Breeding a Better Dog
Canine Hip Dysplasia (HD) and Elbow Dysplasia (ED) are inherited developmental joint disorders. The malformation characteristic of both ED and HD leads to osteoarthritis, with the clinical manifestation of lameness or abnormal gait worsening with advancing age. There is an estimated 60–70 million pet dog population in USA households. Because osteoarthritis caused by HD and ED is incurable and progressive, it is increasingly important to improve hip and elbow joint conformation and thus reduce the incidence of osteoarthritis in these joints through selective breeding.
The OFA established a voluntary registry to certify dogs based on their hip and elbow conformations, in order to provide selection criteria and breeding principles for pet dog breeders and owners to lower the occurrence of inherited ED and HD and secondary osteoarthritis in dogs.
In addition, we have developed a search tool for pure-breed dog breeders, buyers and both current and prospective owners, as well as veterinarians and researchers, to enable data-driven selection to improve the orthopedic health of pure breed dogs for breeding and purchase based on their genetic potential for good hip and elbow conformation. Estimated breeding values (EBVs) provided are derived from statistical models combining pedigree relationships with Orthopedic Foundation for Animals (OFA) Hip and Elbow Scores, all of which were provided by the OFA (OFFA.org) and are in the public domain. Some dogs will have elbow EBV's even though they were never phenotyped because the bivariate model uses their hip score to estimate their elbow score. The two traits are genetically correlated.
About our Database
- We calculated breeding values for all pure breed dogs registered in the public OFA database.
- In order to maximize accuracy of the estimate, only breeds in which over 400 individuals are represented in the public OFA database were used for the calculations.
- PLEASE NOTE THAT ONLY DOGS WITH DATA IN THE OFA REGISTRY AND ONLY DOGS WHOSE RECORDS WERE PERMITTED TO BE MADE PUBLIC AND ONLY BREEDS WITH AT LEAST 400 INDIVIDUALS IN THE PUBLIC PART OF THE OFA REGISTRY ARE IN THIS BREEDING VALUE SITE. SOME DOGS MAY HAVE BEEN REMOVED BECAUSE THERE WERE ERRORS IN THE WAY THEIR INFORMATION WAS RECORDED IN THE OFA WEB SITE, E.G . YEAR OF BIRTH BEFORE THAT OF A PARENT, WRONG SEX ETC.
- We provide breeding values and inbreeding coefficients. Inbreeding coefficients (COI) are artificially decreased ON THIS SITE because we do not have access to all records on pure breed dogs USED FOR BREEDING in the USA. THESE COIs WERE CALCULATED USING ALL DOGS IN PEDIGREES THAT WERE AVAILABLE BACK TO 1974.
- OFA scores are ranked with excellent hips being given a 1 (the lowest score) and worsening scores given a 2, 3 and so on, with 7 as the worst score.
- Elbows are ranked similarly, however, only four possible scores are used.
Therefore, lower estimated breeding values indicate better hip and elbow genetic quality.
- Hip EBVs range from -1.027 (best genetic quality) to +1.781 (worst genetic quality) over all breeds.
- Elbow EBVs range from -0.154 (best) to 0.682 (worst) over all breeds.
- Accuracy of the prediction is based on the number of progeny and relatives available to estimate each dog's genetic quality. The more progeny and relatives available in the calculations, the higher the accuracy. Accuracy ranges from 0 (least accurate) to 1 (perfect accuracy). The accuracy is decreased because we can only use and release public records.
- The hip or elbow EBV is also presented in graphical form accompanied by an error (feathering) that surrounds the estimate as well as the average hip and elbow EBVs for the breed of interest. This visual information allows the viewer to relate the genetic quality of each dog in respect to the error of each estimate. We suggest you identify dogs in the lower quarter to lower half of breeding values for the pool of suitable dogs for your breed. The data used to create the breeding values offered here was drawn from dogs born up to 2014.
- The concept for this graphical presentation was illustrated by Dr. Tom Lewis of the Animal Health Trust, Newmarket, United Kingdom, during a seminar he presented at the Tufts Annual Dog and Cat Genetics Conference, Boston, Massachusetts, Sept. 27-29, 2013. His presentation was entitled “Comparative Analyses of Genetic Trends and Prospects for Selection Against Hip and Elbow Dysplasia in 15 UK Dog Breeds.”
- You can read the related research article describing the criteria used for determination of OFA hip and elbow scores here. A new paper is in process describing the results of our new analyses. This new paper will clearly show the detrimental effect of not placing all OFA records in the public domain.