Lethality and invasiveness factors in Salmonella Gallinarum strains of avian origin

Lethality and invasiveness of six wild strains (SG5, SG13, SG31, SG42, SG68 and SG73) of Salmonella Oallinarum, isolated from outbreaks of fowl typhoid at different commercial poultry flocks of Gujarat State, was determined in day old chicks revealed all to be equally invasive with no apparent difference in the viable counts in liver of inoculated chicks. The strains 805, 8031, 8042 and SG68 caused 33.3, 26.6, 6.66 and 6.66 percent mortality respectively, while SG13 and SG73 induced 40 and 60 per cent mortality in chicks respectively. The results revealed that lethality and invasiveness as two different pathological attributes and the variability may be due to strain variation.