Breeding Restrictions Decrease the Prevalence of Myxomatous XXXX in Cavalier King Charles Spaniels over an 8- to 10-Year Period.

@entity235 @entity339 @entity3454 @entity19020
BACKGROUND: Cavalier King Charles Spaniels (CKCS) are predisposed to @entity19020 ( @entity19020 ). Studies have indicated a strong genetic background. OBJECTIVE: The aim of this study was to evaluate the effect of a breeding scheme involving auscultation and echocardiography. ANIMALS: In the Danish Kennel Club mandatory breeding scheme, 997 purebred CKCS were examined during the period 2002-2011. Each @entity235 was evaluated 1-4 times with a total of 1,380 examinations. METHODS: Auscultation and echocardiography were performed to evaluate @entity339 murmur severity and degree of @entity3454 ( @entity3454 ). The odds of having @entity339 murmur or @entity3454 > grade 1 in 2010-2011 compared to 2002-2003 were estimated using logistic regression analysis including age and sex as covariates. Odds were estimated for @entity235 that were products of the breeding scheme (defined as @entity235 with both parents approved by the breeding scheme before breeding) and non-products of the breeding scheme (defined as @entity235 with at least 1 parent with unknown cardiac status). RESULTS: In 2010-2011, the odds of having @entity339 murmur were 0.27 if @entity235 were a product of the breeding scheme compared with @entity235 in 2002-2003, reflecting a 73% decreased risk (P  <  .0001). If non-products of the breeding scheme examined in 2010-2011 were compared with @entity235 in 2002-2003, no difference in odds was found (P  =  .49). CONCLUSION AND CLINICAL IMPORTANCE: A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of @entity19020 over the 8- to 10-year period. Such a breeding scheme therefore is recommended for CKCS.
