In recent years, much information on the array of inherited defects in pedigree dogs has been assimilated and the true extent of the problem has come to light. Many breeds of dog have inherited disorders that may impair quality of life (QoL) to the extent that it is unkind to keep them alive. If we struggle to discern when this point is reached, why do we breed compromised, short-lived animals in the first place? If we struggle to judge when environmental conditions cause an unacceptable QoL, why not breed appropriately for modern environments? In breeding pedigree dogs, five major problems arise: (1) some breed standards and selection practices run counter to dog welfare; (2) insufficient selection pressure seems to be exerted on some traits that would improve animal well-being and produce dogs better suited to modern environments; (3) the incidence of certain inherited defects in some breeds is unacceptably high; (4) the dearth of registered animals of certain breeds in particular countries makes it extremely difficult for breeders to avoid mating close relatives; and (5) there may be financial disincentives for veterinarians to reduce the incidence of inherited diseases. Before we can judge when behavioural or morphological changes caused by selective breeding result in an unacceptable QoL, we have to know which are prevalent.
Beyond prevalence data, a method of welfare risk assessment has been developed as a means of objectively comparing, and thus setting priorities for, different welfare problems. The method has been applied to inherited disorders in pedigree dogs to investigate which disorders have the greatest welfare impact and which breeds are most affected. Work in this field has identified 396 inherited disorders in the top 50 most popular breeds in the UK. The results of welfare risk assessment for inherited disorders can be used to develop strategies for improving the health and welfare of dogs in the long term. For example, a new risk assessment criterion, the Breed-Disorder Welfare Impact Score (BDWIS), which takes into account the proportion of life affected by a disorder, has been introduced. A set of health and welfare goals has also been proposed along with strategies for achieving these goals and potential rate-determining factors at each step. Taken together with prevalence data, these indices offer the best means of strategizing a long-term approach to the problem of inherited disorders. They have been brought together in the recent INTERDOG proposal that combines prevalence, severity, duration and heritability data to ensure the best use of information resources and genetic technologies to deliver a brighter future for pedigree dogs.