Modern pedigree dogs in the United Kingdom Kennel Club: a journey through shifting population landscapes and demography

The limited genetic diversity in pedigree dog populations and the associated increased burden of inherited disease have led to calls for the development and implementation of effective population management strategies. Such strategies must be rooted in a thorough understanding of the genetic reserves and demographics of each population to be managed. Although numerous studies have examined the genetic diversity within various dog breeds, information on the structure of breeding populations and the characteristics of the dogs used for breeding is scarce. Furthermore, the few existing estimates typically represent the most common breeds, which may not be directly relevant for many of the numerically smaller breeds. We examined the demographic parameters of all 222 pedigree breeds recognised by The Kennel Club (KC) in the UK between 1990 and 2021. A meta-analysis was used to test whether all breeds can be represented by a single pedigree dog population, establish reference values for that population and determine the presence of significant variability between breeds. Overall, the KC-registered pedigree dog population is declining in size, and the percentage of dogs used in breeding is low. Dogs which have been successful in activities such as conformation shows and field trials have been popular in breeding. However, their use in breeding is in decline, partly in favour of imported dogs. The number of imported dogs, and their use in breeding have increased over time, particularly following amendments to the Pet Travel Scheme (PETS) in 2012. Across analyses, the within-breed estimates varied significantly, with the proportion of variation attributed to true variability between breeds exceeding 90% for the majority of estimates. The results of this study provide reference values which can be used to describe the demographics of the KC-registered pedigree dog population and its changes over the last three decades. However, the significantly high variability observed between breeds does not support the hypothesis of a single pedigree dog population and underlines that population management strategies must be tailored to the unique circumstances of each breed. The limited genetic diversity of pedigree dog populations has led to calls for the development and implementation of effective population management strategies, which must be rooted in a thorough understanding of the population to be managed. In this study, we used a meta-analysis to combine the results of population analyses across all 222 breeds recognised by The Kennel Club (KC) in the UK between 1990 and 2021. The objective was to test whether all breeds can be represented by a single pedigree dog population, establish reference values for that population and determine the presence of significant variability between breeds. We found that the overall population of KC-registered pedigree dogs in the UK declined in size between 1990 and 2021, particularly since 2010. Dogs that have been successful in activities such as conformation shows and field trials have been popular in breeding. However, their use in breeding is in decline, partly in favour of imported dogs. The number of imported dogs and their use in breeding have increased over time, particularly following amendments to the Pet Travel Scheme (PETS) in 2012. We detected significant differences between breeds for all demographic parameters studied here. As such, efficient management strategies for pedigree dog populations need to be tailored to the unique circumstances of each breed.