Project Number: 6612-32000-042-00
Project Type: Appropriated

Start Date: Sep 01, 2002
End Date: May 31, 2006

Objective:
1. Investigate why Salmonella enteritidis strains vary in their ability to contaminate eggs and why it is the only serotype to routinely contaminate eggs. 2. Identify appropriate molecular targets that can be used to conduct epidemiological monitoring. 3. Continue to improve challenge models for use in birds in order to design better vaccines and to evaluate their ability to protect chickens from SE infection and internal contamination of eggs.

Approach:
Chemotype serotypes of Salmonella to correlate LPS O-chain microheterogeneity and genetic variation. Perform ribotype and multi-locus sequence analysis to identify genetic changes that correlate with phenotypic heterogeneity. Investigate mobile genetic elements within the chromosome of Salmonella enteritidis (SE) to determine if they are a source of genetic or phenotypic variability. Analyze proteotomes of SE, S. Pullorum and S. Typhimurium and appropriate mutants to identify differences between strains with enhanced oral invasiveness as compared to an enhanced ability to contaminate eggs. Continue to improve the laying hen infection model in order to design better vaccines by providing to industry a better way to evaluate efficacy and the ability of immunization to prevent egg contamination. Investigate how infection of birds with mixed phenotypes of SE influences the incidence of contaminated eggs following infection of birds.

Project Team

Bouldin, Jean Mitchell, Bailey Swayne, David

Project Annual Reports

FY 2003