DefinePK

Abstract

In the present study, efficacy of a locally prepared inactivated trivalent Salmonella vaccine consisting of Salmonella Typhimurium (ST), Salmonella Kentucky (SK) and Salmonella Enteritidis (SE) had been studied. A total of 120, two weeks old specific pathogen free (SPF) chicks were divided into two groups; 60 chicks each. First group was vaccinated with the prepared vaccine at the age of two weeks and boostered after three weeks, the second group was kept unvaccinated as a control group. The two groups were challenged with Salmonella Typhimurium, Salmonella Kentucky and Salmonella Enteritidis strains (108 CFU/ml of each) 1ml orally, 3 weeks post boostering of the vaccine. The degree of protection was detected according to the severity of the clinical signs, the mortality and fecal shedding of the challenged organisms. Blood samples were collected weekly after first vaccination till the third week after challenge and humoral immune response was measured against Salmonella strains using ELISA and microagglutination test and gives a high protective antibody titer. The prepared vaccine induced 80% protection rate in challenge test with reduced fecal shedding. These results suggest that the locally prepared inactivated trivalent Salmonella vaccine can be an effective tool for controlling the salmonellosis in chicken farms in Egypt.