International Journal of Veterinary Sciences and Animal Husbandry

Abstract

Canine hip dysplasia is a polygenic disorder having genetic and non-genetic components. Divergent breeding lines for working dogs (livestock guardians) and non-working dogs (pets) gave rise to different selection pressure and differences in hip morphology and prevalence in this giant breed. We investigated morphological and genetic traits associated to Canine Hip Dysplasia in the Spanish mastiff. Norberg angle was used to diagnose this disorder, with agreement between evaluators assessed. Validity of a genetic test based on the Fibrillin-2 gene in distinguishing presence of Canine Hip Dysplasia was evaluated. Relationships between Norberg angle, sex, Fibrillin-2 genotype and morphology of working and non-working dogs were analyzed. Directional asymmetry was also found, in most cases related to animal manipulation during radiography. Standardization of radiography and Norberg angle measurement is crucial to diagnosis of Canine Hip Dysplasia and to avoid evaluator’s bias.