Questions & Answers

Why is this search function to find purebreeds with hip and elbow breeding values useful?

The breeding values and inbreeding coefficients recorded in this web site enable me to find dogs with low hip and elbow score breeding values that belong to the current and recent generations. The use of the dogs in the lower part of the breeding value range for breeding (or exclusion of the dogs in the upper end of the range) will improve the hip and elbow quality of my breeding stock and puppies they produce. Purchase of puppies produced by the sires and dams with the lower breeding values will result in puppies with better hips and elbows than if I based breeding decisions on hip and elbow radiographs alone. The reason is that the selection of dogs based on breeding values means that consideration has been given to both the dog's genetic (pedigree) information and radiographic information combined. Selection of dogs based on radiographs alone is very useful but faster genetic gain toward better hip and elbow conformation accrues when breeding decisions are made based on genetic information as well. This has been demonstrated in closed breeding colonies for service dogs and under controlled conditions over and over again.

 Why do more negative breeding values mean a better hip?

The question arises due to the ambiguity of word “value”, which usually suggests the higher value the better. The breeding value is an indicator for the genetic basis of the hip and elbow score variation. Consequently, breeding values take the same unit and direction as the original phenotype – the OFA score. An OFA score of 1 is for an excellent hip and an OFA score of 7 is for the most severe hip dysplasia. For elbows, an OFA score for unaffected elbows is given a 1 and the worst elbow dysplasia is given a 4.

What is the difference between expected progeny difference (EPD) and breeding value?

The breeding value is the prediction of the genetic basis of an individual OFA score. Half of the genetic basis is contributed from one parent and half from the other. If an individual is mated randomly, the expected difference of the progeny from the average (base) of the entire breed will be the half of the breeding value. Therefore, half of the breeding value is called the EPD. For example, sire A and B have breeding values of -0.1 and 0.20, their EPDs will be -0.05 and 0.1. The progeny of sire A is expected to be 0.15 lower (better genetic quality) than the progeny of sire B if mated to the same dam.

Will an inbred dog definitely have progeny with high inbreeding?

Not really. The progeny may not be inbred if the mate you select is not its relative. Inbreeding of an individual depends on whether both parents are close relatives or not.

Why can breeding value be negative?

The  current reported breeding values were the direct output of the statistical solutions for each dog in the mixed linear model. The base, or overall average, of the breeding value is the average breeding value among all the dogs evaluated. The base is a “floating” base which can vary by adding new dogs which have better hips or elbows or worse hip or elbow scores.

I wish to choose a pup from a litter and I know the parents who produced this litter. How should I use the information in the data base?

Once  you decide the breed characteristics of the parents you prefer, then gather the information about any inherited traits and diseases you can. For a pup’s genetic potential to grow up with good hip or elbow quality, go into the data base and look at the breeding values for the dogs you like. Then you can rank those dogs based on their potential to produce pups with good conformation. (The lowest hip and elbow breeding value indicate the dog with the genetic potential to produce the best conformation based on the OFA score.  In the database, the dogs are automatically ranked that way) If only one parent is found in the data base, then that’s the best you can do. Secondly, you can rank the parents according to the accuracy of the breeding value (higher accuracies are preferred) and then on their inbreeding coefficients. You should try to choose pups produced from litters whose parents have the lowest inbreeding coefficients and highest prediction accuracies among those with the lowest EBVs.

I wish to choose a pup from a litter but I don’t have information about the hip or elbow scores of either parent.

You can ask the breeder for any pertinent radiographic information they have about their dog. They may have PennHIP information. They may do no orthopedic screening at all. If you obtain no information about orthopedic health in a dog’s pedigree, then we suggest you try another breeder.

I wish to buy a male dog as a potential breeder. How should I use the information in the data base?

Once you have selected the potential male dogs based on all the breed qualities you prefer, then rank the dogs based on their genetic potential to produce offspring with good hip and elbow conformation and on their inbreeding coefficients and the accuracy of the breeding values. Always breed to a female dog with the best hip and elbow conformation (lowest EBVs) and lowest inbreeding coefficient you can find along with all the best qualities you can ascertain, orthopedic or otherwise.

I wish to buy a female dog as a potential breeder. How should I use the information in the data base?

Once you have selected the potential female dogs based on all the breed qualities you prefer, then rank them based on their genetic potential to produce offspring with good hip and elbow conformation (lowest EBVs) and on their inbreeding coefficients. Always breed to a male dog with the best hip and elbow conformation and lowest inbreeding coefficient you can find along with all the best qualities you can ascertain, orthopedic or otherwise.

I bought a pup already but just found this web site. How should I use the information in the data base to decide if this puppy is at risk of hip or elbow dysplasia?

If you can identify the parents in the data base, look at the OFA breeding values of the parents. If they are well above 0, then the pup has a higher chance of developing hip or elbow dysplasia than if the breeding values are well below 0. The lower the breeding value is, the lower the susceptibility, or risk, to develop hip or elbow dysplasia. If you decide the pup is susceptible, it should be examined regularly for hip instability and elbow discomfort by your veterinarian. Depending on the dog’s age, medical or surgical intervention may be an option. This is especially important if your dog has clinical signs of hip dysplasia like reluctance to jump, bunny hopping gait at speed (both hind legs moving forward together), soreness or stiffness after exercise, a “wobbly” hind limb gait, poor muscle mass development behind compared to its forequarter, difficulty getting up, placing extra body weight on its fore limbs with a hunched back, a clicking sound when it walks, or reluctance to allow you to pet near its hips. Dogs with sore elbows from elbow dysplasia will also have lameness and resent elbow manipulation and often have swollen elbow joints. Any pup susceptible to hip or elbow dysplasia or any developmental orthopedic disease should be watched for rapid body weight gain and if it is too fat, its food intake should be restricted under advice of your veterinarian.

If a puppy is at risk for hip or elbow dysplasia based on the breeding value of its parents, what should I do about it?

Ask  your veterinarian to examine your puppy’s hips and elbows regularly. This is especially important if your dog has clinical signs of hip dysplasia like reluctance to jump, bunny hopping gait behind at speed (both hind legs moving forward together), soreness or stiffness after exercise, a “wobbly” hind limb gait, poor muscle mass development behind compared to its forequarter, difficulty getting up, placing extra body weight on its fore limbs with a hunched back, a clicking sound when it walks, or reluctance to allow you to pet near its hips. Dogs with sore elbows from elbow dysplasia will also have lameness and resent elbow manipulation and often have swollen elbow joints. Any pup susceptible to hip or elbow dysplasia or any developmental orthopedic disease should be watched for rapid body weight gain and if it is too fat, its food intake should be restricted under advice of your veterinarian. 

Once I have identified a litter for puppy selection or a dog to which I'd like to breed, how do I locate the owner or breeder?

We suggest trying Google, other owners of dogs with the same breed, breed/trade magazines, contacting the breed clubs, or the AKC, etc. There are many resources available on the web to help in your search. You can also purchase a pedigree from the AKC using a dog’s pedigreed name and this will have an owner's name on it.