Abstract: Nuclear factor-κB (NF-κB) has close association with inflammation,immune response,differentiation and apoptosis.In the NF-κB passway,TLRs play an important role in the process of inflammatioin and immune response through the function of pathogen recognition and signal transduction.Underlying our previous investigations on the subclinical cow mastitis between Xinjiang brown cattle and Chinese Holstein and correlation of TLR4 E3+2021 genotype with subclinical mastitis,we measured the transcriptional level of nine major genes(NFκB1,NFκB2,RelA,c-Rel,RelB,IKKα,IKKβ,IKKγ,IκBα) of the NF-κB passway among three genotyping groups of AA,AB and BB.The results showed that the transcriptional level of NFκB1 and IKKα were significantly different(P＜0.05) and RelA, RelB,IKKβ, IKKγ and IκBα were extremely significantly different(P＜0.01) between Chinese Holstein and Xinjiang brown cattle in the BB genotype. The transcriptional level of IκBα were significantly different(P＜0.05) between two breeds in AB genotype. In the studies on Xinjiang brown cattle,we observed that the transcripts of AB genotype of RelB, IKKγ and IκBα were significantly higher than those of BB genotype(P＜0.05). While the transcriptional levels of the nine genes between AB and BB genotype were no significantly different in Chinese Holstein.Taken together,the variation of the mRNA transcriptional levels of NFκB1,RelA,IKKβ,IKKγ and IκBα between Xinjiang brown cattle and Chinese Holstein was probably associated with the different mastitis incidence intwo breeds. Moreover the high transcriptional levels of RelB, IKKγ, IκBα may be one of the causal to the low SCS in AA genotype in Xinjiang brown battle.

Key words: Xinjiang brown battle; Holstein; nuclear factor-κB; genotype