En utvärdering av avelsprogrammet mot kronisk hjärtklaffsdegeneration hos Cavalier King Charles spaniels :

Sammanfattning: Chronic valvular disease (CVD) is the most common cardiac disease in dogs, which account for 75% of all the cardiac cases. Cavalier King Charles spaniel (CKCS) is the most affected breed and it´s 13th times more likely that a CKCS, between the age of 7-10 years, will die or be euthanized for cardiac disease, compared with other breeds. The prevalence has been proven to bee independent of coat color and weight but highly dependent on age and gender in CKCS. In 2001 the Swedish Kennelclub and the Special club for cavalier King Charles spaniel created a breeding program against CVD in CKCS. In this program dogs are not allowed to breed until 4 years of age and have to have a heart auscultation without murmurs. If a breeding dog is under 4 years of age but its parents is over 4 years of age and have a heart auscultation without murmurs, it’s allowed to breed if it has a heart auscultation without murmurs and is over 2 years of age. This breeding program has so far not been evaluated and the effects have been unclear. The aim with this study is to study the prevalence of CVD in 6 years old CKCS born in 2001, the first year of the breeding program. The result will help evaluate the effects of the breeding program and show whether the prevalence of CVD in CKCS has decreased or not since 2001. The findings in this study can be used as a start of a discussion whether any changes are necessary in the breeding program or not. The results in this study shows that the prevalence of CVD in 6 years old CKCS is 52%. This shall be compared with the prevalence of 35,5% between 1985-1991. This finding can be explained to a certain degree by the fact that the investigated populations not match each other. But the conclusion must bee that the breeding program has had no detectable or significant effect on the prevalence of CVD in 6 years old CKCS. The reasons to these results are presumably many. One not neglectable is that the age when the dogs are allowed to breed was set to low, 4 years instead of 5 years for the males and 6 years for the bitches as initially suggested in earlier research at the Swedish University of Agricultural Sciences. As a limited proportion of dogs have developed a heart murmurs at 4 years of age, this might have led to that too few dogs were excluded from breeding, which, in turn, might have reduced the impact of the breeding scheme. Other possible reasons could be poor breeder compliance to the program, using of breeding dogs in other countries and import of breeding animals. To get a more certain picture of how the breeding program works over time a similar investigation to the present could be performed. This would allow comparisons between two comparable populations.