Study On Microsatellite Marker Of Hybridization Combination Of Poll Dorset, Tan Sheep And Small-tails Han For New Population Of Mutton Sheep In Northwest Of China

The genetic structure, genetic variation, growth and development traits of maleparent, Female parent and two crossbreeds on hybridization combination of PollDorset,Tan sheep and Small-tails Han for new population of Mutton sheep inNorthwest of China were studied using 7 microsatellite DNA markers, The geneticlinkage between microsatellite loci and birth weight, weaning weight, body weight,body height, trunk length were analyzed with 4 microsatellite loci (MCM38,BMS1561, ILSTS0054, OY5 on the eighteenth chromosome of sheep) by singlemarker method. The results were as follows:1. The results showed that 7 microsatellite loci could be amplified successfullyand 116 alleles were found, other population were not at Hardy-Weinberg equilibriumat 7 locus,except that the population of Poll dorset was at Hardy-Weinbergequilibrium at most of locus by Hardy-Weinberg test, which indicated that the selectedlocus could analyze genetic variation between population effectually. The meanpolymorphism information content value was between 0.7077～0.8396, The meanheterozygosity was between 0.7454～0.8665, The average effectivenumber of alleleswas between 6.8949～7.9321,Which indicated that the 5 breeds had abundant geneticdiversity and the genetic variation was analyzed effectually.2. The heterosis between Poll Dorset and others was predicted by comparing thegenetic distance. The most distant relationship based on the Ds genetic distanceamong them is Poll Dorset and TH, the follows is Poll Dorset and Small-tails Han,Poll Dorset and Tan Sheep. The most distant relationship based on the Da geneticdistance among them is Poll Dorset and TH (the crossbreed of Tan sheep andSmall-tails Han, TH), the follows is Poll Dorset and Tan Sheep, Poll Dorset andSmall-tails Han. So Poll Dorset had the most distant relationship with TH and theheterosis between Poll Dorset and TH is the largest.which indicated that it wasFeasibility and ideality of hybridization combination that Poll Dorset was used asmale parent and the Offspring Hybridized between Tan sheep and Small-tail Han wasselected as Female parent.3. BMS1561 and MCM38 have no significant affects on these traits of birthweight, weaning weight, body weight, body height and trunk length (P＞0.05).4. The results on genetic linkage showed that ILSTS0054 affects birth weight and body weight of TH significantly (P＜0.01), OY5 affects trunk length of THsignificantly (P＜0.01), and the same as OY5 affects body weight and trunk length ofTTH (the crossbreed of Poll Dorset and TH) (P＜0.05).5. The body weight of sheep with genotype 151135 in ILSTS0054 is significantlyhigher than that with genotype 151131, 155137, 157137(P＜0.05). The trunk length ofsheep with 145137 genotype in OY5 is significantly higher than that with genotype147137(P＜0.05).So it be deduced that there probably is an area that affects bodyweight and trunk length of New Population of Mutton Sheep in Northwest of Chinarespectively near ILSTS0054 and OY5, ILSTS0054 and OY5 maybe become linkagemarkers of these traits. But the numbers of microsatellite loci and samples are limited,if ILSTS0054 and OY5 are regarded as linkage markers of these traits and are used tobreed by molecular marker mssistant and election, we need more researches.Key word: Sheep, Microsatellite, Genetic diversity, Nei genetic distance, Geneticlinkage...