Microsatellites linked to Salmonella enterica Serovar Enteritidis burden in spleen and cecal content of young F1 broiler-cross chicks

Contamination of poultry and poultry products by Salmonella enterica Serovar Enteritidis (SE) continues to be problematic even though biosafety management practices have aided in reduction of the SE burden. Identification of molecular markers linked to disease resistance loci would further reduce SE burden by enabling selection for genetic resistance. The objectives of this study were therefore to evaluate specific genomic regions for resistance to SE burden in young broiler-cross chicks and to evaluate the interaction of allele with dam line and sex. Three hatches of F1 chicks were produced by crossing sires from a broiler breeder male line with hens from three highly inbred lines (Fayoumi 15.2, and MHC-congenic G-B1 and G-B2 Leghorn). At 1 d of age, the chicks were intraesophageally inoculated with SE phage type 13a. Spleen and cecal content samples were harvested at 1 wk, and the levels of SE were quantified by serial plate dilution. Each of the F1 chicks was genotyped with four microsatellites that had previously been shown to be linked to antibody response to SE vaccine. All four microsatellites had a significant (P < or = 0.05) main effect or interaction with dam line or sex on the level of SE in spleen and cecal contents.