Abstract
Respiratory infections are major cause of death in rabbits, which are often caused by bacterial pathogens. The present study was conducted to determine the occurrence of streptococcal infections with pneumonia in rabbits through macroscopic, microscopic pathological and bacteriological examination. A total of 45 rabbits that died between October 2025 and February 2026 were brought for postmortem examination to the Department of Veterinary Pathology of the College in Rajendranagar, Hyderabad. Among them 29 were bunnies (2 to 6 months) and 16 adult rabbits (6 months to 3 years). The necropsy was conducted as per protocol in clean environment. 9 adult rabbits and 20 bunnies showed pneumonia lesions on postmortem examination. Necropsy findings showed consolidation in lungs, fibrinous exudation, abscess and pleuritis. Microscopic analysis of lung smears revealed Gram-positive cocci organized in chains. Histopathology of lungs revealed suppuration, inflammatory cells infiltration, emphysema and haemorrhage. The organism was isolated on Edwards medium and characterized by colony morphology and biochemical traits, including negativity for catalase, oxidase and positivity for bile esculin. These findings confirmed presence of streptococcal species associated with pneumonic lesions in rabbits and emphasize the importance of bacteriological and histopathological investigations for accurate diagnosis of respiratory infections.
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