Abstract:

To detect the DNA variation of bovine TLR4 gene, a 321bp segment of TLR4 gene exon m was analyzed by PCR-RFLP. The resuhs showed that a mutation exists in the amplified product, which can be recognized by restriction endonuclease Bbv12 1 and induced that changed Thr into Ile. Both allele C and T were found in the population and this was a moderate polymovphism, but C was dominant allele. In addition, the correlation of the genotype and dailry mastitis was also analyzed in this experiment by the least square analysis. The resuhs showed that the SCS of different genotypes had the trend of CC 〉 CT 〉TT. But statistical results indicated that SCS was not significantly affected by different genotypes （ P 〉 0.05 ）.

Key words: TLR4 gene , PCR-RFLP , SCS , mastitis

摘要：

采用PCR-RFLP技术，对奶牛TLR4基因外显子Ⅲ321bp的部分序列进行多态性分析，结果发现扩增产物C到T突变处存在限制性内切酶Bbv12Ⅰ酶切位点，并且导致编码氨基酸由苏氨酸变为异亮氨酸。C、T等位基因在牛群中均有分布并且属于中度多态，C等位基因占优势。利用最小二乘拟合线性模型将基因型效应与奶牛乳房炎易感性进行关联分析，结果表明不同基因型奶牛的体细胞评分（SCS）表现出CC基因型〉CT基因型〉TT基因型的趋势，但运用SAS9．0软件统计不同基因型对体细胞评分的最小二乘均值没有显著性差异（P〉0．05）。

关键词: TLR4基因 PCR-RFLP 体细胞评分 乳房炎