DOI: 10.36871 / vet.san.hyg.ecol.202002020
УДК 619:618.19-002:636.22/28

Authors

Avduevskayа N.N. Vologda Branch of Federal State Budget Scientific Institution «Federal Scientific Center – K.I. Skryabin, Ya.R. Kovalenko All-Russian Research Institute of Experimental Veterinary Medicine, Russian Academy of Sciences», Vologda, Russian Federation

Abstract

As a result of microbiological studies of the udder secretion of lactating cows, conducted in ten livestock farms in the Vologda, Yaroslavl and Kostroma regions, XNUMX cultures of pathogenic and opportunistic microorganisms, as well as lactic acid and other non-pathogenic flora were isolated from XNUMX samples of the studied milk. At the same time, it was revealed that S. aureus occupies a leading place in the spectrum of the selected pathogenic microflora. In XNUMX, the species composition of the pathogenic microflora in the above-listed farms was represented by isolates of Staphylococcus aureus – in XNUMX% of cases, then Streptococcus Agalactiae– in XNUMX%, enterobacteria – in XNUMX% and opportunistic Staphylococcus – in XNUMX% of cases. S. aureus was allocated by us in seven farms out of ten, the percentage of its allocation ranged from XNUMX% to XNUMX%. At the same time, other pathogenic flora was isolated in the studied farms in smaller quantities. So opportunistic Staphylococcus was detected in three agricultural enterprises out of ten in XNUMX % – XNUMX% of cases, Streptococcus Agalactiae – in seven – from XNUMX% to XNUMX%, enterobacteria in five – from XNUMX% to XNUMX% of cases, respectively. When determining the sensitivity between isolates of S. aureus with other microorganisms in different concentrations by the method of "hole" in meat-peptone agar, the negative influence of Staphylococcus aureus on pathogenic (enterobacteria and Streptococcus Agalactiae), as well as lactic acid and the other non-pathogenic microflora was revealed. This fact indicates that in the conditions of intermicrobial relations, Staphylococcus aureus has the ability to have an antagonistic effect on the listed flora. The article was completed in accordance with state assignment №XNUMX-XNUMX-XNUMX.

Keywords

mastitis of cows, Staphylococcus aureus, Streptococcus Agalactiae, antagonistic activity, the zone of growth inhibition.