Aetiopathology of naturally occurring upper respiratory tract infections of rabbits in Himachal Pradesh

Aetiopathology of naturally occurring infections of the upper respiratory tract of 59 rabbits was investigated at necropsy. Lesions of rhinitis were observed in 26 (44.1%) cases comprising catarrhal (9), serous (7), purulent (6) and fibrino-necrotic (4) changes. The bacterial aetiology associated with different types of rhinitis were, S. aureus, B. bronchiseptica, E. coli, Pseudomonas spp. and mixed infection of Streptococcus spp. and Shigella spp. Tracheitis was recorded in 20 (33.9%) cases with catarrhal (10), purulent (7) and fibrinous and necrotic (3) lesions. The bacteria associated with different types of tracheitis included, S. aureus, K. pneumoniae, E. coli, B. bronchiseptica, Enterobacter spp., Shigella spp., Proteus spp. and mixed infections of S. aureus and B. bronchiseptica, S. aureus and E. coli, Corynebacterium spp. and Shigella spp. Rhinitis and tracheitis were concurrently observed in 9 (15.3%) cases with serous rhinitis with catarrhal tracheitis (3); purulent rhinitis and tracheitis (4) and fibrinous and necrotic rhinitis and tracheitis (2). The findings suggest varying inflammatory response of upper respiratory tract of rabbit to a variety of naturally occurring infecting bacterial agents where S. aureus was more frequently involved.