Lp gene expression in crossbreed buffaloes healthy and with mastitis

Mastitis is the main disease that affects the dairy herds, it is characterized by the inflammatory response of the mammary gland to infectious agents by changing their physiology. The first obstacle faced by a pathogen to enter the udder is composed of the barrier formed by the ceiling sphincter and the keratin cap formed by keratinized epithelium. Once the microorganism has passed through the teat canal and reached the mammary cistern, soluble and cellular factors begin to act with the aim of controlling the infection. Gene expression studies are being made in various organisms in order to identifying and characterizing genes with economically important traits related to diseases resistance. The enzyme lactoperoxidase (LPO) acts as a natural defense mechanism. It was performed the quantification of LPO gene expression in the milk from healthy buffaloes and from buffaloes with mastitis, by the real-time quantitative PCR method (qRT-PCR) with the aim of better understanding the immune response mechanisms related with the resistance and susceptibility phenotypes to mastitis. It was performed a total RNA extraction with Trizol from milk somatic cell of ten animals diagnosed with mastitis and from milk somatic cell of ten animals without infection. Total RNA quality and quantification analyze were performed to ensure the integrity of the samples. Quantification of gene expression was carried out through the ?? Ct method. The GAPH, HPRT1, EEF1A1 and RPLP0 genes were selected in the literature and used as reference genes. The quantifications analyzes were performed with the Ct values obtained from each gene. The LPO gene was 2.4 times more expressed in animals with mastitis compared to animals without mastitis (p-value = 0.35), with no significant difference. This gene expresses a protein synthesized in the mammary gland by thiocyanate ions (SCN-) originated by hepatic metabolism and hydrogen peroxide (H₂O₂) arising from the activity of white blood cells and other cells to generate reactive products with strong antimicrobial activity. Mastitis is a multifactorial disease and affected by many genes, further researches with animals at different stages of infection and with others genes are necessary to understand the mechanism of immune response related to mastitis.