Inbreeding Question

[Her Farmstead Rabbitry]

I have 2 bucks and my younger buck is the offspring of my older buck. I'm going to call the older buck, buck#1 and the younger buck, buck#2. My doe ( the mother of buck#2) has a litter with buck#1. My question is if I breed buck#2 to the doe ( his dam), can the 2 litters breed with each other or are they too inbred?

Buck#1+Doe=buck#2
Buck#1+Doe= litter
Buck#2+Doe=litter
Can the 2 litters breed?

Sorry for such the confusing question! If it doesn't make sense I can try to elaborate more!

 

[Alaska Satin]

I have 2 bucks and my younger buck is the offspring of my older buck. I'm going to call the older buck, buck#1 and the younger buck, buck#2. My doe ( the mother of buck#2) has a litter with buck#1. My question is if I breed buck#2 to the doe ( his dam), can the 2 litters breed with each other or are they too inbred?

Buck#1+Doe=buck#2
Buck#1+Doe= litter
Buck#2+Doe=litter
Can the 2 litters breed?

Sorry for such the confusing question! If it doesn't make sense I can try to elaborate more!

In my program, it would depend on whether buck #1 and doe #1 were related, and if so, how closely. You can do a fair amount of inbreeding without seeing bad results, unless there are undesirable recessives lurking in the genome. If that is the case, you'll know pretty directly. I have found that this can sometimes be a good way to root out those undesirable genes. It's no fun for the rabbits affected, of course, so I don't do it if I suspect there will be a problem, but when it pops out it can be helpful in eliminating problems like malocclusion, for example.

I have done similar crosses, and as long as you're not dealing with hidden problem genes, it can be a good way to set characteristics that you do want in your herd.

 

[ohiogoatgirl]

When it works, it's line breeding. When it doesn't work, it's inbreeding.

I don't have any problem breeding closely. Nature does it all the time. We have the benefit of making sure anything with negative traits is removed from the population.

I want to say there was a study done and the bred a pair. They took a buck and doe from the litter and bred them together. And repeated to see how long until inbreeding problems showed up. Off hand I think it was something like 12 or 15 generations of full sibling breeding before they said ok now we have x, y, z problems because of inbreeding.

If you aren't willing to cull animals then don't breed close. Breeding related animals doubles up the genes. If someone has negative traits hiding then they are more and more likely to show up every time you breed closer.
The benefit of this is that you can breed close and cull the animals that have the negative traits! You can be much more sure that the ones you keep are not carrying those things.

 

[Rabbit Warren Man]

When it works, it's line breeding. When it doesn't work, it's inbreeding.

I don't have any problem breeding closely. Nature does it all the time. We have the benefit of making sure anything with negative traits is removed from the population.

I want to say there was a study done and the bred a pair. They took a buck and doe from the litter and bred them together. And repeated to see how long until inbreeding problems showed up. Off hand I think it was something like 12 or 15 generations of full sibling breeding before they said ok now we have x, y, z problems because of inbreeding.

If you aren't willing to cull animals then don't breed close. Breeding related animals doubles up the genes. If someone has negative traits hiding then they are more and more likely to show up every time you breed closer.
The benefit of this is that you can breed close and cull the animals that have the negative traits! You can be much more sure that the ones you keep are not carrying those things.

Line breeding will preserve the traits you want. Out cropping you never know what unwanted traits you may get. Rabbit breeds are all closely related already anyway.

 

[tambayo]

If you want to find out if there are recessive genes that can cause problems, test breeding (so once and whole litter for the freezer) so close will likely tell you. If you want to breed this close because you can't get other breeding stock and want to continue this way you'll breed yourself into a corner sooner or later.
All the "but they are so closely related already arguments" don't hold water, then breeding any together would give genetic issues and then the whole species would be extinct already.
And seeing the issues that crop op much later in a closed studbook (friesian horse for example), breeding close concentrates issues and they smack you in the face when the genes involved are pretty much carried by 90% of the animals and offspring getting 2 becomes common (or they don't carry to term / become pregnant at all ).
I have issues with the "it is not a problem in animals / species X, just in humans¨. Looking closer you'll see all kinds of "that is normal" explanations for behaviour and health issues like bad mothers, small litters, kits dying, hormonal issues like no milk, coat problems, dying in heat, digestive complications (outside of homozygote broken and megacolon), that tell me something else. Ditto for bigger lifestock bred for production and resulting birthing issues.

 

[aolsz]

"Date of the first full-sib mating: April, 1964. Date of the 20th full-sib mating: June, 1981."
https://pubmed.ncbi.nlm.nih.gov/3732413/
That's 20 generations of brother - sister matings.

Labs do this so that they can produce animals that are identical for the purpose of experimentation. Another reason for producing intensively inbred lines is in order to boost production through heterosis -- the method that's used for corn and chickens.

 

[Rabbit Warren Man]

I have 2 bucks and my younger buck is the offspring of my older buck. I'm going to call the older buck, buck#1 and the younger buck, buck#2. My doe ( the mother of buck#2) has a litter with buck#1. My question is if I breed buck#2 to the doe ( his dam), can the 2 litters breed with each other or are they too inbred?

Buck#1+Doe=buck#2
Buck#1+Doe= litter
Buck#2+Doe=litter
Can the 2 litters breed?

Sorry for such the confusing question! If it doesn't make sense I can try to elaborate more!

https://www.lonemountaincattle.com/breeding-guide/technical-resources/linebreeding-and-inbreeding/

 

[Rabbit Warren Man]

I have 2 bucks and my younger buck is the offspring of my older buck. I'm going to call the older buck, buck#1 and the younger buck, buck#2. My doe ( the mother of buck#2) has a litter with buck#1. My question is if I breed buck#2 to the doe ( his dam), can the 2 litters breed with each other or are they too inbred?

Buck#1+Doe=buck#2
Buck#1+Doe= litter
Buck#2+Doe=litter
Can the 2 litters breed?

Sorry for such the confusing question! If it doesn't make sense I can try to elaborate more!

https://www.google.com/search?clien...ate=ive&vld=cid:9c189291,vid:bwtO3nSQGfk,st:0

 

[eco2pia]

"too inbred" is not a thing, @aolsz is absolutely right. The trick is don't (continue to) breed bad stock as alluded to by everyone else on this thread.

The point is no breeding is completely free of risk. The risk of inbreeding/linebreeding once or twice has been greatly overstated, at least for an animal you are willing to cull. The reason the risk has been so overstated is that if you are inbreeding something you cannot cull or which is only going to have one or two offspring in its lifespan, like for instance humans, elephants, whales, the result of "errors" is devastating.

In the case of negative recessives, with MASSIVE numbers (usually beyond the average backyard breeder for rabbits) you can even cull away from terrible stock eventually. I have done this in a lab setting with genetically engineered animals that had off-target undesirable traits. It took many, many, generations, and many, many, culls, but I got there by applying basic husbandry selection, and breeding huge numbers, after starting with a basic breeding trio.

In your case, the more expedient effort is to try it, as suggested by @tambayo, with the plan to cull the whole litter. Once you know how that turns out, if the kits are at least as good as mom and dad, if they have any problems, then you can decide if you need to purchase more foundation stock, or you are good to go with what you have.

 

[aolsz]

Breeding brother to sister or father to daughter and then getting rabbits with eight legs or three eyes is a myth. If with close breeding, some genes for lethality or feeble young do become apparent, those traits are perhaps deleterious as hidden recessives. Inbreeding serves to sift them out.

Even though there's no reason to fear inbreeding in the absolute, what are your goals? If it's to breed lots of rabbits that grow quickly, continuous outcrosses will work well. If instead you are aiming at producing rabbits for shows and/or a specific color, inbreeding is the way to achieve this. It makes a lot more sense to get even just a couple of what you're looking for instead of dozens that you don't want.

And if you're in an environment of some temperature extreme, inbreeding perhaps can be used to produce a line customized for your location.