How do we tackle hereditary disease?
In recent years, pedigree dog health has come under increasing scrutiny in the media.
The rising trend for 'designer' dogs is cause for concern and results in owners buying puppies with a "false sense of confidence", said Cathryn Mellersh, head of canine genetics at the Animal Health Trust (AHT).
A press briefing at BSAVA Congress this morning (7 April) saw vets discussing pressing issues in dog health, including extreme conformation, hereditary disease and the vet's role in changing public attitudes to particular dog breeds.
In recent years, pedigree dog health has come under increasing scrutiny in the media, leading to greater awareness of health issues, greater pressure on breeders and the Kennel Club to solve these issues, and an increase in the available tools and resources, including sophisticated DNA sequencing technologies.
Dr Mellersh places hereditary disease in two broad categories - primary disease caused by deleterious mutation(s) and secondary disease caused by exaggerated body type - and poses two different solutions to these issues.
In the case of exaggerated body type, the only solution is for breeders to reverse what has been done by not breeding dogs with extreme traits, while clinical screening programmes and breeding programmes can be adopted to eradicate primary disease.
Mendelian diseases, typically caused by mutations in a single gene, are most amenable to DNA test. While they are usually restricted to a single or small number of breeds, cocker spaniels and miniature poodles share the same mutation for progressive rod cone degeneration, raising obvious concerns about the increasingly popular cockerpoo crossbreed. DNA testing must not, therefore, be seen as something for pure breeds only, Dr Mellersh stated.
Concerns were raised about the lack of regulation surrounding DNA tests and she advised anyone seeking a test to ensure it is based on good science, has been peer reviewed and published in the public domain.
While most puppy buyers, unfortunately, will not ask their vet for advice on which breed to choose, Dr Mellersh said vets should be able to advise breeders on DNA tests and clinical screening where possible. Vets "should not shy away" from telling owners when they have made a bad choice, she added.
Questions were raised about whether some particularly exaggerated breeds, such as shar peis, pugs and French bulldogs, should be allowed to exist at all. However, Dr Mellersh argued it is "unrealistic" to think that these breeds could be banned, and therefore it may be in the best interests of animal welfare to point owners towards the most healthy dogs possible.
It is also the responsibility of the veterinary industry to cease the promotion of unhealthy dogs in marketing and advertising.
For information on available tests visit:
WSAVA: www.wsava.org/guidelines/hereditary-diseases
Kennel Club: www.thekennelclub.org.uk/health/for-breeders
With Strangles Awareness Week just around the corner (5-11 May), vets are being encouraged to share a survey about the disease with their horse-owning clients.
