Expression of L selectin molecule on peripheral leukocyte in response to nisin treatment during acute bovine mastitis

Abstract

Concentration of interleukin 8 (IL 8) in milk serum and blood leukocyte adhesion molecules were studied in healthy cows (group I) and during clinical mastitis with the treatment of Nisin and Vitamin E plus Selenium (group II) and Amoxicillin (group III). The somatic cell count (SCC) was higher in mastitic cows before treatment (P<0.05). However, the count decreased in both the treated groups as compared to pretreatment count (P<0.05). The proinflammatory cytokine i.e. interleukin 8 (IL 8) was higher in milk serum before treatment, but it decreased in both the treated groups on day 7 (P<0.05). The expression of L selectin on peripheral polymorphonuclear cells (PMNs) was lower in mastitic cows compared to healthy cows both before and after treatment (P<0.05). However, the mean fluorescent intensity (MFI) of L selectin enhanced significantly in group II cows on day 7 (P<0.05). The concentration of Selenium and Vitamin E was lower in mastilic cows. Serum Selenium concentration increased significantly in group II cows as compared to pretreatment values (P<0.05). The results indicate that Nisin and Vitamin E plus Selenium therapy enhances the expression of 1, selectin, which is related to enhancement of the mammary defense. Non antibiotic treatment along with Selenium and Vitamin E was effective in reduction of SCC and IL 8 from the inflamed udder compared to standard antibiotic treatment, Hence combination therapy of nisin and Selenium plus Vitamin E may be recommended for the treatment of mastitis in such farming systems where antibiotics are not allowed. Furthermore development of such combination therapy is important in reducing the antibiotic residue from the human food chain.