DOI: 10.36871 / vet.san.hyg.ecol.202102010
УДК 619:618.19-002:636.22/28
Authors
Avduevskyа 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
Over the past two years (2019, 2020), we have studied 660 milk samples from
cows with various forms of mastitis, delivered from 50 dairy farms and complexes.
At the same time, 1240 microbiological studies were performed, as a result
of which 248 cultures of pathogenic and conditionally pathogenic microorganisms
were isolated, namely: 146 (58,8%) cultures of Staphylococcus aureus, 33 –
(13,3%) conditionally pathogenic staphylococci, 31 – (12,5%) Streptococcus agalactiae,
13 – (5,2%) Streptococcus dysgalactiae, 25 – (10%) of the family of
Enterobacteriaceae.
For 2019 and 2020 the allocation percentage of Staphylococcus aureus was
58,8%, which exceeds the allocation percentage of conditional pathogenic staphylococci
4,4 times, agalactiae 4,7 times and dysgalactiae Streptococcus 11,3%, enterobacteria,
5,9 times, respectively.
After examining the areas of growth retardation of Staphylococcus aureus to
antimicrobial agents, both intracisternal and intramuscular, on the example of nine
dairy farms in 2019 and 2020, we revealed different resistance of the pathogen in
each of the farms we examined.
When analyzing the sensitivity of Staphylococcus aureus to antimicrobial
drugs, including complex ones, their active substance was taken into account. As a
result of the conducted studies, it was found that in all farms, the greatest sensitivity
of Staphylococcus aureus was noted to norfloxacin (35,3 mm), neomycin (33,2
mm), amoxicillin (34,5 mm), benzylpenicillin-procaine (33,6 mm), marbofloxacin
(34,5 mm). The lowest sensitivity of the microbe was found to cloxacillin (26,6
mm), dioxidin (22,5 mm), and spiramycin (25,5 mm).
Thus, Staphylococcus aureus has different resistance to antibiotics, and the use
of antimicrobial agents with low effectiveness can lead to a chronic form of mastitis.
In this regard, and to achieve effective treatment, it is necessary to identify
the causative agents of inflammation of the mammary gland of cows, as well as to
analyze their sensitivity to the antibacterial drugs used in the farm.
The article was completed in accordance with state task N 0578-2019-0003.
Keywords
mastitis, resistance, Staphylococcus aureus, opportunistic pathogenic microflora, streptococci, enterobacteria, antibiotics.
