FecB基因对杜×寒杂交肉羊产羔数及羔羊生长发育的影响

利用绵羊多胎基因FecB分子检测技术,检测分析杜×寒杂交肉羊基因型及对产羔数和羔羊生长发育的影响。结果表明：在杜×寒杂交F1、F2和F3代类群中,存在BB、B＋和＋＋三种基因型,并以B＋基因型为主。杜×寒F1代母羊B＋基因型频率极显著高于杜×寒F2、F3代母羊（P〈0.01）,F2代母羊B＋基因型频率显著高于F3代母羊（P〈0.05）。杜×寒F1、F2、F3代B＋基因型繁殖母羊产羔数比同代＋＋基因型母羊分别增加0.54、0.65和0.66只（P〈0.01）。杜×寒F1代繁殖母羊平均产羔数（1.67只）显著高于杜×寒F3代（P〈0.05）,比F2代平均产羔数增加0.28只（P〉0.05）。B＋基因型母羔初生体重、体尺和3月龄断奶体重极显著小于＋＋基因型母羔（P〈0.01）,B＋基因型公羔初生及3月龄断奶体重、体尺都小于＋＋基因型公羔（P〉0.05）,表明FecB基因不仅是影响杜×寒杂交肉羊产羔数的主效基因,而且在一定时期内也影响羔羊的生长发育。

Effect of FecB Gene on Litter Size and Lamb Growth and Development of Dorper × Han Crossbred Sheep

The molecular detection technique for sheep fecundity gene(FecB) was used to analyze the genotype of Dorper×Han crossbred sheep and its effect on litter size and lamb growth and development.The results showed that there were three genotypes,BB,B+ and ++ in Dorper × Han F1,F2 and F3 populations,and B+ genotype was the major.The B+ genotype frequency of F1 ewes was very significantly higher than that of F2 and F3 ewes(P<0.01) and the B+ genotype frequency of F2 ewes was significantly higher than that of F3 ewes(P<0.05).The litter size of B+ genotype F1,F2 and F3 ewes were 0.54,0.65 and 0.66 more than that of the ++ genotype ewes(P <0.01) respectively.The average litter size of F1 ewes was 1.67,which was significantly higher than that of Dorper × Han F3 ewes(P <0.05) and was 0.28 more than the F2 ewes(P> 0.05).The bodyweight,body size at birth and bodyweight at weaning of B+ genotype ewe lamb were very significantly lower than those of ++ genotype(P <0.01),but for ram lamb,the differences were slightly(P> 0.05).Therefore,FecB gene not only was the major gene of litter size for Dorper × Han crossbred sheep but also affected the growth and development of the lambs in certain period.