Comment to 'Bloodlines and Breeding'
  • 1) Animals don't always pass their qualities to their offpsring. To judge what kind of offspring a dog will produce, it is necessary to evaluate its relatives as well as the dog itself. If quantifiable data are available, the best way to do this is by calculating a Breeding Value. See for example the [url=http://siriusdog.com/articles/sv-zuchtwert-program.htm]SV Zuchtwert program[/url] 2) If linebreeding/inbreeding is used to form the bloodlines, then quite possibly the average vitality and health status of the breed will be lower than what it could be if proper selection was combined with inbreeding avoidance. Inbreeding does not narrow the gene pool, but it decreases heterozygosity thus making defective recessive genes express themselves. Usually bloodlines are established through the mating of relatives. Some breeders however prefer to mate phenotypically similar (like to like) dogs as the means to achieve a distinct phenotype. The latter is a safer way to create a bloodline. 3) See No1 4) Not per se, but using inbreeding to establish bloodlines, small numbers of founders, closed studbooks and the overuse of popular sires have led to inbreeding depression. The proof is in the studies that show that mixed breed dogs live longer and have fewer health problems than purebred dogs.