Estimated Breeding Values (EBVs)
row of dogs



Breeding a Better Dog

based on the application of Breeding Values derived from OFA Hip and Elbow scores and pedigrees


Our Purpose

•  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).

 

Major Beneficiaries

•  Pure breed dog breeders
•  Pure breed dog buyers
•  Pure breed dog pet owners -current and prospective
•  Veterinarians
•  Researchers

 

OVERVIEW & FEATURES OF IMPORTANCE

About our Database

•  We calculated breeding values for all pure breed dogs registered in the OFA database.
•  In order to maximize accuracy of the estimate, only dogs in which over 400 individuals are represented in the public OFA database were used for the calculations.
•  We provide breeding values and inbreeding coefficients for all these dogs born after 2000.  However, all the OFA scores and pedigrees of all the dog's antecedents back to 1970, if available, were used to derive the current estimated breeding values and inbreeding coefficient.


Scoring Methods

•  OFA scores are ranked with excellent hips or normal elbows being given a 1 (the lowest score) and worsening scores given a 2, 3 and up to 7 as the worst score.
•  Therefore, lower estimated breeding values indicate better hip and elbow genetic quality.

•  Hip EBVs range from -2.491 (best genetic quality) to +2.791 (worst genetic quality).
•  Elbow EBVs range from -0.501 to 1.152.

•  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 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.

 

ACCESSING DATABASE

1.  Go to 'Search' page.

2.  Enter breed from pull-down menu or Registration/OFA#/Name if seeking a specific dog. (See copy of Search page below).

3.  Select sex if sire or dam are preferred.

4.  Impose an age criterion if you wish to find suitable living mates.

5.  To select dogs for best genetic orthopedic quality for hip and elbow conformation, select breeding value below -0.5 under hip criteria and relax (increase) or strengthen (decrease) this value until you have selected a set of suitable mates.

6.  Select elbow breeding value below 0.3 and decrease this number until you have a suitable set of dogs.

7.  You can also select a level of accuracy (rank 0 as lowest to 1 as highest) for both hip and elbow values.

8. Once you have selected prospective breeding dogs, rank the dogs by inbreeding coefficient.  If possible, select the dog with higher accuracy (closer to 1.0) for breeding (those in the lower half or quarter of the EBV range, and lower inbreeding coefficients).  This strategy should maintain genetic diversity while decreasing deleterious alleles from the breed.  More stringent criteria can be imposed for breeds with large populations.

ebv1



If you select Afghan Hound with hip criteria below -0.5, hip accuracy above 0.75, elbow criteria and accuracy 0.0, then you should retrieve the following list:

ebv2



Practice mating favorite pairs in silico

•  Using the 'Mate Compare' button on the right side of the return list (above image), you can select two dogs (as shown) and produce a virtual mating to observe the likely genetic quality of the offspring.


ebv graph

•  Therefore, based on this example, if you know there are pups available from a mating of these two dogs, then, on average, these pups should have better hip and elbow quality than pups whose breeding value is higher (toward '0' or worse).  Generally, 15-20 offspring would need to be produced, by mating the same sire and dam, to acquire reliable information regarding the genetic quality of these two dogs.  The application of breeding values obviates some of this waste and delay and will produce healthier dogs faster than using visual observation of pedigrees to select breeding pairs.