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In this study, 265 Chinese Holstein cows (parity 82, second child 89 3 tire 94) for the study, research related to mastitis in dairy cows to promote osteoclast factor 1 (osteoclast stimulating factor 1 , OSTF1) gene and the α1-antitrypsin (α1-antitrypsin, α1-AT) genes, the bracket is attached the gene factor A (棚架 Attachment factor A, SAF-A, or Heterogeneous Nuclear ribonucleo protein of U, HNRPU), and disintegrin β2 (integrin relationship between Bata2, ITGB2) gene single-stranded nucleotide polymorphisms (single nucleotide polymorphisms, SNPs) and somatic cell score (somatic cell score, SCS), in order to find solutions that can improve the cows mastitis resistance genetic mark. PCR-SSCP and DNA sequencing of technical analysis OSTF1 gene single nucleotide polymorphism; using PCR-SSCP technique using PCR-RFLP and CRS-PCR and DNA sequencing results α1-AT gene outside 2,4 exon The polymorphism detection; using PCR-SSCP and DNA sequencing technology to detect the polymorphism of the gene sequences of 211 Holstein cows HNRPU; the ITGB2 gene polymorphism detection by PCR-RFLP technique. Using the method of least squares analysis of the association between the SNPs and SCS. To obtain the following results: 1. The amplified OSTF1 extragenic exon 7 region exists the A45416G and C45436T 2 mutation point, wherein A45416G mutation point lead to methionine (M) becomes a valine (V). The SSCP analysis AA, AB, BB, AC, CC 5 genotype frequencies were 0.515,0.366,0.075,0.035,0.009. Using the method of least squares analysis of the relationship between OSTF1 gene polymorphism in Holstein cows cell score (somatic cell score, SCS), results showed that the: polymorphic loci amplification products for P3 the BB genotype SCS least squares mean significantly lower than AA, AB, AC genotype corresponding value (all P lt; 0.05); between AA, AB, AC SCS least squares mean difference was not statistically significant (P gt; 0.05). For mastitis resistance, AA is the most unfavorable genotypes BB favorable genotype. The study results suggest that the B allele OSTF1 gene A45416G polymorphic loci are resistant to mastitis in dairy cows. 2.α1-AT gene exon 2 G5503A, G5746C two synonymous mutations. G5503A mutation sites detected by PCR-RFLP found three genotypes AA, AB and BB, frequencies were 0.3633,0.4644 and 0.1723. G5746C mutation sites CRS-RFLP testing found three genotypes CC, CD and DD, and their frequencies were 0.3483,0.4906 and 0.1611. Two polymorphic loci of the nine genotype combinations, AACC, AACD, AADD, ABCC, ABCD, ABDD, BBCC, BBCD and BBDD their frequencies were 0.2697,0.0899,0.0075,0.0749,0.3408, 0.0412,0.0037,0.0599 and 0.1124. Analysis of the relationship of the α1-AT gene polymorphism and Holstein cows SCS, using the least squares method The results show that: the BB genotype SCS least squares mean very significantly lower than AA and AB genotype (P lt; 0.01), AB significant lower than the AA genotype (P lt; 0.05); CC, CD, DD three genotypes SCS least squares mean difference was not significant. Genotype combination analysis showed BBDD genotype combinations SCS least squares mean significantly lower than the AACC and AACD genotype combination. For mastitis resistance, AA unfavorable genotypes, BB favorable genotype AACC and AACD unfavorable genotype combination, BBDD favorable genotype combination. α1-AT gene B allele and BBDD of combination of genotypes resistant to mastitis in dairy cows. 3. HNRPU Gene exon region exists C7277T mutation point. PCR products were SSCP analysis AA, AB, BB 3 genotype frequencies were 0.3507,0.4408 and 0.2085. Using the method of least squares analysis HNRPU gene polymorphism and somatic cell score of Holstein cows (somatic cell score, SCS), the results show that: AA, AB and BB genotypes SCS least squares mean differences were significant (P lt; 0.05), SCS least squares mean the relationship is BB lt; AB lt; AA. For mastitis resistance, three genotypes AA is the most unfavorable genotypes BB is the most favorable genotype. The study results suggest that the C7277T polymorphic loci gene HNRPU B alleles are resistant to mastitis in dairy cows. The 4. ITGB2 gene T18587C, G28301A two mutations detected. T18587C locus genotype frequency of AA, AB and BB were 0.3517,0.4788 and 0.1695, A and B gene frequencies were 0.5911 and 0.4089; G28301A locus CC, CD and DD genotype frequencies were 0.5678 0.3771 and 0.0551, C, and D of the gene frequency of 0.7564 and 0.2436, respectively. Two polymorphic loci of the genotype combinations, AACC, AACD, ABCC, ABCD, ABDD, BBCC, BBCD and BBDD their frequencies were 0.2881,0.0636,0.2585,0.1991,0.0212,0.0212, 0.1144, and 0.0339. The method of least squares analysis ITGB2 gene polymorphism and somatic cell score of Holstein cows relationship polymorphic loci for P5, SCS Least squares mean the relationship is BB lt; AB lt; AA, the difference between the three is not significant SCS least squares mean relationship; polymorphic loci for P15 DD lt; CD lt; CC three mutual differences were significant (P lt; 0.05). Mastitis resistance, CC is the most unfavorable genotypes DD favorable genotype. Genotype combination analysis showed that the the 8 genotype combinations SCS least squares mean difference was not significant (all P gt; 0.05). The study results suggest that the D allele ITGB2 gene G28301A polymorphic loci are resistant to mastitis in dairy cows. In summary, the Holstein cow mastitis gene polymorphism and somatic cell score analysis that OSTF1 B allele of the gene, α1-AT gene B allele and BBDD genotype combination , HNRPU gene B allele ITGB2 of gene D allele can serve to improve the the resistant genetic markers of mastitis in dairy cows.
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