety of intrinsic stimulus properties.

The role of Mixer in patterning the early Xenopus embryo.

PubMed

Kofron, Matt; Wylie, Chris; Heasman, Janet

2004-05-01

The transcription factor VegT, is required in early Xenopus embryos for the formation of both the mesoderm and endoderm germ layers. Inherited as a maternal mRNA localized only in vegetal cells, VegT activates the transcription of a large number of transcription factors, as well as signaling ligands that induce cells in the vegetal mass to form endoderm, and the marginal zone to form mesoderm. It is important now to understand the extent to which transcription factors downstream of VegT play individual, or overlapping, roles in the specification and patterning of the endoderm and mesoderm. In addition, it is important to understand the mechanism that specifies the boundary between endoderm and mesoderm. One of the downstream targets of VegT, the homeodomain protein Mixer, is expressed at high levels at the mesoderm/endoderm boundary at the late blastula stage. We therefore examined its functions by blocking its translation using morpholino oligos. In Mixer-depleted embryos, the expression of many signaling ligands and transcription factors was affected. In particular, we found that the expression of several genes, including several normally expressed in mesoderm, was upregulated. Functional assays of Mixer-depleted vegetal cells showed that they have increased mesoderm-inducing activity. This demonstrates that Mixer plays an essential role in controlling the amount of mesoderm induction by the vegetal cells.

Efficacy of using radio transmitters to monitor least tern chicks

USGS Publications Warehouse

Whittier, Joanna B.; Leslie, David M.

2005-01-01

Little is known about Least Tern (Sterna antillarum) chicks from the time they leave the nest until fledging because they are highly mobile and cryptically colored. We evaluated the efficacy of using radiotelemetry to monitor Interior Least Tern (S. a. athalassos) chicks at Salt Plains National Wildlife Refuge, Oklahoma. In 1999, we attached radio transmitters to 26 Least Tern chicks and tracked them for 2-17 days. No adults abandoned their chicks after transmitters were attached. Transmitters did not appear to alter growth rates of transmittered chicks (P = 0.36) or prevent feather growth, although dermal irritation was observed on one chick. However, without frequent reattachment, transmitters generally did not remain on chicks <1 week old for more than 2 days because of feather growth and transmitter removal, presumably by adult terns. Although the presence of transmitters did not adversely affect Least Tern chicks, future assessments should investigate nonintrusive methods to improve retention of transmitters on young chicks and reduce the number of times that chicks need to be handled.

Are Early Somatic Embryos of the Norway Spruce (Picea abies (L.) Karst.) Organised?

PubMed Central

Petrek, Jiri; Zitka, Ondrej; Adam, Vojtech; Bartusek, Karel; Anjum, Naser A.; Pereira, Eduarda; Havel, Ladislav; Kizek, Rene

2015-01-01

Background Somatic embryogenesis in conifer species has great potential for the forestry industry. Hence, a number of methods have been developed for their efficient and rapid propagation through somatic embryogenesis. Although information is available regarding the previous process-mediated generation of embryogenic cells to form somatic embryos, there is a dearth of information in the literature on the detailed structure of these clusters. Methodology/Principal Findings The main aim of this study was to provide a more detailed structure of the embryogenic tissue clusters obtained through the in vitro propagation of the Norway spruce (Picea abies (L.) Karst.). We primarily focused on the growth of early somatic embryos (ESEs). The data on ESE growth suggested that there may be clear distinctions between their inner and outer regions. Therefore, we selected ESEs collected on the 56th day after sub-cultivation to dissect the homogeneity of the ESE clusters. Two colourimetric assays (acetocarmine and fluorescein diacetate/propidium iodide staining) and one metabolic assay based on the use of 2,3,5-triphenyltetrazolium chloride uncovered large differences in the metabolic activity inside the cluster. Next, we performed nuclear magnetic resonance measurements. The ESE cluster seemed to be compactly aggregated during the first four weeks of cultivation; thereafter, the difference between the 1H nuclei concentration in the inner and outer clusters was more evident. There were clear differences in the visual appearance of embryos from the outer and inner regions. Finally, a cluster was divided into six parts (three each from the inner and the outer regions of the embryo) to determine their growth and viability. The innermost embryos (centripetally towards the cluster centre) could grow after sub-cultivation but exhibited the slowest rate and required the longest time to reach the common growth rate. To confirm our hypothesis on the organisation of the ESE cluster, we

Early Cambrian Pentamerous Cubozoan Embryos from South China

PubMed Central

Han, Jian; Kubota, Shin; Li, Guoxiang; Yao, Xiaoyong; Yang, Xiaoguang; Shu, Degan; Li, Yong; Kinoshita, Shunichi; Sasaki, Osamu; Komiya, Tsuyoshi; Yan, Gang

2013-01-01

Background Extant cubozoans are voracious predators characterized by their square shape, four evenly spaced outstretched tentacles and well-developed eyes. A few cubozoan fossils are known from the Middle Cambrian Marjum Formation of Utah and the well-known Carboniferous Mazon Creek Formation of Illinois. Undisputed cubozoan fossils were previously unknown from the early Cambrian; by that time probably all representatives of the living marine phyla, especially those of basal animals, should have evolved. Methods Microscopic fossils were recovered from a phosphatic limestone in the Lower Cambrian Kuanchuanpu Formation of South China using traditional acetic-acid maceration. Seven of the pre-hatched pentamerous cubozoan embryos, each of which bears five pairs of subumbrellar tentacle buds, were analyzed in detail through computed microtomography (Micro-CT) and scanning electron microscopy (SEM) without coating. Results The figured microscopic fossils are unequivocal pre-hatching embryos based on their spherical fertilization envelope and the enclosed soft-tissue that has preserved key anatomical features arranged in perfect pentaradial symmetry, allowing detailed comparison with modern cnidarians, especially medusozoans. A combination of features, such as the claustrum, gonad-lamella, suspensorium and velarium suspended by the frenula, occur exclusively in the gastrovascular system of extant cubozoans, indicating a cubozoan affinity for these fossils. Additionally, the interior anatomy of these embryonic cubozoan fossils unprecedentedly exhibits the development of many new septum-derived lamellae and well-partitioned gastric pockets unknown in living cubozoans, implying that ancestral cubozoans had already evolved highly specialized structures displaying unexpected complexity at the dawn of the Cambrian. The well-developed endodermic lamellae and gastric pockets developed in the late embryonic stages of these cubozoan fossils are comparable with extant pelagic

A technique for sexing fully developed embryos and early-instar larvae of the gypsy moth

Treesearch

Gilbert Levesque

1963-01-01

Because variation in sex ratio is an important factor in the population dynamics of the gypsy moth (Porthetria dispar), it is necessary to have some means of determining the ratio of males to females in a population at the beginning of the larval period as well as in the later stages. For determining the sex of fully developed embryos and early-...

Confocal imaging of whole vertebrate embryos reveals novel insights into molecular and cellular mechanisms of organ development

NASA Astrophysics Data System (ADS)

Hadel, Diana M.; Keller, Bradley B.; Sandell, Lisa L.

2014-03-01

Confocal microscopy has been an invaluable tool for studying cellular or sub-cellular biological processes. The study of vertebrate embryology is based largely on examination of whole embryos and organs. The application of confocal microscopy to immunostained whole mount embryos, combined with three dimensional (3D) image reconstruction technologies, opens new avenues for synthesizing molecular, cellular and anatomical analysis of vertebrate development. Optical cropping of the region of interest enables visualization of structures that are morphologically complex or obscured, and solid surface rendering of fluorescent signal facilitates understanding of 3D structures. We have applied these technologies to whole mount immunostained mouse embryos to visualize developmental morphogenesis of the mammalian inner ear and heart. Using molecular markers of neuron development and transgenic reporters of neural crest cell lineage we have examined development of inner ear neurons that originate from the otic vesicle, along with the supporting glial cells that derive from the neural crest. The image analysis reveals a previously unrecognized coordinated spatial organization between migratory neural crest cells and neurons of the cochleovestibular nerve. The images also enable visualization of early cochlear spiral nerve morphogenesis relative to the developing cochlea, demonstrating a heretofore unknown association of neural crest cells with extending peripheral neurite projections. We performed similar analysis of embryonic hearts in mouse and chick, documenting the distribution of adhesion molecules during septation of the outflow tract and remodeling of aortic arches. Surface rendering of lumen space defines the morphology in a manner similar to resin injection casting and micro-CT.

The adrenocortical response of tufted puffin chicks to nutritional deficits

USGS Publications Warehouse

Kitaysky, A.S.; Romano, Marc D.; Piatt, John F.; Wingfield, J.C.; Kikuchi, M.

2005-01-01

In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer their young from temporary food shortages, increased cort secretion could be detrimental to undernourished chicks. In a system where parents are insensitive to chick demands, low benefits and high costs of activation of the HPA-axis in hungry chicks should lead to a disassociation of the nutritional state of the young and the activity of its HPA-axis. We tested this novel hypothesis for the tufted puffin (Fratercula cirrhata), a seabird with intermittent provisioning of a nest-bound semi-precocial chick. We examined the HPA-axis activity of captive chicks exposed to the following: (1) a short-term (24 h) food deprivation; and (2) an array of prolonged (3 weeks) restrictions in feeding regimens. We found that in response to a short-term food deprivation chicks decreased baseline levels of cort and thyroid hormones. In response to prolonged restrictions, food-limited chicks exhibited signs of nutritional deficit: they had lower body mass, endogenous lipid reserves, and thyroid hormone titers compared to chicks fed ad libitum. However, baseline and maximum acute stress-induced levels of cort were also lower in food-restricted chicks compared to those of chicks fed ad libitum. These results support a major prediction of the study hypothesis that puffin chicks suppress HPA-axis activity in response to short- and long-term nutritional deficits. This physiological adaptation may allow a chick to extend its development in the nest, while eluding detrimental effects of chronic cort elevation. 

Essential Role of Chromatin Remodeling Protein Bptf in Early Mouse Embryos and Embryonic Stem Cells

PubMed Central

Landry, Joseph; Sharov, Alexei A.; Piao, Yulan; Sharova, Lioudmila V.; Xiao, Hua; Southon, Eileen; Matta, Jennifer; Tessarollo, Lino; Zhang, Ying E.; Ko, Minoru S. H.; Kuehn, Michael R.; Yamaguchi, Terry P.; Wu, Carl

2008-01-01

We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor), the largest subunit of NURF (Nucleosome Remodeling Factor) in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf−/− embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf−/− embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo. PMID:18974875

Fish embryos on land: terrestrial embryo deposition lowers oxygen uptake without altering growth or survival in the amphibious fish Kryptolebias marmoratus.

PubMed

Wells, Michael W; Turko, Andy J; Wright, Patricia A

2015-10-01

Few teleost fishes incubate embryos out of water, but the oxygen-rich terrestrial environment could provide advantages for early growth and development. We tested the hypothesis that embryonic oxygen uptake is limited in aquatic environments relative to air using the self-fertilizing amphibious mangrove rivulus, Kryptolebias marmoratus, which typically inhabits hypoxic, water-filled crab burrows. We found that adult mangrove rivulus released twice as many embryos in terrestrial versus aquatic environments and that air-reared embryos had accelerated developmental rates. Surprisingly, air-reared embryos consumed 44% less oxygen and possessed larger yolk reserves, but attained the same mass, length and chorion thickness. Water-reared embryos moved their opercula ∼2.5 more times per minute compared with air-reared embryos at 7 days post-release, which probably contributed to the higher rates of oxygen uptake and yolk utilization we observed. Genetically identical air- and water-reared embryos from the same parent were raised to maturity, but the embryonic environment did not affect growth, reproduction or emersion ability in adults. Therefore, although aspects of early development were plastic, these early differences were not sustained into adulthood. Kryptolebias marmoratus embryos hatched out of water when exposed to aerial hypoxia. We conclude that exposure to a terrestrial environment reduces the energetic costs of development partly by reducing the necessity of embryonic movements to dispel stagnant boundary layers. Terrestrial incubation of young would be especially beneficial to amphibious fishes that occupy aquatic habitats of poor water quality, assuming low terrestrial predation and desiccation risks. © 2015. Published by The Company of Biologists Ltd.

Mass stranding of wedge-tailed shearwater chicks in Hawaii

USGS Publications Warehouse

Work, Thierry M.; Rameyer, Robert

1999-01-01

Unusual numbers of wedge-tailed shearwater (Puffinus pacificus) chicks stranded on Oahu (Hawaii, USA) in 1994. Compared to healthy wedge-tailed shearwater (WTSW) chicks, stranded chicks were underweight, dehydrated, leukopenic, lymphopenic, eosinopenic, and heterophilic; some birds were toxemic and septic. Stranded chicks also were hypoglycemic and had elevated aspartate amino transferase levels. Most chicks apparently died from emaciation, dehydration, or bacteremia. Because many birds with bacteremia also had severe necrosis of the gastrointestinal (GI) mucosa associated with bacteria, we suspect the GI tract to be the source of disseminated bacterial infection. The identity of the bacteria was not confirmed. The daily number of chicks stranded was significantly related to average wind speeds, and the mortality coincided with the fledging period for WTSW. Strong southeasterly winds were a distinguishing meteorologic factor in 1994 and contributed to the distribution of stranded chicks on Oahu. More objective data on WTSW demographics would enhance future efforts to determine predisposing causes of WTSW wrecks and their effects on seabird colonies.

Endogenous Nod-Factor-Like Signal Molecules Promote Early Somatic Embryo Development in Norway Spruce1

PubMed Central

Dyachok, Julia V.; Wiweger, Malgorzata; Kenne, Lennart; von Arnold, Sara

2002-01-01

Embryogenic cultures of Norway spruce (Picea abies) are composed of pro-embryogenic masses (PEMs) and somatic embryos of various developmental stages. Auxin is important for PEM formation and proliferation. In this report we show that depletion of auxin blocks PEM development and causes large-scale cell death. Extracts of the media conditioned by embryogenic cultures stimulate development of PEM aggregates in auxin-deficient cultures. Partial characterization of the conditioning factor shows that it is a lipophilic, low-molecular-weight molecule, which is sensitive to chitinase and contains GlcNAc residues. On the basis of this information, we propose that the factor is a lipophilic chitin oligosaccharide (LCO). The amount of LCO correlates to the developmental stages of PEMs and embryos, with the highest level in the media conditioned by developmentally blocked cultures. LCO is not present in nonembryogenic cultures. Cell death, induced by withdrawal of auxin, is suppressed by extra supply of endogenous LCO or Nod factor from Rhizobium sp. NGR234. The effect can be mimicked by a chitotetraose or chitinase from Streptomyces griseus. Taken together, our data suggest that endogenous LCO acts as a signal molecule stimulating PEM and early embryo development in Norway spruce. PMID:11842156

Time-lapse culture with morphokinetic embryo selection improves pregnancy and live birth chances and reduces early pregnancy loss: a meta-analysis.

PubMed

Pribenszky, Csaba; Nilselid, Anna-Maria; Montag, Markus

2017-11-01

Embryo evaluation and selection is fundamental in clinical IVF. Time-lapse follow-up of embryo development comprises undisturbed culture and the application of the visual information to support embryo evaluation. A meta-analysis of randomized controlled trials was carried out to study whether time-lapse monitoring with the prospective use of a morphokinetic algorithm for selection of embryos improves overall clinical outcome (pregnancy, early pregnancy loss, stillbirth and live birth rate) compared with embryo selection based on single time-point morphology in IVF cycles. The meta-analysis of five randomized controlled trials (n = 1637) showed that the application of time-lapse monitoring was associated with a significantly higher ongoing clinical pregnancy rate (51.0% versus 39.9%), with a pooled odds ratio of 1.542 (P < 0.001), significantly lower early pregnancy loss (15.3% versus 21.3%; OR: 0.662; P = 0.019) and a significantly increased live birth rate (44.2% versus 31.3%; OR 1.668; P = 0.009). Difference in stillbirth was not significant between groups (4.7% versus 2.4%). Quality of the evidence was moderate to low owing to inconsistencies across the studies. Selective application and variability were also limitations. Although time-lapse is shown to significantly improve overall clinical outcome, further high-quality evidence is needed before universal conclusions can be drawn. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Transcriptome Analysis of Honeybee (Apis Mellifera) Haploid and Diploid Embryos Reveals Early Zygotic Transcription during Cleavage

PubMed Central

Pires, Camilla Valente; Freitas, Flávia Cristina de Paula; Cristino, Alexandre S.; Dearden, Peter K.; Simões, Zilá Luz Paulino

2016-01-01

In honeybees, the haplodiploid sex determination system promotes a unique embryogenesis process wherein females develop from fertilized eggs and males develop from unfertilized eggs. However, the developmental strategies of honeybees during early embryogenesis are virtually unknown. Similar to most animals, the honeybee oocytes are supplied with proteins and regulatory elements that support early embryogenesis. As the embryo develops, the zygotic genome is activated and zygotic products gradually replace the preloaded maternal material. The analysis of small RNA and mRNA libraries of mature oocytes and embryos originated from fertilized and unfertilized eggs has allowed us to explore the gene expression dynamics in the first steps of development and during the maternal-to-zygotic transition (MZT). We localized a short sequence motif identified as TAGteam motif and hypothesized to play a similar role in honeybees as in fruit flies, which includes the timing of early zygotic expression (MZT), a function sustained by the presence of the zelda ortholog, which is the main regulator of genome activation. Predicted microRNA (miRNA)-target interactions indicated that there were specific regulators of haploid and diploid embryonic development and an overlap of maternal and zygotic gene expression during the early steps of embryogenesis. Although a number of functions are highly conserved during the early steps of honeybee embryogenesis, the results showed that zygotic genome activation occurs earlier in honeybees than in Drosophila based on the presence of three primary miRNAs (pri-miRNAs) (ame-mir-375, ame-mir-34 and ame-mir-263b) during the cleavage stage in haploid and diploid embryonic development. PMID:26751956

West nile virus in American white pelican chicks: transmission, immunity, and survival

USGS Publications Warehouse

Sovada, Marsha A.; Pietz, Pamela J.; Hofmeister, Erik K.; Bartos, Alisa J.

2013-01-01

West Nile virus (WNV) causes significant mortality of American White Pelican chicks at northern plains colonies. We tested oropharyngeal/cloacal swabs from moribund chicks for shed WNV. Such shedding could enable chick-to-chick transmission and help explain why WNV spreads rapidly in colonies. WNV was detected on swabs from 11% of chicks in 2006 and 52% of chicks in 2007; however, viral titers were low. Before onset of WNV mortality, we tested blood from < 3-week-old chicks for antibodies to WNV; 5% of chicks were seropositive, suggesting passive transfer of maternal antibodies. Among near-fledged chicks, 41% tested positive for anti-WNV antibodies, indicating that they survived infection. Among years and colonies, cumulative incidence of WNV in chicks varied from 28% to 81%, whereas the proportion of chicks surviving WNV (i.e., seropositive) was 64–75%. Our data revealed that WNV kills chicks that likely would fledge in the absence of WNV, that infection of chicks is pervasive, and that significant numbers of chicks survive infection.

Avian maternal response to chick distress

PubMed Central

Edgar, J. L.; Lowe, J. C.; Paul, E. S.; Nicol, C. J.

2011-01-01

The extent to which an animal is affected by the pain or distress of a conspecific will depend on its capacity for empathy. Empathy most probably evolved to facilitate parental care, so the current study assessed whether birds responded to an aversive stimulus directed at their chicks. Domestic hens were exposed to two replicates of the following conditions in a counterbalanced order: control (C; hen and chicks undisturbed), air puff to chicks (APC; air puff directed at chicks at 30 s intervals), air puff to hen (APH; air puff directed at hen at 30 s intervals) and control with noise (CN; noise of air puff at 30 s intervals). During each test, the hens' behaviour and physiology were measured throughout a 10 min pre-treatment and a 10 min treatment period. Hens responded to APH and APC treatments with increased alertness, decreased preening behaviour and a reduction in eye temperature. No such changes occurred during any control period. Increased heart rate and maternal vocalization occurred exclusively during the APC treatment, even though chicks produced few distress vocalizations. The pronounced and specific reaction observed indicates that adult female birds possess at least one of the essential underpinning attributes of empathy. PMID:21389025

Spread of hatch and delayed feed access affect post hatch performance of female broiler chicks up to day 5.

PubMed

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

2014-04-01

It is not rare that newly hatched chicks remain without feed for about 24 to 48 h before they are placed on farms due to a series of logistic operations. Furthermore, the spread in hatching time can also mount up to 30 to 48 h for late v. early hatchers. In other words, the practice is a complex combination of spread of hatch and delayed feed access. The present study was aimed to investigate the combined effects of hatching time with a delay in feed access of 48 h, starting from their hatch-time (biological age). When chicks had access to feed immediately after hatch, late hatchers had a higher feed intake and relative growth rate up to day 5 compared with their early hatched counterparts. Feed deprivation during the first 48 h resulted in retarded early growth rate, which was further aggravated by an impaired feed intake after refeeding. In addition, the differential effects of hatching time on relative growth rate and feed intake observed in immediately fed chicks were eliminated by the 48 h feed delay. The yolk utilization after hatch was faster for the late hatchers up to biological day 2 regardless of the feeding treatments. Hatching muscle glycogen content was higher in the late hatchers compared with that of their early counterparts at hatch and at biological day 2 independent of feeding treatment. Moreover, the liver glycogen content of the late hatchers was also higher at hatch. For the immediately fed chicks, the proportional breast muscle weight of the late hatchers was higher at biological day 2 and 5. For the starved chicks, on the other hand, this effect was only observed after they had access to feed (biological day 5). The different plasma T3 levels at hatch may have contributed to the different post hatch performance. It is concluded that the spread of hatch influenced post hatch performance, especially appetite and growth at least until day 5. Moreover, the delay in feed access interacted with the hatching time and caused adverse effects on the

Selection and dynamics of embryonic stem cell integration into early mouse embryos

PubMed Central

Alexandrova, Stoyana; Kalkan, Tuzer; Humphreys, Peter; Riddell, Andrew; Scognamiglio, Roberta; Trumpp, Andreas; Nichols, Jennifer

2016-01-01

The process by which pluripotent cells incorporate into host embryos is of interest to investigate cell potency and cell fate decisions. Previous studies suggest that only a minority of the embryonic stem cell (ESC) inoculum contributes to the adult chimaera. How incoming cells are chosen for integration or elimination remains unclear. By comparing a heterogeneous mix of undifferentiated and differentiating ESCs (serum/LIF) with more homogeneous undifferentiated culture (2i/LIF), we examine the role of cellular heterogeneity in this process. Time-lapse ex vivo imaging revealed a drastic elimination of serum/LIF ESCs during early development in comparison with 2i/LIF ESCs. Using a fluorescent reporter for naive pluripotency (Rex1-GFP), we established that the acutely eliminated serum/LIF ESCs had started to differentiate. The rejected cells were apparently killed by apoptosis. We conclude that a selection process exists by which unwanted differentiating cells are eliminated from the embryo. However, occasional Rex1− cells were able to integrate. Upregulation of Rex1 occurred in a proportion of these cells, reflecting the potential of the embryonic environment to expedite diversion from differentiation priming to enhance the developing embryonic epiblast. PMID:26586221

Mortality, size of the gonads, and ultrastructure of primordial germ cell in chick embryos treated with gamma-irradiation or injected with donor cells.

PubMed

Maeda, T; Clark, M E; Etches, R J

1998-06-01

The effects of injection and/or gamma-irradiation prior to injection on mortality, size of the gonads, and ultrastructure of primordial germ cell (PGC) were examined after 5 d of incubation. The mortality of embryos injected with donor cells was significantly higher than that of control and irradiated embryos. All irradiated embryos were alive, although their development was delayed compared to those not exposed to irradiation. The size of the gonads of embryos injected with donor cells were similar to those of control embryos, however, the size of the gonads in irradiated embryos was significantly smaller than those of control embryos. The number of PGC in the gonads was significantly decreased by irradiation. There was no notable effect of irradiation or injection on the nuclei and cytoplasmic organelles in PGC.

Ontogeny of thermoregulation and energy metabolism in pygoscelid penguin chicks.

PubMed

Taylor, J R

1985-01-01

The ontogeny of thermoregulation and energy metabolism of chinstrap (Pygoscelis antarctica) and gentoo (P. papua) penguins was studied on King George Island, South Shetland Island, Antarctica. The major findings of this study are: Chinstrap and gentoo penguin chicks hatched completely poikilothermic, due to their poor heat-production ability at low ambient temperatures. They were able to maintain high body temperatures and metabolic rates only by being brooded by adults. Newly hatched chinstrap penguin chicks had, at a specified ambient temperature, significantly higher metabolic rates than newly hatched gentoos. Moreover, chinstrap chicks maintained a significantly higher body temperature. It is suggested that this is a non-acclimatory metabolic adaptation of chinstrap penguin chicks to the lower mean temperatures of their breeding areas. On the 15th day after hatching, chinstrap chicks were completely, and gentoo chicks almost completely, homeothermic. In spite of their high thermogenic capacity from about day 10, chicks were not at that time capable of controlling heat dissipation, and were still dependent on their parents. In older downy chicks and fledglings, heat loss at low temperatures, expressed as heat conductance (CA), was similar to that found for the adults of other penguin species. Just before moulting the CA of chicks was lower than after moulting. Moulting alone did not cause a clear increase in CA. Towards the end of their stay on land the CA of pre-fledged gentoos decreased by 31%. This decrease was not connected with the development of feathers or growth in the chicks' weight. The combination of the low CA and high SMR of chicks gave very low lower critical temperatures, near -15 degrees C. The wide thermoneutral zones of the chicks covered the whole range of air temperature variations in the breeding colonies of both species studied on King George Island. The CA values of homeothermic chinstrap chicks were not lower than those of gentoos

Microspore embryogenesis in wheat: new marker genes for early, middle and late stages of embryo development.

PubMed

Sánchez-Díaz, Rosa Angélica; Castillo, Ana María; Vallés, María Pilar

2013-09-01

Microspore embryogenesis involves reprogramming of the pollen immature cell towards embryogenesis. We have identified and characterized a collection of 14 genes induced along different morphological phases of microspore-derived embryo development in wheat (Triticum aestivum L.) anther culture. SERKs and FLAs genes previously associated with somatic embryogenesis and reproductive tissues, respectively, were also included in this analysis. Genes involved in signalling mechanisms such as TaTPD1-like and TAA1b, and two glutathione S-transferase (GSTF2 and GSTA2) were induced when microspores had acquired a 'star-like' morphology or had undergone the first divisions. Genes associated with control of plant development and stress response (TaNF-YA, TaAGL14, TaFLA26, CHI3, XIP-R; Tad1 and WALI6) were activated before exine rupture. When the multicellular structures have been released from the exine, TaEXPB4, TaAGP31-like and an unknown embryo-specific gene TaME1 were induced. Comparison of gene expression, between two wheat cultivars with different response to anther culture, showed that the profile of genes activated before exine rupture was shifted to earlier stages in the low responding cultivar. This collection of genes constitutes a value resource for study mechanism of intra-embryo communication, early pattern formation, cell wall modification and embryo differentiation.

Endometrium as an early sensor of in vitro embryo manipulation technologies

PubMed Central

Mansouri-Attia, Nadéra; Sandra, Olivier; Aubert, Julie; Degrelle, Séverine; Everts, Robin E.; Giraud-Delville, Corinne; Heyman, Yvan; Galio, Laurent; Hue, Isabelle; Yang, Xiangzhong; Tian, X. Cindy; Lewin, Harris A.; Renard, Jean-Paul

2009-01-01

Implantation is crucial for placental development that will subsequently impact fetal growth and pregnancy success with consequences on postnatal health. We postulated that the pattern of genes expressed by the endometrium when the embryo becomes attached to the mother uterus could account for the final outcome of a pregnancy. As a model, we used the bovine species where the embryo becomes progressively and permanently attached to the endometrium from day 20 of gestation onwards. At that stage, we compared the endometrial genes profiles in the presence of an in vivo fertilized embryo (AI) with the endometrial patterns obtained in the presence of nuclear transfer (SCNT) or in vitro fertilized embryos (IVF), both displaying lower and different potentials for term development. Our data provide evidence that the endometrium can be considered as a biological sensor able to fine-tune its physiology in response to the presence of embryos whose development will become altered much later after the implantation process. Compared with AI, numerous biological functions and several canonical pathways with a major impact on metabolism and immune function were found to be significantly altered in the endometrium of SCNT pregnancies at implantation, whereas the differences were less pronounced with IVF embryos. Determining the limits of the endometrial plasticity at the onset of implantation should bring new insights on the contribution of the maternal environment to the development of an embryo and the success of pregnancy. PMID:19297625

Identification and functional analysis of long non-coding RNAs in human and mouse early embryos based on single-cell transcriptome data

PubMed Central

Qiu, Jia-jun; Ren, Zhao-rui; Yan, Jing-bin

2016-01-01

Epigenetics regulations have an important role in fertilization and proper embryonic development, and several human diseases are associated with epigenetic modification disorders, such as Rett syndrome, Beckwith-Wiedemann syndrome and Angelman syndrome. However, the dynamics and functions of long non-coding RNAs (lncRNAs), one type of epigenetic regulators, in human pre-implantation development have not yet been demonstrated. In this study, a comprehensive analysis of human and mouse early-stage embryonic lncRNAs was performed based on public single-cell RNA sequencing data. Expression profile analysis revealed that lncRNAs are expressed in a developmental stage–specific manner during human early-stage embryonic development, whereas a more temporal-specific expression pattern was identified in mouse embryos. Weighted gene co-expression network analysis suggested that lncRNAs involved in human early-stage embryonic development are associated with several important functions and processes, such as oocyte maturation, zygotic genome activation and mitochondrial functions. We also found that the network of lncRNAs involved in zygotic genome activation was highly preservative between human and mouse embryos, whereas in other stages no strong correlation between human and mouse embryo was observed. This study provides insight into the molecular mechanism underlying lncRNA involvement in human pre-implantation embryonic development. PMID:27542205

Single-cell transcriptome of early embryos and cultured embryonic stem cells of cynomolgus monkeys

PubMed Central

Nakamura, Tomonori; Yabuta, Yukihiro; Okamoto, Ikuhiro; Sasaki, Kotaro; Iwatani, Chizuru; Tsuchiya, Hideaki; Saitou, Mitinori

2017-01-01

In mammals, the development of pluripotency and specification of primordial germ cells (PGCs) have been studied predominantly using mice as a model organism. However, divergences among mammalian species for such processes have begun to be recognized. Between humans and mice, pre-implantation development appears relatively similar, but the manner and morphology of post-implantation development are significantly different. Nevertheless, the embryogenesis just after implantation in primates, including the specification of PGCs, has been unexplored due to the difficulties in analyzing the embryos at relevant developmental stages. Here, we present a comprehensive single-cell transcriptome dataset of pre- and early post-implantation embryo cells, PGCs and embryonic stem cells (ESCs) of cynomolgus monkeys as a model of higher primates. The identities of each transcriptome were also validated rigorously by other way such as immunofluorescent analysis. The information reported here will serve as a foundation for our understanding of a wide range of processes in the developmental biology of primates, including humans. PMID:28649393

Making lineage decisions with biological noise: Lessons from the early mouse embryo.

PubMed

Simon, Claire S; Hadjantonakis, Anna-Katerina; Schröter, Christian

2018-04-30

Understanding how individual cells make fate decisions that lead to the faithful formation and homeostatic maintenance of tissues is a fundamental goal of contemporary developmental and stem cell biology. Seemingly uniform populations of stem cells and multipotent progenitors display a surprising degree of heterogeneity, primarily originating from the inherent stochastic nature of molecular processes underlying gene expression. Despite this heterogeneity, lineage decisions result in tissues of a defined size and with consistent proportions of differentiated cell types. Using the early mouse embryo as a model we review recent developments that have allowed the quantification of molecular intercellular heterogeneity during cell differentiation. We first discuss the relationship between these heterogeneities and developmental cellular potential. We then review recent theoretical approaches that formalize the mechanisms underlying fate decisions in the inner cell mass of the blastocyst stage embryo. These models build on our extensive knowledge of the genetic control of fate decisions in this system and will become essential tools for a rigorous understanding of the connection between noisy molecular processes and reproducible outcomes at the multicellular level. We conclude by suggesting that cell-to-cell communication provides a mechanism to exploit and buffer intercellular variability in a self-organized process that culminates in the reproducible formation of the mature mammalian blastocyst stage embryo that is ready for implantation into the maternal uterus. This article is categorized under: Gene Expression and Transcriptional Hierarchies > Cellular Differentiation Establishment of Spatial and Temporal Patterns > Regulation of Size, Proportion, and Timing Gene Expression and Transcriptional Hierarchies > Gene Networks and Genomics Gene Expression and Transcriptional Hierarchies > Quantitative Methods and Models. © 2018 Wiley Periodicals, Inc.

IN VITRO CULTURE OF POSTIMPLANTATION HAMSTER EMBRYOS

EPA Science Inventory

In vitro culture of intact rat and mouse embryos has been described extensively, but information on the culture of other species is sparse. The present study examined some culture requirements of early somite stage hamster embryos and assessed the embryotoxic effects of sodium sa...

Patterns of protein synthesis in oocytes and early embryos of Rana esculenta complex.

PubMed

Chen, P S; Stumm-Zollinger, E

1986-01-01

We have used isotopic labelling and both one-and two-dimensional electrophoretic procedures to analyse the protien synthesis patterns in oocytes and early embryos of three phenotypes of the European green frogs. The results demonstrated that protein patterns of Rana ridibunda and R. esculenta are identical, but that they differ from those of R. lessonae. Progeny of the lethal cross R. esculenta × R. esculenta showed a distinct delay in the appearance of stage-specific proteins during early embryogenesis. The heat-shock response of R. ridibunda and R. esculenta oocytes was found to be identical, but different from that of Xenopus laevis. The implications of these findings, with respect to hybridogenesis in R. esculenta complex and variations in the regulations of heat shock genes in different amphibian species, are discussed.

Reduced O2 concentration during CAM development--its effect on angiogenesis and gene expression in the broiler embryo CAM.

PubMed

Druyan, S; Levi, E

2012-01-01

Hypoxia during embryogenesis may induce changes in the development of some physiological regulatory systems, thereby causing permanent phenotypic changes in the embryo. Various levels of hypoxia at different time points during embryogenesis were found to affect both anatomical and physiological morphogenesis. These changes and adaptations depended on the timing, intensity, and duration of the hypoxic exposure and, moreover, were regulated by differential expression of developmentally important genes, mostly expressed in a stage- and time-dependent manner. Eggs incubated in a 17%-oxygen atmosphere for 12 h/d from E5 through E12 exhibited a clear and significant increase in the vascular area of the chorioallantoic membrane (CAM); an increase that was already significant within 12 h after the end of the 1st hypoxic exposures (E6). We used the combination of the genes, β-actin, RPLP0 and HPRT as a reference for gene expression profiling, in studying the expression levels of hypoxia-inducible factor 1-alpha (HIF1α), vascular endothelial growth factor alpha-2 (VEGF α 2), vascular endothelial growth factor receptor 2 (KDR), matrix metalloproteinase-2 (MMP2), and fibroblast growth factor 2 (FGF2), under normal and hypoxic conditions. In general, expression of all five investigated genes throughout the embryonic day of development had similar patterns of hypoxia-induced alterations. In E5.5 embryos, expression of HIF1α, MMP2, VEGFα2, and KDR was significantly higher in hypoxic embryos than in controls. In E6 embryos expression of HIF1α, VEGFα2, and FGF2 was significantly higher in hypoxic embryos than in controls. From E6.5 onward expression levels of the examined genes did not show any differences between hypoxic and control embryos. It can be concluded that in this experimental model, exposing broiler embryos to 17% O(2) from E5 to E7 induced significant angiogenesis, as expressed by the above genes. Further studies to examine whether this early exposure to hypoxic

l-Leucine acts as a potential agent in reducing body temperature at hatching and affords thermotolerance in broiler chicks.

PubMed

Han, Guofeng; Yang, Hui; Bahry, Mohammad A; Tran, Phuong V; Do, Phong H; Ikeda, Hiromi; Furuse, Mitsuhiro; Chowdhury, Vishwajit S

2017-02-01

Thermal manipulation (TM) of incubation temperature causes metabolic alterations and contributes to improving thermotolerance in chicks post hatching. However, there has been no report on amino acid metabolism during TM and the part it plays in thermotolerance. In this study, we therefore first analyzed free amino acid concentrations in the embryonic brain and liver during TM (38.6°C, 6h/d during embryonic day (ED) 10 to ED 18). It was found that leucine (Leu), phenylalanine and lysine were significantly decreased in the embryonic brain and liver. We then chose l-Leu and other branched-chain amino acids (l-isoleucine (L-Ile) and l-valine (l-Val)) for in ovo injection on ED 7 to reveal their roles in thermoregulation, growth, food intake and thermotolerance in chicks. It was found that in ovo injection of l-Leu, but not of l-Ileu or l-Val, caused a significant decline in body temperature at hatching and increased food intake and body weight gain in broiler chicks. Interestingly, in ovo injection of l-Leu resulted in the acquisition of thermotolerance under high ambient temperature (35±1°C for 180min) in comparison with the control thermoneutral temperature (28±1°C for 180min). These results indicate that the free amino acid concentrations during embryogenesis were altered by TM. l-Leu administration in eggs caused a reduction in body temperature at hatching, and afforded thermotolerance in heat-exposed young chicks, further suggesting that l-Leu may be one of the key metabolic factors involved in controlling body temperature in embryos, as well as in producing thermotolerance after hatching. Copyright © 2016 Elsevier Inc. All rights reserved.

Egg-in-Cube: Design and Fabrication of a Novel Artificial Eggshell with Functionalized Surface

PubMed Central

Huang, Wenjing; Arai, Fumihito; Kawahara, Tomohiro

2015-01-01

An eggshell is a porous microstructure that regulates the passage of gases to allow respiration. The chick embryo and its circulatory system enclosed by the eggshell has become an important model for biomedical research such as the control of angiogenesis, cancer therapy, and drug delivery test, because the use of embryo is ethically acceptable and it is inexpensive and small. However, chick embryo and extra-embryonic blood vessels cannot be accessed freely and has poor observability because the eggshell is tough and cannot be seen through, which limits its application. In this study, a novel artificial eggshell with functionalized surface is proposed, which allows the total amount of oxygen to pass into the egg for the chick embryo culturing and has high observability and accessibility for embryo manipulation. First, a 40-mm enclosed cubic-shaped eggshell consisting of a membrane structure and a rigid frame structure is designed, and then the threshold of the membrane thickness suitable for the embryo survival is figured out according to the oxygen-permeability of the membrane structure. The designed artificial eggshell was actually fabricated by using polydimethylsiloxane (PDMS) and polycarbonate (PC) in the current study. Using the fabricated eggshell, chick embryo and extra-embryonic blood vessels can be observed from multiple directions. To test the effectiveness of the design, the cubic eggshells were used to culture chick embryos and survivability was confirmed when PDMS membranes with adequate oxygen permeability were used. Since the surface of the eggshell is transparent, chick embryo tissue development could be observed during the culture period. Additionally, the chick embryo tissues could be accessed and manipulated from outside the cubic eggshell, by using mechanical tools without breakage of the eggshell. The proposed “Egg-in-Cube” with functionalized surface has great potential to serve as a promising platform for biomedical research. PMID

Characterisation of the dynamic behaviour of lipid droplets in the early mouse embryo using adaptive harmonic generation microscopy.

PubMed

Watanabe, Tomoko; Thayil, Anisha; Jesacher, Alexander; Grieve, Kate; Debarre, Delphine; Wilson, Tony; Booth, Martin; Srinivas, Shankar

2010-06-03

Lipid droplets (LD) are organelles with an important role in normal metabolism and disease. The lipid content of embryos has a major impact on viability and development. LD in Drosophila embryos and cultured cell lines have been shown to move and fuse in a microtubule dependent manner. Due to limitations in current imaging technology, little is known about the behaviour of LD in the mammalian embryo. Harmonic generation microscopy (HGM) allows one to image LD without the use of exogenous labels. Adaptive optics can be used to correct aberrations that would otherwise degrade the quality and information content of images. We have built a harmonic generation microscope with adaptive optics to characterise early mouse embryogenesis. At fertilization, LD are small and uniformly distributed, but in the implanting blastocyst, LD are larger and enriched in the invading giant cells of the trophectoderm. Time-lapse studies reveal that LD move continuously and collide but do not fuse, instead forming aggregates that subsequently behave as single units. Using specific inhibitors, we show that the velocity and dynamic behaviour of LD is dependent not only on microtubules as in other systems, but also on microfilaments. We explore the limits within which HGM can be used to study living embryos without compromising viability and make the counterintuitive finding that 16 J of energy delivered continuously over a period of minutes can be less deleterious than an order of magnitude lower energy delivered dis-continuously over a period of hours. LD in pre-implantation mouse embryos show a previously unappreciated complexity of behaviour that is dependent not only on microtubules, but also microfilaments. Unlike LD in other systems, LD in the mouse embryo do not fuse but form aggregates. This study establishes HGM with adaptive optics as a powerful tool for the study of LD biology and provides insights into the photo-toxic effects of imaging embryos.

FT-IR microscopic mappings of early mineralization in chick limb bud mesenchymal cell cultures

NASA Technical Reports Server (NTRS)

Boskey, A. L.; Camacho, N. P.; Mendelsohn, R.; Doty, S. B.; Binderman, I.

1992-01-01

Chick limb bud mesenchymal cells differentiate into chondrocytes and form a cartilaginous matrix in culture. In this study, the mineral formed in different areas within cultures supplemented with 4 mM inorganic phosphate, or 2.5, 5.0, and 10 mM beta-glycerophosphate (beta GP), was characterized by Fourier-transform infrared (FT-IR) microscopy. The relative mineral-to-matrix ratios, and distribution of crystal sizes at specific locations throughout the matrix were measured from day 14 to day 30. The only mineral phase detected was a poorly crystalline apatite. Cultures receiving 4 mM inorganic phosphate had smaller crystals which were less randomly distributed around the cartilage nodules than those in the beta GP-treated cultures. beta GP-induced mineral consisted of larger, more perfect apatite crystals. In cultures receiving 5 or 10 mM beta GP, the relative mineral-to-matrix ratios (calculated from the integrated intensities of the phosphate and amide I bands, respectively) were higher than in the cultures with 4 mM inorganic phosphate or in the in vivo calcified chick cartilage.

Effects of LED lighting during incubation on layer and broiler hatchability, chick quality, stress susceptibility and post-hatch growth.

PubMed

Huth, Jesse C; Archer, Gregory S

2015-12-01

Providing light during incubation has been shown to affect hatchability, but the use of LED lights has not been evaluated. This experiment evaluated the effects of LED lighting during embryogenesis on White Leghorn and commercial broiler eggs. To determine this, two experiments were conducted, the first using White Leghorn eggs (N=3456) and the second using commercial broiler eggs (N=3456) where eggs were incubated 12 h of light and 12 h of darkness (LED) or complete darkness (DARK); the light level was 250 lux. Hatchability, embryo mortality, and chick quality were measured in both studies, and a subset of one of the broiler egg trials were grown out to investigate fear and stress parameters. There was no effect (P>0.05) on hatchability of layer eggs; however, there was a difference (P=0.02) observed in chick quality, with the LED group having more chicks (75.34%) with no defects than the DARK group (56.53%). Broiler eggs exposed to LED light showed an increase in hatchability (90.12%, P=0.03) and an increase in no-defect chick percentage (86.12%, P=0.04) at hatch compared to the DARK chicks (85.76% and 69.43%, respectively). Differences were observed between treatments during the 14 d grow-out. The LED birds had lower (P<0.05) physical asymmetry (0.90±0.05 mm) and heterophil/lymphocyte ratios (0.279±0.021), indicating that they were less susceptible to stress than the DARK birds (1.16±0.07 mm and 0.347±0.021, respectively). There was no difference (P>0.05) observed between treatments in growth, FCR, or fear measures at 14 d. These results indicate that providing LED light during incubation can improve chick quality in both white layer and broiler eggs; however, it only appears to improve hatchability in broilers, which could be related to shell pigmentation. It was also demonstrated that providing LED light during incubation can reduce the stress susceptibility of broilers post-hatch. Utilizing light during incubation may be useful tool for the poultry

Cross-neutralization of antibodies induced by vaccination with Purified Chick Embryo Cell Vaccine (PCECV) against different Lyssavirus species

PubMed Central

Malerczyk, Claudius; Freuling, Conrad; Gniel, Dieter; Giesen, Alexandra; Selhorst, Thomas; Müller, Thomas

2014-01-01

Background: Rabies is a neglected zoonotic disease caused by viruses belonging to the genus lyssavirus. In endemic countries of Asia and Africa, where the majority of the estimated 60,000 human rabies deaths occur, it is mainly caused by the classical rabies virus (RABV) transmitted by dogs. Over the last decade new species within the genus lyssavirus have been identified. Meanwhile 15 (proposed or classified) species exist, including Australian bat lyssavirus (ABLV), European bat lyssavirus (EBLV-1 and -2), Duvenhage virus (DUVV), as well as Lagos bat virus (LBV) and Mokola virus (MOKV) and recently identified novel species like Bokeloh bat lyssavirus (BBLV), Ikoma bat lyssavirus (IKOV) or Lleida bat lyssavirus (LLBV). The majority of these lyssavirus species are found in bat reservoirs and some have caused human infection and deaths. Previous work has demonstrated that Purified Chick Embryo Cell Rabies Vaccine (PCECV) not only induces immune responses against classical RABV, but also elicits cross-neutralizing antibodies against ABLV, EBLV-1 and EBLV-2. Material & Methods: Using the same serum samples as in our previous study, this study extension investigated cross-neutralizing activities of serum antibodies measured by rapid fluorescent focus inhibition test (RFFIT) against selected other non-classical lyssavirus species of interest, namely DUVV and BBLV, as well as MOKV and LBV. Results: Antibodies developed after vaccination with PCECV have neutralizing capability against BBLV and DUVV in the same range as against ABLV and EBLV-1 and -2. As expected, for the phylogenetically more distant species LBV no cross-neutralizing activity was found. Interestingly, 15 of 94 serum samples (16%) with a positive neutralizing antibody titer against RABV displayed specific cross-neutralizing activity (65-fold lower than against RABV) against one specific MOKV strain (Ethiopia isolate), which was not seen against a different strain (Nigeria isolate). Conclusion: Cross

Cross-neutralization of antibodies induced by vaccination with Purified Chick Embryo Cell Vaccine (PCECV) against different Lyssavirus species.

PubMed

Malerczyk, Claudius; Freuling, Conrad; Gniel, Dieter; Giesen, Alexandra; Selhorst, Thomas; Müller, Thomas

2014-01-01

Rabies is a neglected zoonotic disease caused by viruses belonging to the genus lyssavirus. In endemic countries of Asia and Africa, where the majority of the estimated 60,000 human rabies deaths occur, it is mainly caused by the classical rabies virus (RABV) transmitted by dogs. Over the last decade new species within the genus lyssavirus have been identified. Meanwhile 15 (proposed or classified) species exist, including Australian bat lyssavirus (ABLV), European bat lyssavirus (EBLV-1 and -2), Duvenhage virus (DUVV), as well as Lagos bat virus (LBV) and Mokola virus (MOKV) and recently identified novel species like Bokeloh bat lyssavirus (BBLV), Ikoma bat lyssavirus (IKOV) or Lleida bat lyssavirus (LLBV). The majority of these lyssavirus species are found in bat reservoirs and some have caused human infection and deaths. Previous work has demonstrated that Purified Chick Embryo Cell Rabies Vaccine (PCECV) not only induces immune responses against classical RABV, but also elicits cross-neutralizing antibodies against ABLV, EBLV-1 and EBLV-2. Using the same serum samples as in our previous study, this study extension investigated cross-neutralizing activities of serum antibodies measured by rapid fluorescent focus inhibition test (RFFIT) against selected other non-classical lyssavirus species of interest, namely DUVV and BBLV, as well as MOKV and LBV. Antibodies developed after vaccination with PCECV have neutralizing capability against BBLV and DUVV in the same range as against ABLV and EBLV-1 and -2. As expected, for the phylogenetically more distant species LBV no cross-neutralizing activity was found. Interestingly, 15 of 94 serum samples (16%) with a positive neutralizing antibody titer against RABV displayed specific cross-neutralizing activity (65-fold lower than against RABV) against one specific MOKV strain (Ethiopia isolate), which was not seen against a different strain (Nigeria isolate). Cross-neutralizing activities partly correlate with the

Dynamic Properties of Electrotonic Coupling between Cells of Early Xenopus Embryos

PubMed Central

DiCaprio, R. A.; French, A. S.; Sanders, E. J.

1974-01-01

Frequency response functions were measured between the cells of Xenopus laevis embryos during the first two cleavage stages. Linear systems theory was then used to produce electronic models which account for the electrical behavior of the systems. Coupling between the cells may be explained by models which have simple resistive elements joining each cell to its neighbors. The vitelline, or fertilization, membrane which surrounds the embryos has no detectable resistance to the passage of electric current. The electrical properties of the four-cell embryo can only be explained by the existence of individual junctions linking each pair of cells. This arrangement suggests that electrotonic coupling is important in the development of the embryos, at least until the four-cell stage. ImagesFIGURE 5FIGURE 14FIGURE 15 PMID:19431351

Axial mesendoderm refines rostrocaudal pattern in the chick nervous system.

PubMed

Rowan, A M; Stern, C D; Storey, K G

1999-07-01

There has long been controversy concerning the role of the axial mesoderm in the induction and rostrocaudal patterning of the vertebrate nervous system. Here we investigate the neural inducing and regionalising properties of defined rostrocaudal regions of head process/prospective notochord in the chick embryo by juxtaposing these tissues with extraembryonic epiblast or neural plate explants. We localise neural inducing signals to the emerging head process and using a large panel of region-specific neural markers, show that different rostrocaudal levels of the head process derived from headfold stage embryos can induce discrete regions of the central nervous system. However, we also find that rostral and caudal head process do not induce expression of any of these molecular markers in explants of the neural plate. During normal development the head process emerges beneath previously induced neural plate, which we show has already acquired some rostrocaudal character. Our findings therefore indicate that discrete regions of axial mesendoderm at headfold stages are not normally responsible for the establishment of rostrocaudal pattern in the neural plate. Strikingly however, we do find that caudal head process inhibits expression of rostral genes in neural plate explants. These findings indicate that despite the ability to induce specific rostrocaudal regions of the CNS de novo, signals provided by the discrete regions of axial mesendoderm do not appear to establish regional differences, but rather refine the rostrocaudal character of overlying neuroepithelium.

The Potential Role of As-sumo-1 in the Embryonic Diapause Process and Early Embryo Development of Artemia sinica

PubMed Central

Chu, Bing; Yao, Feng; Cheng, Cheng; Wu, Yang; Mei, Yanli; Li, Xuejie; Liu, Yan; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

2014-01-01

During embryonic development of Artemia sinica, environmental stresses induce the embryo diapause phenomenon, required to resist apoptosis and regulate cell cycle activity. The small ubiquitin-related modifier-1 (SUMO), a reversible post-translational protein modifier, plays an important role in embryo development. SUMO regulates multiple cellular processes, including development and other biological processes. The molecular mechanism of diapause, diapause termination and the role of As-sumo-1 in this processes and in early embryo development of Artemia sinica still remains unknown. In this study, the complete cDNA sequences of the sumo-1 homolog, sumo ligase homolog, caspase-1 homolog and cyclin B homolog from Artemia sinica were cloned. The mRNA expression patterns of As-sumo-1, sumo ligase, caspase-1, cyclin B and the location of As-sumo-1 were investigated. SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E proteins were analyzed during different developmental stages of the embryo of A. sinica. Small interfering RNA (siRNA) was used to verify the function of sumo-1 in A. sinica. The full-length cDNA of As-sumo-1 was 476 bp, encoding a 92 amino acid protein. The As-caspases-1 cDNA was 966 bp, encoding a 245 amino-acid protein. The As-sumo ligase cDNA was 1556 bp encoding, a 343 amino acid protein, and the cyclin B cDNA was 739 bp, encoding a 133 amino acid protein. The expressions of As-sumo-1, As-caspase-1 and As-cyclin B were highest at the 10 h stage of embryonic development, and As-sumo ligase showed its highest expression at 0 h. The expression of As-SUMO-1 showed no tissue or organ specificity. Western blotting showed high expression of As-SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E at the 10 h stage. The siRNA caused abnormal development of the embryo, with increased malformation and mortality. As-SUMO-1 is a crucial regulation and modification protein resumption of embryonic diapause and early embryo development of A. sinica. PMID:24404204

Intracellular pH in early Xenopus embryos: its effect on current flow between blastomeres.

PubMed Central

Turin, L; Warner, A E

1980-01-01

1. Electrophysiological techniques were used to monitor the flow of electric current from one cell to the next in Xenopus laevis embryos between the 4-cell and early blastula stages of development. Intracellular pH and blastocoel pH were determined using pH-sensitive micro-electrodes. 2. The resting intracellular pH was 7.74+/-0.02 (S.E. of mean, n = 29); there were no systematic differences between developmental stages. Blastocoel cavity pH was 8.4+/-0.06 (S.E. of mean, n = 10). The intracellular buffer value was 18 m-equiv. H+/pH unit per litre. 3. In embryos treated with bicarbonate buffered Holtfreter solution equilibrated with 100% CO2 the intracellular pH fell to 6.3+/-0.17 (S.D., n = 8). The membrane potential fell and the input resistance increased. The size of the effect on membrane potential and input resistance varied. 4. From the 32-cell stage onwards current flow from one cell to the next was abolished when the intracellular pH fell to below 6.5; the effect was rapid in onset and completely reversible. At cleavage stages of development lowering intracellular pH with CO2 had no effect on current flow from cell to cell. 5. The relationship between intracellular pH and current flow from cell to cell was sigmoid and covered between 0.2 and 0.4 pH units. The pH at which current flow was completely abolished ranged from 6.85 to 6.4. 6. Alterations in extraembryonic pH over the range 5.8-7.5 had no effect on any parameter measured. 7. We conclude that lowering the intracellular pH increases the resistance of both non-junctional junctional membranes. The data do not allow us to extract the pH junctional conductance relationship. 8. Variations in intracellular pH may provide a useful tool for the study of the functional role of direct cell to cell communication in both adult organs and early embryos. PMID:6770084

MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos

USDA-ARS?s Scientific Manuscript database

Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cellfree CD8aa+, CD3_ cells with natural killing activity. Cell-mediated cytotoxicity assay...

Ratio of inner cell mass and trophoblastic cells in demi- and intact pig embryos.

PubMed

Tao, T; Reichelt, B; Niemann, H

1995-07-01

Pig morulae, early blastocysts and blastocysts were microsurgically bisected to produce zona-free demi-embryos or remained nonbisected with or without zona pellucida, and the presence of inner cell mass cells was determined using a differential fluorochrome staining technique. After 24 h of in vitro culture, all demi-embryos were classified into three categories, based on morphological criteria: 1, excellent; 2, fair; and 3, degenerated. The average number of total cells and inner cell mass cells in intact embryos cultured without zona pellucida for 24 h was higher (P < 0.05) than that for those with zona pellucida in morulae and early blastocysts. The percentage of demi-embryos without inner cell mass cells in these different morphological categories was 18.7%, 22.2% and 29.8% for morulae, respectively; 3.8%, 16.7% and 30.8% for early blastocysts, respectively; and 3.7%, 32.0% and 36.4% for blastocysts, respectively. The percentage of demi-embryos without inner cell mass cells was lower (P < 0.01) in demi-embryos classified in category 1 compared with category 3 in early blastocysts and in category 1 compared with categories 2 and 3 in blastocysts. Significant differences in the total number of cells and the number of inner cell mass cells were apparent among the three morphological categories of demi-embryos derived from morulae, early blastocysts and blastocysts. The ratio of total cells to inner cell mass cells was similar among intact pig embryos and the different morphological categories of demi-embryos derived from morulae, early blastocysts and blastocysts, with the exception of that between demi-blastocysts of category 1 and the other groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Copper induces expression and methylation changes of early development genes in Crassostrea gigas embryos.

PubMed

Sussarellu, Rossana; Lebreton, Morgane; Rouxel, Julien; Akcha, Farida; Rivière, Guillaume

2018-03-01

Copper contamination is widespread along coastal areas and exerts adverse effects on marine organisms such as mollusks. In the Pacific oyster, copper induces severe developmental abnormalities during early life stages; however, the underlying molecular mechanisms are largely unknown. This study aims to better understand whether the embryotoxic effects of copper in Crassostrea gigas could be mediated by alterations in gene expression, and the putative role of DNA methylation, which is known to contribute to gene regulation in early embryo development. For that purpose, oyster embryos were exposed to 4 nominal copper concentrations (0.1, 1, 10 and 20 μg L -1 Cu 2+ ) during early development assays. Embryotoxicity was monitored through the oyster embryo-larval bioassay at the D-larva stage 24 h post fertilization (hpf) and genotoxicity at gastrulation 7 hpf. In parallel, the relative expression of 15 genes encoding putative homeotic, biomineralization and DNA methylation proteins was measured at three developmental stages (3 hpf morula stage, 7 hpf gastrula stage, 24 hpf D-larvae stage) using RT-qPCR. Global DNA content in methylcytosine and hydroxymethylcytosine were measured by HPLC and gene-specific DNA methylation levels were monitored using MeDIP-qPCR. A significant increase in larval abnormalities was observed from copper concentrations of 10 μg L -1 , while significant genotoxic effects were detected at 1 μg L -1 and above. All the selected genes presented a stage-dependent expression pattern, which was impaired for some homeobox and DNA methylation genes (Notochord, HOXA1, HOX2, Lox5, DNMT3b and CXXC-1) after copper exposure. While global DNA methylation (5-methylcytosine) at gastrula stage didn't show significant changes between experimental conditions, 5-hydroxymethylcytosine, its degradation product, decreased upon copper treatment. The DNA methylation of exons and the transcript levels were correlated in control samples for HOXA1 but such

Mechanism of age-dependent involution in embryonic chick notochords.

PubMed

Ghanem, E; Cornelissen, M; Thierens, H; De Ridder, L

1996-07-15

To study the possible mechanism of the age-dependent involution of the notochord, isolated mesenchyme-free notochords of chick embryos were cultured in vitro and compared with their counterparts in vivo. Two different aspects were evaluated: (1) DNA synthesis measured by [3H]thymidine incorporation and visualized by autoradiography and (2) cell death quantified by counting the number of pyknotic nuclei. The results demonstrate that [3H]thymidine uptake by notochords shows an age-dependent decrease in vitro as well as in vivo. The number of [3H]thymidine-labelled notochord cells, however, is higher in vitro than in vivo. At the same time, there is an age-dependent increase in pyknosis in the notochord in vivo and in vitro. So, during the aging process, the number of both pyknotic nuclei and of [3H]thymidine-labelled nuclei suggest a high turnover of notochord cells in vitro. From these results, we can conclude that the process of involution in aging notochord seems to be controlled by a programmed intrinsic process, which might be influenced partially by the microenvironment in vivo.

Cell death during the development of the truncus and conus of the chick embryo heart.

PubMed Central

Hurle, J M; Ojeda, J L

1979-01-01

The presence of cell death in the walls of the truncus and conus of the developing chick heart was investigated by a variety of light and electron microscopic techniques. Necrotic areas were observed in the myocardial layer of the truncus and conus and within the mesenchymal cells of the truncoconal ridges and aortopulmonary septum. These necrotic zones appeared first at Stage 25-26 and reached their maximum extent at Stages 29-32 undergoing later progressive disappearance. The morphological changes of the degenerating cells detectable under both transmission and scanning electron microscopy are also reported. The possible role of cell death in the morphogenesis of the truncus and conus is discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 PMID:500497

Ethanol impedes embryo transport and impairs oviduct epithelium.

PubMed

Xu, Tonghui; Yang, Qiuhong; Liu, Ruoxi; Wang, Wenfu; Wang, Shuanglian; Liu, Chuanyong; Li, Jingxin

2016-05-16

Most studies have demonstrated that alcohol consumption is associated with decreased fertility. The aim of this study was to investigate the effects of alcohol on pre-implantation embryo transport and/or early embryo development in the oviduct. We reported here that ethanol concentration-dependently suppressed the spontaneous motility of isolated human oviduct strips (EC50 50±6mM), which was largely attenuated in the present of L-NAME, a classical nitric oxide synthase(NOS) competitive inhibitor. Notably, either acute or chronic alcohol intake delayed egg transport and retarded early development of the embryo in the mouse oviduct, which was largely rescued by co-administration of L-NAME in a acute alcohol intake group but not in chronic alcohol intake group. It is worth mentioning that the oviductal epithelium destruction was verified by scanning electron microscope (SEM) observations in chronic alcohol intake group. In conclusion, alcohol intake delayed egg transport and retarded early development of the embryo in the oviduct by suppressing the spontaneous motility of oviduct and/or impairing oviductal epithelium. These findings suggested that alcohol abuse increases the incident of ectopic pregnancy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Guar meal ameliorates Eimeria tenella infection in broiler chicks.

PubMed

Hassan, Sherif M; El-Gayar, Amal K; Cadwell, David J; Bailey, Christopher A; Cartwright, Aubrey L

2008-10-20

Guar meal contains relatively high levels of saponins, which are known to have antiprotozoal activity and may be effective against coccidiosis. A 2x2 factorial experiment investigated the impact of guar meal (0 or 5%) corn-soy-based starter broiler diets on chicks unchallenged or challenged with Eimeria tenella. At 1 day of age, 120 unsexed RossxRoss broiler chicks were randomly distributed among four treatment groups. Chicks were challenged with 5x10(3) sporulated oocysts of E. tenella in 0.5 ml at 10 days of age by oral gavage. Weekly body weight, body weight gains, feed conversion ratio and mortality rate were recorded for chicks fed from 0 to 21 days of age. Oocysts shed per gram feces were recorded from 6 to 10 days post-challenge. Results showed that challenged chicks fed 0% guar meal had significantly higher oocysts per gram shed in feces than the other groups. No significant differences among treatment groups in mortality rate were observed. Body weights of unchallenged and challenged chicks fed 0% guar meal were significantly higher than those fed 5% guar meal at 2 weeks of age. Results indicated that including 5% guar meal in the diet of chicks challenged with E. tenella decreased oocysts shed per gram feces and prevented bloody diarrhea, but without affects on body weight and feed conversion ratio at 11 days post-challenge.

Quantitative analyses of cell behaviors underlying notochord formation and extension in mouse embryos.

PubMed

Sausedo, R A; Schoenwolf, G C

1994-05-01

Formation and extension of the notochord (i.e., notogenesis) is one of the earliest and most obvious events of axis development in vertebrate embryos. In birds and mammals, prospective notochord cells arise from Hensen's node and come to lie beneath the midline of the neural plate. Throughout the period of neurulation, the notochord retains its close spatial relationship with the developing neural tube and undergoes rapid extension in concert with the overlying neuroepithelium. In the present study, we examined notochord development quantitatively in mouse embryos. C57BL/6 mouse embryos were collected at 8, 8.5, 9, 9.5, and 10 days of gestation. They were then embedded in paraffin and sectioned transversely. Serial sections from 21 embryos were stained with Schiff's reagent according to the Feulgen-Rossenbeck procedure and used for quantitative analyses of notochord extension. Quantitative analyses revealed that extension of the notochord involves cell division within the notochord proper and cell rearrangement within the notochordal plate (the immediate precursor of the notochord). In addition, extension of the notochord involves cell accretion, that is, the addition of cells to the notochord's caudal end, a process that involves considerable cell rearrangement at the notochordal plate-node interface. Extension of the mouse notochord occurs similarly to that described previously for birds (Sausedo and Schoenwolf, 1993 Anat. Rec. 237:58-70). That is, in both birds (i.e., quail and chick) and mouse embryos, notochord extension involves cell division, cell rearrangement, and cell accretion. Thus higher vertebrates utilize similar morphogenetic movements to effect notogenesis.

The effect of dietary betaine in Eimeria acervulina-infected chicks.

PubMed

Matthews, J O; Southern, L L

2000-01-01

Two experiments were conducted to evaluate the effect of dietary betaine in broiler chicks with either chronic (CHR; 2.5 x 10(5) sporulated oocysts on Day 1, 4, 7, and 10) or acute (ACT; 1.0 x 10(6) sporulated oocysts on Day 1) Eimeria acervulina infections. Three hundred (Experiment 1) or 600 (Experiment 2), 4-d-old male chicks were used in the 14-d experiments. In both experiments, a 2 x 3 factorial arrangement of treatments was used: two levels of betaine (0 or 0.075%) and three levels of coccidiosis infection (uninfected, CHR, or ACT). Each treatment was replicated five (Experiment 1) or 10 (Experiment 2) times with 10 chicks per replicate. In Experiment 1, the ACT infection decreased (P < 0.01) average daily gain and gain:feed, and the CHR infection decreased (P < 0.02) average daily gain. The ACT and CHR infections decreased (P < 0.06) Day 7 plasma carotenoids and Day 14 plasma total protein, and the ACT infection also decreased (P < 0.06) Day 7 plasma total protein. Average daily gain and Day 7 plasma total protein were increased in CHR chicks fed betaine but were decreased in uninfected chicks fed betaine (CHR x betaine; P < 0.09). Chicks fed betaine had decreased (P < 0.06) Day 7 plasma carotenoids. In Experiment 2 the CHR and ACT infections decreased (P < 0.01) average daily gain, average daily feed intake, grain:feed ratio, Days 7 and 14 plasma carotenoids, and Day 7 plasma total protein. Chicks fed betaine had increased (P < 0.07) average daily gains, gain:feed ratios, and lesion scores. Day 14 plasma carotenoids and plasma total protein were decreased in uninfected chicks fed betaine but were increased in CHR chicks fed betaine (CHR x betaine; P < 0.04); plasma carotenoids also were increased in ACT chicks fed betaine (ACT x betaine; P < 0.05). Betaine did not consistently affect growth performance, plasma constituents, or lesion score in CHR or ACT coccidiosis-infected chicks.

Single cell imaging of the chick retina with adaptive optics.

PubMed

Headington, Kenneth; Choi, Stacey S; Nickla, Debora; Doble, Nathan

2011-10-01

The chick eye is extensively used as a model in the study of myopia and its progression; however, analysis of the photoreceptor mosaic has required the use of excised retina due to the uncorrected optical aberrations in the lens and cornea. This study implemented high resolution adaptive optics (AO) retinal imaging to visualize the chick cone mosaic in vivo. The New England College of Optometry (NECO) AO fundus camera was modified to allow high resolution in vivo imaging on two 6-week-old White Leghorn chicks (Gallus gallus domesticus)-labeled chick A and chick B. Multiple, adjacent images, each with a 2.5(o) field of view, were taken and subsequently montaged together. This process was repeated at varying retinal locations measured from the tip of the pecten. Automated software was used to determine the cone spacing and density at each location. Voronoi analysis was applied to determine the packing arrangement of the cones. In both chicks, cone photoreceptors were clearly visible at all retinal locations imaged. Cone densities measured at 36(o) nasal-12(o) superior retina from the pecten tip for chick A and 40(o) nasal-12(o) superior retina for chick B were 21,714 ± 543 and 26,105 ± 653 cones/mm(2) respectively. For chick B, a further 11 locations immediately surrounding the pecten were imaged, with cone densities ranging from 20,980 ± 524 to 25,148 ± 629 cones/mm(2). In vivo analysis of the cone density and its packing characteristics are now possible in the chick eye through AO imaging, which has important implications for future studies of myopia and ocular disease research.

The effects of the early uterine environment on the subsequent development of embryo and fetus.

PubMed

Barnes, F L

2000-01-15

Synchrony between the embryo and the uterine endometrium is essential for the establishment of pregnancy and birth in people and livestock. When asynchronous conditions occur a variety of complication result that include failure of the embryo to implant, early embryonic mortality, retarded development and growth, and accelerated development and growth. These complications all appear to be induced within the first week of embryo development and not withstanding the immediate endpoint of large or small size at birth, may alter the course of development throughout the life of the animal. Progesterone appears to play a causative role in establishing the abnormal growth of the fetus by decelerating or accelerating embryonic development. This may act through increasing the transport of blood born growth factors into the uterine lumen or by stimulating the release of growth factors from the endometrium directly. It can not be ruled out that progesterone mediated abundance of, or absence of, appropriate nutrition may bring about the same lifelong outcome. In vitro culture situations that include serum and/or co-culture can also bring about these abnormalities of growth. It is hypothesized that exposure to growth factors "out of phase" may result in an irreversible induction of abnormal development. The described abnormalities that occur in sheep and cattle have not yet been described for children resulting from IVF.

Stress Induces AMP-Dependent Loss of Potency Factors Id2 and Cdx2 in Early Embryos and Stem Cells

PubMed Central

Xie, Yufen; Awonuga, Awoniyi; Liu, Jian; Rings, Edmond; Puscheck, Elizabeth Ella

2013-01-01

The AMP-activated protein kinase (AMPK) mediates rapid, stress-induced loss of the inhibitor of differentiation (Id)2 in blastocysts and trophoblast stem cells (TSC), and a lasting differentiation in TSC. However, it is not known if AMPK regulates other potency factors or regulates them before the blastocyst stage. The caudal-related homeodomain protein (Cdx)2 is a regulatory gene for determining TSC, the earliest placental lineage in the preimplantation mouse embryo, but is expressed in the oocyte and in early cleavage stage embryos before TSC arise. We assayed the expression of putative potency-maintaining phosphorylated Cdx2 ser60 in the oocyte, two-cell stage embryo, blastocyst, and in TSC. We studied the loss of Cdx2 phospho ser60 expression induced by hyperosmolar stress and its underlying mechanisms. Hyperosmolar stress caused rapid loss of nuclear Cdx2 phospho ser60 and Id2 in the two-cell stage embryo by 0.5 h. Stress-induced Cdx2 phospho ser60 and Id2 loss is reversed by the AMPK inhibitor compound C and is induced by the AMPK agonist 5-amino-1-β-d-ribofuranosyl-imidazole-4-carboxamide in the absence of stress. In the two-cell stage embryo and TSC hyperosmolar, stress caused AMPK-mediated loss of Cdx2 phospho ser60 as detected by immunofluorescence and immunoblot. We propose that AMPK may be the master regulatory enzyme for mediating stress-induced loss of potency as AMPK is also required for stress-induced loss of Id2 in blastocysts and TSC. Since AMPK mediates potency loss in embryos and stem cells it will be important to measure, test mechanisms for, and manage the AMPK function to optimize the stem cell and embryo quality in vitro and in vivo. PMID:23316940

P-TEFb, the Super Elongation Complex and Mediator Regulate a Subset of Non-paused Genes during Early Drosophila Embryo Development

PubMed Central

Dahlberg, Olle; Shilkova, Olga; Tang, Min; Holmqvist, Per-Henrik; Mannervik, Mattias

2015-01-01

Positive Transcription Elongation Factor b (P-TEFb) is a kinase consisting of Cdk9 and Cyclin T that releases RNA Polymerase II (Pol II) into active elongation. It can assemble into a larger Super Elongation Complex (SEC) consisting of additional elongation factors. Here, we use a miRNA-based approach to knock down the maternal contribution of P-TEFb and SEC components in early Drosophila embryos. P-TEFb or SEC depletion results in loss of cells from the embryo posterior and in cellularization defects. Interestingly, the expression of many patterning genes containing promoter-proximal paused Pol II is relatively normal in P-TEFb embryos. Instead, P-TEFb and SEC are required for expression of some non-paused, rapidly transcribed genes in pre-cellular embryos, including the cellularization gene Serendipity-α. We also demonstrate that another P-TEFb regulated gene, terminus, has an essential function in embryo development. Similar morphological and gene expression phenotypes were observed upon knock down of Mediator subunits, providing in vivo evidence that P-TEFb, the SEC and Mediator collaborate in transcription control. Surprisingly, P-TEFb depletion does not affect the ratio of Pol II at the promoter versus the 3’ end, despite affecting global Pol II Ser2 phosphorylation levels. Instead, Pol II occupancy is reduced at P-TEFb down-regulated genes. We conclude that a subset of non-paused, pre-cellular genes are among the most susceptible to reduced P-TEFb, SEC and Mediator levels in Drosophila embryos. PMID:25679530

Brood size can influence maternal behaviour and chick's development in precocial birds.

PubMed

Aigueperse, Nadège; Pittet, Florent; de Margerie, Emmanuel; Nicolle, Céline; Houdelier, Cécilia; Lumineau, Sophie

2017-05-01

Mothers have a crucial influence on offspring development. Variations of maternal behaviour can be due to numerous parameters, for instance costs are related to the size of a brood/litter, which in turn can influence the level of mothers' investment in each offspring. Here we investigated the influence of brood size on the behaviour of Japanese quail mothers and chicks during the mothering period and on offspring development. We compared two types of broods: small broods of three chicks (N=9) and large broods of six chicks (N=9). Behavioural tests assessed chicks' social and emotional traits. Mothers of large broods emitted more maternal vocalisations at the beginning of the mothering period, but at the end they assumed more non-covering postures and trampled chicks more than mothers of small broods. Chicks in large broods huddled up more whereas chicks in small broods rested alone more frequently. Moreover, the social motivation of chicks in large broods was higher than that of chicks in small broods, although their emotional reactivity levels were similar. Our results evidence the importance of brood size for maintaining family cohesion and the influence of brood size on chicks' interactions with their siblings. We evaluated the influence of mothers and siblings on chicks' behavioural development. Copyright © 2017 Elsevier B.V. All rights reserved.

[Establishment of sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo].

PubMed

Jiang, Hua; Feng, You-Ji; Xie, Yi; Han, Jin-Lan; Wang, Zack; Chen, Tong

2008-10-14

To establish a sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo. Human embryonic stem were (hESCs) were cultured on the mouse embryo fibroblasts and then were induced to differentiate to form three-dimensional EB. The hEBs were cultured in media containing various angiogenesis-related factors: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), endostatin, angiostatin, and platelet factor (PF)-4 of different concentrations for 3 days to observe the sprouting of the hEBs. 3, 3, 3', 3'-tetramethylindo-carbocyanine perchlorate labeled acetylated low density lipoprotein (Dil-AcLDL) was added onto the hEBs foe 4 h Immunofluorescence assay was used to observe if Dil-AcLDL was absorbed and if CD31 was expressed so as to determine the existence of embryonic endothelial cells in the sprouting structures. The ideal culturing condition was analyzed. The differentiated EBs formed sprouting structures in the collagen I matrix containing VEGF and FGF. The sprouts among individual EBs were able to link to each other and form vascular network-like structures. In the presence of VEGF and FGF, the sprouts branching from the EBs assimilated Dil-AcLDL, expressed CD31 and formed a 3-dimensional cylindrical organization. The concentrations of growth factors ideally stimulating sprouting growth were 100 ng/ml of VEGF and 50 ng/ml of FGF. The networks among the EBs were abolished by the angiostatin, endostatin, and PF4. The sprouting from hEBs accumulates embryonic endothelial cells and the sprouting network-like structures are indeed endothelial in nature. Inducing of sprouting EBs is an ideal model that mimics early embryonic vasculogenesis in humans.

The immunologic and antioxidant effects of L-phenylalanine on the uterine implantation of mice embryos during early pregnancy.

PubMed

Dong, Yulan; Bai, Yongping; Liu, Guanhui; Wang, Zixu; Cao, Jing; Chen, Yaoxing; Yang, Hongliang

2014-10-01

L-phenylalanine (L-PHE) is a synthetic precursor of catecholamines. Because it cannot be synthesised by an organism, it must be absorbed from the environment. Despite the wide use of L-PHE, whether L-PHE has a negative impact on embryo implantation and development is poorly understood. This study attempted to determine the roles of L-PHE in embryo implantation and development and in the immune response and antioxidant status of the uterus in early pregnancy mice injected intraperitoneally with 320 mg/kg L-PHE. The embryo number of treated mice decreased by 57.6%, and the size of their embryos was reduced by 2.8% (P⟩0.05) along the long diameter and 11.9% (P⟨0.05) along the short diameter at E9 compared with control mice. In addition, L-PHE significantly suppressed B lymphocyte proliferation. L-PHE increased IL-2 secretion but decreased the IL-4 concentration, thereby up-regulating the ratio of IL-2/IL-4 to 1.37-8.45. An analysis of the oxidant and antioxidant status showed that, compared with the control mice, the level of superoxide dismutase activity decreased by 21.54-39.94% and the glutathione peroxidase activity decreased by 15.27-18.96% among the L-PHE-treated mice at E1-E9. However, the malonaldehyde content increased by 14.29%-90.11% among the L-PHE-treated mice. Therefore, L-PHE impaired embryo implantation by disrupting cytokine-based immunity and oxidative stress in the uterus.

California gull chicks raised near colony edges have elevated stress levels

USGS Publications Warehouse

Herring, Garth; Ackerman, Joshua T.

2011-01-01

Coloniality in nesting birds represents an important life history strategy for maximizing reproductive success. Birds nesting near the edge of colonies tend to have lower reproductive success than individuals nesting near colony centers, and offspring of edge-nesting parents may be impaired relative to those of central-nesting parents. We used fecal corticosterone metabolites in California gull chicks (Larus californicus) to examine whether colony size or location within the colony influenced a chick's physiological condition. We found that chicks being raised near colony edges had higher fecal corticosterone metabolite concentrations than chicks raised near colony centers, but that colony size (ranging from 150 to 11,554 nests) had no influence on fecal corticosterone levels. Fecal corticosterone metabolite concentrations also increased with chick age. Our results suggest that similarly aged California gull chicks raised near colony edges may be more physiologically stressed, as indicated by corticosterone metabolites, than chicks raised near colony centers.

Effect of mothering on the spatial exploratory behavior of quail chicks.

PubMed

de Margerie, E; Peris, A; Pittet, F; Houdelier, C; Lumineau, S; Richard-Yris, M-A

2013-04-01

Previous maternal deprivation experiments demonstrated that absence of maternal care impacts the behavioral development of young animals. Here we assessed the influence of the presence of a mothering hen on the spatial exploration of Japanese quail chicks, after the mothering period. Brooded and nonbrooded chicks were placed in a novel environment containing feeding troughs. The distribution of chicks and their inter-individual distances were measured during repeated tests. Brooded chicks exhibited a higher ability to disperse, thereby progressively exploiting larger surfaces and gaining access to food more easily. The fact that exploration by nonbrooded chicks was delayed suggests a deficit in their exploratory motivation and/or spatial skills. We hypothesize that brooded chicks experienced the constraint to follow the mothering hen, and to adapt to frequent reconfigurations of their environment. The lack of this variability in the environment of nonbrooded chicks could have reduced adaptability of their spatial behavior. Copyright © 2012 Wiley Periodicals, Inc.

Catching-up but telomere loss: half-opening the black box of growth and ageing trade-off in wild king penguin chicks.

PubMed

Geiger, Sylvie; Le Vaillant, Maryline; Lebard, Thomas; Reichert, Sophie; Stier, Antoine; LE Maho, Yvon; Criscuolo, Francois

2012-03-01

One of the reasons for animals not to grow as fast as they potentially could is that fast growth has been shown to be associated with reduced lifespan. However, we are still lacking a clear description of the reality of growth-dependent modulation of ageing mechanisms in wild animals. Using the particular growth trajectory of small king penguin chicks naturally exhibiting higher-than-normal growth rate to compensate for the winter break, we tested whether oxidative stress and telomere shortening are related to growth trajectories. Plasma antioxidant defences, oxidative damage levels and telomere length were measured at the beginning and at the end of the post-winter growth period in three groups of chicks (small chicks, which either passed away or survived the growth period, and large chicks). Small chicks that died early during the growth period had the highest level of oxidative damage and the shortest telomere lengths prior to death. Here, we show that small chicks that grew faster did it at the detriment of body maintenance mechanisms as shown by (i) higher oxidative damage and (ii) accelerated telomere loss. Our study provides the first evidence for a mechanistic link between growth and ageing rates under natural conditions. © 2011 Blackwell Publishing Ltd.

Transcriptome analysis of PCOS arrested 2-cell embryos.

PubMed

Lu, Cuiling; Chi, Hongbin; Wang, Yapeng; Feng, Xue; Wang, Lina; Huang, Shuo; Yan, Liying; Lin, Shengli; Liu, Ping; Qiao, Jie

2018-06-18

In an attempt to explore the early developmental arrest in embryos from polycystic ovarian syndrome (PCOS) patients, we sequenced the transcriptome profiles of PCOS arrested 2-cell embryos, non-PCOS arrested 2-cell embryos and non-arrested 2-cell embryos using single-cell RNA-Seq technique. Differential expression analysis was performed using the DEGSeq R package. Gene Ontology (GO) enrichment was analyzed using the GOseq R package. Data revealed 62 differentially expressed genes between non-PCOS arrested and PCOS arrested embryos and 2217 differentially expressed genes between PCOS arrested and non-arrested 2-cell embryos. A total of 49 differently expressed genes (DEGs) were annotated with GO terms in the up-regulated genes between PCOS arrested and non-PCOS arrested embryos after GO enrichment. A total of 29 DEGs were annotated with GO terms in the down-regulated genes between PCOS arrested and non-arrested 2-cell embryos after GO enrichment. These data can provide a reference for screening specific genes involved in the arrest of PCOS embryos.

Spatial distribution of the capacity to initiate a secondary embryo in the 32-cell embryo of Xenopus laevis.

PubMed

Kageura, H

1990-12-01

To examine the spatial distribution of dorsal determinants in the early embryos of Xenopus laevis, individual cells from the 32-cell embryo were transplanted into the same tier of the ventral side of a synchronous recipient. Their abilities to initiate a secondary embryo were measured by the incidence of secondary embryos and by the length of the secondary axis relative to the primary embryo. The ability was found to be localized in all cells (A1, B1, C1, and D1) of the dorsal most column and in the vegetal cells (C2 and D2) of the dorsolateral column. Transplanted C1 (subequatorial) cells caused the highest incidence of a secondary embryo and the average relative length of the secondary embryo was also greatest. Effectiveness decreased in the order: D1, B1, D2, C2, and A1. When these results were compared with Dale and Slack's fate map of the 32-cell embryo, it was concluded that the distribution of dorsal determinants is unique and does not coincide with the prospective regions for any tissues, though it is somewhat similar to the prospective region of dorsal endoderm or notochord. From these results it seems that dorsal determinants do not determine a particular tissue in an embryo but rather the "dorsal" region of an embryo.

Early life sensory ability-ventilatory responses of thornback ray embryos (Raja clavata) to predator-type electric fields.

PubMed

Ball, Rachel Emma; Oliver, Matthew Kenneth; Gill, Andrew Bruce

2016-07-01

Predator avoidance is fundamental for survival and it can be particularly challenging for prey animals if physical movement away from a predatory threat is restricted. Many sharks and rays begin life within an egg capsule that is attached to the sea bed. The vulnerability of this sedentary life stage is exacerbated in skates (Rajidae) as the compulsory ventilatory activity of embryos makes them conspicuous to potential predators. Embryos can reduce this risk by mediating ventilatory activity if they detect the presence of a predator using an acute electrosense. To determine how early in embryonic life predator elicited behavioral responses can occur, the reactions of three different age groups (1/3 developed, 2/3 developed, and near hatching) of embryonic thornback rays Raja clavata were tested using predator-type electric field stimuli. Egg capsules were exposed to continuous or intermittent stimuli in order to assess varying predator-type encounter scenarios on the ventilatory behavior of different developmental stages. All embryos reacted with a "freeze response" following initial electric field (E-field) exposure, ceasing ventilatory behavior in response to predator presence, demonstrating electroreceptive functionality for the first time at the earliest possible stage in ontogeny. This ability coincided with the onset of egg ventilatory behavior and may represent an effective means to enhance survival. A continuous application of stimuli over time revealed that embryos can adapt their behavior and resume normal activity, whereas when presented intermittently, the E-field resulted in a significant reduction in overall ventilatory activity across all ages. Recovery from stimuli was significantly quicker in older embryos, potentially indicative of the trade-off between avoiding predation and adequate respiration. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 721-729, 2016. © 2015 Wiley Periodicals, Inc.

Deep cytoplasmic rearrangements in ventralized Xenopus embryos

NASA Technical Reports Server (NTRS)

Brown, E. E.; Denegre, J. M.; Danilchik, M. V.

1993-01-01

Following fertilization in Xenopus, dramatic rearrangements of the egg cytoplasm relocalize maternally synthesized egg components. During the first cell cycle the vegetal yolk mass rotates relative to the egg surface, toward the sperm entry point (SEP) (J. P. Vincent, G. F. Oster, and J. C. Gerhart, 1986, Dev. Biol. 113, 484-500), while concomitant deep cytoplasmic rearrangements occur in the animal hemisphere (M. V. Danilchik and J. M. Denegre, 1991, Development 111, 845-856). In this paper we examine the role of vegetal yolk mass rotation in producing the animal cytoplasmic rearrangements. We inhibited rotation by uv-irradiating embryos during the first cell cycle, a treatment that yields an extremely ventralized phenotype. Both uv-irradiated embryos and unirradiated control embryos show cytoplasmic rearrangements in the animal hemisphere during the first cell cycle. Cytoplasmic rearrangements on the SEP side of the embryo associated with the path of the sperm pronucleus, plus a swirl on the anti-SEP (dorsal) side, are seen, whether or not yolk mass rotation has occurred. This result suggests a role for the expanding sperm aster in directing animal hemisphere cytoplasmic movements. In unirradiated control embryos the anti-SEP (dorsal) swirl is larger than that in uv-irradiated embryos and often extends into the vegetal hemisphere, consistent with the animal cytoplasm having been pulled dorsally and vegetally by the sliding vegetal yolk mass. Thus the yolk mass rotation may normally enhance the dorsalward cytoplasmic movement, begun by the sperm aster, enough to induce normal axis formation. We extended our observations of unirradiated control and uv-irradiated embryos through early cleavages. The vegetal extent of the anti-SEP (dorsal) swirl pattern seen in control embryos persists through the early cleavage period, such that labeled animal cytoplasm extends deep into dorsal third-tier blastomeres at the 32-cell stage. Significantly, in uv-irradiated embryos

Effect of hen age and maternal vitamin D source on performance, hatchability, bone mineral density, and progeny in vitro early innate immune function.

PubMed

Saunders-Blades, J L; Korver, D R

2015-06-01

The metabolite 25-hydroxy vitamin D3 (25-OHD) can complement or replace vitamin D3 in poultry rations, and may influence broiler production and immune function traits. The effect of broiler breeder dietary 25-OHD on egg production, hatchability, and chick early innate immune function was studied. We hypothesized that maternal dietary 25-OHD would support normal broiler breeder production and a more mature innate immune system of young chicks. Twenty-three-week-old Ross 308 hens (n=98) were placed in 4 floor pens and fed either 2,760 IU vitamin D3 (D) or 69 μg 25-OHD/kg feed. Hen weights were managed according to the primary breeder management guide. At 29 to 31 wk (Early), 46 to 48 wk (Mid), and 61 to 63 wk (Late), hens were artificially inseminated and fertile eggs incubated and hatched. Chicks were placed in cages based on maternal treatment and grown to 7 d age. Innate immune function and plasma 25-OHD were assessed at 1 and 4 d post-hatch on 15 chicks/treatment. Egg production, hen BW, and chick hatch weight were not affected by diet (P>0.05). Total in vitro Escherichia coli (E. coli) killing by 25-OHD chicks was greater than the D chicks at 4 d for the Early and Mid hatches, and 1 and 4 d for the Late hatch. This can be partly explained by the 25-OHD chicks from the Late hatch also having a greater E. coli phagocytic capability. No consistent pattern of oxidative burst response was observed. Chicks from the Mid hatch had greater percent phagocytosis, phagocytic capability, and E. coli killing than chicks from Early and Late hatches. Overall, maternal 25-OHD increased hatchability and in vitro chick innate immunity towards E. coli. Regardless of treatment, chicks from Late and Early hens had weaker early innate immune responses than chicks from Mid hens. The hen age effect tended to be the greatest factor influencing early chick innate immunity, but maternal 25-OHD also increased several measures relative to D. © 2015 Poultry Science Association Inc.

Climatic factors affecting quantity and quality grade of in vivo derived embryos of cattle.

PubMed

Chinchilla-Vargas, Josué; Jahnke, Marianna M; Dohlman, Tyler M; Rothschild, Max F; Gunn, Patrick J

2018-05-01

The present study investigated the effects of climatic variables on the quality grade and quantity of in vivo derived cattle embryos in the Midwestern United States. Climatic information included greatest and least daily temperature, average daily wind speed and average temperature-humidity index for each of the 765 records. The response variables included the number of ovarian structures, viable embryos, quality grade 1 embryos, quality grade 2 embryos, quality grade 3 embryos, freezable embryos (sum of quality grade 1 and quality grade 2 embryos), transferable embryos (sum of quality grade 1-3 embryos), degenerate embryos and unfertilized ova. Measures for variables among the breeds of donors and sires grouped by geographical origin were compared. A negative effect of greater temperatures during the early embryonic development stage tended (P < 0.10) to be associated with a decrease in the quality of embryos recovered. Interestingly, the greater the Temperature-Humidity Index (THI) during the early ovarian antral follicular development stage 40-45 days prior to ovulation was associated with a tendency for greater numbers of total number of freezable and transferable embryos recovered per uterine flushing (P < 0.10). Increased wind speed at the early antral follicular phase 40-45 days prior to ovulation was associated with an increase in the percentage of quality grade 1 embryos recovered (P < 0.05). Wind speed during the estrous synchronization period was also associated with a lesser number of embryos recovered (P < 0.05). This retrospective study confirms that climatic variables have significant effects on the in vivo production of cattle embryos and that wind speed should be considered in future analyses of factors affecting embryo quality. Copyright © 2018 Elsevier B.V. All rights reserved.

Social predisposition dependent neuronal activity in the intermediate medial mesopallium of domestic chicks (Gallus gallus domesticus).

PubMed

Mayer, Uwe; Rosa-Salva, Orsola; Lorenzi, Elena; Vallortigara, Giorgio

2016-09-01

Species from phylogenetically distant animal groups, such as birds and primates including humans, share early experience-independent social predispositions that cause offspring, soon after birth, to attend to and learn about conspecifics. One example of this phenomenon is provided by the behaviour of newly-hatched visually-naïve domestic chicks that preferentially approach a stimulus resembling a conspecific (a stuffed fowl) rather than a less naturalistic object (a scrambled version of the stuffed fowl). However, the neuronal mechanisms underlying this behaviour are mostly unknown. Here we analysed chicks' brain activity with immunohistochemical detection of the transcription factor c-Fos. In a spontaneous choice test we confirmed a significant preference for approaching the stuffed fowl over a texture fowl (a fowl that was cut in small pieces attached to the sides of a box in scrambled order). Comparison of brain activation of a subgroup of chicks that approached either one or the other stimulus revealed differential activation in an area relevant for imprinting (IMM, intermediate medial mesopallium), suggesting that a different level of plasticity is associated with approach to naturalistic and artificial stimuli. c-Fos immunoreactive neurons were present also in the intermediate layers of the optic tectum (a plausible candidate for processing early social predispositions) showing a trend similar to the results for the IMM. Copyright © 2016 Elsevier B.V. All rights reserved.

Enhance beef cattle improvement by embryo biotechnologies.

PubMed

Wu, B; Zan, L

2012-10-01

Embryo biotechnology has become one of the prominent high businesses worldwide. This technology has evolved through three major changes, that is, traditional embryo transfer (in vivo embryo production by donor superovulation), in vitro embryo production by ovum pick up with in vitro fertilization and notably current cloning technique by somatic cell nuclear transfer and transgenic animal production. Embryo biotechnology has widely been used in dairy and beef cattle industry and commercial bovine embryo transfer has become a large international business. Currently, many developed biotechnologies during the period from early oocyte stage to pre-implantation embryos can be used to create new animal breeds and accelerate genetic progression. Based on recent advances in embryo biotechnologies and authors current studies, this review will focus on a description of the application of this technology to beef cattle improvement and discuss how to use this technology to accelerate beef cattle breeding and production. The main topics of this presentation include the following: (i) how to increase calf production numbers from gametes including sperm and oocyte; (ii) multiple ovulation and embryo transfer breeding schemes; (iii) in vitro fertilization and intracytoplasm sperm injection in bovine; (iv) pronuclear development and transgenic animals; (v) sex selection from sperm and embryos; (vi) cloning and androgenesis; (vii) blastocyst development and embryonic stem cells; (viii) preservation of beef cattle genetic resources; and (ix) conclusions. © 2011 Blackwell Verlag GmbH.

Recognition of the CDEI motif GTCACATG by mouse nuclear proteins and interference with the early development of the mouse embryo.

PubMed Central

Blangy, A; Léopold, P; Vidal, F; Rassoulzadegan, M; Cuzin, F

1991-01-01

We have reported previously (1) two unexpected consequences of the microinjection into fertilized mouse eggs of a recombinant plasmid designated p12B1, carrying a 343 bp insert of non-repetitive mouse DNA. Injected at very low concentrations, this plasmid could be established as an extrachromosomal genetic element. When injected in greater concentration, an early arrest of embryonic development resulted. In the present work, we have studied this toxic effect in more detail by microinjecting short synthetic oligonucleotides with sequences from the mouse insert. Lethality was associated with the nucleotide sequence GTCACATG, identical with the CDEl element of yeast centromeres. Development of injected embryos was arrested between the one-cell and the early morula stages, with abnormal structures and DNA contents. Electrophoretic mobility shift and DNAse foot-printing assays demonstrated the binding of mouse nuclear protein(s) to the CDEl-like box. Base changes within the CDEl sequence prevented both the toxic effects in embryos and the formation of protein complex in vitro, suggesting that protein binding at such sites in chromosomal DNA plays an important role in early development. Images PMID:1766880

Toxicity and cardiac effects of carbaryl in early developing zebrafish (Danio rerio) embryos

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

Lin, C.C.; Hui, Michelle N.Y.; Cheng, S.H. E-mail: bhcheng@cityu.edu.hk

2007-07-15

Carbaryl, an acetylcholinesterase inhibitor, is known to be moderately toxic to adult zebrafish and has been reported to cause heart malformations and irregular heartbeat in medaka. We performed experiments to study the toxicity of carbaryl, specifically its effects on the heart, in early developing zebrafish embryos. LC50 and EC50 values for carbaryl at 28 h post-fertilization were 44.66 {mu}g/ml and 7.52 {mu}g/ml, respectively, and 10 {mu}g/ml carbaryl was used in subsequent experiments. After confirming acetylcholinesterase inhibition by carbaryl using an enzymatic method, we observed red blood cell accumulation, delayed hatching and pericardial edema, but not heart malformation as described inmore » some previous reports. Our chronic exposure data also demonstrated carbaryl-induced bradycardia, which is a common effect of acetylcholinesterase inhibitors due to the accumulation of acetylcholine, in embryos from 1 day post-fertilization (dpf) to 5 dpf. The distance between the sinus venosus, the point where blood enters the atrium, and the bulbus arteriosus, the point where blood leaves the ventricle, indicated normal looping of the heart tube. Immunostaining of myosin heavy chains with the ventricle-specific antibody MF20 and the atrium-specific antibody S46 showed normal development of heart chambers. At the same time, acute exposure resulted in carbaryl-induced bradycardia. Heart rate dropped significantly after a 10-min exposure to 100 {mu}g/ml carbaryl but recovered when carbaryl was removed. The novel observation of carbaryl-induced bradycardia in 1- and 2-dpf embryos suggested that carbaryl affected cardiac function possibly through an alternative mechanism other than acetylcholinesterase inhibition such as inhibition of calcium ion channels, since acetylcholine receptors in zebrafish are not functional until 3 dpf. However, the exact nature of this mechanism is currently unknown, and thus further studies are required.« less

The "waiting period" of sensory and motor axons in early chick hindlimb: its role in axon pathfinding and neuronal maturation.

PubMed

Wang, G; Scott, S A

2000-07-15

During embryonic development motor axons in the chick hindlimb grow out slightly before sensory axons and wait in the plexus region at the base of the limb for approximately 24 hr before invading the limb itself (Tosney and Landmesser, 1985a). We have investigated the role of this waiting period by asking, Is the arrest of growth cones in the plexus region a general property of both sensory and motor axons? Why do axons wait? Does eliminating the waiting period affect the further development of motor and sensory neurons? Here we show that sensory axons, like motor axons, pause in the plexus region and that neither sensory nor motor axons require cues from the other population to wait in or exit from the plexus region. By transplanting older or younger donor limbs to host embryos, we show that host axons innervate donor limbs on a schedule consistent with the age of the grafted limbs. Thus, axons wait in the plexus region for maturational changes to occur in the limb rather than in the neurons themselves. Both sensory and motor axons innervate their appropriate peripheral targets when the waiting period is eliminated by grafting older donor limbs. Therefore, axons do not require a prolonged period in the plexus region to sort out and project appropriately. Eliminating the waiting period does, however, accelerate the onset of naturally occurring cell death, but it does not enhance the development of central projections or the biochemical maturation of sensory neurons.

Myosin-1 inhibition by PClP affects membrane shape, cortical actin distribution and lipid droplet dynamics in early Zebrafish embryos

PubMed Central

Gupta, Prabuddha; Martin, René; Knölker, Hans-Joachim; Nihalani, Deepak; Kumar Sinha, Deepak

2017-01-01

Myosin-1 (Myo1) represents a mechanical link between the membrane and actin-cytoskeleton in animal cells. We have studied the effect of Myo1 inhibitor PClP in 1–8 cell Zebrafish embryos. Our results indicate a unique involvement of Myo1 in early development of Zebrafish embryos. Inhibition of Myo1 (by PClP) and Myo2 (by Blebbistatin) lead to arrest in cell division. While Myo1 isoforms appears to be important for both the formation and the maintenance of cleavage furrows, Myo2 is required only for the formation of furrows. We found that the blastodisc of the embryo, which contains a thick actin cortex (~13 μm), is loaded with cortical Myo1. Myo1 appears to be crucial for maintaining the blastodisc morphology and the actin cortex thickness. In addition to cell division and furrow formation, inhibition of Myo1 has a drastic effect on the dynamics and distribution of lipid droplets (LDs) in the blastodisc near the cleavage furrow. All these results above are effects of Myo1 inhibition exclusively; Myo2 inhibition by blebbistatin does not show such phenotypes. Therefore, our results demonstrate a potential role for Myo1 in the maintenance and formation of furrow, blastodisc morphology, cell-division and LD organization within the blastodisc during early embryogenesis. PMID:28678859

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

PubMed

Ipek, A; Sozcu, A

2017-10-01

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

Colour preferences and colour vision in poultry chicks.

PubMed

Ham, A D; Osorio, D

2007-08-22

The dramatic colours of biological communication signals raise questions about how animals perceive suprathreshold colour differences, and there are long-standing questions about colour preferences and colour categorization by non-human species. This study investigates preferences of foraging poultry chicks (Gallus gallus) as they peck at coloured objects. Work on colour recognition often deals with responses to monochromatic lights and how animals divide the spectrum. We used complementary colours, where the intermediate is grey, and related the chicks' choices to three models of the factors that may affect the attractiveness. Two models assume that attractiveness is determined by a metric based on the colour discrimination threshold either (i) by chromatic contrast against the background or (ii) relative to an internal standard. An alternative third model is that categorization is important. We tested newly hatched and 9-day-old chicks with four pairs of (avian) complementary colours, which were orange, blue, red and green for humans. Chromatic contrast was more relevant to newly hatched chicks than to 9-day-old birds, but in neither case could contrast alone account for preferences; especially for orange over blue. For older chicks, there is evidence for categorization of complementary colours, with a boundary at grey.

Enhanced learning of natural visual sequences in newborn chicks.

PubMed

Wood, Justin N; Prasad, Aditya; Goldman, Jason G; Wood, Samantha M W

2016-07-01

To what extent are newborn brains designed to operate over natural visual input? To address this question, we used a high-throughput controlled-rearing method to examine whether newborn chicks (Gallus gallus) show enhanced learning of natural visual sequences at the onset of vision. We took the same set of images and grouped them into either natural sequences (i.e., sequences showing different viewpoints of the same real-world object) or unnatural sequences (i.e., sequences showing different images of different real-world objects). When raised in virtual worlds containing natural sequences, newborn chicks developed the ability to recognize familiar images of objects. Conversely, when raised in virtual worlds containing unnatural sequences, newborn chicks' object recognition abilities were severely impaired. In fact, the majority of the chicks raised with the unnatural sequences failed to recognize familiar images of objects despite acquiring over 100 h of visual experience with those images. Thus, newborn chicks show enhanced learning of natural visual sequences at the onset of vision. These results indicate that newborn brains are designed to operate over natural visual input.

Chondroitin sulfate effects on neural stem cell differentiation.

PubMed

Canning, David R; Brelsford, Natalie R; Lovett, Neil W

2016-01-01

We have investigated the role chondroitin sulfate has on cell interactions during neural plate formation in the early chick embryo. Using tissue culture isolates from the prospective neural plate, we have measured neural gene expression profiles associated with neural stem cell differentiation. Removal of chondroitin sulfate from stage 4 neural plate tissue leads to altered associations of N-cadherin-positive neural progenitors and causes changes in the normal sequence of neural marker gene expression. Absence of chondroitin sulfate in the neural plate leads to reduced Sox2 expression and is accompanied by an increase in the expression of anterior markers of neural regionalization. Results obtained in this study suggest that the presence of chondroitin sulfate in the anterior chick embryo is instrumental in maintaining cells in the neural precursor state.

Gene Expression in Pre-MBT Embryos and Activation of Maternally-Inherited Program of Apoptosis to be Executed at around MBT as a Fail-Safe Mechanism in Xenopus Early Embryogenesis

PubMed Central

Shiokawa, Koichiro; Aso, Mai; Kondo, Takeshi; Uchiyama, Hiroaki; Kuroyanagi, Shinsaku; Takai, Jun-Ichi; Takahashi, Senji; Kajitani, Masayuki; Kaito, Chikara; Sekimizu, Kazuhisa; Takayama, Eiji; Igarashi, Kazuei; Hara, Hiroshi

2008-01-01

S-adenosylmethionine decarboxylase (SAMDC) is an enzyme which converts S-adenosylmethione (SAM), a methyl donor, to decarboxylated SAM (dcSAM), an aminopropyl donor for polyamine biosynthesis. In our studies on gene expression control in Xenopus early embryogenesis, we cloned the mRNA for Xenopus SAMDC, and overexpressed the enzyme by microinjecting its mRNA into Xenopus fertilized eggs. In the mRNA-injected embryos, the level of SAMDC was enormously increased, the SAM was exhausted, and protein synthesis was greatly inhibited, but cellular polyamine content did not change appreciably. SAMDC-overexpressed embryos cleaved and developed normally up to the early blastula stage, but at the midblastula stage, or the stage of midblastula transition (MBT), all the embryos were dissociated into cells, and destroyed due to execution of apoptosis. During cleavage SAMDC-overexpressed embryos transcribed caspase-8 gene, and this was followed by activation of caspase-9. When we overexpressed p53 mRNA in fertilized eggs, similar apoptosis took place at MBT, but in this case, transcription of caspase-8 did not occur, however activation of caspase-9 took place. Apoptosis induced by SAMDC-overexpression was completely suppressed by Bcl-2, whereas apoptosis induced by p53 overexpression or treatments with other toxic agents was only partially rescued. When we injected SAMDC mRNA into only one blastomere of 8- to 32-celled embryos, descendant cells of the mRNA-injected blastomere were segregated into the blastocoel and underwent apoptosis within the blastocoel, although such embryos continued to develop and became tadpoles with various extents of anomaly, reflecting the developmental fate of the eliminated cells. Thus, embryonic cells appear to check themselves at MBT and if physiologically severely-damaged cells occur, they are eliminated from the embryo by activation and execution of the maternally-inherited program of apoptosis. We assume that the apoptosis executed at MBT is a �

Face recognition in newly hatched chicks at the onset of vision.

PubMed

Wood, Samantha M W; Wood, Justin N

2015-04-01

How does face recognition emerge in the newborn brain? To address this question, we used an automated controlled-rearing method with a newborn animal model: the domestic chick (Gallus gallus). This automated method allowed us to examine chicks' face recognition abilities at the onset of both face experience and object experience. In the first week of life, newly hatched chicks were raised in controlled-rearing chambers that contained no objects other than a single virtual human face. In the second week of life, we used an automated forced-choice testing procedure to examine whether chicks could distinguish that familiar face from a variety of unfamiliar faces. Chicks successfully distinguished the familiar face from most of the unfamiliar faces-for example, chicks were sensitive to changes in the face's age, gender, and orientation (upright vs. inverted). Thus, chicks can build an accurate representation of the first face they see in their life. These results show that the initial state of face recognition is surprisingly powerful: Newborn visual systems can begin encoding and recognizing faces at the onset of vision. (c) 2015 APA, all rights reserved).

Effects of in ovo feeding of creatine pyruvate on the hatchability, growth performance and energy status in embryos and broiler chickens.

PubMed

Zhao, M M; Gao, T; Zhang, L; Li, J L; Lv, P A; Yu, L L; Gao, F; Zhou, G H

2017-10-01

The effects of in ovo feeding (IOF) of creatine pyruvate (CrPyr) on the hatchability, growth performance and energy status of embryos and broilers (Arbor Acres) were investigated. Five treatments were arranged as non-injected treatment (Control), 0.6 ml physiological saline (0.75%) injected treatment (Saline), and IOF treatments injected with 0.6 ml physiological saline (0.75%) containing 3, 6 or 12 mg CrPyr (CrPyr3, CrPyr6 or CrPyr12) into the amnion per fertile egg on day 17.5 of incubation. After hatching, 80 male chicks from each treatment with similar weight close to the average BW of their pooled group were selected and randomly assigned into eight replicates of 10 chicks each. The results showed that the hatchability was not affected among groups, whereas the hatching weight of broilers in CrPyr12 was significantly higher than the control and saline groups (P0.05). Irrespective of dosage, the concentrations of creatine and phosphocreatine, and activities of creatine kinase in embryos were enhanced in CrPyr treatments at 19 E when compared with the control and saline groups (P<0.05). The activities of glucose-6-phosphatase in liver in CrPyr6 and CrPyr12 treatments were higher than the control and saline groups at 19 E (P<0.05). In conclusion, these results indicated that IOF of CrPyr, especially at the level of 12 mg/egg, could improve energy status of embryos and hatchlings, which was useful for enhancing hatching weight, BW and pectoral muscle weight until the end of the experiments at 21 days post-hatch in broilers.

Metabolic fate of yolk fatty acids in the developing king penguin embryo.

PubMed

Groscolas, René; Fréchard, Françoise; Decrock, Frédéric; Speake, Brian K

2003-10-01

This study examines the metabolic fate of total and individual yolk fatty acids (FA) during the embryonic development of the king penguin, a seabird characterized by prolonged incubation (53 days) and hatching (3 days) periods, and a high n-3/n-6 polyunsaturated FA ratio in the egg. Of the approximately 15 g of total FA initially present in the egg lipid, 87% was transferred to the embryo by the time of hatching, the remaining 13% being present in the internalized yolk sac of the chick. During the whole incubation, 83% of the transferred FA was oxidized for energy, with only 17% incorporated into embryo lipids. Prehatching (days 0-49), the fat stores (triacylglycerol) accounted for 58% of the total FA incorporated into embryo lipid. During hatching (days 49-53), 40% of the FA of the fat stores was mobilized, the mobilization of individual FA being nonselective. At hatch, 53% of the arachidonic acid (20:4n-6) of the initial yolk had been incorporated into embryo lipid compared with only 15% of the total FA and 17-24% of the various n-3 polyunsaturated FA. Similarly, only 32% of the yolk's initial content of 20:4n-6 was oxidized for energy during development compared with 72% of the total FA and 58-66% of the n-3 polyunsaturated FA. The high partitioning of yolk FA toward oxidization and the intense mobilization of fat store FA during hatching most likely reflect the high energy cost of the long incubation and hatching periods of the king penguin. The preferential partitioning of 20:4n-6 into the structural lipid of the embryo in the face of its low content in the yolk may reflect the important roles of this FA in tissue function.

Cooling strategies for brazilian flounder Paralichthys orbignyanus embryos.

PubMed

Varela, A S; Cardoso, T F; Fernandes E Silva, E; Goularte, K L; Okamoto, M H; Sampaio, L A; Jardim, R D; Corcini, C D

Paralichthys orbignyanus is the species of the greatest potential for marine and estuarine fish farming in southern Brazil. Consequently, embryo cryopreservation becomes an important tool for increasing their production. To evaluate the effects of cooling protocols on the viability of embryos of P. orbignyanus at two stages of development (neurula and early differentiation of the tail). Control embryos were maintained at 23 degree C and treated embryos were cooled to 15 degree C, 10 degree C and 5 degree C at rapid, moderate and slow cooling rates. Then embryos were maintained at these different temperatures for 30, 60 and 90 min and the loss of viability assessed as hatching rates (HR) and morphologically normal larvae (MNL). The average HR for embryos following cooling was higher for those at the tail stage compared to the neurula stage (P<0.05). In both stages there was no statistical difference between the HR of control embryos and those exposed to rapid cooling. Also for tail stage embryos, there was no difference between MNL of control and rapidly cooled embryos. As first steps in the development of cryopreservation methods for P. orbignyanus embryos, the use of a rapid cooling and holding at 5 degree C for 30 min are recommended.

Reduced heart rate and cardiac output differentially affect angiogenesis, growth, and development in early chicken embryos (Gallus domesticus).

PubMed

Branum, Sylvia R; Yamada-Fisher, Miho; Burggren, Warren

2013-01-01

An increase in both vascular circumferential tension and shear stress in the developing vasculature of the chicken embryo has been hypothesized to stimulate angiogenesis in the developing peripheral circulation chorioallantoic membrane (CAM). To test this hypothesis, angiogenesis in the CAM, development, and growth were measured in the early chicken embryo, following acute and chronic topical application of the purely bradycardic drug ZD7288. At hour 56, ZD7288 reduced heart rate (f(H)) by ~30% but had no significant effect on stroke volume (~0.19 ± 0.2 μL), collectively resulting in a significant fall in cardiac output (CO) from ~27 ± 3 to 18 ± 2 μL min(-1). Mean f(H) at 72 h of development was similarly significantly lowered by acute ZD7288 treatment (250 μM) to 128 ± 0.3 beats min(-1), compared with 174.5 ± 0.3 and 174.7 ± 0.8 beats min(-1) in control and Pannett-Compton (P-C) saline-treated embryos, respectively. Chronic dosing with ZD7288-and the attendant decreases in f(H) and CO-did not change eye diameter or cervical flexion (key indicators of development rate) at 120 h but significantly reduced overall growth (wet and dry body mass decreased by 20%). CAM vessel density index (reflecting angiogenesis) measured 200-400 μm from the umbilical stalk was not altered, but ZD7288 reduced vessel numbers-and therefore vessel density-by 13%-16% more distally (500-600 μm from umbilical stalk) in the CAM. In the ZD7288-treated embryos, a decrease in vessel length was found within the second branch order (~300-400 μm from the umbilical stock), while a decrease in vessel diameter was found closer to the umbilical stock, beginning in the first branch order (~200-300 μm). Paradoxically, chronic application of P-C saline also reduced peripheral CAM vessel density index at 500 and 600 μm by 13% and 7%, respectively, likely from washout of local angiogenic factors. In summary, decreased f(H) with reduced CO did not slow development rate but reduced embryonic

The effect of para-chlorophenylalanine and scopolamine on passive avoidance in chicks.

PubMed

Mattingly, B A; Zolman, J F

1981-05-01

Four-day-old Vantress x Arbor Acre chicks were treated for key-peck passive avoidance (PA) learning following intraperitoneal injections of parachlorophenylalanine (PCPA) and/or scopolamine. In Experiment 1, chicks were pre-treated with either three or five injections of PCPA (150 mg/kg) or saline across th first three posthatch days and then tested for PA learning on the fourth posthatch day. In Experiment 2, chicks were first pre-treated with three injections of PCPA (150 mg/kg) or saline, and then injected with either scopolamine (0.5 mg/kg) or saline 20 min prior to PA testing on the fourth posthatch day. Major findings were: (a) Chicks pre-treated with PCPA did not significantly differ from saline control chicks in either the acquisition or maintenance of response suppression during PA testing; (b) chicks injected with scopolamine were significantly disrupted in PA learning as compared to saline control chicks; and (c) PCPA pre-treatment did not significantly affect the scopolamine-induced disruption of PA learning. These findings, therefore, suggest that cholinergic, but not serotonergic, mechanisms are involved in PA learning of the young chick.

Mechanisms of Microwave Induced Damage in Biologic Materials

DTIC Science & Technology

1992-10-01

that low level electromagnetic fields can cause developmental abnormalities in early stages of chick embryo development . In studies of the effects of...early embryonic development has led to a great deal of speculation about the safety of environmental exposure to such fields. Power lines, household...capable of covalent binding to embryonic or fetal macromolecules and nucleic acids, disrupting normal development . Individuals with low levels of

Mitochondrial DNA content in embryo culture medium is significantly associated with human embryo fragmentation.

PubMed

Stigliani, S; Anserini, P; Venturini, P L; Scaruffi, P

2013-10-01

approach we are proposing may provide a novel, non-invasive, objective tool for embryo quality grading. The correlation between a high mtDNA concentration and the fragmentation rate of embryos is suggestive that fragments are mainly anuclear cytoplasmatic debris arising during cleavage. Therefore, blastomere shaping as an early event during in vitro development may play a homeostatic role and be related to embryo competence. This project was funded by Merck Serono (Grant for Fertility Innovation 2011). The sponsor had no role in study design, data collection, data analysis, data interpretation and writing of the paper. Authors declare no conflicts of interest. ClinicalTrials.gov Identifier: NCT01397136.

Mechanical Influences on Morphogenesis of the Knee Joint Revealed through Morphological, Molecular and Computational Analysis of Immobilised Embryos

PubMed Central

Roddy, Karen A.; Prendergast, Patrick J.; Murphy, Paula

2011-01-01

Very little is known about the regulation of morphogenesis in synovial joints. Mechanical forces generated from muscle contractions are required for normal development of several aspects of normal skeletogenesis. Here we show that biophysical stimuli generated by muscle contractions impact multiple events during chick knee joint morphogenesis influencing differential growth of the skeletal rudiment epiphyses and patterning of the emerging tissues in the joint interzone. Immobilisation of chick embryos was achieved through treatment with the neuromuscular blocking agent Decamethonium Bromide. The effects on development of the knee joint were examined using a combination of computational modelling to predict alterations in biophysical stimuli, detailed morphometric analysis of 3D digital representations, cell proliferation assays and in situ hybridisation to examine the expression of a selected panel of genes known to regulate joint development. This work revealed the precise changes to shape, particularly in the distal femur, that occur in an altered mechanical environment, corresponding to predicted changes in the spatial and dynamic patterns of mechanical stimuli and region specific changes in cell proliferation rates. In addition, we show altered patterning of the emerging tissues of the joint interzone with the loss of clearly defined and organised cell territories revealed by loss of characteristic interzone gene expression and abnormal expression of cartilage markers. This work shows that local dynamic patterns of biophysical stimuli generated from muscle contractions in the embryo act as a source of positional information guiding patterning and morphogenesis of the developing knee joint. PMID:21386908