Escherichia coli is one of the most important pathogens in poultry farms around the world, causing colibacillosis and early chick mortality. Outbreaks cause heavy economic losses as primary pathogen and comoribund with other diseases. The report presents

an outbreak of colibacillosis with mortality of 12.50% in one-week old Karaknath chicks at an organized poultry farm in Meerut. The cases were diagnosed on the basis of history, clinical findings, postmortem investigation and laboratory examination. The ailing chicks were weak and dejected, with stunted growth, respiratory discomfort and vent pasting. Postmortem examination revealed polyserositis with fibrinous hepatitis, pericarditis, peritonitis, air sacculitis and omphalitis. The E. coli isolates were obtained from the infected tissues of dead chicks and cloacal swabs of sick birds using bacteriological and biochemical techniques. The isolates were resistant to amoxicillin/clavulanic acid, ampicillin, cefuroxime, tetracycline, norfloxacin and enrofloxacin, but showed sensitivity to ampicillin/sulbactum, amikacin and gentamicin. The apparently healthy and ailing chicks of the farm were treated with gentamicin @ 5-10 mg/kg body weight orally for 5 days. Multivitamin @ 5 g/L was given in drinking water for 3 days to improve the immunity. Treatment resulted in clinical recovery of the chicks and checked further mortality at the farm.

Highlights

• Outbreak of Colibacillosis in one week old Karaknath chicks.
• Carcass of chicks revealed polyserositis with marked omphalitis.
• Gentamicin was antibiotic of choice for treating ailing chicks resulting in recovery.