Isolation and identification of diarrheagenic <i>Escherichia coli</i> causing colibacillosis in calf in selective areas of Bangladesh

This study was carried out to isolate, identify and characterize Escherichia coli from diarrheic calves, their prevalence and antibiotic sensitivity pattern during the period from November 2011 to December 2012. For this purpose 100 diarrheic fecal samples were collected from four different areas of Bangladesh. The samples were aseptically collected and brought to the laboratory of Medicine, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh. The organisms were identified as E. coli on the basis of cultural, morphological and biochemical characteristics. Further the isolated bacteria were confirmed by amplification of E. coli specific 16sRNA gene. The antibiotic resistant pattern of the isolates was also performed. Out of 100 samples 49 (49%) were found to be positive for E. coli. The highest prevalence was found in Shahjadpur, Sirajganj (53.33%) while lowest was in BAU, Mymensingh (40%). The antibiogram study revealed that all isolates were resistant against ampicillin, erythromycin, azithromycin and streptomycin where erythromycin was 100% resistant, whereas 100% sensitivity was found to tetracycline and gentamicin which might be the best choice of drug for the treatment of diarrheagenic E. coli causing colibacillosis in calves.DOI: http://dx.doi.org/10.3329/bjvm.v11i2.19139Bangl. J. Vet. Med. (2013).11(2): 145-149