The dynamic information of 331 animal genetic resources in 17 important animal genetic resource provinces (regions) was analyzed. According to the population inbreeding coefficient, combining with the information of p...The dynamic information of 331 animal genetic resources in 17 important animal genetic resource provinces (regions) was analyzed. According to the population inbreeding coefficient, combining with the information of population dynamic change trend and cross degree, these genetic resources for threatened degrees were classified. The results indicated that the population size of 138 breeds had increased, 147 breeds had decreased, 3 breeds were constant, 7 breeds (or varieties) were extinct, 9 breeds (or varieties) were critically endangered and needed urgently conserve, 50 breeds (or varieties) were endangered and should be conserved. We put forward a conservation and utilization plan for animal genetic resources.展开更多
A single nucleotide polymorphism （SNP） of 805 bp region in the intron 6 of transfor- ming growth factor β1 （TGF-fll） gene was identified by polymerase chain reaction-single-strand composi- tion polymorphism （PCR...A single nucleotide polymorphism （SNP） of 805 bp region in the intron 6 of transfor- ming growth factor β1 （TGF-fll） gene was identified by polymerase chain reaction-single-strand composi- tion polymorphism （PCR-SSCP） in 196 sheep among Small-tailed Han sheep, Tong sheep, Tan sheep and Oula sheep. Comparative sequence analysis of cloned products revealed an AGAC deletion at 294 bases up-stream of exon 7 of the TGF-βI gene （ site 14201 in gi76871756）. Statistical results of the genotype and allele frequencies in different breeds showed that gen- otype AB was dominant in the Small-tailed Han sheep. Genotype BB, however, was in majority in low- fecundity sheep. The results of a Chi-square test indi- cated that all the populations were in Hardy-Weinberg equilibrium.展开更多
After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits...After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits and plasma lipids were determined,and effects of interaction between genotype and nutrition on AF and its correlated traits were studied.1) It was efficient to select against AF on the basis of plasma VLDL concentration.The indirect response of gizzard fat was the greatest,and that of liver fat was the second.AF was decreased,whereas liver fat was increased,feed conversion efficiency during growing period were improved, body weight and meat traits were both not influenced by selecting for low plasma VLDL concentration.2) Nutrition had significant effect on fat deposition and growth performance.Interaction between line and diet had evident effect on AF and its correlated traits.In general,diet had greater effect on H-VLDL line than L-VLDL line,namely chickens of L-VLDL line were less sensitive to diet than those of H-VLDL line.3) Due to high coefficients of variation of plasma VLDL and AF in H-VLDL and L-VLDL lines in the first generation.It will be possible that plasma VLDL is to be selected continuously to breed low fat line of broiler chickens of which the feed conversion efficiency is much better.Moreover,family combined with individual selection should be adopted during future generation selection and breeding because of significant family difference in plasma VLDL concentration.展开更多
The reproductive performance and abdominal fat of the high VLDL (H-VLDL) and low VLDL (L-VLDL) lines were studied after divergent selection for plasma very low density lipoprotein (VLDL) concentration in broiler chick...The reproductive performance and abdominal fat of the high VLDL (H-VLDL) and low VLDL (L-VLDL) lines were studied after divergent selection for plasma very low density lipoprotein (VLDL) concentration in broiler chickens at 8 weeks of age. It was shown that the main reproductive traits were higher in L-VLDL line than H-VLDL line. The beneficial correlated responses of the reproductive traits were produced by the selection for plasma VLDL. 1) Plasma VLDL concentration was significantly correlated with abdominal fat (r=0.50, P<0.01), ahich was higher than that with plasma triglyceride concentration. There was a significant difference in abdominal fat between both lines but age increase or food restriction may decrease this difference. The H-VLDL line had about twice as much abdominal fat as had L-VLDL at 8 weeks of age, while its mean body weight was similar to that of the L-VLDL line from birtl to the end of laying. 2) Mortality from apparently stress-related causes by food restriction for H-VLDL line females began to increase from 15 weeks of age and was 21% (38/180) higher compared with 13% (23/180) for L-VLDL line females. 3) Age of 5% Lying for L-VLDL line was 3 days less than that of H-VLDL line, age of 50% Lying was 37 days less for L-VLDL line than H-VLDL line, and the age of laying peak was similiar in both lines. Rate of lay at peak in L-VLDL and H-VLDL lines were 70.3%, 66.4%, respectively. 4) Fertility rate in L-VLDL line was significantly higher than that of H-VLDL line at 27 weeks of age (P=0.01) and there was a little difference in fertility rates between H-VLDL and L-VLDL line during late laying period. There were no significant differences between H-VLDL and L-VLDL lines in of day-old healthy the numbers chicks and hatchabilities of fertile and total eggs wheres mean numbers of healthy day-old chicks per hen were more is L-VLDL line than in H-VLDL line. 5) Under food restriction, egg production was higher in L-VLDL line than in H-VLDL line. It should be emphasized that the rate and amount of egg production in L-VLDL line were both significant higher than in H-VLDL line during early laying period (from 23 to 43 weeks of age, P<0.01). The mean egg production of LF line hens was ll eggs more than that of HF line ones throughtout the laying period (from 23 to 62 weeks of age). 6) Eggs in L-VLDL line were slightly heavier than those in H-VLDL line. Feed conversion (FC) ratio for L-VLDL line was lower than that in H-VLDL line betwen 23 and 62 weeks of age (5.01 and 5.46, respectively), especially FC ratio of L-VLDL line was significantly lower than that of HF line during 23 and 43 weeks of age (P<0.01). Also FC efficiency of breeding hens was higher in L-VLDL line than in H-VLDL line.展开更多
Bovine fetal oviduct epithelial cells were transfected with constructed double marker selective vector(pCE-EGFP-IRES-Neo-dNdB) containing the enhanced green fluorescent protein (EGFP) and neomycin-resistant(Neo^r) gen...Bovine fetal oviduct epithelial cells were transfected with constructed double marker selective vector(pCE-EGFP-IRES-Neo-dNdB) containing the enhanced green fluorescent protein (EGFP) and neomycin-resistant(Neo^r) genes by electroporation, and a transgenic cell line was obtained. Somatic cell nuclear transfer (SCNT) was cartied out using the transgenic cells as nuclei donor. A total of 424 SCNT embryos were reconstructed and 208 (49.1%) of them developed to blastocyst stage. 17 blastocysts on D 7 after reconstruction were transferred to 17 surrogate calves,and 5 (29.4%) recipients were found to be pregnant. Three of them maintained to term and delivered three cloned calves.PCR and Southern blot analysis confirmed the integration of transgene in all of the three cloned calves. In addition, expression of EGFP was detected in biopsy isolated from the transgenic cloned calves and fibroblasts derived from the biopsy. Our results suggest that transgenic calves could be efficiently produced by SCNT using transgenic cells as nuclei donor. Furthermore, all cloned animals could be ensured to be transgenic by efficiently pre-screening transgenic cells and SCNT embryos using the constructed double marker selective vector.展开更多
文摘The dynamic information of 331 animal genetic resources in 17 important animal genetic resource provinces (regions) was analyzed. According to the population inbreeding coefficient, combining with the information of population dynamic change trend and cross degree, these genetic resources for threatened degrees were classified. The results indicated that the population size of 138 breeds had increased, 147 breeds had decreased, 3 breeds were constant, 7 breeds (or varieties) were extinct, 9 breeds (or varieties) were critically endangered and needed urgently conserve, 50 breeds (or varieties) were endangered and should be conserved. We put forward a conservation and utilization plan for animal genetic resources.
基金supported by the National Natural Science Foundation of China(No.30270949)"863"Plan(No.2006AA10Z199)
文摘A single nucleotide polymorphism （SNP） of 805 bp region in the intron 6 of transfor- ming growth factor β1 （TGF-fll） gene was identified by polymerase chain reaction-single-strand composi- tion polymorphism （PCR-SSCP） in 196 sheep among Small-tailed Han sheep, Tong sheep, Tan sheep and Oula sheep. Comparative sequence analysis of cloned products revealed an AGAC deletion at 294 bases up-stream of exon 7 of the TGF-βI gene （ site 14201 in gi76871756）. Statistical results of the genotype and allele frequencies in different breeds showed that gen- otype AB was dominant in the Small-tailed Han sheep. Genotype BB, however, was in majority in low- fecundity sheep. The results of a Chi-square test indi- cated that all the populations were in Hardy-Weinberg equilibrium.
文摘After 1500 male and female broiler chickens from a pure line were selected on the basis of plasma very low density lipoprotein (VLDL) concentration at 8 weeks of age,abdominal fat(AF),liver fat,body weight,meat traits and plasma lipids were determined,and effects of interaction between genotype and nutrition on AF and its correlated traits were studied.1) It was efficient to select against AF on the basis of plasma VLDL concentration.The indirect response of gizzard fat was the greatest,and that of liver fat was the second.AF was decreased,whereas liver fat was increased,feed conversion efficiency during growing period were improved, body weight and meat traits were both not influenced by selecting for low plasma VLDL concentration.2) Nutrition had significant effect on fat deposition and growth performance.Interaction between line and diet had evident effect on AF and its correlated traits.In general,diet had greater effect on H-VLDL line than L-VLDL line,namely chickens of L-VLDL line were less sensitive to diet than those of H-VLDL line.3) Due to high coefficients of variation of plasma VLDL and AF in H-VLDL and L-VLDL lines in the first generation.It will be possible that plasma VLDL is to be selected continuously to breed low fat line of broiler chickens of which the feed conversion efficiency is much better.Moreover,family combined with individual selection should be adopted during future generation selection and breeding because of significant family difference in plasma VLDL concentration.
文摘The reproductive performance and abdominal fat of the high VLDL (H-VLDL) and low VLDL (L-VLDL) lines were studied after divergent selection for plasma very low density lipoprotein (VLDL) concentration in broiler chickens at 8 weeks of age. It was shown that the main reproductive traits were higher in L-VLDL line than H-VLDL line. The beneficial correlated responses of the reproductive traits were produced by the selection for plasma VLDL. 1) Plasma VLDL concentration was significantly correlated with abdominal fat (r=0.50, P<0.01), ahich was higher than that with plasma triglyceride concentration. There was a significant difference in abdominal fat between both lines but age increase or food restriction may decrease this difference. The H-VLDL line had about twice as much abdominal fat as had L-VLDL at 8 weeks of age, while its mean body weight was similar to that of the L-VLDL line from birtl to the end of laying. 2) Mortality from apparently stress-related causes by food restriction for H-VLDL line females began to increase from 15 weeks of age and was 21% (38/180) higher compared with 13% (23/180) for L-VLDL line females. 3) Age of 5% Lying for L-VLDL line was 3 days less than that of H-VLDL line, age of 50% Lying was 37 days less for L-VLDL line than H-VLDL line, and the age of laying peak was similiar in both lines. Rate of lay at peak in L-VLDL and H-VLDL lines were 70.3%, 66.4%, respectively. 4) Fertility rate in L-VLDL line was significantly higher than that of H-VLDL line at 27 weeks of age (P=0.01) and there was a little difference in fertility rates between H-VLDL and L-VLDL line during late laying period. There were no significant differences between H-VLDL and L-VLDL lines in of day-old healthy the numbers chicks and hatchabilities of fertile and total eggs wheres mean numbers of healthy day-old chicks per hen were more is L-VLDL line than in H-VLDL line. 5) Under food restriction, egg production was higher in L-VLDL line than in H-VLDL line. It should be emphasized that the rate and amount of egg production in L-VLDL line were both significant higher than in H-VLDL line during early laying period (from 23 to 43 weeks of age, P<0.01). The mean egg production of LF line hens was ll eggs more than that of HF line ones throughtout the laying period (from 23 to 62 weeks of age). 6) Eggs in L-VLDL line were slightly heavier than those in H-VLDL line. Feed conversion (FC) ratio for L-VLDL line was lower than that in H-VLDL line betwen 23 and 62 weeks of age (5.01 and 5.46, respectively), especially FC ratio of L-VLDL line was significantly lower than that of HF line during 23 and 43 weeks of age (P<0.01). Also FC efficiency of breeding hens was higher in L-VLDL line than in H-VLDL line.
文摘Bovine fetal oviduct epithelial cells were transfected with constructed double marker selective vector(pCE-EGFP-IRES-Neo-dNdB) containing the enhanced green fluorescent protein (EGFP) and neomycin-resistant(Neo^r) genes by electroporation, and a transgenic cell line was obtained. Somatic cell nuclear transfer (SCNT) was cartied out using the transgenic cells as nuclei donor. A total of 424 SCNT embryos were reconstructed and 208 (49.1%) of them developed to blastocyst stage. 17 blastocysts on D 7 after reconstruction were transferred to 17 surrogate calves,and 5 (29.4%) recipients were found to be pregnant. Three of them maintained to term and delivered three cloned calves.PCR and Southern blot analysis confirmed the integration of transgene in all of the three cloned calves. In addition, expression of EGFP was detected in biopsy isolated from the transgenic cloned calves and fibroblasts derived from the biopsy. Our results suggest that transgenic calves could be efficiently produced by SCNT using transgenic cells as nuclei donor. Furthermore, all cloned animals could be ensured to be transgenic by efficiently pre-screening transgenic cells and SCNT embryos using the constructed double marker selective vector.
