Breeding for health in non pedigree dogs -- The Kennel Club

Breeding for health in non pedigree dogs (archived)

breeding_for_health_in_non_pedigree_dogs.pdf (Internal)

Outcrossing Programmes

What is an outcrossing programme?

An outcrossing programme aims to improve the genetic health and increase genetic diversity of a breed ( Breed A ) by introducing a new line or crossing it with another breed ( Breed B ) in a controlled and monitored manner. Once the health of the Breed A has been restored, it can then be bred back to purebred dogs to gradually dilute the other Breed B, and eventually breed it out completely.

Why would an outcrossing programme be needed?

One reason may be that an inherited disorder, caused by  gene mutation(s), may be highly prevalent in a breed and may threaten the population of the breed and its genetic diversity. To introduce the normal gene(s) back into the breed, it can be crossed with another breed with the intention to breed out the mutated gene and eventually eradicate it from the breed.

Here is an example:

An outcrossing breeding programme was carried out in the USA, aiming to introduce the low (or normal) uric acid gene from the Pointer breed into the Dalmatian breed through cross-breeding. The programme was put into place to replace the defective gene that affects uric acid metabolism, causing an increase in urinary uric acid, urinary stones and urinary tract obstruction.

Other reasons for using a crossbreeding programme are to improve the health of the breed in general, for example, improving conformation traits that may cause health problems, and improving general fitness and its benefits.  

Another reason may be that a breed has a very low effective population size, and is at risk of, or beginning to suffer effects of inbreeding depression – such as reduced litter sizes, fertility problems, or an increase in inherited diseases.

In any instance, it is of vital importance that population genetics expertise is sought to develop any outcrossing program. Identifying good  (breed) candidates for outcrossing, and ensuring there are sufficient numbers of animals to outcross to are just some of the aspects developing a successful program requires.

Are outcrossing programmes supported by the Kennel Club?

The Kennel Club supports outcrossing programmes that improve breed health and to preserve the genetic diversity of a breed. The Kennel Club will allow dogs with unknown ancestry to be introduced onto the Breed Register on a case by case basis. These dogs will have three asterisks next to its name on the register, which will be applied for three further generations to identify the fact that there is unknown or unregistered ancestry behind a dog.

Also see: -- The Kennel Club -- Breeding for health in non pedigreed dogs  in Downloads.

Description: A quick guide designed to provide some general information on health testing and schemes available for breeders of non pedigree dogs.

See the cross-breeding pedigree tree example in Breeding for health in non pedigree dogs -- demonstrates the need for health screening -- effective info graphic.

Articles provided by: Bonnie-Marie Abhayaratne,  Health and Breeder Research Assistant, The Kennel Club, www.thekennelclub.org.uk