Vaccines have been produced but most of the current vaccines are undefined mutants produced by chemical mutagenesis or by isolating ‘atural’mutants of wild-type strains. The current project aims to A) produce a combined Salmonella Enteritidis/Typhimurium vaccine that protects against shedding and colonization by strains of both serotypes in broilers, and B) a Salmonella Gallinarum vaccine that protects against fowl typhoid in layers. Established in vivo models will be used to provide the safety and efficacy data, and finally dosage and administration methods will be investigated to generate technical proof-of-concepts for both vaccine preparations.