Polymorphism Analysis Of Sow ESR And RYR1 In Heilongjiang Scale Pig Farms

Among the numerous quantitative traits among sows, litter size is a relatively low heritability traits,it is only about 0.1. The growth and reproductive rates of pigs in China are below international levels, it is difficult to greatly improve production traits and reproductive traits by conventional breeding methods. The use of molecular marker-assisted selection can greatly shorten the breeding time and improve breeding efficiency. ESR gene is one of the major genes influence the litter size, and with a number of other economically important traits in pigs and there is no obvious significant negative correlation. RYR1 gene is a major gene on meat quality traits, scholars carried out extensive research on RYR1 gene and found that RYR1 gene is affected in mutation on pig growth, reproduction and other properties, where the harmful effects of RYR1 gene can lead to sow conception rate,embryo survival rate, and may even affect the piglet viability.In this study, we collected Min pig(683) and Large White(224) total 907 sows in more than600 medium-sized in 5 farms in Heilongjiang Province,ESR and RYR1 gene polymorphism testing, main research results are as follows:(1)Among the 703 Min pigs, the frequencies of ESR genotype AA, AB and BB were 0.5320,0.3969 and 0.0711, the frequencies of that allele A and B were 0.7305 and 0.2695; Among the 224 Yorkshire samples the frequencies of ESR genotype AA, AB and BB were 0.6025,0.3320 and 0.0655.That allele A and B were 0.7685 and 0.2315. ESR gene, BB genotype is recognized as the dominant genotype, allele B is dominant allele, corresponding to a higher number of calving. The frequencies of allele B and genotype BB in Min pig and Yorkshire is difference compared with previous reports, the advantage of allele B in Min pig was reduced in recent years may be that the breeding work of ESR gene in Large White has achieved significant results.(2)The frequencies of RYR1 genotype NN, Nn and nn in Min pig were 0.8421, 0.1565 and0.0014, the frequencies of allele N and n were 0.9204 and 0.0796;the frequencies of RYR1 genotype NN,Nn, nn in Large White were 0.7664, 0.2254 and 0.0082. The frequencies of allele N and n were 0.8791 and 0.1209. In this experiment,compared the results before allele n in RYR1 gene was dropped significantly, probably because Heilongjiang Province has stepped up efforts in Min pig breeding in recent years. The effect of the excluding work of allele n in Min pig was significant; compared with earlier studies the frequency of allele n in large White is 0.1209, the frequency of obviously n was obviously increased, and the excluding work of allele n in Great White should be further strengthened.