Pathomicrobial studies on Salmonella Gallinarum infection in broiler chickens

Aim: To conduct detailed pathomicrobial studies on Salmonella Gallinarum infection in broiler chickens. Materials and Methods: Bacteriological and pathological studies were conducted on 134 dead poultry birds collected from 23 different farms suspected to be infected with S. Gallinarum. Results: Mortality pattern revealed that maximum mortality occurred in 1-2 week aged birds. Out of 23 Salmonella isolates, 19 samples were identified as S. Gallinarum (9, 12) and 4 samples as Salmonella Enteritidis (9, 12: gm). Isolates were found to be most sensitive to Polymyxin B (100%). The present study also showed re-emergence of chloramphenicol sensitivity (83.33%). Pathological lesions observed were bronze discolouration of liver, splenomegaly and necrotic foci on liver, spleen and heart. Microscopically, liver and spleen revealed aggregation of heterophils, lymphocytes and macrophages, nonsuppurative myocarditis, fibrinous pericarditis, interstitial nephritis, necrotic enteritis and serofibrinous pneumonia. Conclusion: It was concluded that S. Gallinarum 9, 12 was the main serotype causing Salmonellosis in poultry birds. Polymyxin B was the most sensitive drug (100%) for Salmonella infection along with re-emergence of chloramphenicol sensitivity for Salmonella (83.33%) infection.