Phenotypic status of elbow dysplasia in Boerboel dogs in Nigeria

Elbow dysplasia (ED) is a developmental, multifactorial, polygenic disease of rapidly growing, large breed of dogs. ED can be a significant health concern for affected dogs because treatments are largely ineffective, making selectively breeding of normal dogs the best option for disease control. Despite the relative availability of data on ED prevalence in other breeds, there is dearth of information on ED  prevalence in Boerboel dogs. This study evaluated ED prevalence and relative percentages of different ED grades in Boerboel dogs using radiographs of dogs presented for screening between April 2016 and September 2020. Extended latero-medial, flexed latero-medial and cranio-lateral-caudo-medial oblique radiographs from 64 dogs were reviewed. Radiographs were graded using international elbow working group (IEWG) criteria and grades 0-3 assigned to each joint. ED prevalence expressed as percentages were obtained by dividing the number of dogs with grades 1, 2 and 3 by total number of dogs. Age and sex difference in ED prevalence were compared using chi-square test. Differences were considered significant at P ≤ 0.05. Mean age of the dogs was 2.3 ± 0.6 years. Thirty-six (56.3%) dogs were graded as non-dysplastic, while 28(43.7%) were graded as dysplastic, with grade 3 (46.4%) accounting for majority of ED cases. There were no significant (p > 0.05) difference in sex and age prevalence of ED in the breed. In conclusion, ED prevalence in Boerboel dog is high with majority of dogs having severe grade. Widespread phenotypic screening and strict breeding restrictions are recommended| to control the disease in the breed. Keywords: Boerboel, Dog, Elbow dysplasia, Prevalence, Radiographic screenin