Importing and exporting: Do we understand the health consequences?

Over many years, UK breeders have established a reputation for exporting good quality dogs overseas. Many go on to become Show Champions, often to a new career as a stud dog or breeding bitch. Some overseas kennels proudly advertise that they have imported UK-bred stock to improve their line.

There is a similar story with imports; importing new bloodlines has long been a valuable way in which breeders and exhibitors can improve the quality of their stock, as well as adding to the diversity of the UK gene pool.

As well as exporting or importing desirable traits and genes, there is also the risk of exporting or importing undesirable ones. The fact that we now have a variety of clinical and DNA tests available for a range of conditions means responsible breeders can reduce the risks and share the knowledge about potentially dangerous mutations with breeders outside the UK.

Lafora Disease in Mini Wires serves as a particularly current example. Whilst Lafora can occur naturally in any breed, it is known to affect around 10% of the UK Miniature Wirehaired Dachshund population and they may go on to develop debilitating epilepsy, blindness and dementia in later years. As many as 40% of UK Miniature Wires carry a single Lafora gene, inherited from one parent (i.e. they are Carriers). Whilst the dog itself won’t show any symptoms, it can pass that gene on to future progeny. Over the last few years a number of Miniature Wire-haired Dachshunds have been exported to, or spent time, overseas for show and/or breeding purposes. Some Mini Wires that have been exported have been known to be Lafora carriers, and in one instance, as affected.

Last year, the WHDC wrote to a number of overseas Breed Clubs to advise that dogs exported from the UK over the last few years may have carried the Lafora gene, which means that no breeder should assume that it is safe to breed from any dog with UK genes without first Lafora testing. We hope that information and advice for overseas breeders has been passed on by those Breed Clubs to their members. Anyone mating a Lafora Affected dog will be introducing the mutation into their country’s population and there’s a 1 in 4 chance that anyone breeding from a Carrier will be doing the same.

DNA testing for the cord1 PRA mutation in all three varieties of Miniature Dachshund has been widely adopted by UK breeders and the mutation frequency is much lower than with Lafora disease, but nevertheless we do also risk exporting this condition. Most overseas breeders will probably wish to have any dog they are importing clinically eye-tested via the KC/BVA/ISDS Scheme, which is able to pick up other inherited eye conditions such as Distichiasis, Ectropion and Entropion.

Those people importing dogs to the UK would be well-advised to ask about health tests that are routinely carried out in the dog’s home country. For example, many of the Scandinavian countries conduct X-ray screening for IVDD calcifications. Any Wire or Mini Wire imported from Scandinavia should also be DNA tested for the NPHP4 form of Day Blindness PRA. A research report published in 2013 made us aware that there are high mutation frequencies of Brittle Bone Disease in Standard Dachshunds from some European countries. A DNA test is available and Wires appear to be most affected.

Anyone who sends dogs overseas has a moral responsibility to ensure that the new owners are made aware of any potential inherited problems that might emerge in future litters from that dog, whatever breed or variety. There are identical responsibilities if you are importing a dog. If you are in this situation, you can contact the Dachshund Breed Council’s Health Sub-committee for confidential advice on the potential risks and available screening tests.