Isolation, Identification and Antibiotic Resistance of Escherichia Coli Strains Isolated from Broiler Chicks in Central Algeria

The present study's aim was to isolate, identify and determine the antibiogram profile of Escherichia coli in broiler chick in central Algeria, as well as to evaluate associated risk factors. A total of 41 poultry sheds, each housing between 2000 and 8000 chicks, were included in the study. These sheds were located in two regions such as tizi-ouzou and boumerdas. In total, 339 samples were analyzed by a bacteriological test. The prevalence of colibacillosis was foud to be 82,89%±2,3 ; varied according to chick age, farm size and concomitant pathogen (p<0,05). The bacterium was isolated from the liver, spleen, lungs and pericardium of chicks with isolated or multiple localizations causing extensive inflammation of the affected organ. in the study population, colibacillosis caused a high mortality rate ranging from 2 to 3,7%, depending on the rearing conditions, where it was highest if the density was high (p<0.05), chick age was also shown to be a risk factor, especially during the first 7 days (p<0,05). the Escherichia coli strains in the farms studied showed high resistance to sulfamide-trimitoprime (96,34%), ampicillin (70,73 %) and nalidixic acid and tetracycline (74,39 % and 73,17 %) but the bacteria were sensitive to colistin and genatmicin (82,93% and 81,71% respectively %). All strains exhibited multi-drug resistance, whose (70%) of the isolates showing resistance to 4 different antibiotics. In algerian poultry farming, colibacillosis remains an important pathology, causing heavy economic losses directly linked to mortality, treatment costs and stunted growth, as well as in terms of health, because the E.coli strains isolated have expressed resistance to the molecules commonly used. It is also essential to set up a programme in Algeria to monitor antibiotic resistance in pathogenic bacteria that can be transmitted to humans via food of animal origin.