Hip dysplasia in Estrela mountain dogs: Prevalence and genetic trends 1991–2005

• Published in: The veterinary journal (1997) 2009-11, Vol.182 (2), p.275-282
• Main Authors: Ginja, M.M.D., Silvestre, A.M., Colaço, J., Gonzalo-Orden, J.M., Melo-Pinto, P., Orden, M.A., Llorens-Pena, M.P., Ferreira, A.J.
• Format: Article
• Language: English
• Subjects: animal genetics; Animals; breeding value; Breeding values; canine hip dysplasia; disease prevalence; disease prevention; disease severity; Dog; dog breeds; Dogs; epidemiological studies; Estrela (dog breed); Federation Cynologique Internationale scoring system; Female; genetic disorders; Hip dysplasia; Hip Dysplasia, Canine - diagnostic imaging; Hip Dysplasia, Canine - epidemiology; Hip Dysplasia, Canine - genetics; hips; longitudinal studies; Male; methodology; morphometry; Ortolani method; Ortolani sign; Pedigree; Portugal - epidemiology; Prevalence; Prospective Studies; Radiography; reference standards; risk assessment; risk factors; selection criteria; Threshold model; validity
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2008.06.014

Three hundred and thirteen Estrela mountain dogs were examined for hip dysplasia (HD) using the standard ventrodorsal hip extended view, and graded into five categories (A, B, C, D and E) using the Fédération Cynologique Internationale’s (FCI) scoring system. The Ortolani method was performed to evaluate hip joint laxity. Pedigree information was obtained from the Portuguese Kennel Club and the genetic trend was evaluated by calculating the mean breeding values (BVs) for the last 15 years, using the threshold model. HD was found in 66% of the dogs. There was low-moderate correlation between the results of the Ortolani test and FCI hip scores ( r s = 0.386; P < 0.001). Grades of hip dysplasia were equal in both males and females ( P = 0.14) and in the animals’ right and left sides ( P = 0.51). The mean BVs for HD were stable in dogs born between 1991 and 2003, and showed an improvement in 2004 and 2005. The data confirm the high prevalence and severity of HD in predisposed breeds that do not have breeding programmes in place. It also confirms an initial favourable change in BVs that is a likely consequence of the voluntary radiographic hip-screening programme.