Bacteriological and molecular studies on Salmonella isolatedfrom duckling farmsatKaliobia, Egypt

This study was conducted on 21 commercial duckling farms (1- 20 days old) inspected to show Salmonella infection in different localities at Kaliobia Governorate. Samples were taken from diseased ducklings and freshly dead for bacteriological examination which resulted in, 94 samples were positive from 630 isolates, where 28 isolates from 33 diseased ducklings and 66 isolates from 72 freshly dead ducklings. Three serogroups of Salmonella were obtained by serological identification (Salmonella Typhimurium, Salmonella Enteritidis and Salmonella Blegdam). The antibiotic sensitivity tests for the isolated strains showed multiple antibiotic resistances (oxytetracycline; amoxicillin; ampicillin; streptomycin; erythromycin and trimethoprim/ sulphamethoxazol) but gentamycin, norfloxacin and ciprofloxacin are the most effective antibiotic on the isolated Salmonella and can be used for treatment of Salmonellosis in duck farms. PCR results appeared that, invA and stn genes were detected in all studied Salmonella isolates;pefA gene was detected in four out of five studied isolates but sefC genewas detected in two isolates only. Finally, isolated Salmonellae are virulant pathogens responsible for disease in ducklings resulting in high mortality and morbidity, gentamycin, norfloxacin and ciprofloxacin are the most proper antibiotics used for treatment of Salmonellosis in duck farms.