Pet-Specific Care for the Veterinary Team

Samson is a well‐bred, accomplished German shepherd dog whose owner was approached by a friend who wanted to breed his very nice female German shepherd dog to Samson. Although Samson had quality hip conformation, Samson's uncle had poor hip conformation, so Samson's owner studied the OFA health registry for the health clearances of the female. The potential dam, and all her relatives, had good‐quality hip conformation. Samson's owner agreed to the breeding because the risk of hip dysplasia in the offspring was very low and in fact, the puppies all had good hip conformation at adulthood.

The owner of Benji, a Bengal cat, read about progressive retinal atrophy in the breed, an autosomal recessive disease that causes blindness. Both carriers and homozygous normal cats will have normal vision; only if the Bengal is homozygous for the progressive retinal atrophy‐b mutation will it be blind. The genetic mutation test revealed that Benji was a carrier. Benji's owner was relieved that the cat would not go blind. Furthermore, the test results were submitted to the genetic health registry and future and current Bengal cat owners could use that information in their own decisions.

Health registries serve multiple roles, all of which are designed to protect and promote the health of companion animals.

Genetic health registries compile health data provided by owners or veterinarians and have the greatest utility with broad participation.

Veterinarians should encourage current and future owners of all companion animals to do health screenings and submit all relevant results to health registries.

Veterinarians and owners should explore the information in health registries and use that knowledge in selecting pets to promote overall pet health.

Health registries form the backbone of research, which enables the development of genetic tests to reduce disease.

A great many of the genetic tests available have not yet been fully validated or do not apply to a given breed. With the proliferation of genetic testing companies that screen for hundreds of mutations simultaneously and the aggressive marketing directly to owners, veterinarians must counsel against the tendency to misapply or overextend results from genetic tests. Whereas many current genetic tests may be recorded in a health registry, many may have no relevance to the individual animal because the test may only be valid in a different breed. Thus, there is a growing need for understanding and interpreting test results and applying those judiciously to the pet as a whole.

OFAOrthopedic Foundation for Animals

1 Bell, J.S. (2011). Researcher responsibilities and genetic counseling for pure‐bred dog populations. Veterinary Journal 189 (2): 234–235.

2 Farrell, L.L., Shoenebeck, J.J., Wiener, P. et al. (2015). The challenges of pedigree dog health: approaches to combating inherited disease. Canine Genetics and Epidemiology 2 (3).

3 Moses, L., Niemi, S., and Karlsson, E. (2018). Pet genomics medicine runs wild. Nature 559 (7715): 470–472.

4 O'Neill, D.G., Church, D.B., McGreevy, P.D. et al. (2014). Approaches to canine health surveillance. Canine Genetics and Epidemiology 1 (1): 2.

Jerold S. Bell, DVM

Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA, USA

We see genetic disease in patients every day. The hallmark of genetic disease is its predictability. Therefore, we have the opportunity to intervene and lessen its impact for our patients. This includes prepurchase discussions with clients, recommendations on initial examination and throughout the life of the patient, and prebreeding evaluation. The hospital team should be knowledgeable about the genetic tests available, their proper use and interpretation, breed‐specific hereditary predispositions, and proper genetic counseling for both owners and breeders of dogs and cats.

Purposefully Bred:A description indicating the intentional breeding of two animals, compared to the random matings that tend to occur in nature.

The predisposition to genetic diseases is lifelong. Consequently, these must be treated as chronic diseases and not just requiring intermittent treatment during clinical episodes. The opportunity to genetically counsel our clients occurs throughout the pet's life (see 1.2Providing a Lifetime of Care). The most common examples are allergies in dogs and feline lower urinary tract disease in cats.

If a client asks about adopting or purchasing a new dog or cat, the hospital team can discuss breed or mixed‐breed anatomical and behavioral expectations and whether they fit with the client's lifestyle and home environment (see 3.10Advising Clients on Selecting an Appropriate Pet). Terrier and terrier‐type dogs have very different behavioral characteristics from retrievers or shepherds. Long‐haired versus short‐haired cats and dogs have different grooming requirements.

If the client is purchasing a purebred dog or pedigreed cat, there are breed‐specific prebreeding health screening recommendations for the parents. For dogs, these can be found at the OFA Canine Health Information Center ( www.ofa.org/breedtests.html). Common genetic disorders and tests for cat breeds can be found on the International Cat Care website ( https://icatcare.org/advice/?per_page=12&categories=cat‐breeds).

Online resources contain information on DNA tests available in dogs and cats from multiple laboratories. One can search by breed, disease, or laboratory. Some resources also link to the original published article on each disease test, as well as which laboratories run the tests: ( http://research.vet.upenn.edu/WSAVA‐LabSearch). Such resources may list identified mutations, including rare mutations that may not be present in breeding populations. Many commercial genetic testing companies test and report unvalidated mutations that have no relevance to the dog or cat being tested. Caution and diligence must be exercised when providing counseling recommendations based on genetic test results (see 3.6Genetic Testing).

Health‐conscious breeders are happy to provide official documentation of the results of health screening. The results of a puppy's parents' health screening can be looked up on the OFA website ( www.ofa.org). Many other countries have searchable health testing databases, although there are more for dogs than for cats.