Short communication ANTIMICROBIAL RESISTANCE IN ESCHERICHIA COLI ISOLATED FROM DIFFERENT PARTS OF THE DIGESTIVE TRACT OF SHEEP

In order to evaluate differences in resistance patterns of Escherichia coli isolated from different parts of sheep digestive tract, the intestinal tracts of 24 sheep were sampled at various locations (duodenum, jejunum, caecum, colon and rectum) after slaughter. Samples were cultured on MacConkey agar and obtained colonies were confirmed as E. coli based on the biochemical tests results. Isolates were tested for antimicrobial agent susceptibility to 10 antibiotics (colistin, gentamicin, oxytetracycline, trimethoprim-sulfamethoxazole, amoxicillin-clavulanic acid, enrofloxacin, ampicillin, cephotaxime, neomycin and florfenicol), using disc diffusion method. The tested E. coli resistant to colistin, ampicillin and amoxicillin-clavulanic acid were isolated more frequently from large intestine (rectum) than from small intestine (duodenum) (P<0.05). In conclusion, antimicrobial resistance pattern of generic E. coli inhabiting the intestinal tract of sheep depends on sampling location, which should be considered in interpreting the results of antimicrobial resistance tests of E. coli isolated from the faecal samples and generalising results to bacteria colonised in other parts of the digestive tract.