Infectious diseases are a major cause for losses in broiler production.
Ab response to Escherichia coli vaccination. Phase 2 consisted of genotyping for the sire's heterozygous markers. Differences in mean allelic frequency between progeny of LL and HH dams provide additional indication for association between the marker and QTL of Ab response. These markers are used in Phase 3 to individually genotype all the progeny, to verify and quantify their effects and to compare them between dam types.