Getting priorities straight: Risk assessment and decision-making in the improvement of inherited disorders in pedigree dogs

School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7AL, Northern Ireland, UK.
The Veterinary Journal (Impact Factor: 1.76). 08/2011; 189(2):147-54. DOI: 10.1016/j.tvjl.2011.06.012
Source: PubMed


The issue of inherited disorders in pedigree dogs is not a recent phenomenon and reports of suspected genetic defects associated with breeding practices date back to Charles Darwin's time. In recent years, much information on the array of inherited defects has been assimilated and the true extent of the problem has come to light. Historically, the direction of research funding in the field of canine genetic disease has been largely influenced by the potential transferability of findings to human medicine, economic benefit and importance of dogs for working purposes. More recently, the argument for a more canine welfare-orientated approach has been made, targeting research efforts at the alleviation of the most suffering in the greatest number of animals. A method of welfare risk assessment was initially 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. This article discusses how 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. A new risk assessment criterion, the Breed-Disorder Welfare Impact Score (BDWIS), which takes into account the proportion of life affected by a disorder, is introduced. A set of health and welfare goals is proposed and strategies for achieving these goals are highlighted, along with potential rate-determining factors at each step.

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    • "They also affect the evolution of genetic diversity within a given breed, as well as risks linked to the dissemination of genetic disorders. Some of those practices and their effects are linked to selection goals and breed standards (Higgins and Nicholas, 2008; Asher et al., 2009; Collins et al., 2011) but will not be considered further here since pedigree analyses mainly deal with loci that are not selected. However, the impact of some of these practices (e.g. "
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