Efficacy of locally prepared Salmonella Kentucky vaccine in chicken

Document Type : Original Article

Authors

1 Central Laboratory for Evaluation of Veterinary Biologics, Abbasia, Cairo

2 Veterinary Serum and Vaccine Research Institute, Abbasia, Cairo

Abstract

In the present study, efficacy of a locally prepared Salmonella Kentucky killed vaccine 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 at four weeks, the second
group was kept unvaccinated as a control group. The two groups were challenged orally with 1 ml of Salmonella
Kentucky (5x107 CFU/ml), 3 weeks post boostering of the vaccine. The degree of protection was assessed
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 fourth week after challenge and humoral immune
response was measured against Salmonella strains using ELISA and microagglutination test. The prepared vaccine
induced 80% protection rate in challenge test with reduced fecal shedding.

Keywords