Academic literature on the topic 'Chickens Embryos Growth'
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Journal articles on the topic "Chickens Embryos Growth"
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Chelnokova, Marina I., and Andrey A. Chelnokov. "Features of development of visceral organs in embryos of egg cross chickens ‘Lohmann Brown’ under red and green monochromatic LED lighting." RUDN Journal of Agronomy and Animal Industries 17, no. 1 (April 2, 2022): 112–23. http://dx.doi.org/10.22363/2312-797x-2022-17-1-112-123.
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New data on the features of development of visceral organs in embryos of egg cross chickens Lohmann Brown under red and green monochromatic LED lighting were obtained. The effect of two continuous LED lighting modes has been studied: experimental modes - r ed and green light, control - d arkness. The absolute values of weight dimensions and specific growth rate (according to the Schmalhausen-Brody formula) of heart, muscular stomach, liver of chicken embryos were estimated using morphometric methods. The studies proved that red and green LED lighting has a stimulating effect on the embryonic development of visceral organs (heart, muscular stomach, liver) in Lohmann Brown egg cross compared to the control (darkness). Under red and green LED stimulation, chicken embryos prevailed in the heart mass from the 14th to the 20th day of embryogenesis. The muscular stomach and liver of chicken embryos developed more intensively under red illumination on the 18th and 20th days, and under green illumination - a similar effect on the muscular stomach was noted on the 19th and 20th days, on the liver - o n the 20th day. It has been established that in the early ontogenesis of Lohmann Brown chickens there were several critical stages (phases). They fall on different days of development and characterize the features of rhythmicity in growth processes of visceral organs in chicken embryogenesis under LED stimulation of red and green spectrum. Chicken embryos under red and green illumination had the highest growth rate of heart on the 17th and 20th day, respectively; muscular stomach under red illumination - o n the 17th and 20th days, liver - on the 16th and 17th day under red and green illumination. By the hatching period on the 20th day, there were no differences in the development of visceral organs of chicken embryos depending on red and green light spectrum. The hatching of Lohmann Brown chicken embryos exposed to red and green light occurred on the 20th day of incubation - a day earlier than under control conditions (darkness). The proposed biological causes underlying the effect of monochromatic light of different color spectrum on embryogenesis of chicken embryo and organs are discussed.
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Mafruchati, Maslichah, Akhmad Kusuma Wardhana, and Wan Iryani Wan Ismail. "Disease and viruses as negative factor prohibiting the growth of broiler chicken embryo as research topic trend: a bibliometric review." F1000Research 11 (September 29, 2022): 1124. http://dx.doi.org/10.12688/f1000research.125016.1.
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Background Broiler chickens have properties as meat-producing poultry and produce meat with soft fiber quality. Broiler’s embryo needs to be given attention, especially against disease. The purpose of the study was to observe the trend of the research topic and external factors which could affect the embryo’s growth of broiler. Methods This study used meta-data from Scopus. There were 162 samples started from 2006-to 2022. The data were analyzed using a bibliometric method with two software, Vosviewer, and Biblioshiy from R studio. Results It was found that the study of broiler chicken embryos had developed well, especially those related to genetics, disease, and also the immunity system. But the result showed that topics about the disease, viruses, and bacteria were more popular than topics about the gene. The result also showed that based on the importance and development of topics, the words such as “chicken”, “genes”, “development”, “effect”, growth”, and “control” had importance for the study and developed well in research. It means that genes influenced the growth of the embryo of a chicken. But still, even though a chicken gene was predetermined, the genetic engineering of chicken insemination to produce a superior breed with a fast-growing rate of the embryo could be used. Conclusions It could be stated that disease, especially research about the virus is one of the main determinants that could affect the growth of the embryo of broiler chicken.
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Ding, Peng, Yueyue Tong, Shu Wu, Xin Yin, Huichao Liu, Xi He, Zehe Song, and Haihan Zhang. "The Sexual Effect of Chicken Embryos on the Yolk Metabolites and Liver Lipid Metabolism." Animals 12, no. 1 (December 29, 2021): 71. http://dx.doi.org/10.3390/ani12010071.
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The metabolic processes of animals are usually affected by sex. Egg yolk is the major nutrient utilized for the growth and development of a chicken embryo. In this study, we explored the differences of yolk metabolites in male and female chicken embryos by LC–MS/MS. Furthermore, we investigated the mRNA expression of lipoprotein lipase (LPL) and fatty acid synthase (FAS) in chicken embryo liver with different sexes in different embryonic stages. The results showed that the nutrient metabolites in the yolk of female chickens were mainly related to lipid metabolism and amino acid metabolism in the early embryonic stage, and vitamin metabolism in the late embryonic stage. The male yolk metabolites were mainly associated with lipid metabolism and nucleic acid metabolism in the early developmental stage, and amino acids metabolism in the late embryonic stage. There was no significant difference in the expression of LPL or FAS in livers of male and female chicken embryos at different embryonic stages. Our results may lead to a better understanding of the sexual effect on yolk nutrient metabolism during chicken embryonic development.
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Hoshino, S., M. Wakita, Y. Kobayashi, T. Kakegawa, and M. Suzuki. "Effects of thyroid hormones on cartilage sulphation in sex-linked dwarf chickens." Acta Endocrinologica 121, no. 1 (July 1989): 107–11. http://dx.doi.org/10.1530/acta.0.1210107.
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Abstract. The present investigation was undertaken to see if exogenous thyroid hormone could stimulate cartilage sulphation in vivo and in vitro in sex-linked dwarf chickens. L-thyroxine or L-3,5,3'-triiodothyronine injection for 7 consecutive days stimulated in vivo 35SO2−4 incorporation into trachea cartilages of the dwarf chicken. Both thyroid hormones added to the incubation medium with or without 2.5% dwarf chicken serum also stimulated in vitro 35SO2−4 incorporation into pelvic rudiment from 11-day chick embryos. These data demonstrate that thyroid hormones, like insulin-like growth factor I, might be responsible for the reduced growth rate of dwarf chickens.
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Bhanja, S. K., M. Sudhagar, A. Goel, N. Pandey, M. Mehra, S. K. Agarwal, and A. Mandal. "Differential expression of growth and immunity related genes influenced by in ovo supplementation of amino acids in broiler chickens." Czech Journal of Animal Science 59, No. 9 (October 1, 2014): 399–408. http://dx.doi.org/10.17221/7651-cjas.
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The present study was aimed at investigating the role of in ovo administered amino acids: lysine, arginine, threonine or methionine plus cysteine (Met+Cys) in 14-day embryos on expression profile of growth (chicken growth hormone (cGH), insulin like growth factors (IGF) I and II, and mucin) and immunity related genes (IL-2, IL-4, IL-6, IL-12, TNF-α, and IFN-γ). On incubation day (ID) 18, higher (P < 0.01) cGH and mucin gene expression was observed in lysine, threonine, arginine or Met+Cys injected embryos, while IGF-II expression was higher in threonine, arginine or Met+Cys injected embryos on ID 20. Expression of growth genes was down regulated (P < 0.01) on day of hatch in most of the amino acids injected chicks. On day 7 post-hatch (PH), threonine or arginine exhibited higher expression of cGH, IGF-I, and IGF-II but higher mucin gene expression only on day 14 PH. Threonine or Met+Cys injected birds had higher expression of IL-6 and TNF-α, while arginine injected birds had higher TNF-α expression. Lysine, threonine or Met+Cys injected birds had higher IL-2, but lower of IL-12 and IFN-γ gene expression. It is concluded that arginine and threonine enhanced the expression of growth related genes, while threonine and Met+Cys modulated expression of immune genes in broiler chickens.
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CHELNOKOVA, M. I., А. А. CHELNOKOV, and YU V. ARZHANKOVA. "THE IMPACT OF VARIABLE INCUBATION TEMPERATURE ON THE GROWTH AND METABOLISM OF EGG CROSS CHICKEN EMBRYOS AND THE DEVELOPMENT OF THEIR VISCERAL ORGANS." Izvestiâ Timirâzevskoj selʹskohozâjstvennoj akademii, no. 6 (2021): 112–28. http://dx.doi.org/10.26897/0021-342x-2021-6-112-128.
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The article discusses issues related to the impact of variable incubation temperature (37.8°C – from the 1st to the 14th day; 39.5°C, two hours daily, in the 15th-17th days; 37.5°C – 18th day; 37.0°C – 19th-21st day; relative humidity is 57.0%) on the growth and metabolic rates of the Hysex Brown and Lohmann Brown crosses chicken embryos as well as on the development of their visceral organs and the incubation effectiveness itself. Currently, most of the research is devoted to studying the influence of variable egg incubation temperatures while using one cross of chickens and comparison with the standard incubation mode. A necessary condition for the balanced development of productive bird embryos is the acquisition of knowledge about their morphophysiological parameters and metabolic needs, based on which it is possible to adjust regimes of artificial egg incubation. The research results have shown that the developed and tested incubation regime with variable temperatures is most effective for hen eggs of the Lohmann Brown cross compared to the Hysex Brown cross. This positive effect was expressed in a more intensive growth of chicken embryos and the development of some visceral organs (gizzard stomach, spleen), as well as in the most pronounced rate of gas exchange (CO2), the highest energy value of embryos and the lowest total energy consumption for growth and metabolism in the period from 4 days of incubation to the hatching time. Differentiation of the temperature regime during embryogenesis has a positive effect on incubation results. The percentage of withdrawal of the Lohmann Brown cross young chickens is 4% higher than that of the Hysex Brown cross due to decreased embryonic mortality and decreased number of frozen embryos and suffocated chickens. This kind of research, in our opinion, is an auspicious one, and it is necessary to adjust the existing incubation regimes of hen eggs in various production areas.
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Stanishevskaya, Olga I., and Elena S. Fedorova. "Dosed Exposure to Low Temperature as a Breeding Background in The Selection of Gene Pool Breeds of Chickens for Viral Vaccines Production." Open Agriculture Journal 14, no. 1 (December 31, 2020): 345–51. http://dx.doi.org/10.2174/1874331502014010345.
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Background: One of the ways to utilize the potential of local breeds is to use them as producers of raw materials for the bio-industry (production of vaccines and diagnostics for animals and humans). Methods: Breeding of Russian White (PRWC) laying hens in 5 generations was carried out with the aim of increasing the output of allantois-amniotic fluid of embryos with a selective background (cooling of hatching eggs during the sensitive period of embryogenesis). In F5, the thermoregulation capabilities of 7-day-old PRWC chickens were studied in comparison with Amrox chickens under the influence of a daily stress factor (cooling at +10oC for 30 minutes) and raising at +22oC. The level of allantois-amniotic fluid output and biological activity of the Newcastle disease virus in F5 PRWC embryos in comparison with F0 and commercial line embryos was evaluated. Results: Day-old PRWC chicks responded to exposure to low sublethal temperature with muscle shivering, but, unlike Amrox chickens, they were active and retained the reflex of searching for food. PRWC chickens raised at low temperatures up to 7 days of age maintained the same growth rate as chickens raised at a common regime but used less residual yolk, which practically did not decrease the body temperature, and change the level of thyrotrophic hormone in response to the dosed exposure at low temperatures at 7 days of age. The content of doses of the Newcastle disease virus (EID50) in the extraembryonic fluid of F5-embryos of PRWC was 32.3 times higher than that of commercial line ones. Conclusion: PRWC chicks in the early neonatal period are more reactive at low temperature and have better thermoregulation mechanisms. PRWC embryos can be recommended for use in the production of various viral vaccines as well as diagnosticums.
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Lambeth, Luke S., Kirsten R. Morris, Terry G. Wise, David M. Cummins, Terri E. O'Neil, Yu Cao, Andrew H. Sinclair, Timothy J. Doran, and Craig A. Smith. "Transgenic Chickens Overexpressing Aromatase Have High Estrogen Levels but Maintain a Predominantly Male Phenotype." Endocrinology 157, no. 1 (January 1, 2016): 83–90. http://dx.doi.org/10.1210/en.2015-1697.
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Abstract Estrogens play a key role in sexual differentiation of both the gonads and external traits in birds. The production of estrogen occurs via a well-characterized steroidogenic pathway, which is a multistep process involving several enzymes, including cytochrome P450 aromatase. In chicken embryos, the aromatase gene (CYP19A1) is expressed female-specifically from the time of gonadal sex differentiation. Ectopic overexpression of aromatase in male chicken embryos induces gonadal sex reversal, and male embryos treated with estradiol become feminized; however, this is not permanent. To test whether a continuous supply of estrogen in adult chickens could induce stable male to female sex reversal, 2 transgenic male chickens overexpressing aromatase were generated using the Tol2/transposase system. These birds had robust ectopic aromatase expression, which resulted in the production of high serum levels of estradiol. Transgenic males had female-like wattle and comb growth and feathering, but they retained male weights, displayed leg spurs, and developed testes. Despite the small sample size, this data strongly suggests that high levels of circulating estrogen are insufficient to maintain a female gonadal phenotype in adult birds. Previous observations of gynandromorph birds and embryos with mixed sex chimeric gonads have highlighted the role of cell autonomous sex identity in chickens. This might imply that in the study described here, direct genetic effects of the male chromosomes largely prevailed over the hormonal profile of the aromatase transgenic birds. This data therefore support the emerging view of at least partial cell autonomous sex development in birds. However, a larger study will confirm this intriguing observation.
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Özlü, Serdar. "Comparative Staging of Blastoderm Development at Oviposition in Eggs from Layer and Broiler Grandparent Breeder Flocks." Turkish Journal of Agriculture - Food Science and Technology 9, no. 6 (July 8, 2021): 1232–36. http://dx.doi.org/10.24925/turjaf.v9i6.1232-1236.4348.
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Recent decades were characterized by genetic selection of broiler and layer chickens for enhanced growth rate and meat yield or intensified egg production, respectively. It is to be expected that genetic selection for various traits would also influence embryo development. The effects of different strains of chickens on egg weight, stage of blastoderm, variation of the blastoderm development and Pearson correlation between egg weight and stage of blastoderm at oviposition were studied in the current study. Hatching eggs were randomly collected from three layer chicken lines (Layer-1, Layer-2, and Layer-3) raised in Poultry Research Institute, and two broiler grandparent flocks (Female and Male) from Aviagen Anadolu. The age of all chicken lines was 36 week. A total of 30 eggs in each line were used, and egg weight and the blastoderm development of the embryos were determined at oviposition time. At the end of the research, significant difference in egg weights (P0.05). The mean stage of blastoderm development in male grandparent line eggs significantly lower than other four genetic lines (P
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Mazumder, AC, S. Khatun, M. Nooruzzaman, EH Chowdhury, PM Das, and MR Islam. "Isolation and identification of Newcastle disease viruses from field outbreaks in chickens and pigeons." Bangladesh Veterinarian 29, no. 2 (March 30, 2013): 41–48. http://dx.doi.org/10.3329/bvet.v29i2.14341.
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Eleven dead or sick birds submitted from farms in the year 2010 with a history of sudden death with respiratory and/or diarrhoeal signs were used for isolation and identification of Newcastle disease virus (NDV). All samples were subjected to routine necropsy. Pooled respiratory tissues were inoculated in embryonated chicken eggs and chicken embryo fibroblast (CEF) cell culture. The growth of NDV was confirmed by embryo mortality, cytopathic effects (CPE) in cell culture, haemagglutination (HA) and haemagglutination inhibition (HI) test. The presence of NDV was confirmed by reverse transcriptionpolymerase chain reaction (RT-PCR). At necropsy seven cases were tentatively diagnosed as Newcastle disease (ND). Out of seven ND-suspected samples, four yielded virus in both embryos and cell culture, while one was positive only in embryos, one only in cell culture and one sample was negative in both embryos and cell culture. RT-PCR successfully amplified a 766 bp fragment covering parts of Matrix and Fusion protein genes of NDV from the samples that were positive either in embryos or in cell culture. It is suggested that RT-PCR could be a rapid and sensitive tool for the detection of NDV. DOI: http://dx.doi.org/10.3329/bvet.v29i2.14341 Bangl. vet. 2012. Vol. 29, No. 2, 41-48
Dissertations / Theses on the topic "Chickens Embryos Growth"
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Ruck, Sylvia A. "Induced Bradycardia Effects on Angiogenesis, Growth and Development in Early Development in Chicken Embryos, Gallus Domesticus." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33199/.
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Cardiac performance, angiogenesis and growth was investigated during early chicken development. Heart rate, and thus arterial pulse pressure and cardiac output, were altered with the bradycardic drug ZD7288. Heart rates at 72 h of development of control embryos and those dosed with chicken Ringer were not different at 171 bpm. Acute and chronic application of ZD7288 caused significant bradycardia. Chronic dosing of Ringer and ZD7288 changed neither eye diameter nor development rate. Chronic dosing of ZD7288 did not significantly alter CAM vessel density close to the embryo (2, 3 and 4 mm) but at farther distances (5 and 6 mm) chronic dosing with both Ringer and ZD7288 decreased vessel density by 13 - 16%. Chronic dosing with ZD7288 also reduced body mass by 20%. Thus, lowered heart rate and cardiac output had little effect on vessel density or developmental stage, but did reduce embryo growth.
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Antczak, Michael Richard. "Growth factor- and oncogene-induced transformation in chicken embryo fibroblasts and normal diploid human fibroblasts." Case Western Reserve University School of Graduate Studies / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=case1057173851.
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Bomotti, Samantha Marie. "The Fibrolast Growth Factor Pathway: A Necessary and Sufficient Means of Inducing Endothelial Cell Development in Nascent Chicken Embryos." Thesis, The University of Arizona, 2011. http://hdl.handle.net/10150/144237.
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AFZAL, RAHMAN. "Noninvasive Preincubation Sex Determination and Monitoring of Sex-Specific Early Embryonic Growth Rate in Chicken Eggs Using Longitudinal Visible Transmission Spectroscopy." Kyoto University, 2020. http://hdl.handle.net/2433/259049.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第22781号
農博第2424号
新制||農||1081(附属図書館)
学位論文||R2||N5301(農学部図書室)
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 近藤 直, 准教授 小川 雄一, 教授 飯田 訓久
学位規則第4条第1項該当
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KHALIDUZZAMAN. "Non-destructive Classification of Chick Embryos Based on Heartbeat, Body Motility and Growth Using Signal Processing of Near-infrared Light." Kyoto University, 2019. http://hdl.handle.net/2433/244555.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第22074号
農博第2366号
新制||農||1072(附属図書館)
学位論文||R1||N5228(農学部図書室)
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 近藤 直, 准教授 小川 雄一, 教授 飯田 訓久
学位規則第4条第1項該当
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Kamaid, Toth Andres. "BMP4 regulation of sensory organ development in the chick inner ear." Doctoral thesis, Universitat Pompeu Fabra, 2008. http://hdl.handle.net/10803/7137.
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Bone morphogenetic proteins (BMPs) are diffusible molecules involved in a variety of cellular interactions during development. In particular, Bmp4 expression accompanies the development of the ear sensory organs during patterning and specification of sensory cell fates, and it has been shown to play a role in inner ear development and morphogenesis. However, there is no understanding of the cellular effects of BMP4 in prosensory progenitors, and about its role in the process of sensory fate specification. The present thesis project was aimed at exploring the effects of BMP-signaling on the development of hair-cells, using the chick inner ear as a model.The specific aims proposed were:
1- Analyze the cellular effects caused by addition of BMP4 in a model of isolated chick otic vesicles in culture, measuring parameters of cell proliferation, cell death and sensory cell fate specification.
2- Analyze the cellular effects caused by inhibition of BMP4 signaling in a model of isolated chick otic vesicles in culture, measuring parameters of cell proliferation, cell death and sensory cell fate specification.
3- Analyze the expression in the innear ear of downstream targets of BMP signalling, in particular, analyse the members of Id gene family.
4- Analyze the regulation of Id genes by BMP signalling in the inner ear.
5- Analyze the expression of genes involved in the process of terminal differentiation, in particular, Btg1 and Btg2 genes
6- Analyze the regulation of Btg1 and Btg2 gene by BMP signalling in the inner ear
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Verna, Jean-Marc. "Analyse "in vitro" de l'innervation sélective du derme et de l'épiderme chez l'embryon de poulet : rôle de divers facteurs d'origine matricielle et cellulaire." Grenoble 1, 1987. http://www.theses.fr/1987GRE10023.
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Wang, Hsiao-Tien, and 王效天. "Effects of Surgical Caponization and Administration of Estradiol to Chicken Embryos on Daily Activity, Agonistic Behavior, Growth Performance, Carcass Traits and Sensory Evaluation of Males Taiwan Country Chickens." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/68806831614781378710.
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碩士國立中興大學
畜產學系
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Effects of Surgical Caponization and Administration of Estradiol to Chicken Embryos on Daily Activity, Agonistic Behavior, Growth Performance, Carcass Traits and Sensory Evaluation of Males Taiwan Country Chickens Summary The Taiwan Country Chicken B×L2 strain, established at the National Chung-Hsing University, were used to study the effects of surgical caponization and administration of estradiol to embryo on the behavioral, growth and carcass traits of male chickens. The three experimental groups were, the capon group, surgically caponized at 8 weeks of age, the E2 group, administrated with estradiol before incubation, and the intact control group. The chicken’s growth and behavioral traits were measured from 11 to 33 weeks of age, and the shear value and sensory evaluation scores of breast and leg meats were tested at 14 and 33 weeks of age. Experimental results are as follows: For feeding time, the E2 group (19.79%) was significantly higher than the control (16.76%) and the capon group (11.45%). For grooming time, the capon group (22.31%) was significantly higher than the E2 (15.25%) and the control groups (11.94%). For crouching time, the capon group (17.10%) was significantly higher than the E2 (13.15%) and the control group (9.56%). For standing and walking time, the capon group (45.69%) and the E2 group (48.21%) were significantly higher than the control group (58.32%). Agonistic behaviors were observed at 12~16, 19~23, and 31~35 weeks of age periods. Totally, every pen was observed for 18 hours. It was found that the total frequency of fighting in the E2 (48 times) and the capon group (65 times) were significantly lower than that of the control (296 times). Means of aggressive acts (acts/hour/bird) of the capon (0.956) and the E2 group (2.233) were significantly lower than that of the control (3.246). For the growth performance, the feed conversion ratio of the E2 group and the capon group were significantly better than the control from 10 to 16 weeks of age, and so was the body weight after 20 weeks of age. The comb size of the capon group was always significantly smaller than that of the E2 and the control group. At 14 and 16 weeks of age, the capon group had the worst feather score, the control had the next and the E2 had the best score. At 24 and 32 weeks of age, both the E2 and the capon group maintained very good condition of feather covering, and their feather scores were highly significantly better than that of the control. At 14 weeks of age, the leg weight and its ratio to carcass weight of the E2 and the capon group were significantly lower than those of the control. At 34 weeks of age, the breast weight and its ratio to carcass weight of the capon group were significantly higher than those of the E2 and the control group. At 14 weeks of age, the shear value of leg meat of the E2 and the capon group were significantly lower than that of the control. At 33 weeks of age, the shear value of breast meat of the capon was the highest, and that of the E2 was the lowest; for the leg meat, the capon group had the lowest shear value, and the control had the highest value. The sensory evaluation at 14 weeks of age revealed that, for the breast meat, the E2 group had the highest acceptability score, the control had the next and the capon had the lowest; for the leg meat, the E2 group had the highest tenderness score, the capon group had the next and the control had the lowest. The sensory evaluation at 33 weeks of age found no significant difference among groups for any of flavor, tenderness, juiciness and acceptability scores, except for the color scores of breast meat of the capon group were significantly higher than that of the E2 and the control group.
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Miyake, Tetsuaki. "Growth arrested specific gene regulation by C/EBP in chicken embryo fibroblasts /." 2004. http://wwwlib.umi.com/cr/yorku/fullcit?pMQ99360.
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Thesis (M.Sc.)--York University, 2004. Graduate Programme in Biology.Typescript. Includes bibliographical references (leaves 134-161). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ99360
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Maynard, Scott. "The role of C/EBPbeta in proliferation, transformation, and autophagy in chicken embryo fibroblasts /." 2004. http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99209.
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Thesis (Ph.D.)--York University, 2004. Graduate Programme in Biology.Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pNQ99209
Books on the topic "Chickens Embryos Growth"
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Bellairs, Ruth. The atlas of chick development. 2nd ed. Amsterdam: Elsevier, 2005.
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Bellairs, Ruth. The atlas of chick development. San Diego: Academic Press, 1998.
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Bellairs, Ruth. The atlas of chick development. San Diego: Academic Press, 1997.
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Juurlink, B. H. J., 1947-, ed. An atlas for staging mammalian and chick embryos. Boca Raton, Fla: CRC Press, 1987.
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Chelnokova, Marina, Farhat Suleymanov, Andrey Chelnokov, Yuliya Arzhankova, Zoya Nikolaeva, and Ol'ga Lanskaya. Patterns of growth, metabolism of egg cross chicken embryos and the development of their visceral organs under the influence of variable incubation temperatures. ru: INFRA-M Academic Publishing LLC., 2022. http://dx.doi.org/10.12737/1870595.
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The monograph is devoted to the study of the growth patterns, metabolism of chicken egg cross embryos and the development of their visceral organs under the influence of variable incubation temperatures. New data on the main patterns of growth and energy metabolism in the embryogenesis of birds are summarized. Up-to-date information on the growth and development, energy exchange of egg and meat cross chicken embryos is presented. New data have been obtained on the effectiveness of the effect of variable incubation temperature on the growth and metabolism of egg cross chicken embryos and the development of their visceral organs.
It is intended for graduate students and teachers of higher education, researchers related to the problems of artificial incubation of farm birds.
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Legg, Gerald. From Egg to Chicken (Lifecycles). Tandem Library, 2001.
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Scrace, Carolyn. From Egg to Chicken (Lifecycles). 2nd ed. Franklin Watts Ltd, 2005.
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Legg, Gerald. From Egg to Chicken (Lifecycles). Franklin Watts, 1998.
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Legg, Gerald. From Egg to Chicken (Lifecycles). Franklin Watts Ltd, 1997.
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Osmond, Mark, and Ruth Bellairs. Atlas of Chick Development, Second Edition. 2nd ed. Academic Press, 2005.
Find full textBook chapters on the topic "Chickens Embryos Growth"
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Takenaka, Ivone M., Seth Sadis, and Lawrence E. Hightower. "Transforming Growth Factor-ß Regulates Basal Expression of the hsp70 Gene Family in Cultured Chicken Embryo Cells." In Results and Problems in Cell Differentiation, 188–209. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-540-46712-0_13.
Full textConference papers on the topic "Chickens Embryos Growth"
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Turganbaeva, A. S. "Influence of water concentration on the content of protein and nucleic acids in organs of chick embryos of different ages." In VIII Vserossijskaja konferencija s mezhdunarodnym uchastiem «Mediko-fiziologicheskie problemy jekologii cheloveka». Publishing center of Ulyanovsk State University, 2021. http://dx.doi.org/10.34014/mpphe.2021-191-194.
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The study was carried out in 10-, 14-15-, 18-20-day-old embryos and 1-2-day-old chickens of the Hy-Line breed. In chickens during embryogenesis, the peculiarities of the relationship between the main indicator of the ontogenetic growth of organs and tissues - the content of intracellular water by previously measured values: with the concentration of protein and nucleic acids in the organs of chicken embryos of different ages - were assessed.
It was found that in the period of 10-19 days of embryogenesis, the growth of organs is accompanied by a significant decrease in water content to varying degrees: noticeably higher in the liver and in the cerebral hemispheres - up to 14 days; from the 19th day, these changes are less pronounced. The results of the studied indicator in the muscles indicate advanced embryonic development with a more pronounced decrease in the water content in the red oxidative muscles in comparison with white muscles, where the decrease in the indicator is less pronounced.
Key words: chicken embryos, protein, nucleic acid, water content, pectoralis alba and gastrocnemius muscle.
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Ataei, Abdol Hossain, and Figen Kırkpınar. "Application of In-Ovo Injection of Some Substances for Manipulation of Sex and Improving Performance in Chicken." In International Students Science Congress. Izmir International Guest Student Association, 2021. http://dx.doi.org/10.52460/issc.2021.006.
Full textAbstract:
In intensive production, freshly hatched cockerels are culled in the layer hatchery (7 billion males each year), On the other hand, for meat production rearing female birds has not economic benefits because of male broiler chicks have a faster growth rate and better feed efficiency than females. In this regards several methods are being developed for sex determination in the chick embryo during the incubation period. But these methods need to be rapid, cost-efficient, and suitable practical for commercial use. Additionally, sex determination should be done before pain perception has evolved in chick embryos. Biotechnology by in ovo technique to sex determination of between male and female chicks or sex reversal could improve production and eliminate ethical dilemmas for poultry industries. In birds, the differentiation of embryonic gonads is not determined by genetic gender with the certainty that occurs in mammals and can be affected by early treatment with a steroid hormone. During the development of the chick embryo, the genotype of the zygote determines the nature of the gonads, which then caused male or female phenotype. The differentiation of gonads during the period called the "critical period of sexual differentiation" is accompanied by the beginning of secretion of sexual hormones. Namely, any change in the concentration of steroid hormones during the critical period affects the structure of the gonads. Many synthetic anti-aromatases such as federazole and non-synthetic in plants, mushrooms, and fruits containing natural flavonoids have been used in the experiments in ovo injection of anti-aromatase had no negative effect on the growth performance of sexual reversal female chickens. In conclusion, administration of an aromatase inhibitor causes testicular growth in the genetic female gender, and estrogen administration leads to the production of the left ovotestis in the genetic male gender. Therefore, in the early stages of embryonic development, sexual differentiation can be affected by changing the ratio of sexual hormones. In this review, effects of some substances applied by in ovo injection technique on sex reversal and performance in chicks.
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Aygün, Ali, and Doğan Narinç. "The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits." In INTERNATIONAL CONFERENCE ON ADVANCES IN NATURAL AND APPLIED SCIENCES: ICANAS 2016. Author(s), 2016. http://dx.doi.org/10.1063/1.4945841.
Full textReports on the topic "Chickens Embryos Growth"
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Yahav, Shlomo, John Brake, and Orna Halevy. Pre-natal Epigenetic Adaptation to Improve Thermotolerance Acquisition and Performance of Fast-growing Meat-type Chickens. United States Department of Agriculture, September 2009. http://dx.doi.org/10.32747/2009.7592120.bard.
Full textAbstract:
: The necessity to improve broiler thermotolerance and performance led to the following hypothesis: (a) thethermoregulatory-response threshold for heat production can be altered by thermal manipulation (TM) during incubation so as to improve the acquisition of thermotolerance in the post-hatch broiler;and (b) TM during embryogenesis will improve myoblast proliferation during the embryonic and post-hatch periods with subsequent enhanced muscle growth and meat production. The original objectives of this study were as follow: 1. to assess the timing, temperature, duration, and turning frequency required for optimal TM during embryogenesis; 2. to evaluate the effect of TM during embryogenesis on thermoregulation (heat production and heat dissipation) during four phases: (1) embryogenesis, (2) at hatch, (3) during growth, and (4) during heat challenge near marketing age; 3. to investigate the stimulatory effect of thermotolerance on hormones that regulate thermogenesis and stress (T₄, T₃, corticosterone, glucagon); 4. to determine the effect of TM on performance (BW gain, feed intake, feed efficiency, carcass yield, breast muscle yield) of broiler chickens; and 5. to study the effect of TM during embryogenesis on skeletal muscle growth, including myoblast proliferation and fiber development, in the embryo and post-hatch chicks.This study has achieved all the original objectives. Only the plasma glucagon concentration (objective 3) was not measured as a result of technical obstacles. Background to the topic: Rapid growth rate has presented broiler chickens with seriousdifficulties when called upon to efficiently thermoregulate in hot environmental conditions. Being homeotherms, birds are able to maintain their body temperature (Tb) within a narrow range. An increase in Tb above the regulated range, as a result of exposure to environmental conditions and/or excessive metabolic heat production that often characterize broiler chickens, may lead to a potentially lethal cascade of irreversible thermoregulatory events. Exposure to temperature fluctuations during the perinatal period has been shown to lead to epigenetic temperature adaptation. The mechanism for this adaptation was based on the assumption that environmental factors, especially ambient temperature, have a strong influence on the determination of the “set-point” for physiological control systems during “critical developmental phases.” In order to sustain or even improve broiler performance, TM during the period of embryogenesis when satellite cell population normally expand should increase absolute pectoralis muscle weight in broilers post-hatch. Major conclusions: Intermittent TM (39.5°C for 12 h/day) during embryogenesis when the thyroid and adrenal axis was developing and maturing (E7 to E16 inclusive) had a long lasting thermoregulatory effect that improved thermotolerance of broiler chickens exposed to acute thermal stress at market age by lowering their functional Tb set point, thus lowering metabolic rate at hatch, improving sensible heat loss, and significantly decreasing the level of stress. Increased machine ventilation rate was required during TM so as to supply the oxygen required for the periods of increased embryonic development. Enhancing embryonic development was found to be accomplished by a combination of pre-incubation heating of embryos for 12 h at 30°C, followed by increasing incubation temperature to 38°C during the first 3 days of incubation. It was further facilitated by increasing turning frequency of the eggs to 48 or 96 times daily. TM during critical phases of muscle development in the late-term chick embryo (E16 to E18) for 3 or 6 hours (39.5°C) had an immediate stimulatory effect on myoblast proliferation that lasted for up to two weeks post-hatch; this was followed by increased hypertrophy at later ages. The various incubation temperatures and TM durations focused on the fine-tuning of muscle development and growth processes during late-term embryogenesis as well as in post-hatch chickens.
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Halevy, Orna, Zipora Yablonka-Reuveni, and Israel Rozenboim. Enhancement of meat production by monochromatic light stimuli during embryogenesis: effect on muscle development and post-hatch growth. United States Department of Agriculture, June 2004. http://dx.doi.org/10.32747/2004.7586471.bard.
Full textAbstract:
The original objectives were: A. To determine the critical embryonic age for monochromatic green light stimulation. B. To follow the ontogeny of embryos exposed to monochromatic green light vs. darkness. C. To investigate the effects of monochromatic green light illumination on myoblast and fiber development in the embryo. D. To investigate the stimulatory effect of light combinations during embryo and post-hatch periods on growth and meat production. E. To evaluate the direct effect of monochromatic green light on cultured embryonic and adult myoblasts. The overall purpose of this study was to investigate the effect of monochromatic light stimuli during incubation period of broilers on muscle development and satellite cell myogenesis. Based on previous studies (Halevy et al., 1998; Rozenboim et al., 1999) that demonstrated the positive effects of green-light illumination on body and muscle growth, we hypothesized that monochromatic light illumination accelerates embryo and muscle development and subsequently enhances muscle growth and meat production. Thus, further decreases management costs. Under the cooperation of the laboratories at the Hebrew University of Jerusalem and University of Washington we have conducted the following: 1. We have established the critical stage for exposure to green monochromatic light which has the maximal effect on body and muscle growth (Objective A). We report that embryonic day 5 is optimal for starting illumination. The optimal regime of lighting that will eliminate possible heat effects was evaluated by monitoring egg core temperature at various illumination periods. We found that intermitted lighting (15 min. on; 15 min. off) is optimal to avoid heat effects. 2. We have evaluated in detail gross changes in embryo development profile associated to green light stimuli vs. darkness. In addition, we have investigated the stimulatory effect of light combinations during embryo and post-hatch periods on body and muscle growth (Objective B,D). 3. We have studied the expression profile of muscle regulatory proteins during chicken muscle cell differentiation in cultures using newly developed antibodies. This study paved the way for analyzing the expression of these proteins in our photo stimulation experiments (Objective C). 4. We have studied the pattern ofPax7 expression during myogenesis in the posthatch chicken. Experimental chick pectoralis muscles as well adult myoblast cultures were used in this study and the results led us to propose a novel model for satellite cell differentiation and renewal. 5. The effects of monochromatic green light illumination during embryogenesis have been studied. These studies focused on fetal myoblast and satellite cell proliferation and differentiation at pre- and posthatch periods and on the effects on the expression of muscle regulatory proteins which are involved in these processes. In addition, we have analyzed the effect of photo stimulation in the embryo on myofiber development at early posthatch (Objective C). 6. In follow the reviewers' comments we have not conducted Objective E. The information gathered from these studies is of utmost importance both, for understanding the molecular basis of muscle development in the posthatch chicks and for applied approach for future broiler management. Therefore, the information could be beneficial to agriculture in the short term on the one hand and to future studies on chick muscle development in the embryo and posthatch on the other hand.
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Schat, Karel Antoni, Irit Davidson, and Dan Heller. Chicken infectious anemia virus: immunosuppression, transmission and impact on other diseases. United States Department of Agriculture, 2008. http://dx.doi.org/10.32747/2008.7695591.bard.
Full textAbstract:
1. Original Objectives. The original broad objectives of the grant were to determine A) the impact of CAV on the generation of cytotoxic T lymphocytes (CTL) to reticuloendotheliosis virus (REV) (CU), B). the interactions between chicken anemia virus (CAV) and Marek’s disease virus (MDV) with an emphasis on horizontal spread of CAV through feathers (KVI), and C) the impact of CAV infection on Salmonella typhimurium (STM) (HUJI). During the third year and the one year no cost extension the CU group included some work on the development of an antigen-antibody complex vaccine for CAV, which was partially funded by the US Poultry and Egg Association. 2. Background to the topic. CAV is a major pathogen causing clinical disease if maternal antibody-free chickens are infected vertically or horizontally between 1 and 14 days of age. Infection after 3 weeks of age when maternal antibodies are not longer present can cause severe subclinical immunosuppression affecting CTL and cytokine expression. The subclinical immunosuppression can aggravate many diseases including Marek’s disease (MD) and several bacterial infections. 3. Major conclusions and achievements. The overall project contributed in the following ways to the knowledge about CAV infection in poultry. As expected CAV infections occur frequently in Israel causing problems to the industry. To control subclinical infections vaccination may be needed and our work indicates that the development of an antigen-antibody complex vaccine is feasible. It was previously known that CAV can spread vertically and horizontally, but the exact routes of the latter had not been confirmed. Our results clearly show that CAV can be shed into the environment through feathers. A potential interaction between CAV and MD virus (MDV) in the feathers was noted which may interfere with MDV replication. It was also learned that inoculation of 7-day-old embryos causes growth retardation and lesions. The potential of CAV to cause immunosuppression was further examined using CTL responses to REV. CTL were obtained from chickens between 36 and 44 days of age with REV and CAV given at different time points. In contrast to our earlier studies, in these experiments we were unable to detect a direct impact of CAV on REV-specific CTL, perhaps because the CTL were obtained from older birds. Inoculation of CAV at one day of age decreased the IgG antibody responses to inactivated STM administered at 10 days of age. 4. Scientific and Agricultural Implications The impact of the research was especially important for the poultry industry in Israel. The producers have been educated on the importance of the disease through the many presentations. It is now well known to the stakeholders that CAV can aggravate other diseases, decrease productivity and profitability. As a consequence they monitor the antibody status of the breeders so that the maternal antibody status of the broilers is known. Also vaccination of breeder flock that remain antibody negative may become feasible further reducing the negative impact of CAV infection. Vaccination may become more important because improved biosecurity of the breeder flocks to prevent avian influenza and Salmonella may delay the onset of seroconversion for CAV by natural exposure resulting in CAV susceptible broilers lacking maternal antibodies. Scientifically, the research added important information on the horizontal spread of CAV through feathers, the interactions with Salmonella typhimurium and the demonstration that antigen-antibody complex vaccines may provide protective immunity.
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Uni, Zehava, and Peter Ferket. Enhancement of development of broilers and poults by in ovo feeding. United States Department of Agriculture, May 2006. http://dx.doi.org/10.32747/2006.7695878.bard.
Full textAbstract:
The specific objectives of this research were the study of the physical and nutritional properties of the In Ovo Feeding (IOF) solution (i.e. theosmostic properties and the carbohydrate: protein ratio composition). Then, using the optimal solution for determining its effect on hatchability, early nutritional status and intestinal development of broilers and turkey during the last quarter of incubation through to 7 days post-hatch (i.e. pre-post hatch period) by using molecular, biochemical and histological tools. The objective for the last research phase was the determination of the effect of in ovo feeding on growth performance and economically valuable production traits of broiler and turkey flocks reared under practical commercial conditions. The few days before- and- after hatch is a critical period for the development and survival of commercial broilers and turkeys. During this period chicks make the metabolic and physiological transition from egg nutriture (i.e. yolk) to exogenous feed. Late-term embryos and hatchlings may suffer a low glycogen status, especially when oxygen availability to the embryo is limited by low egg conductance or poor incubator ventilation. Much of the glycogen reserve in the late-term chicken embryo is utilized for hatching. Subsequently, the chick must rebuild that glycogen reserve by gluconeogenesis from body protein (mostly from the breast muscle) to support post-hatch thermoregulation and survival until the chicks are able to consume and utilize dietary nutrients. Immediately post-hatch, the chick draws from its limited body reserves and undergoes rapid physical and functional development of the gastrointestinal tract (GIT) in order to digest feed and assimilate nutrients. Because the intestine is the nutrient primary supply organ, the sooner it achieves this functional capacity, the sooner the young bird can utilize dietary nutrients and efficiently grow at its genetic potential and resist infectious and metabolic disease. Feeding the embryo when they consume the amniotic fluid (IOF idea and method) showed accelerated enteric development and elevated capacity to digest nutrients. By injecting a feeding solution into the embryonic amnion, the embryo naturally consume supplemental nutrients orally before hatching. This stimulates intestinal development to start earlier as was exhibited by elevated gene expression of several functional genes (brush border enzymes an transporters , elvated surface area, elevated mucin production . Moreover, supplying supplemental nutrients at a critical developmental stage by this in ovo feeding technology improves the hatchling’s nutritional status. In comparison to controls, administration of 1 ml of in ovo feeding solution, containing dextrin, maltose, sucrose and amino acids, into the amnion of the broiler embryo increased dramatically total liver glycogen in broilers and in turkeys in the pre-hatch period. In addition, an elevated relative breast muscle size (% of broiler BW) was observed in IOF chicks to be 6.5% greater at hatch and 7 days post-hatch in comparison to controls. Experiment have shown that IOF broilers and turkeys increased hatchling weights by 3% to 7% (P<0.05) over non injected controls. These responses depend upon the strain, the breeder hen age and in ovo feed composition. The weight advantage observed during the first week after hatch was found to be sustained at least through 35 days of age. Currently, research is done in order to adopt the knowledge for commercial practice.
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Malkinson, Mertyn, Richard Witter, and Irit Davidson. Reduction of Reticuloendotheliosis in Foundation Breeding Flocks of Chickens: A Combined Immunological and Molecular Biological Approach. United States Department of Agriculture, February 1996. http://dx.doi.org/10.32747/1996.7613026.bard.
Full textAbstract:
Reticuloendotheliosis virus (REV) is an avian retrovirus that can cause immunosuppression, growth retardation and tumors. An attempt to define the extent of the economic damage to the poultry industry that it causes is discussed in this report. In addition to losses experienced by commercial laying flocks, reduced rates of hatchability and embryo developmental disorders were demonstrable due to vertical transmission of the virus. I. Eradication of REV In this project a comprehensive national program was applied for the eradication of REV from Israeli breeding stocks by the elimination of antibody-positive birds from the breeding program. The prevention of REV-infected breeders entering Israel was also implemented by serological examination of imported day-old chickens and turkeys for maternal antibody. At the same time commercial breeding flocks in Israel were surveyed routinely to measure the extent of environmental exposure to REV throughout Israel. II. Economic factors associated with vertical transmission on breeders and progeny It was observed that on some poultry farms exposure of breeding flocks to viral infection, if it occurs when the birds are immunocompetent, leads only to a seroconvertion event. In these flocks no differences were demonstrated between the performances of seronegative and seropositive birds. When the F1 generation was selected according to seronegativity of the parents, all the progeny were seronegative, indicating that tolerantly infected birds did not form a significant proportion of the parent flock. In sharp contrast, breeding flocks that became exposed to the virus about the point of lay or during the laying period, shed virus vertically for a brief period of time through the egg. Our epizootiological observations lead us to conclude that the progeny (laying pullets) becomes tolerantly infected and are immunosuppressed as they increase in age. Increased mortality and susceptibility to intercurrent diseases were recorded.
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Yahav, Shlomo, John Brake, and Noam Meiri. Development of Strategic Pre-Natal Cycling Thermal Treatments to Improve Livability and Productivity of Heavy Broilers. United States Department of Agriculture, December 2013. http://dx.doi.org/10.32747/2013.7593395.bard.
Full textAbstract:
The necessity to improve broiler thermotolerance and live performance led to the following hypothesis: Appropriate comprehensive incubation treatments that include significant temperature management changes will promote angiogenesis and will improve acquisition of thermotolerance and carcass quality of heavy broilers through epigenetic adaptation. It was based on the following questions: 1. Can TM during embryogenesis of broilers induce a longer-lasting thermoregulatory memory (up to marketing age of 10 wk) that will improve acquisition of thermotolerance as well as increased breast meat yield in heavy broilers? 2. The improved sensible heat loss (SHL) suggests an improved peripheral vasodilation process. Does elevated temperature during incubation affect vasculogenesis and angiogenesis processes in the chick embryo? Will such create subsequent advantages for heavy broilers coping with adverse hot conditions? 3. What are the changes that occur in the PO/AH that induce the changes in the threshold response for heat production/heat loss based on the concept of epigenetic temperature adaptation? The original objectives of this study were as follow: a. to assess the improvement of thermotolerance efficiency and carcass quality of heavy broilers (~4 kg); b. toimproveperipheral vascularization and angiogenesis that improve sensible heat loss (SHL); c. to study the changes in the PO/AH thermoregulatory response for heat production/losscaused by modulating incubation temperature. To reach the goals: a. the effect of TM on performance and thermotolerance of broilers reared to 10 wk of age was studied. b. the effect of preincubation heating with an elevated temperature during the 1ˢᵗ 3 to 5 d of incubation in the presence of modified fresh air flow coupled with changes in turning frequency was elucidated; c.the effect of elevated temperature on vasculogenesis and angiogenesis was determined using in ovo and whole embryo chick culture as well as HIF-1α VEGF-α2 VEGF-R, FGF-2, and Gelatinase A (MMP2) gene expression. The effects on peripheral blood system of post-hatch chicks was determined with an infrared thermal imaging technique; c. the expression of BDNF was determined during the development of the thermal control set-point in the preoptic anterior hypothalamus (PO/AH). Background to the topic: Rapid growth rate has presented broiler chickens with seriousdifficulties when called upon to efficiently thermoregulate in hot environmental conditions. Being homeotherms, birds are able to maintain their body temperature (Tb) within a narrow range. An increase in Tb above the regulated range, as a result of exposure to environmental conditions and/or excessive metabolic heat production that often characterize broiler chickens, may lead to a potentially lethal cascade of irreversible thermoregulatory events. Exposure to temperature fluctuations during the perinatal period has been shown to lead to epigenetic temperature adaptation. The mechanism for this adaptation was based on the assumption that environmental factors, especially ambient temperature, have a strong influence on the determination of the “set-point” for physiological control systems during “critical developmental phases.” Recently, Piestunet al. (2008) demonstrated for the first time that TM (an elevated incubation temperature of 39.5°C for 12 h/d from E7 to E16) during the development/maturation of the hypothalamic-hypophyseal-thyroid axis (thermoregulation) and the hypothalamic-hypophyseal-adrenal axis (stress) significantly improved the thermotolerance and performance of broilers at 35 d of age. These phenomena raised two questions that were addressed in this project: 1. was it possible to detect changes leading to the determination of the “set point”; 2. Did TM have a similar long lasting effect (up to 70 d of age)? 3. Did other TM combinations (pre-heating and heating during the 1ˢᵗ 3 to 5 d of incubation) coupled with changes in turning frequency have any performance effect? The improved thermotolerance resulted mainly from an efficient capacity to reduce heat production and the level of stress that coincided with an increase in SHL (Piestunet al., 2008; 2009). The increase in SHL (Piestunet al., 2009) suggested an additional positive effect of TM on vasculogenesis and angiogensis. 4. In order to sustain or even improve broiler performance, TM during the period of the chorioallantoic membrane development was thought to increase vasculogenesis and angiogenesis providing better vasodilatation and by that SHL post-hatch.