in line breeding

[mtman]

i was talking to a old farmer he told me its ok for the bull to mate with one of his girls but its not ok for a bull ( brother ) to mate with one of the sisters is mthis true

[wr]

It's not nearly that simple. If you are line breeding, you had best know your genetics, what traits you desire and what traits you find undesirable, what you hope to acheive and be willing to eat your mistakes. Every time you line breed for a desirable trait, you must understand that you can make a minor flaw more pronounced.

[mtman]

well this is our neibor he has been doing this for about 30 years he has some of the best looking cows you want to see he bands all the bulls born right away

[wr]

I'm not totally disagreeing with you but if he's been doing it for that long, he's still culling his disapointments and he may not even realize what factors he's considering. We've been raising purebred cattle for about 15 years and my family for about 50 and there is more to line breeding than just the parameters he's given you. If he's banding all his bull calves, it sounds to me like he's bringing in outside bloodlines at least periodically. All I'm saying is that you can line breed but you should know what you desire and hope to acheive and when it works, it works well and if it fails, it fails miserably and anyone that tells you they have the magic formula for line breeding is not being totally honest because every breeding program has a few failures.

[tyusclan]

Practically every purebred breed of animal we have today came about as a result of linebreeding. In the hands a knowledgeable and experienced breeder it is a valuable tool. You have to have very clear breeding goals and be able to recognize the slightest fault in your stock and cull ruthlessly because linebreeding/inbreeding intensifies the poor traits as well as the good traits by limiting the gene pool. The closer you inbreed the more the traits are intensified.

wr is right; it's not nearly as simple as this guy led you to believe. Making the right brother/sister could be a good thing to do. Making the wrong father/daughter breeding could be a disaster.

[Shelly]

I agree with the above posters completely. Just wanted to add one thing about father/daughter vs brother/sister mating. Statistically it's basically the same thing. Father and daughter share 50% of the same genes. A brother and sister are considered 50% related also. In reality, it could be slightly more or less depending on which genes each inherited from each parent, but we use 50% as a best estimate of relatedness. If there has been linebreeding or inbreeding in the previous generations, things may get a bit more interesting.

You can count on getting decreased performance in an intensely linebred/inbred animal. This decrease should disappear in the next generation if an outcross mating is used. Linbreeding your stock can be a very rewarding experience and it can be devastating if a serious recessive problem is uncovered.