Somatic cell count and chemical composition of milk in naturally BLV-infected cows with different phenotypes of blood leukocyte acid phosphatase

Abstract. Effectiveness of the methods applied to control mastitis is low. Therefore, indices are sought which could improve cow immunity to udder pathogens. The aim of the study was to determine the relationship between the polymorphism of blood leukocyte acid phosphatase (AcP), BLV infection, the somatic cell counts and the milk composition in the first trimester of lactation. Studies were performed on a population of 65 Black-and-White cows, aged 3–6 years, from a leukemia-dominated herd. Enzootic bovine leukemia was diagnosed with ELISA and PCR tests. The following analyses were performed: the contents of total protein, lactose, dry matter, somatic cell count in milk as well as microbiological analyses.

The obtained results indicate the occurrence of an association between a natural BLV-infection and mammary gland secretion disturbances in cows, whereas the relationship with the acid phosphatase polymorphism is not explicit. The obtained results encourage the continuation of studies into the role of blood leukocytes AcP in the pathogenesis of mastitis.