PSIX-11 Bacterial clinical mastitis associated with abortion in dairy cows

Abstract

Abstract Within the period from 20.04.2020 to 15.02.2021 the state of 2087 pregnant cows was studied to identify the connection between abortions and the occurrence of mastitis. During the study period 97 cases of clinical mastitis and 149 cases of abortion were identified. Abortions were observed in 42 out of 97 cows with registered clinical mastitis. It was found that cows that had a clinical form of mastitis during the first 45 days of pregnancy (in the embryonic period of development) subsequently had the maximum number of abortions - 27 heads or 64.28% of abortions of cows with mastitis. Among cows that had mastitis in the period of 46–150 days of pregnancy 13 cases of abortion were revealed (30.9% of abortions of cows with mastitis). Among cows that had mastitis during pregnancy for more than 150 days 2 cases of abortion were detected (4.7% of abortions of cows with mastitis). On the basis of bacteriological analysis, Staphylococcus spp., Streptococcus spp. and Enterobacteriaceae were isolated from milk of 15 aborted cows with the diagnosis of clinical mastitis. To identify species the conventional biochemical methods were applied together with the API 20 E, API Staph, API 20 Strep test (bioMerieux SA, France). In total, 18 species of pathogens were identified, including Ps. aeruginosa (n = 5), E. coli (n = 4), S. aureus (n = 1), S. saprophyticus (n = 8). Ps. aeruginosa, E. coli, S. aureus were isolated both from the organs of the reproductive system and from the milk of the cows who had had abortions after suffering from mastitis, whereas no relationship was found between the microflora of the reproductive system and the udder of the cows whose abortions are not associated with mastitis. The study was supported by the Russian Science Foundation, project No.20-16-00106