Polymorphism Of Microsatellite Markers And MHC And Their Relationships With Growth Traits In Lu-xi Cattle

Microsatellite markers are currently recognized genetic diversity studies, reveal and implementation of economic traits most commonly used marker-assisted selection of molecular markers. Currently, the application of microsatellite markers in the study of Chinese yellow cattle and dairy cattle genetic diversity has been a lot of research work carried out, but the research report of Lu-xi cattle is still rare.8 pairs of polymorphic microsatellite out of 30 microsatellite loci in Luxi cattle chromosome were selected from GenBank. Genetic diversity of Lu-xi cattle and the relating effects between genotypes and growth traits were analyzed in 120 individuals by using least squares linear model and DNA analysis technique. The results indicated that, eight microsatellite loci had significant effect on some growth traits of Lu-xi cattle (P<0.05 or P<0.01). The results are summarized as:(1)The genetic polymorphism of Lu-xi cattle: A total of 34 alleles were detected. Each microsatellite loci in the number of alleles is ranging from 3-6, and the average number of alleles is 4.25. The average heterozygosity (H) is 0.5613: the polymorphism information content (PIC) is 0.4983.(2)The significant effect on some body size characteristics of Lu-xi cattle: The most favorable genotypes for interrelated traits are AE at ETH185 for height at withers, CC at BM711 and BB at BM1824 for body length, AD at TGLA53 and CC at BM711 for circumference of cannon bone, BB at BM1824 and AB at DVGA55 for abdominal girth respectively. While the disadvantages genotypes are AA at ETH185 height at withers, BC at ETH185 and EE at BM711 for circumference of cannon bone, AB at BM1824 for body length and abdominal girth, AA at DVGA55 for abdominal girth respectively.(3)The significant effect on body weight characteristics of Lu-xi cattle: The most favorable genotypes are AC at TGLA53, BD at ETH185, AB at BM711, AC at DVGA46 and BB at DVGA44 and DVGA55 for body weight. While the disadvantages genotypes are AD at DVGA46 and DVGA44, BC at ETH185, AA and AC at DVGA55, BB at TGLA53.(4)Investigate Lu-xi cattle genetic diversity of MHC genes and genetic variation: PCR-SSCP, sequencing techniques and the least square method to fit a linear model were used to explore the different MHC genotypes and growth traits Lu-xi cattle correlation. Lu-xi cattle MHC genetic diversity is in general, different genotypes on the growth characteristics of Lu-xi cattle had significant effect (P<0.05). The correlation analysis of three genotypes and growth traits about the BoLA-DRB3 * exon2 gene showed that: In addition to height and circumference of two traits, but in the other 4 traits were found on a significant growth of Luxi cattle trait loci and alleles. Traits in body length, AA genotype was significantly higher than AB-type (P <0.01), that AA genotype may be beneficial to the growth of cattle. In the chest, abdominal circumference and body weight on 3 characters, AA genotype was significantly higher than AB and BB-type type (P <0.01), that AA-beneficial growth and development of cattle. On the growth rate significantly affected the most favorable genotype is AA, following by the BB type.The length of BoLA-DRB3 * exon 2 sequence of the target gene of the original is 168bp, In length 168bp that found by sequencing a total of mutations is14, a common mutation is11. BoLA-DRB3 * exon 2 gene in the 3 genotypes are AA, AB and BB, AA-type base in the first 55 T mutation at the A, AB-type is in the first 56 bases at the C mutation G, BB Type in the first G mutation at nucleotide 153 A.The results make it useful for Lu-xi cattle breeding selection and the early selection of guiding.