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, non-suppurative 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