ASSOCIATION BETWEEN ALLELES OF THE OVINE MAJOR HISTOCOMPATIBILITY COMPLEX AND RESISTANCE TO FOOTROT

Variation in natural resistance to footrot may be genetically derived, implying that genetic markers for resistance may exist and allow sele ction of superior animals. In this study association between variation within the ovine MHC class II region and resistance to footrot was in vestigated in two trials. Half-sib progeny were subjected to a field c hallenge with footrot and their condition subsequently recorded. The a nimals were then typed at their MHC class II loci to investigate assoc iations between inherited paternal haplotype and footrot status. In th e first trial an association between MHC haplotype and footrot status was observed across all animals (P = 0.005), when the self-curing and resistant animals were combined (P = 0.002) and when the self-curing a nimals were excluded from the analysis (P = 0.001). No association was observed in the second trial, a result attributed to the dry weather conditions which led to poor disease transmission and unreliable disea se classification.