In a bacteriological study of 412 samples of the udder secretion of sick cows with mastitis, 121 cultures of microorganisms of 15 species were isolated, which were represented in 54.9% of cases by gram-positive cocci, the remaining 45.1% by representatives of the Enterobacteriaceae and Ps. aeruginosa, staphylococci prevailed - 28.6%, streptococci - 22.6%, enterococci - 19.2%. When the incidence of cows with mastitis is more than 30%, the microflora was isolated from 81.8% of udder secretion samples, including pathogenic microflora (Staph. aureus, E. coli) - in 32.7% of cases, conditionally pathogenic (C. diversus, Ent. faecalis) - 23.6% and 20.0% - saprophytic microflora (Staph. saprophyticus, Staph. epidermidis, Ent. aerogenes, Ps. aeruginosa) and fungi (Сandida) - 5.5%. The results of the study showed that in clinically healthy lactating cows, the bactericidal activity of the udder skin varies depending on the functional state of the mammary gland and has a maximum value of 91.8 ± 2.0% in the first week after birth, decreasing to 87.8 ± 2 by the middle of lactation. .4% and becomes minimal during the launch period - 79.7±2.3%. The change in the bactericidal activity of the skin of the udder teats is associated with the state of other non-specific factors of local protection, in particular, the titer of lysozyme M and the level of somatic cells.

t has been established that the development of purulent-catharal inflammation of the former gravid horn of the uterus in cows after delivery as a result of abortion, dystocia, stillbirth, caesarean section, uterine dislocation or seedlings is accompanied by an increased microbial and fungal background of the uterus, in their symbiotic relationships. In cows without delivery during childbirth, only from the 5... 9th day after calving in 35.37% cows, the genitals were contaminated with various non-pathogenic microflora. In cows given maternity care, already on the 3rd day after calving, bacteria were isolated, which in 74.5% of cases were contaminated with pathogenic microflora S. aureus in 15.5% of cases, E. coli in 37%, K. pneumonia - 12% and S. pyogenes in 10% of cases. The results of mycological studies revealed that A. fumigatus, C. albicans and C. crusei were isolated from cows as a result of childbirth. It was found that in cows with purulent-catharal inflammation of the uterus in the milk of sick cows, a significant change, with a high degree of correlation, is: the content of somatic cells (CK) r = 0.63, lactoperoxidase (LPO) r = 0.65 and lactoferin (LF) r = 0.66. Milk obtained from patients with purulent-catharal inflammation of the former gravid horn of the uterus showed 2 times the total bacterial insemination than milk obtained from clinically healthy animals. At the same time it has a reduced number of lactic acid organisms after the first days of storage. Acid formation occurs faster by 5.0-15.0% than in control samples of milk prepared to produce lactic acid products. Acidity in Lactobacillus bulgarus-fermented milk was 12.0-13.3% higher than in starter control samples, and the viability of symbiotic coupling cells was an order of magnitude lower (2.5x106 vs. 2.5x107) compared to lactic acid control samples.