# linebreeding?



## daisymay (Feb 13, 2017)

so, i dont have alot of experience with linebreeding. i was looking at this ladies herd and was interested in a kid.
okay so there are two goats that are seen alot in the pedigrees. i used the normal pegree paper and the sire i used the plan pedigree 
ddsds,dsds,dsddd 
and the sdds,sds,sddds are the same. 
so its either the same doe or her son.
The good thing is my boys are preety much an outcross on this kid so that is good but.... what do you all think of the inbreeding?


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## Feira426 (Dec 11, 2019)

You lost me with all the d’s and s’s, but following because I also want to know people’s thoughts and experiences with line breeding. ☺


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## daisymay (Feb 13, 2017)

ddsds, is dams dam sires dams sire- dont really know how to make that make more sense.


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## KY Goat Girl (12 mo ago)

I got it. The only experience I’ve had with line/inbreeding are accidents. But they haven’t been bad. Both times we’ve had jail breaks with the bucks, Sukey was bred to a relative. The first time was her dad and the last time was her half brother. Neither one produced bad kids. We’ve also had a few other does accidentally be bred by a relative but non of them produced bad kids either. This next breeding season I’m gonna be linebreeding on purpose, two aunts to their nephew. I’m interested to see what I get. 

I will admit you lost me with all the d’s and s’s so somebody else will have to give you their better opinions.


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## littleheathens (Apr 27, 2019)

I was just digging around here and elsewhere yesterday looking for the same thing. (I think @HoosierShadow posted about 10 years ago- funny to see who was doing what when!- a helpful post). A couple of things I took away are when breeding relatives if successful it is referred to as linebreeding, if it's not then people call it inbreeding. It should be done for positive outcomes and intentionally, ideally. Also, sire/daughter or dam/son are safer crosses than breeding siblings since they share so much genetic material. Many people (in that thread) had some positive experiences with those breedings. You're likely to emphasize the good traits, as well as the bad traits (so start with good genetics is the lesson there).

I bred a mini Nubian to her sire this year. I wanted the smaller statured buck (ND) for her FF and he's given us such nice kids. She was having none of our other buck so she helped make the final decision. I'm not worried at all about the kids- I think they'll be GREAT but I have some concern over the marketability because some buyers may be hesitant. Great breeders do it often though, in various species, and wild animals too.


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## Jubillee (Dec 22, 2017)

It's kind of hard to see like that, easier to see on pedigrees. Most of those look fairly far back. Linebreeding helps cement good traits but can also exacerbate bad ones. I do and will line breed but cull heavy. I personally don't care for super heavy linebreeding as you can get into the territory of having issues with health or vigor.


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## JML Farms (Jan 1, 2021)

littleheathens said:


> Also, sire/daughter or dam/son are safer crosses than breeding siblings since they share so much genetic material


I agree. Never breed siblings. I also might add that it’s probably not a good idea to line breed more than three or four generations deep. Personally we line breed rabbits and have found that after three or four generations we have more “genetic issues” with the offspring. Good idea to introduce new desirable genetics. Other may have had different experiences.


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## Jessica84 (Oct 27, 2011)

100% what Jubillee said!
If you break it down to fractions, being that far back it probably won’t look as close as what it does on paper. So the results of a offspring is 50/50 sire and dam. That’s 50% of any good or bad traits showing up from each side. That also means 25/25/25/25 of the grandparents. So if you keep breaking that down and adding it up that will give you a idea of how much concentrated that animal(s) will be in your breeding. 
Easy example:
Bob and Jill produce Mary. That’s 50/50 Bob and Jill. Mary bred back to Bob that is 25% Jill and 75% Bob with all his traits. 
I hope I didn’t confuse the crap out of you lol I myself it j liked the animals and I think they would pair well with my bucks I would go for it


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## CountyLineAcres (Jan 22, 2014)

Keep in mind that the inbreeding coefficient for sire/daughter or dam/son or full-siblings are both 25%. Technically, one is not more advantageous than the other.

Half-siblings would only be 12.5% which would be more ideal but that doesn’t guarantee a better outcome.

Also, inbreeding simply increases the homozygousity in a population. Which isn’t always a bad thing. However, it is recommended to outcross the outcome like you said.


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## Mike at Capra Vista (Nov 30, 2017)

JML Farms said:


> Personally we line breed rabbits and have found that after three or four generations we have more “genetic issues” with the offspring.


Would you mind listing some of the “genetic issues” you encountered? I'd be interested.


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## JML Farms (Jan 1, 2021)

Mike at Capra Vista said:


> Would you mind listing some of the “genetic issues” you encountered? I'd be interested.


In particular with rabbits, I've experienced increased malocclusion with successive generations. I'm friends with another breeder who experienced hip dysplasia as well. Maybe just a coincidence, but when new genetics are introduced and bred to the existing rabbits, the issues disappear.


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## littleheathens (Apr 27, 2019)

CountyLineAcres said:


> Keep in mind that the inbreeding coefficient for sire/daughter or dam/son or full-siblings are both 25%. Technically, one is not more advantageous than the other.
> 
> Half-siblings would only be 12.5% which would be more ideal but that doesn’t guarantee a better outcome.
> 
> Also, inbreeding simply increases the homozygousity in a population. Which isn’t always a bad thing. However, it is recommended to outcross the outcome like you said.


You're right! Thanks for pointing that out. Thinking superficially, it made sense that full siblings share more but I hadn't calculated it. I wonder if it's just a common misunderstanding, or if there's some other reason to prefer parent/offspring over sibling breedings.


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## CountyLineAcres (Jan 22, 2014)

littleheathens said:


> You're right! Thanks for pointing that out. Thinking superficially, it made sense that full siblings share more but I hadn't calculated it. I wonder if it's just a common misunderstanding, or if there's some other reason to prefer parent/offspring over sibling breedings.


Honestly, I wouldn’t be surprised if it’s just a weird wives tale.  I honestly thought the same thing for a long time because that’s what everyone says. However, when I was calculating the COI I was like… wait a darn minute lol. I think it could be a weird case of telephone.

For example, I remember when I first started and I was told countless times that a buck has more genetic influence on a single litter of kids. It is likely a misinterpretation of a study of mice in 2015. The study showed that the traits a kid inherits from their father are statistically more likely to be “active”. However, both parents still contribute 50% of their genetic material to each offspring (with the dam contributing a smidge more to their sons because of mitochondrial DNA). I think some things just get lost in translation.

I tried to see if there was any scientific evidence of certain combinations with the same COI being worse than the other, and I have found nothing. I’ll have to keep looking!


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## Cedarwinds Farm (Dec 2, 2019)

Here's and older thread that touches on these subjects. I thought it was an interesting read. 








Inbreeding, Culling, and Goals


Several discussions lately have touched on these subjects. I would be happy to share the ideal that I am looking for, the parameters that justify culling, and what I'm doing with inbreeding of certain individuals. Some of this will take a while to type out.




www.thegoatspot.net


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## Feira426 (Dec 11, 2019)

I don’t know much about this at all, but...
Hypothetically (I think this would be VERY rare, but it’s just an extreme example), couldn’t you have full siblings that share absolutely no DNA, and also siblings that have identical DNA? Like, doesn’t it just depend on which genes they happen to get from mom and dad?

Like, say, mom passed her blue eye gene to one kid, but her brown eye gene to another kid. And maybe a black base color gene to one, and gold to the other. If two full siblings just happened to get a different gene from every possible pair of genes... those siblings would be basically, genetically, unrelated. Right?

Or also the opposite could happen.

Again, might be wrong. Just wondering out loud. Feel free to correct me!!


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## KY Goat Girl (12 mo ago)

That sounds very interesting. Never thought of that. Excited to see what people have to say about that.


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## toth boer goats (Jul 20, 2008)

Really good advice.


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## CountyLineAcres (Jan 22, 2014)

Feira426 said:


> I don’t know much about this at all, but...
> Hypothetically (I think this would be VERY rare, but it’s just an extreme example), couldn’t you have full siblings that share absolutely no DNA, and also siblings that have identical DNA? Like, doesn’t it just depend on which genes they happen to get from mom and dad?
> 
> Like, say, mom passed her blue eye gene to one kid, but her brown eye gene to another kid. And maybe a black base color gene to one, and gold to the other. If two full siblings just happened to get a different gene from every possible pair of genes... those siblings would be basically, genetically, unrelated. Right?
> ...


Yes! Exactly right. Those chances are just so minuscule, you nor I will likely ever see it in our lifetime. Which is so interesting when you think about it.

Full-siblings share approximately 50% of their DNA on average due to recombination. However, it can vary, like you said, depending on what genes you inherit. However, studies have shown that the variance is most always between approx. 40% and 60%. 

Since it’s essentially on a bell curve, the chance to have two non-identical siblings be 0% or 100% related is infinitely small. You’d actually have a better chance of being struck by lightning twice in your lifetime. Which I honestly think is pretty cool! 

The exception to all of this is if you had an identical twin, you share roughly 100% of your DNA, so your COI goes up to 50%.


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## KY Goat Girl (12 mo ago)

This is a very interesting thread. I’m thoroughly enjoying reading through it.


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## Feira426 (Dec 11, 2019)

Me too!


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## toth boer goats (Jul 20, 2008)

👍😉


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