Pathogens transmission and cytological composition of cow’s milk

The article deals with the data on the quantitative and species composition of somatic cells in milk of cows of Black spotted breed. In the main period of lactation, the number of somatic cells in milk is up to 100 ths/cm 3 . In cases of subclinical mastitis, the somatic cell count in the udder secretion increases to 30-35 mL/cm 3 . However, it should be noted that in the case of subclinical mastitis their number increases in thousands times. Thus, studying the species composition of somatic cells and morphological structure of basophils in milk of cows with subclinical mastitis, we did not find any relationship between their number, morphological structure and period of disease. Results of our study show that pathogenic staphylococci (Staphylococcus aureus) were the cause of subclinical mastitis in 67-73% of cases. Streptococcus agalactiae caused the disease in about 20% of all cases. The results of the study of bacterial contamination of the udder skin showed that regardless of the animal age, pathogens of subclinical mastitis are always present on the udder skin. The main carrier of the subclinical mastitis pathogens from the sick animal to the healthy one is the rubber of milking cups.