[ Objective] The aim of this research was to provide a theoretical basis for the.breeding and identification of multiparous Small Tail Han sheep. [ Method] The polymorphisms of serum esterase (Es) locus in Small Tai...[ Objective] The aim of this research was to provide a theoretical basis for the.breeding and identification of multiparous Small Tail Han sheep. [ Method] The polymorphisms of serum esterase (Es) locus in Small Tail Han sheep were detected by vertical discontinuous polyacrylamide gel electrophoresis (PAGE). According to the statistical analysis of different genotypes and their litter size, the correlation between Es polymor- phisms and litter size was analyzed. [ Result] There were three genotypes in Es locus, and Es^+- was the dominate genotype. The differences of ewe litter size in the 1 ,t parity among these three genotypes were nonsignificant ( P 〉 0.05), As far as the 2^nd and 3rd parity was considered, the litter size of genotype Es++ was significantly (P〈0.05) higher than that of Es-- and Es^+- ; the average litter size of Es++ was extremely significant ( P 〈 0.01 ) higher than that of Es - - and Es + - while there was no significant difference ( P 〉 0.05) between the latter two. [ Conclusion] The Es lo- cus could be regarded as a genetic marker locus for early selection of high-yielding ewes and Es ++ is the high-yielding genotype of Small Tail Han sheep.展开更多
The relationship between different BMPRIB genotypes of Small Tail Han sheep and FSHR and LHR mRNA levels during the oestrum was studied using semiquantitative PCR. The results indicated that FSHR mRNA extracted from t...The relationship between different BMPRIB genotypes of Small Tail Han sheep and FSHR and LHR mRNA levels during the oestrum was studied using semiquantitative PCR. The results indicated that FSHR mRNA extracted from the right ovary of BB (1.14±0.11) ewes showed higher levels compared with AA (0.44±0.11) and AB (0.36±0.08) ewes (P〈0.01), and LHR mRNA extracted from the right ovary of BB (0.42±0.02) ewes showed significantly higher levels compared with AA (0.23±0.02) and AB (0.25±0.04) ewes (P〈0.01); however, the mRNA extracted from the left ovary showed no significant difference in levels among the genotypes during the oestrum. It indicated that the fecundity induced by a mutation of BMPRIB in Small Tail Han sheep may be related to the changes of the mRNA expression of LHR and FSHR in ovary.展开更多
[ Objective] To open an exit for breeding high-fecundity Small Tail Han sheep according to genotypes. [ Method] By the PCR-RFLP, the polymorphism of ovine BMPR-IB gene was detected in Small Tail Han sheep of basic pop...[ Objective] To open an exit for breeding high-fecundity Small Tail Han sheep according to genotypes. [ Method] By the PCR-RFLP, the polymorphism of ovine BMPR-IB gene was detected in Small Tail Han sheep of basic population and breeding population. And its relationship with litter size was analyzed. [ Result] In the basic population, the frequencies of B + and BB genotypes were 77.78% and 14.81%, respectively, and their litter size per parity was 1.77 and 2.40, respectively. In the breeding population, the frequencies of B + and BB genotypes were 51.79% and 40.18%, respectively, and their litter size per parity was 2.54 and 3.02, respectively. [ Conclusion] The ovine BMPR-IB gene can be used as a molecular Qenetic marker for fecundity traits to establish high-fecundity Small Tail Han sheep.展开更多
Using the method of "random sampling in typical colonies of the central area of the habitat" and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Ha...Using the method of "random sampling in typical colonies of the central area of the habitat" and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Han sheep and 73 Tan sheep were examined and compared with those of 14 other sheep populations in China and other countries to investigate their levels of genetic differentiation. The average heterozygosities of Small-Tailed Han sheep and Tan sheep were 0.2360 and 0.2587, respectively. The average polymorphic information content values were 0.1974 and 0.2102, respectively. The average effective numbers of alleles were 1.5723 and 1.5751, respectively. The coefficients of gene differentiation in the four groups (including 4, 6, 13, and 16 sheep populations, respectively) were 0.049323, 0.059987, 0.1728, and 0.201256, respectively, indicating that the degree of gene differentiation at the structural loci was the least in Hu sheep, Tong sheep, Small-Tailed Hart sheep, and Tan sheep; followed by the above-mentioned four sheep populations and two Mongolian sheep populations; and was the highest in sheep populations belonging to the Mongolian sheep group, South Asian sheep, and European sheep. The earlier researchers' conclusions that both Small-Tailed Han sheep and Tan sheep evolved from Mongolian sheep were further verified by the results of this study. Hu sheep, Tong sheep, Small-Tailed Han sheep, and Tan sheep were decreasingly affected by the bloodline of Mongolian sheep to different degrees. The relationships among sheep populations were not closely related to the geographical distances among sheep populations.展开更多
[ Objective] To detect the polymorphism of BMPR-IB gene and analyze the relevance between genotype frequency of FecB gene and litter size. [Method] Mutation sites in the BMPR-IB gene of Small Tail Hart sheep were anal...[ Objective] To detect the polymorphism of BMPR-IB gene and analyze the relevance between genotype frequency of FecB gene and litter size. [Method] Mutation sites in the BMPR-IB gene of Small Tail Hart sheep were analyzed by PCR-RFLP. [ Resluts] The percentages of individuals with BB, B + and + + genotypes were 24.69%, 54.89% and 20.42%, respectively, and their average litter size per parity was 3.01,2.81 and 2.16, respectively. E Conclusion] The BMPR-IB gene can be used as a molecular genetic marker in fecundity traits. The FecB gene can effectively increase litter size of the Small Tail Han sheep and has additive action on litter size.展开更多
In this study fat-tail weight was estimated by external fat-tail dimensions. External fat-tail dimensions included upper, middle and lower width, length, length of gap, depth, upper and middle circumference recorded o...In this study fat-tail weight was estimated by external fat-tail dimensions. External fat-tail dimensions included upper, middle and lower width, length, length of gap, depth, upper and middle circumference recorded on 1,482 head of Lori-Bakhtiari lambs at 6 months. Of these about 311 lambs were slaughtered at the age of six months. Prediction equations were derived for fat-tail weight by multiple regression analyses with two methods. The results showed that the measure of middle circumference fat-tail was as most important measure in estimation of fat-tail weight. The measure of middle circumference fat-tail accounted for 76 percent of variation in fat-tail weight. The regression equations for predicting fat-tail weight using external fat-tail dimensions obtained from stepwise regression procedure can be estimated only with using from the lower width, length, middle circumference fat-tail and body weight with high acc, uracy (0.92). Average of fat-tail weight estimated in the age of six months in lambs was 2.39 kg. The highest regression coefficient of external fat-tail dimensions on fat-tail weight observed for the length of fat-tail (0.095 kg). Results of the present investigation showed that fat-tail weight in live sheep of Lori-Bakhtiari, could be estimated by measuring external fat-tail dimensions.展开更多
In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongoli...In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious.展开更多
The cDNA library of an ovary from Small Tail Han sheep before estrus was constructed by switching mechanism at 5' end of RNA transcript (SMART) approach. This library had a plaque titer of 1 x 109 pfu mL-1 and a 96...The cDNA library of an ovary from Small Tail Han sheep before estrus was constructed by switching mechanism at 5' end of RNA transcript (SMART) approach. This library had a plaque titer of 1 x 109 pfu mL-1 and a 96% recombinant ratio of which the fragment length of inserted average cDNA sequences was 1.0 kb. Based on bioinformatics analysis of the sequences, we obtained 338 expressed sequence tags (ESTs) from 380 cDNA clones which indicated 191 contigs. These contigs consist of 89 unmatched ESTs, 9 homologous known genes in sheep, and 93 homologous sequences in species of mouse, bovine, and human beings, including 19 sequences expressed in the ovary or follicle and 14 unknown sequences. Several candidate genes associated with sheep reproduction trait such as epidermal growth factor (EGF), estrogen receptor (ESR), Inhibin, follicle stimulating hormone receptor (FSHR), prostaglandin (PG), and transforming growth factor-β (TGF-β) were identified and the homologous were cloned from this library, which will contribute to compile expression profiles and find the major genes of prolificacy of Small Tail Han sheep.展开更多
文摘[ Objective] The aim of this research was to provide a theoretical basis for the.breeding and identification of multiparous Small Tail Han sheep. [ Method] The polymorphisms of serum esterase (Es) locus in Small Tail Han sheep were detected by vertical discontinuous polyacrylamide gel electrophoresis (PAGE). According to the statistical analysis of different genotypes and their litter size, the correlation between Es polymor- phisms and litter size was analyzed. [ Result] There were three genotypes in Es locus, and Es^+- was the dominate genotype. The differences of ewe litter size in the 1 ,t parity among these three genotypes were nonsignificant ( P 〉 0.05), As far as the 2^nd and 3rd parity was considered, the litter size of genotype Es++ was significantly (P〈0.05) higher than that of Es-- and Es^+- ; the average litter size of Es++ was extremely significant ( P 〈 0.01 ) higher than that of Es - - and Es + - while there was no significant difference ( P 〉 0.05) between the latter two. [ Conclusion] The Es lo- cus could be regarded as a genetic marker locus for early selection of high-yielding ewes and Es ++ is the high-yielding genotype of Small Tail Han sheep.
文摘The relationship between different BMPRIB genotypes of Small Tail Han sheep and FSHR and LHR mRNA levels during the oestrum was studied using semiquantitative PCR. The results indicated that FSHR mRNA extracted from the right ovary of BB (1.14±0.11) ewes showed higher levels compared with AA (0.44±0.11) and AB (0.36±0.08) ewes (P〈0.01), and LHR mRNA extracted from the right ovary of BB (0.42±0.02) ewes showed significantly higher levels compared with AA (0.23±0.02) and AB (0.25±0.04) ewes (P〈0.01); however, the mRNA extracted from the left ovary showed no significant difference in levels among the genotypes during the oestrum. It indicated that the fecundity induced by a mutation of BMPRIB in Small Tail Han sheep may be related to the changes of the mRNA expression of LHR and FSHR in ovary.
基金supported by Agricultural Stock Breeding Project of Shandong Province(Breeding of New Breeds of Excellent Local Mutton Sheep)
文摘[ Objective] To open an exit for breeding high-fecundity Small Tail Han sheep according to genotypes. [ Method] By the PCR-RFLP, the polymorphism of ovine BMPR-IB gene was detected in Small Tail Han sheep of basic population and breeding population. And its relationship with litter size was analyzed. [ Result] In the basic population, the frequencies of B + and BB genotypes were 77.78% and 14.81%, respectively, and their litter size per parity was 1.77 and 2.40, respectively. In the breeding population, the frequencies of B + and BB genotypes were 51.79% and 40.18%, respectively, and their litter size per parity was 2.54 and 3.02, respectively. [ Conclusion] The ovine BMPR-IB gene can be used as a molecular Qenetic marker for fecundity traits to establish high-fecundity Small Tail Han sheep.
基金This paper is translated from its Chinese version in Scientia Agricultura Sinica.We thank the anonymous reviewers for their comments on this manuscript.This study was supported by the International Cooperation Project of the National Natural Science Foundation of China(30310103007 and 30410103150)Project of the Basic Natural Science Foundation for Colleges and Universities in Jiangsu Province,China(06KJD230203).
文摘Using the method of "random sampling in typical colonies of the central area of the habitat" and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Han sheep and 73 Tan sheep were examined and compared with those of 14 other sheep populations in China and other countries to investigate their levels of genetic differentiation. The average heterozygosities of Small-Tailed Han sheep and Tan sheep were 0.2360 and 0.2587, respectively. The average polymorphic information content values were 0.1974 and 0.2102, respectively. The average effective numbers of alleles were 1.5723 and 1.5751, respectively. The coefficients of gene differentiation in the four groups (including 4, 6, 13, and 16 sheep populations, respectively) were 0.049323, 0.059987, 0.1728, and 0.201256, respectively, indicating that the degree of gene differentiation at the structural loci was the least in Hu sheep, Tong sheep, Small-Tailed Hart sheep, and Tan sheep; followed by the above-mentioned four sheep populations and two Mongolian sheep populations; and was the highest in sheep populations belonging to the Mongolian sheep group, South Asian sheep, and European sheep. The earlier researchers' conclusions that both Small-Tailed Han sheep and Tan sheep evolved from Mongolian sheep were further verified by the results of this study. Hu sheep, Tong sheep, Small-Tailed Han sheep, and Tan sheep were decreasingly affected by the bloodline of Mongolian sheep to different degrees. The relationships among sheep populations were not closely related to the geographical distances among sheep populations.
基金funded by the Agricultural Stock Breeding Project of Shandong Province (Breeding of New Breeds of Excellent Local Mutton Sheep)
文摘[ Objective] To detect the polymorphism of BMPR-IB gene and analyze the relevance between genotype frequency of FecB gene and litter size. [Method] Mutation sites in the BMPR-IB gene of Small Tail Hart sheep were analyzed by PCR-RFLP. [ Resluts] The percentages of individuals with BB, B + and + + genotypes were 24.69%, 54.89% and 20.42%, respectively, and their average litter size per parity was 3.01,2.81 and 2.16, respectively. E Conclusion] The BMPR-IB gene can be used as a molecular genetic marker in fecundity traits. The FecB gene can effectively increase litter size of the Small Tail Han sheep and has additive action on litter size.
文摘In this study fat-tail weight was estimated by external fat-tail dimensions. External fat-tail dimensions included upper, middle and lower width, length, length of gap, depth, upper and middle circumference recorded on 1,482 head of Lori-Bakhtiari lambs at 6 months. Of these about 311 lambs were slaughtered at the age of six months. Prediction equations were derived for fat-tail weight by multiple regression analyses with two methods. The results showed that the measure of middle circumference fat-tail was as most important measure in estimation of fat-tail weight. The measure of middle circumference fat-tail accounted for 76 percent of variation in fat-tail weight. The regression equations for predicting fat-tail weight using external fat-tail dimensions obtained from stepwise regression procedure can be estimated only with using from the lower width, length, middle circumference fat-tail and body weight with high acc, uracy (0.92). Average of fat-tail weight estimated in the age of six months in lambs was 2.39 kg. The highest regression coefficient of external fat-tail dimensions on fat-tail weight observed for the length of fat-tail (0.095 kg). Results of the present investigation showed that fat-tail weight in live sheep of Lori-Bakhtiari, could be estimated by measuring external fat-tail dimensions.
文摘In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious.
文摘The cDNA library of an ovary from Small Tail Han sheep before estrus was constructed by switching mechanism at 5' end of RNA transcript (SMART) approach. This library had a plaque titer of 1 x 109 pfu mL-1 and a 96% recombinant ratio of which the fragment length of inserted average cDNA sequences was 1.0 kb. Based on bioinformatics analysis of the sequences, we obtained 338 expressed sequence tags (ESTs) from 380 cDNA clones which indicated 191 contigs. These contigs consist of 89 unmatched ESTs, 9 homologous known genes in sheep, and 93 homologous sequences in species of mouse, bovine, and human beings, including 19 sequences expressed in the ovary or follicle and 14 unknown sequences. Several candidate genes associated with sheep reproduction trait such as epidermal growth factor (EGF), estrogen receptor (ESR), Inhibin, follicle stimulating hormone receptor (FSHR), prostaglandin (PG), and transforming growth factor-β (TGF-β) were identified and the homologous were cloned from this library, which will contribute to compile expression profiles and find the major genes of prolificacy of Small Tail Han sheep.