common feature in these isolates, highlighting the fact that the resistance genes for
these drugs are linked on plasmids.(32) Moreover, the wide spread resistance to
cotrimoxazole may be implying the presence of class 1 integrons, which are also
important in conferring resistance to multiple anti-microbials.(33)
Norfloxacin was incorporated in many of the patterns observed in the present study
especially the predominant ones. This probably points to the fact that the E. coli
strains encountered in these free-range poultries might have originated from human
hosts where their resistances to fluoroquinolones were first selected and
subsequently disseminated to lower animals.(5) There is strong evidence that anti-
microbial use in humans has not only driven the emergence of multi-drug resistant
clones in the developing countries such as Nigeria that has resulted in an
increasingly high prevalence of multiple resistance.(8-11)
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OJHAS Vol 4 Issue 3, 2005-3-3: Original Article. Antimicrobial resistance profile of E.coli isolates from tropical free range chickens. www.ojhas.org/issue15/2005-3-3.htm
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