Abstract   

One hundred E. coli isolates were recovered from livers and hearts of chickens of different age groups suffering for colisepticaemia. These isolates wre subjected to in vitro antibiotic susceptibility test using eleven antimicrobial agents which included enrofloxacin, ciprofloxacin, norfioxacin, flumequin, oxolanic acid, cefazolin, gentamicin, kanamycin, amoxycillin, neomycin and sulphamethoxazole + trimethoprim by disc diffusion technique. All isolates were sensitive to enrofloxacin and ciprofloxacin whereas 98 per cent of isolates displayed sensitivity to norfioxacin. Ninety four, , 87, 80, 79, 77, 47, 32 and 8 per cent isolates showed sensitivity to cefazoline, gentamicin, flumequine, neomycin, oxolanic acid, amoxycillin, kanamycin and sulphamethoxazole + trimethoprim, respectively. A total of 22 antibiogram patterns were recorded among 100 isolates with 67 per cent displaying resistance to two or more antimicrobials (multinle drug resistance).