All unstressed L. monocytogenes isolates were sensitive toward the tested antibiotics (Table 2). However, some variation in the susceptibility of unstressed isolates was noted, for example, the meat isolate was more susceptible to streptomycin than the ATCC strain or the dairy isolate. The latter was the most susceptible to tetracycline, ciprofloxacin and enrofloxacin while the ATCC strain was more susceptible to gentamicin, penicillin and vancomycin. All isolates showed the same susceptibility to ampicillin and doxycycline