I think a lot of that has to depend on the quality of the two goats you are breeding, two goats with the same fault should never be bred together, this holds the same for goats even not related. Line breeding intensifys good traits, but it also intensifys bad traits.
There was an artical in dairy goat journal last year on line breeding. It was really good, this is how they described a good line breeding, they described a good line breeding as one animal apearing in the pedigree some two to six generations back three times. So when laid out on paper it formed a triangle with that goats name.
There is a page on the ADGA website, where you can type in the potential sire number and potential dam number and it will calculate the top ten animals contributing to inbreeding and what the percentage is.
I like to keep a generation or even two in the least when line breeding. But thats my personal opinion. Some people will breed a doe back to her sire, half sister to half brother and so forth. I had a friend that bred a buck back to his dam she got a nice kid that did well in the ring as a kid, never did steller as a milker though, and a full sister that had three teats.
hope this helps and i didnt confuse you
Ditto what Beth said, it depends more upon the animals than it does the type of line breeding you are doing. I've done linebreeding a couple of times. Both of them were half brother half sister. In one case, I got two does, one doe was 'ok' and the other one was fantastic. As the 'ok' doe matured, she started showing greater body capacity, dairy character and a better topline than she did when she was younger. I've seen some really bad inbreeding(luckily I haven't done any myself) but you really have to know what you are doing.
When it works, its linebreeding, when it doesn't its inbreeding :wink:
Many people have different views on this topic. Personally, the main ones I wouldn't breed would be full brother/sister (same mom and dad) to each other or multi-related such as if I let my buck breed his mom (which I have done and got great kids) I wouldn't breed him to any doeling from the breeding because she would be his daughter and half sister.
That being said, I ran a poll here to get the same info you are looking for and didn't get much response, but of those that resonded, the majority said they only breed to non-related does, which is impractical for me as I am adding some of this years doelings to my small breeding herd and I have only 1 buck.
It is important to be sure you have good quality stock on both sides to breed out faults rather than breeding in faults.
Ok, well Ice and Noel ARE full brother and sister. (unless I'm mistaken - but I'm pretty sure of it). So now that I've learned a little more about line breeding - I won't be using them together.
My future plans for Noel will just have to be to breed her back to a reg. nd buck. Which will probably make for some FLY AWAY Airplane Ears ! But it's better than risking kids with major faults.
And I only like to have 3 bucks (no more) around - so I don't plan to get another mini nubian buck (other than Ice). So she'll just have to get bred to the nd buck I plan to get sometime this year (hopefully from Stacey).
So far - to date - all of my customers are looking for pet goats anyway, and a few just for milk. I haven't had any show driven customers anyhow.