The Role of Neutrophil on Subclinical Mastitis in Cows

Mykola Zhelavskyi

Abstract

It has been reported that the neutrophils are actively involved in the local udder immune defense. The aim of this study was to investigate the role of milk neutrophils in subclinical mastitis in cows. The research carried out on 70 cows at the farms of the Khmelnitsky Region Ukraine. Cows were divided into experimental (n = 37) and control (n = 33) groups. The indicators of
the cytochemical reactivity of oxygen-independent and oxygen-dependent factors of protection on milk phagocytes, cell migration activity index and correlation were evaluated. The results were expressed as mean ± SD and percentage. Changes in the composition of cells were observed: increase of neutrophils (P < 0.01), monocytes (P < 0.01), and lymphocytes (P < 0.05). The indicators like cationic proteins (CP), myeloperoxidase (MPO), reaction neutrophils with nitro-blue tetrazolium (NBT), activation of neutrophils index (ANI) and cytological index (CLI) differed significantly in subclinical mastitis in cows in relation to healthy control group. The neutrophils activation occurred by initiation of respiratory burst, which triggered apoptosis induced by antimicrobial activity. Alterations on the cells migration activity index were observed in subclinical mastitis in cows. Based on results we can suggest that determination of the parameters related to milk neutrophils and the behavior of cell migration could contribute more information to subclinical mastitis diagnosis.