author(s)
R Lakshmi, KK Jayavardhanan and J Thanislass

abstract
The present study evaluated the expression of TLR2 in milk somatic cells bovine mammary glands infected with Staphylococcus aureus. The research work was carried out in college of Veterinary and Animal Science, Mannuthy, Kerala, during April 2015 to December 2015. Milk samples were screened for subclinical and clinical mastitis caused by S. aureus. For the expression assay, total RNA from milk somatic cells was isolated and converted as cDNA using oligo (dT) primers. Relative expression of mRNA of TLR2 gene was analysed using Illumina Eco® RT-qPCR system. Analysis of variance revealed significant difference (P ≤ 0.01) for expression of TLR2 gene in subclinical and clinical mastitis caused by S. aureus. The relative expression of TLR2 gene varied from 7.04 to 8.87 fold increase in sub-clinical mastitis cases caused by S. aures with a mean of 7.89 fold, as compared to normal. In case of clinical mastitis, relative expression varied between 1.67 to 3.58 with a mean of 2.28 fold, when compared with healthy (normal) cows.The relative expression of TLR2 was highly significant (P ≤ 0.01) in sub-clinical affected cattle compared with clinically affected cattle. The expression of TLR2 gene at high level in subclinical mastitis might assist to subside itself without precipitating into clinical mastitis. Therefore, TLR2 might consider as candidate gene to screen for mastitis resistance in cattle population. and S. aureus.