Immunological status of the blood of clinically healthy and lactating cows with mastitis

Abstract

Mastitis in high yielding lactating cows is the most common disease that causes enormous economic damage to livestock farms. According to leading scientists, when studying the problem of mastitis, the greatest interest is in studying the dynamics of changes in the immunological blood indicators of cows during the occurrence and development of the inflammatory process in the udder. To conduct research, three groups of lactating Holstein cows of 2–3 lactations with an annual milk production of 7356–8000 kg of milk, belonging to one of the farms in Voronezh region, were formed. The first group (n=8) included clinically healthy animals, the second (n=8) - cows with subclinical mastitis, the third (n=8) - cows with clinically pronounced catarrhal mastitis. Blood samples were taken from all animals to determine immunobiochemical and molecular genetic indicators. The studies have established that the level of expression of the genes for the pro- and anti-inflammatory cytokines IL-10 and IL-4 was by 2.6 and 1.5 times lower, respectively, in the cows with subclinical mastitis and by 5.8 and 3.9 times lower in the cows with clinically pronounced catarrhal mastitis, respectively, in comparison with clinically healthy animals. At the same time, the expression of pro-inflammatory INF-γ was by 7.6 and 14.8 times higher in the cows with subclinical and catarrhal mastitis, respectively, compared to clinically healthy animals.