Probiotic potential of enterococci isolated from canine feed.

Enterococci isolated from 28 different commercially available feeds (10-1000 CFU/mL) were identified and their probiotic potential was determined. Species identification of 22 selected strains was performed by intergenic length-polymorphism analysis (tRNA-PCR); PCR products were analyzed using capillary electrophoresis. Six strains were allotted to the species Enterococcus faecium, four to E. faecalis, one to E. hirae; the remaining strains were not classed. The strains were sensitive to vancomycin, ampicillin, tetracycline and rifampicin. They were able to adhere to human as well as canine intestinal mucus. They produced lactic acid (0.99-1.04 mmol/L) and most of them were urease-positive with sufficient survival in 5 % Oxgall-bile. They did not show any inhibitory activity due to antimicrobial substances. Plasmid DNA was detected in 8 strains, the bands responding to small molecular size (10 kbp). Considering all probiotically important properties, E. faecium strain EE3 was suggested as potential feed additive.