Dog Breeding Myths
Separating fact from fiction in the dog breeding world.
D. Caroline Coile, Ph.D. |
Posted: Tue Jun 1 00:00:00 PDT 2004
Page 1 of 2
They reproduce with amazing fecundity, thrive in all climates, and gather proponents wherever they go. Are they an amazing new dog breed? No, they're the myths of the dog breeding world and they're alive and well.
Myth: Breeding a flighty bitch will steady her temperament. If a bitch has a poor temperament, breeding is not going to improve it. It's only going to increase the risk of producing more dogs with flighty temperaments.
Myth: Breeding a slab-sided bitch will expand her ribcage. Again, if a bitch needs to be bred in order to develop some trait (which seems doubtful at best), then perhaps you should rethink your breeding program.
Myth: Any dog carrying an undesirable gene should be neutered. Every dog carries genes for undesirable traits, including some for health problems (it's been calculated each dog carries three to five such genes, on average). If they were all neutered there would be no more dogs. The secret is to avoid doubling up on such genes when breeding. As more DNA tests are developed for different genes in different breeds, this will become increasingly possible. If dogs identified as carriers are bred only to dogs tested clear of the gene, then the progeny should only be carriers and clears, not affecteds.
Myth: Repeat litters are never as good as the first ones. Proponents of this myth even offer a pseudo-scientific explanation of why this is so: "To avoid inbreeding in the population, nature makes sure the second litter isn't as good." How would nature accomplish this? According to the theory, the eggs will only allow inferior sperm to fertilize them if they (the eggs) recognize the sperm as coming from the same sire the bitch was bred to last time. So unless the bitch is bred to a different stud in between, the offspring will only be sired by the inferior sperm. By this logic, the second-born children of humans would all be inferior unless the mother had been fooling around with another man!
To set the record straight, no mechanism has ever been identified by which an animal or its eggs could recognize sperm as derived from the same male as the last time she was impregnated. Nor has any way for eggs to determine sperm carrying good dog-show traits versus bad dog-show traits ever been identified. True, repeat breedings often aren't as nice as first breedings. But that's more likely due to statistical chance.
Breeders are most likely to repeat breedings that have extraordinary puppies. The extraordinary qualities of these puppies depended in part on the random shuffle of genes in the eggs and sperm. The chance of getting such a fortuitous chance shuffle twice in a row is lower than the chance of getting an "average" shuffle. Thus, the litter quality will tend to regress toward the mean.
Page 1 | 2
Give us your opinion on Dog Breeding Myths
Login to get points for commenting or write your comment below
Get New Captcha