Originally Posted by Chiilaa
Line breeding and in breeding are not the same thing, for what it's worth.
In this case, you should be fine. The ONLY problem with in breeding is a simple genetics one. Say that Horse A is bred to Horse B, and foals Horse C. Horse C has 50% of each parent's genetic material. If Horse A had some recessive gene that caused something bad, for this example lets say "bunky leg syndrome", it has a 50% chance of passing that recessive gene on to Horse C. If Horse C, which has a 50% chance of carrying the Bunky Leg gene, is crossed to Horse A, who carries Bunky Leg but the owners don't realise, the resulting foal, Horse D, has a 50% chance to get a copy of Bunky Leg from Horse A, and a 50% chance of getting a copy from Horse C. Before you panic though, this does not equal a 100% chance to have the Bunky Leg gene. What this does mean, is that there is a 25% chance of having NO Bunky Leg, 50% chance of having one copy of the gene, and 25% chance of having TWO copies of the gene. Having two copies of Bunky Leg Syndrome gene will then cause Horse D to display the Bunky Leg traits.
So as you can see, in breeding like this just gives you a chance of doubling up on hidden recessive genes that the closely related horses might both be carrying. It does NOT give you mutant foals, foals with three heads, or foals that are always sickly.
Good job explaining. I'm really surprised at how many people think they can "pick out" an inbred animal. I've raised dogs for 20 or so years. I always have told people, when you think you're doubling up on the good, remember you're also doubling up on the bad.
Linebreeding and inbreeding should only be done by experienced breeders. Whether a horse or dog, I like to see the whole package (ex. A German Shepherd conformationally correct that can also work.)
People are always so quick to blame every fault be it behavioral or conformational on "ohhh it's inbred" without even seeing the pedigree when in fact it probably is not.
Edit to add, by experienced breeders, I mean someone who know the history of several horses/dogs whatever... in several generation...I am not referring to people who just pump out these animals "because they can."