Abstract:

【Objective】 The objective of the paper was to investigate different mammary membrane proteins between clinical healthy dairy cows and dairy cows with mastitis, and to further for exploring the mechanism of pathogenesis. 【Method】 This study presented the membrane protein changes of mammary gland from clinical healthy dairy cows and dairy cows with mastitis, using two-dimensional gel electrophoresis (2-DE). After the protein stained with Coomassie Blue G-250, twelve differential expression protein spots were detected by PDQuest 7.4 software and then subjected to the HPLC coupled with ion trap mass spectrometer system. Proteins were identified using the SEQUEST software to search the NCBInr database, and mRNA level of differential expression protein was presented by semi-quantity RT-PCR. 【Result】 Eleven proteins were identified. Three proteins were down-regulated and eight proteins were up-regulated in cows infected with clinical mastitis, they were involved in signal transduction, binding and transport activity. The mRNA level of calgranulin B expression in mammary gland of cows with clinical masitis was 1.6-fold higher than the healthy dairy cows confirmed by semi-quantity RT-PCR protocol. 【Conclusion】 The results may provide valuable information for the investigation of the host mammary immune system responses to defense against pathogens at the protein level and potential protein targets for treatment.

Key words: dairy cows, clinical mastitis, membrane protein, proteome