Antibiotic susceptibility characteristics of opportunistic gram-positive bacteria in poultry microbiocenosis

Opportunistic pathogenic microflora inhabiting microbiocenoses associated with broiler chickens were studied. Gram-positive bacteria were studied in biomaterial from broiler chickens that were given the antibiotic avilamycin and a phytobiotic based on Brassica juncea, Linum usitatissimum, and Nigella sativa L. oils as an additive to the diet. The dynamics of the species composition of Staphylococcus spp., Enterococcus spp., phenotypic susceptibility to antibiotics vancomycin, ofloxacin, levomycetin, tobramycin were analyzed. Itwas found that the introduction of avilamycin into the diet of chickens led to a twofold decrease in the number of opportunistic cocci in the biomaterial from chickens. In the broiler biomaterial from the groups receiving phytobiotic, no antibiotic-resistant isolates of gram-positive cocci were detected, while the largest number of isolates were susceptible to antibiotics at a low value of the minimum suppressive concentration.