Polymorphysm Of Microsatellite DNA Markers Crossbreed From Poll Dorset And Small-tailed Han Sheep

The proportion of crossbreed sheep in mutton production in northwest region becomes more and more, in order to offer instructor for mutton production, we research its genetic markers. Development law of filial-generation (Poll Dorset×Small-tailed Han sheep), genetic diversity of microsatellite locus and correlation between microsatellite locus and early growth traits of filial-generation were investigated. The results as follows:(1) Gompertz model was better in fitting the growth curve of filinal-generation (Poll Dorset×Small-tailed Han sheep) between the two models (Logistic, Gompertz), the R~2 was 0.9960. Meanwhile, the parameters of growth model were obtained. The maximum body weight was 25.87kg for bucks and 22.64kg for does, maximum month weight was 4.229kg for bucks and 3.681kg for does, spinodal age was 1.98 months for bucks and 2.43 months for does, spinodal weight was 12.94kg for bucks and 11.32kg for does, constant growth rate was 44.35% for bucks and 44.11% for does, respectively.The results indicated that it was affected significantly by sex for growth, but it was not notable. About growth rate, the bucks were much faster than does.(2) The polymorphism of five microsatellite loci was analyzed for six populations about 220 sheep. The results showed that the number of alleles for each microsatellite locus ranged from 11 to 19, and the length of them ranged from 87 to 215bp.The heterozygosity (H) and polymorphic information content (PIC) of five microsatellite loci were 0.7598~0.9253 and 0.6800~0.9206, the average were 0.8798 and 0.8448, respectively, with the highest and the smallest loci of BM2133 and ILSTS004, respectively, and all of them were higher than 0.5. It indicated that five microsatellite loci we chose were high polymorphic markers and can be effectively used to analyze the genetic diversity of sheep.(3) 50 Filinal-generation (Poll Dorset×Small-tailed Han sheep) were used to analyze the correlation between five microsatellites and early growth traits. The results showed that CSSM66 and BM2133 affected body length and body high at birth (P<0.01), and ILSTS004 also had influence (P<0.05) on body weight at birth.