PREVALENCE OF ANTIBIOTIC RESISTANT STRAINS OF ESCHERICHIA COLI AND ENTEROCOCCUS SPP. IN ROE DEER (CAPREOLUS CAPREOLUS) AND RED DEER (CERVUS ELAPHUS) AT THE PARCO NAZIONALE DEI MONTI SIBILLINI, ITALY

Abstract

A case control study was performed in the Parco Nazionale dei Monti Sibillini, Italy, to find out whether roe deer (Capreolus capreolus) and red deer (Cervus elaphus) were more likely to harbour antibiotic resistant Escherichia coli in their faeces, compared to Enterococcus spp. Ten areas were selected and samples were collected during a fourmonths (May to August, 2008) sampling period. Samples of water (n=12) and feces (n=59), collected at 10 different sites, were cultured for E. coli and Enterococcus spp. The resulting colonies were screened for tetracycline, ampicillin and kanamycin resistance using the Lederberg Replica Plating method (breakpoint 4 μg/ml). All resistant isolates were then selected, and subjected to the CLSI antimicrobial plate susceptibility test (7). Among the water specimens contaminated by E. coli, 80% were found to be resistant to ampicillin, 80% to tetracycline and 40% to kanamycin. Among the water specimens contaminated by Enterococcus spp., 14.29% were found to be resistant to ampicillin, 14.29% to tetracycline and 71.3% to kanamycin. Among the 39 strains of E. coli isolated from red deer feces, 12 were resistant to ampicillin (30.77%), 5 to tetracycline (12,82%) and 3 to kanamycin (7.69%). Among the 19 strains of Enterococcus spp. isolated from red deer feces, 0 were resistant to ampicillin (0%), 1 to tetracycline (5.26%) and 19 to kanamycin (100). These are significant findings, indicating that antibiotic resistance can be found in naive animal populations and that red deer and fallow deer could act as sentinels for antimicrobial resistance. Key words Antibiotic-resistance, red deer, fallow deer, Escherichia