Antibiotic susceptibility and biofilm-forming capacity of enterococci isolated from food of animal origin

Enterococci are found in the gastrointestinal tract of humans and animals, in soil, and in water, but they also have a long history of use in the production of traditional fermented food. Some strains of enterococci are considered as emerging pathogens of humans. The intrinsic and acquired resistance of enterococci to antibiotics has special significance. Food of animal origin may be a source of resistant enterococci. The main cause of food contamination with enterococci is improper cleaning and disinfection of equipment. The aim of this study was to assess the antibiotic susceptibility of enterococci isolated from different types of food of animal origin and the ability of these microorganisms to form biofilm. Out of a total of 63 isolates, relatively few enterococci were resistant to gentamicin (1.59%). The highest level of resistance was noted for vancomycin (7.94%) and ampicillin (9.52%). However as many as 19.05% and 44.44% of enterococci were resistant to erythromycin and tetracycline, respectively. The ability to form biofilm was detected in 14.29% of the strains of enterococci tested.