THE ANALYSIS OF THE EFFICACY OF ANTIMICROBIAL DRUGS AGAINST BACTERIAL AGENTS CAUSING MASTITIDES IN COWS
The article presents the data on the degree of sensitivity of bacterial agents causing the mammary gland inflammation in cows to 16 antimicrobial drugs from 9 pharmacological groups, obtained as a result of multicenter studies of 80 milk samples from cows with clinical signs of mastitis. In the milk of cows with mastitides, coccal microflora, including staphylococci (27.5 %), streptococci (25.4 %), enterococci (20.5 %), as well as enterobacteria (23.2 %), pseudomonas (3.4 %), was found in more than 70 % of cases. The sensitivity of the isolated cultures to the studied antimicrobial drugs in most cases was quite low and widely varied within the pharmacological groups (penicillins, aminoglycosides) and among strains of microorganisms within the genera (staphylococci, streptococci, enterococci). In isolated cultures, on average, sensitivity above 40 % was detected only for two pharmacological groups - aminoglycosides (gentamicin - 62.3 %, neomycin - 49.3 %) and fluoroquinolones (norfloxacin - 45.2 %, enrofloxacin - 54.1 %), the remaining 7 groups were less effective - tetracyclines (tetracycline - 36.3 %, doxycycline - 30.1 %), ansamacrolides (rifampicin - 31.5 %), penicillins (amoxicillin - 32.2 %, ampicillin - 31.5 %, penicillin - 21.9 %), nitrofurans (furazolidone - 17.1 %, furagin - 25.3 %), macrolides (erythromycin - 10.9 %), lincosamides (lincomycin - 6.2 %), sulfanilamides (sulfathiazole -4.1 %). The detected variability of the efficacy of the antimicrobial drugs, including those from similar pharmacological groups, with respect to the strains of isolated bacterial agents of the mammary gland inflammation, requires the obligatory determination of antibiograms for them for the effective treatment of mastitis in cows.