Gallibacterium anatis outbreaks in domestic birds in North India: Antimicrobial and herbal drug sensitivity of Avibacterium and Gallibacterium isolates

Gallibacterium anatis biovars have emerged as important poultry pathogens all over the world. However, it has rarely been reported earlier in India. Here we report eight outbreaks of the disease “Gallibacteriosis” in layers, broilers, pigeons and ducks associated with significantly high mortality in birds. The disease was clinically characterised by pyrexia with 41°C to 42°C, watery nasolacrimal discharge and diarrheic faces. A total of 28 isolates of Avibacterium and Gallibacterium isolates were identified but only G. anatis showed consistent association with the disease. All the tested isolates in the study were sensitive to gentamicin, nitrofurantoin, chloramphenicol, ceftazidime, meropenem, imipenem, azithromycin, colistin, tigecycline and aztreonam. Nalidixic acid was the least effective drug followed by cotrimoxazole, ciprofloxacin, erythromycin, tetracycline and ampicillin. Four of G. anatis biovar anatis and one G. anatis biovar haemolytica isolates produced extended spectrum β-lactamases (ESBL) and 50% isolates had multiple drug resistance. Antibiotic sensitivity and herbal antimicrobial sensitivity of other 32 bacteria isolated during the study had a wide variation in their resistance pattern. On all the six poultry farms and duckery addition of amoxicillin in drinking water (100 mg/lt) and feed (50 mg/kg) for a week controlled the morbidity and mortality while for pigeons ampicillin was administered in water (100 mg/lt) for a week to control morbidity and mortality. The study revealed that infection of G. anatis biovar anatis and biovar haemolytica in chicken, ducks and pigeons may lead to consistently high mortality, however, controllable with use of commonly available antibiotics.