Phenotypic Identification and Antibiotic Resistance Profile of Escherichiacoli Isolated from Lambs with Colibacillosis in Mosul, Iraq

Neonatal diarrhea and colibacillosis generally lead to critical morbidity and mortality ratesin affected sheep flocks caused by Escherichia coli (E. coli). The aim of this study was to detect andisolate E. coli from lambs with dysentery and their antibiotic resistance profile. 67 Rectal swabs fromaffected lambs in different regions of Mosul city were collected and cultured in MacConkey brothand incubated aerobically for 24 hours at 37ºC to cultivate and decrease the growth of undesiredbacteria. Then, each sample was cultured on MacConkey, EMB, and HicromTM E. coli agar at thesame incubation conditions for isolation of E. coli. Growing and purified isolates were identifiedbased on Gram's staining reaction and biochemical IMViC tests (Indole, Methyl Red, Voges-Proskauer, and Citrate). E. coli was isolated from 65 samples (97.01%). Then, an antibiotic resistanceprofile was performed on all 65 isolates by using the disk diffusion method on 12 common antibiotics.The results of the research showed a high distribution of E. coli in affected cases, with varyingresistance patterns, especially all isolates showed absolute resistance to spiramycin, lincomycin, andceftriaxone. These findings point to the immediate requirement to reform antibiotic administrationpolicies in veterinary medicine and ensure the importance of antibiotic resistance in E. coli isolatesto find the most effective treatment strategies for colibacillosis in lambs. Future studies are needed tofind alternative treatment options and the role of antibiotic management in veterinary lines.