Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping gen...Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping genes typically used for the normalization of quantitative real-time PCR (QPCR) analysis in mammals were compared in CEFs infected with H5N1 AIV to determine the most reliable reference genes in this system.CEFs cultured from 10-day-old SPF chicken embryos were infected with 100 TCID50 of H5N1 AIV and harvested at 3,12,24 and 30 hours post-infection.The expression levels of the eleven reference genes in infected and uninfected CEFs were determined by real-time PCR.Based on expression stability and expression levels,our data suggest that the ribosomal protein L4 (RPL4) and tyrosine 3-monooxygenase tryptophan 5-monooxygenase activation protein zeta polypeptide (YWHAZ) are the best reference genes to use in the study of host cell response to H5N1 AIV infection.However,for the study of replication levels of H5N1 AIV in CEFs,the β-actin gene (ACTB) and the ribosomal protein L4 (RPL4) gene are the best references.展开更多
Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts(CEF) is a common method to develop attenuated live vaccines with full security.Canine distemper virus(CDV) also does this,but the mecha...Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts(CEF) is a common method to develop attenuated live vaccines with full security.Canine distemper virus(CDV) also does this,but the mechanisms and particular receptors remain unclear.Virus overlay protein blot assays were carried out on CEF membrane proteins,which were extracted respectively with a Mem-PER TM kit,a radioimmunoprecipitation assay buffer or a modified co-immunoprecipitation method,and revealed a common 57 kDa positive band that differed from the 42-kDa positive band in Vero cells and also from those receptors reported in lymphocytes and 293 cells,indicating a receptor diversity of CDV and the possibility of the 57-kDa protein acting as a receptor that is involved in adaptive infection of CDV Kunming strain to CEF.展开更多
In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing ...In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.展开更多
Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepard from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1. 2 %, 3 %, 12%...Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepard from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1. 2 %, 3 %, 12%, and 48%, respectively) by gavage up to their onsets of puberty.The rats in the control group were treated with distilled water. However, Ji-Pei-Jing treatment exerted some effects on sexual mauration in the immature female rats. Essentially, the effects showed a dose-response tendency with an inverted 'U' shape.The age of vopnal opening for gnup treated with Ji-Pei-Jing was significantly earier than that to the control. Its uterus weight/b. w. ratio also significantly increased on day 30 and at the first estrus. There were significantly increases in the adrenal weight/b. w. raio of 30-day-old rats that were treated with 3%, 12%, and 48% Ji-Pei-Jing. The rats treated with 48% Ji-Pei-Jing had significantly lesser ovary weight.b.w. radio on day 30, too. The rats treated with Ji-Pei-Jing could normally ovulate at the first estrus, and no significant differences were observed during estrous cycles.The effects of PCE on serum levels of K, P, LH in 30-day-old nds and FSH in 28-day-old ras were elevated significantly by 3 % Ji-Pei-Jing treatment. It appeare that the effects of PCE result from interaction of contained complex physiologically active substances. Steriods, especially estradio-17β,possibly Play a key role, and polpeptide hormones may also exert important effects.展开更多
[Objective] To observe whether fowlpox virus （FPV） can proliferate in chicken embryo passage fibroblasts or not and then try to use chicken embryo passage fibroblasts to replace primary chicken embryo cells for FPV ...[Objective] To observe whether fowlpox virus （FPV） can proliferate in chicken embryo passage fibroblasts or not and then try to use chicken embryo passage fibroblasts to replace primary chicken embryo cells for FPV culture. [Method] Primary chicken embryo fibroblasts were prepared and subcultured. After FPV were inoculated on the 20th passage fibroblasts, cytopathy was observed. Then, the FPV culture was identified and determined quantificationally. [Result] Specific cytopathy appeared in the FPV-inoculated chicken embryo passage fibroblasts. The titer of the yielded FPV culture reached the standard for production of fowl pox vaccine. Further analysis reveals that the chorioallantoic membrane lesions were caused by FPV. [ Conclusion] FPV can reproduce in chicken embryo passage fibroblasts, and the Uter of FPV cell culture can meet the pro- duction requirements of fowl pox vaccine.展开更多
The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying ...The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying chicken interferon via allaotoic sack, while 10-day-old chicken embryos were inoculated with NDV F48E10, and in vivo protective efficacy of interferon on chichen embryos was studied. The results showed that the recombinant freeze-drying chicken interferon at the dose of 1.28 mg/embryo reached the protection ratio of 90% on chicken embryo infected by F48E10.展开更多
Vascular injury or interruption may play a role in vertebrate limb teratogenesis. Since 5fluoro- 2'- deoxyuridine (FdU) can cause vascular injury in the murine limb and skull prior to the appearance of skeletal ma...Vascular injury or interruption may play a role in vertebrate limb teratogenesis. Since 5fluoro- 2'- deoxyuridine (FdU) can cause vascular injury in the murine limb and skull prior to the appearance of skeletal malformations in these structures, we studied the effects of this chemical on skeletal development in the chick embryo and noted any vascular injury. The yolk sacs of day three ehick embryos (Hamburger and Hamilton states 17-19) were injected with solutions of vary concentrations of FdU in saline. The embryos developed until the 10th day of incubation when they were fixed for study. Uninjected, saline injected, and sham injected control embryo were similarly fixed. Upon gross inspection, frequent diffuse and saccular hernatomas, as well as fluid-filled blisters, were noted in the limbs of embryos treated with FdU. After the embryos were fixed and cleared, and the skeletons stained, significant skeletal malformations were observed in these limbs. Bony elements of both the upper and lower limbs were affected in at least some of the embryos. The combination of FdU-induced hematomas and blisters with associated skeletal malformations in the same regions of some embryos suggests a relationship between these phenomena.展开更多
In this paper, the eggs＇ weight, quality characteristics （ albumen density, shell quality, yolk size）, and egg weight loss during incubation having impact on volume of allantoin-anmiotic fluid are considered. The m...In this paper, the eggs＇ weight, quality characteristics （ albumen density, shell quality, yolk size）, and egg weight loss during incubation having impact on volume of allantoin-anmiotic fluid are considered. The major parameters that should be taken into account when creating specialized population of chickens for the production of DEC （ developing embryos of chickens） are determined.展开更多
Medium-chain fatty acids and their derivatives are natural ingredients that support immunological functions in animals.The effects of glycerol monolaurate(GML)on intestinal innate immunity and associated molecular mec...Medium-chain fatty acids and their derivatives are natural ingredients that support immunological functions in animals.The effects of glycerol monolaurate(GML)on intestinal innate immunity and associated molecular mechanisms were investigated using a chicken embryo model.Sixty-four Arbor Acres broiler embryos were randomly allocated into four groups.On embryonic day 17.5,the broiler embryos were administered with 9 mg of GML,which was followed by a 12-h incubation period and a12-h challenge with 32μg of lipopolysaccharide(LPS).On embryonic day 18.5,the jejunum and ileum were harvested.Results indicated that GML reversed the LPS-induced decline in villus height and upregulated the expression of mucin 2(P<0.05).GML decreased LPS-induced malondialdehyde production and boosted antioxidant enzyme activity(P<0.05).GML alleviated LPS-stimulated intestinal secretion of interleukin(IL)-1β,IL-6,and tumor necrosis factor-a(TNF-a)(P<0.05).GML also normalized LPS-induced changes in the gene expression of Toll-like receptor 4,nuclear factor kappa-B p65(NF-κB p65),cyclooxygenase-2,NOD-like receptor protein 3,IL-18,zonula occludens 1,and occludin(P<0.05).GML enhanced as well the expression of AMP-activated protein kinase a1 and claudin 1(P<0.05).In conclusion,GML improved intestinal morphology and antioxidant status by alleviating inflammatory responses and modulating NF-κB signaling in LPS-challenged broiler embryos.展开更多
RNA interference(RNAi)technology is a powerful tool for identifying gene functions.Chicken embryo fibroblast(CEF)is an ideal model for studying the interaction between avian viruses and their hosts.To establish a meth...RNA interference(RNAi)technology is a powerful tool for identifying gene functions.Chicken embryo fibroblast(CEF)is an ideal model for studying the interaction between avian viruses and their hosts.To establish a methodological platform for RNAi studies in CEF,three plasmid vectors expressing short hairpin RNAs(shRNAs)targeted against the Newcastle disease virus(NDV)NP gene were constructed.One of them,ndv1,was proven effective on blocking viral replication in CEF and chicken embryos.Four hours prior to infection with NDV,the CEF was transfected with the plasmids by Silent-fect.An unrelated shRNA sequence(HK)was used in mock transfection.The expression of a potent shRNA resulted in up to 2.3,21.1 and 9.8 fold decreases in NP gene expression at 3,6 and 9 h post infection in CEF,respectively.The ndv1 was able to completely inhibit the replication of the virus in CEF within 48 post infection.Furthermore,the pathological changes in CEF caused by NDV were delayed,and the degree of pathological changes was lighter compared with the mock transfection in the presence of ndv1.When the complex of shRNASilent-fect and NDV was co-injected into the allantoic cavity of 10-day-old embryonated eggs with 10^(5) or 10^(6) ELD50 NDV,NDV replication was decreased by 94.14% and 62.15% after 17 h,respectively.These findings suggest that the newly synthesized NP protein is critical for NDV transcription and replication and provide a basis for identifying the functions of viral genes and screening for effective siRNAs against viruses in CEF and chicken embryo by RNAi.展开更多
In this study, a protocol was developed to identify the sex of earlier embryos of chicken （♂）-quail （♀） hybrids and successfully tested the sex proportion of each period （66-120 h）. We acquired cross bred eggs...In this study, a protocol was developed to identify the sex of earlier embryos of chicken （♂）-quail （♀） hybrids and successfully tested the sex proportion of each period （66-120 h）. We acquired cross bred eggs by artificial insemination, hatched them in the same batch according to the standard hatching condition of chicken, and collected earlier living embryos at 66, 72, 78, 84, 90, 96, 102, 108, 114, and 120 h randomly. We adopted RT-PCR protocol and multiple PCR, made the known sex quail as the external control, employed fl-actin as the internal control, and used primers that were designed according to conservative area of gene Wpkci of quail to identify the sex of earlier hybrid embryos. The results indicated that the primer of Wpkci can be used to identify the sex of hybrid embryos accurately; there were more male than female in earlier embryos, the sex proportion of earlier embryos compared with academic numerical value was significantly different （P〈0.01）, and there was no difference between different periods （P〉0.05）. In the present study, we concluded that a simple, fast, credible and stable protocol to identify the sex of earlier hybrids embryos had been established by using primer of Wpkci; in earlier embryos, the death rate of female was higher than that of male and there was no fluctuant peak.展开更多
Studies of receptor-mediated lipoprotein metabolic pathways in avian species have revealed that physiological intricacies of specific cell types are highly analogous to those in mammals. A prime example for the power ...Studies of receptor-mediated lipoprotein metabolic pathways in avian species have revealed that physiological intricacies of specific cell types are highly analogous to those in mammals. A prime example for the power of com- parative studies across different animal kingdoms, elucidated in the chicken, is that the expression of different lipo- protein receptors in somatic cells and oocytes are the key to oocyte growth. In avian species, yolk precursor transport from the hen＇s liver to rapidly growing oocytes and the subsequent transfer of yolk nutrients via the yolk sac to the developing embryo are highly efficient processes. Oocytes grow from a diameter of 5 mm to 2.5-3 cm in only 7 days, and the yolk sac transfers nutrients from the yolk stored in the mature oocyte to the embryo within just 2 weeks. The underlying key transport mechanism is receptor-mediated endocytosis of macromolecules, i.e., of hepatically synthesized yolk precursors for oocyte growth, and of mature yolk components for embryo nutrition, respectively. Recently, the receptors involved, as well as the role of lipoprotein synthesis in the yolk sac have been identified. As outlined here, lipoprotein degradation/resynthesis cycles and the expression of lipoprotein receptors are not only coordinated with the establishment of the tbllicular architecture embedding the oocyte, but also with the generation of the yolk sac vasculature essential for nutrient transfer to the embryo.展开更多
基金National "11th Five-year Plan" Scientific and Technical Supporting Programs (2006BAD06A11)
文摘Chicken embryo fibroblasts (CEFs) are among the most commonly used cells for the study of interactions between chicken hosts and H5N1 avian influenza virus (AIV).In this study,the expression of eleven housekeeping genes typically used for the normalization of quantitative real-time PCR (QPCR) analysis in mammals were compared in CEFs infected with H5N1 AIV to determine the most reliable reference genes in this system.CEFs cultured from 10-day-old SPF chicken embryos were infected with 100 TCID50 of H5N1 AIV and harvested at 3,12,24 and 30 hours post-infection.The expression levels of the eleven reference genes in infected and uninfected CEFs were determined by real-time PCR.Based on expression stability and expression levels,our data suggest that the ribosomal protein L4 (RPL4) and tyrosine 3-monooxygenase tryptophan 5-monooxygenase activation protein zeta polypeptide (YWHAZ) are the best reference genes to use in the study of host cell response to H5N1 AIV infection.However,for the study of replication levels of H5N1 AIV in CEFs,the β-actin gene (ACTB) and the ribosomal protein L4 (RPL4) gene are the best references.
基金supported by a grant from Yunnan Provincial Education Board(08C0070)a grant from Yunnan Provincial Program for Introducing High-level Scientists (2009CI125)
文摘Inducing animal viruses to adapt to chicken embryos or chicken embryo fibroblasts(CEF) is a common method to develop attenuated live vaccines with full security.Canine distemper virus(CDV) also does this,but the mechanisms and particular receptors remain unclear.Virus overlay protein blot assays were carried out on CEF membrane proteins,which were extracted respectively with a Mem-PER TM kit,a radioimmunoprecipitation assay buffer or a modified co-immunoprecipitation method,and revealed a common 57 kDa positive band that differed from the 42-kDa positive band in Vero cells and also from those receptors reported in lymphocytes and 293 cells,indicating a receptor diversity of CDV and the possibility of the 57-kDa protein acting as a receptor that is involved in adaptive infection of CDV Kunming strain to CEF.
基金supported by the National Natural Science Foundation of China (31472087)the Research and Innovation Program for Graduate Cultivation of Jiangsu Proviance,China in 2010
文摘In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation. Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice. However, there are few studies about the effect of the different injection site and dosage on chicken embryos. The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model. Freshly laid eggs （Rugao yellow chicken） were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively. Egg hatching rate was recorded and compared among injection sites and different doses. A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed. The SPSS （statistical package for the social science） software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages. The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses （P〈0.05）. The hatchability of the blunt end injection group was significantly higher than that of the other two sites. The egg hatching rate decreased with increased saline doses. The egg hatching rate of the 100 pL saline injection group was higher than the 200 and 300 μL dosage groups. Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 μL to minimize damage to the egg.
文摘Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepard from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1. 2 %, 3 %, 12%, and 48%, respectively) by gavage up to their onsets of puberty.The rats in the control group were treated with distilled water. However, Ji-Pei-Jing treatment exerted some effects on sexual mauration in the immature female rats. Essentially, the effects showed a dose-response tendency with an inverted 'U' shape.The age of vopnal opening for gnup treated with Ji-Pei-Jing was significantly earier than that to the control. Its uterus weight/b. w. ratio also significantly increased on day 30 and at the first estrus. There were significantly increases in the adrenal weight/b. w. raio of 30-day-old rats that were treated with 3%, 12%, and 48% Ji-Pei-Jing. The rats treated with 48% Ji-Pei-Jing had significantly lesser ovary weight.b.w. radio on day 30, too. The rats treated with Ji-Pei-Jing could normally ovulate at the first estrus, and no significant differences were observed during estrous cycles.The effects of PCE on serum levels of K, P, LH in 30-day-old nds and FSH in 28-day-old ras were elevated significantly by 3 % Ji-Pei-Jing treatment. It appeare that the effects of PCE result from interaction of contained complex physiologically active substances. Steriods, especially estradio-17β,possibly Play a key role, and polpeptide hormones may also exert important effects.
基金Liaoning Agricultural College for providing test site and fund for Doctors of Liaoning Medical College
文摘[Objective] To observe whether fowlpox virus （FPV） can proliferate in chicken embryo passage fibroblasts or not and then try to use chicken embryo passage fibroblasts to replace primary chicken embryo cells for FPV culture. [Method] Primary chicken embryo fibroblasts were prepared and subcultured. After FPV were inoculated on the 20th passage fibroblasts, cytopathy was observed. Then, the FPV culture was identified and determined quantificationally. [Result] Specific cytopathy appeared in the FPV-inoculated chicken embryo passage fibroblasts. The titer of the yielded FPV culture reached the standard for production of fowl pox vaccine. Further analysis reveals that the chorioallantoic membrane lesions were caused by FPV. [ Conclusion] FPV can reproduce in chicken embryo passage fibroblasts, and the Uter of FPV cell culture can meet the pro- duction requirements of fowl pox vaccine.
文摘The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying chicken interferon via allaotoic sack, while 10-day-old chicken embryos were inoculated with NDV F48E10, and in vivo protective efficacy of interferon on chichen embryos was studied. The results showed that the recombinant freeze-drying chicken interferon at the dose of 1.28 mg/embryo reached the protection ratio of 90% on chicken embryo infected by F48E10.
文摘Vascular injury or interruption may play a role in vertebrate limb teratogenesis. Since 5fluoro- 2'- deoxyuridine (FdU) can cause vascular injury in the murine limb and skull prior to the appearance of skeletal malformations in these structures, we studied the effects of this chemical on skeletal development in the chick embryo and noted any vascular injury. The yolk sacs of day three ehick embryos (Hamburger and Hamilton states 17-19) were injected with solutions of vary concentrations of FdU in saline. The embryos developed until the 10th day of incubation when they were fixed for study. Uninjected, saline injected, and sham injected control embryo were similarly fixed. Upon gross inspection, frequent diffuse and saccular hernatomas, as well as fluid-filled blisters, were noted in the limbs of embryos treated with FdU. After the embryos were fixed and cleared, and the skeletons stained, significant skeletal malformations were observed in these limbs. Bony elements of both the upper and lower limbs were affected in at least some of the embryos. The combination of FdU-induced hematomas and blisters with associated skeletal malformations in the same regions of some embryos suggests a relationship between these phenomena.
基金Supported by the Major Agricultural Projects of Major Scientific and Technological Projects of Department of Science and Technology of Zhejiang Province(2014C02001)The Zhejiang Agricultural Science and Technology Achievements Transformation Project"Featured Poultry Genetic Resources in Zhejiang Province-Lingkun Chicken Demonstration"
文摘In this paper, the eggs＇ weight, quality characteristics （ albumen density, shell quality, yolk size）, and egg weight loss during incubation having impact on volume of allantoin-anmiotic fluid are considered. The major parameters that should be taken into account when creating specialized population of chickens for the production of DEC （ developing embryos of chickens） are determined.
基金supported by the National Natural Science Foundation of China(32272910)the Natural Science Foundation of Shandong Province(ZR2020MC170).
文摘Medium-chain fatty acids and their derivatives are natural ingredients that support immunological functions in animals.The effects of glycerol monolaurate(GML)on intestinal innate immunity and associated molecular mechanisms were investigated using a chicken embryo model.Sixty-four Arbor Acres broiler embryos were randomly allocated into four groups.On embryonic day 17.5,the broiler embryos were administered with 9 mg of GML,which was followed by a 12-h incubation period and a12-h challenge with 32μg of lipopolysaccharide(LPS).On embryonic day 18.5,the jejunum and ileum were harvested.Results indicated that GML reversed the LPS-induced decline in villus height and upregulated the expression of mucin 2(P<0.05).GML decreased LPS-induced malondialdehyde production and boosted antioxidant enzyme activity(P<0.05).GML alleviated LPS-stimulated intestinal secretion of interleukin(IL)-1β,IL-6,and tumor necrosis factor-a(TNF-a)(P<0.05).GML also normalized LPS-induced changes in the gene expression of Toll-like receptor 4,nuclear factor kappa-B p65(NF-κB p65),cyclooxygenase-2,NOD-like receptor protein 3,IL-18,zonula occludens 1,and occludin(P<0.05).GML enhanced as well the expression of AMP-activated protein kinase a1 and claudin 1(P<0.05).In conclusion,GML improved intestinal morphology and antioxidant status by alleviating inflammatory responses and modulating NF-κB signaling in LPS-challenged broiler embryos.
基金The study was supported by the National Science and Technology Foundation during the 10th Five-Year Plan Period(2004BA519A58)Applied Basic Research Program of Sichuan Province(05JY029-007-5).
文摘RNA interference(RNAi)technology is a powerful tool for identifying gene functions.Chicken embryo fibroblast(CEF)is an ideal model for studying the interaction between avian viruses and their hosts.To establish a methodological platform for RNAi studies in CEF,three plasmid vectors expressing short hairpin RNAs(shRNAs)targeted against the Newcastle disease virus(NDV)NP gene were constructed.One of them,ndv1,was proven effective on blocking viral replication in CEF and chicken embryos.Four hours prior to infection with NDV,the CEF was transfected with the plasmids by Silent-fect.An unrelated shRNA sequence(HK)was used in mock transfection.The expression of a potent shRNA resulted in up to 2.3,21.1 and 9.8 fold decreases in NP gene expression at 3,6 and 9 h post infection in CEF,respectively.The ndv1 was able to completely inhibit the replication of the virus in CEF within 48 post infection.Furthermore,the pathological changes in CEF caused by NDV were delayed,and the degree of pathological changes was lighter compared with the mock transfection in the presence of ndv1.When the complex of shRNASilent-fect and NDV was co-injected into the allantoic cavity of 10-day-old embryonated eggs with 10^(5) or 10^(6) ELD50 NDV,NDV replication was decreased by 94.14% and 62.15% after 17 h,respectively.These findings suggest that the newly synthesized NP protein is critical for NDV transcription and replication and provide a basis for identifying the functions of viral genes and screening for effective siRNAs against viruses in CEF and chicken embryo by RNAi.
文摘In this study, a protocol was developed to identify the sex of earlier embryos of chicken （♂）-quail （♀） hybrids and successfully tested the sex proportion of each period （66-120 h）. We acquired cross bred eggs by artificial insemination, hatched them in the same batch according to the standard hatching condition of chicken, and collected earlier living embryos at 66, 72, 78, 84, 90, 96, 102, 108, 114, and 120 h randomly. We adopted RT-PCR protocol and multiple PCR, made the known sex quail as the external control, employed fl-actin as the internal control, and used primers that were designed according to conservative area of gene Wpkci of quail to identify the sex of earlier hybrid embryos. The results indicated that the primer of Wpkci can be used to identify the sex of hybrid embryos accurately; there were more male than female in earlier embryos, the sex proportion of earlier embryos compared with academic numerical value was significantly different （P〈0.01）, and there was no difference between different periods （P〉0.05）. In the present study, we concluded that a simple, fast, credible and stable protocol to identify the sex of earlier hybrids embryos had been established by using primer of Wpkci; in earlier embryos, the death rate of female was higher than that of male and there was no fluctuant peak.
基金supported by Research Grants from the Austrian Science Fundthe Austrian National Bankthe Herzfelder Family Endowment
文摘Studies of receptor-mediated lipoprotein metabolic pathways in avian species have revealed that physiological intricacies of specific cell types are highly analogous to those in mammals. A prime example for the power of com- parative studies across different animal kingdoms, elucidated in the chicken, is that the expression of different lipo- protein receptors in somatic cells and oocytes are the key to oocyte growth. In avian species, yolk precursor transport from the hen＇s liver to rapidly growing oocytes and the subsequent transfer of yolk nutrients via the yolk sac to the developing embryo are highly efficient processes. Oocytes grow from a diameter of 5 mm to 2.5-3 cm in only 7 days, and the yolk sac transfers nutrients from the yolk stored in the mature oocyte to the embryo within just 2 weeks. The underlying key transport mechanism is receptor-mediated endocytosis of macromolecules, i.e., of hepatically synthesized yolk precursors for oocyte growth, and of mature yolk components for embryo nutrition, respectively. Recently, the receptors involved, as well as the role of lipoprotein synthesis in the yolk sac have been identified. As outlined here, lipoprotein degradation/resynthesis cycles and the expression of lipoprotein receptors are not only coordinated with the establishment of the tbllicular architecture embedding the oocyte, but also with the generation of the yolk sac vasculature essential for nutrient transfer to the embryo.
