Too closely related to breed?

[Mini Lop Mama]

I will try to explain this quick and simply.

I have full sibling pair, buck (Caspian) and a doe (Noel). I have a seperate doe (Veritas) that has been bred to Caspian. I am keeping a doe from that litter (Quinn).

Noel has been bred to different buck (Huckleberry). I am keeping a buck from that litter (Kenobi.)

My question is, would Quinn and Kenobi be too closely related to breed together? TIA.

 

[RabbitsOfTheCreek]

No
Line breeding is a thing and that's parent to kit

 

[jaxmarblebuns]

As long as the rabbits are healthy there will be no problem. the only parring that is advised against is litter mate/full siblings, even that you can get away with sometimes.

 

[arachyd]

With rabbits you breed closely related rabbits to double up on the good qualities. This also works with bad qualities. As long as your rabbits are healthy with no known genetic problems there's nothing wrong with giving it a try. If there is some hidden genetic flaw inbreeding can help expose it and reveal which rabbits you want to cull from your breeding program.

 

[ladysown]

as long as they complete each other and don't have any obvious genetic faults.. yes

 

[Willow Blue]

As long as the rabbits are healthy there will be no problem. the only parring that is advised against is litter mate/full siblings, even that you can get away with sometimes.

Why is that? I've heard that but don't know the explanation. I'd like to know the reasons you can't breed littermates but breeding to a parent is considered ok. One of my Doe's is the Buck's sister/littermate. The breeder told me that was ok to mate them.

 

[kusanar314]

Why is that? I've heard that but don't know the explanation. I'd like to know the reasons you can't breed littermates but breeding to a parent is considered ok. One of my Doe's is the Buck's sister/littermate. The breeder told me that was ok to mate them.

The reasoning is that it decreases the gene diversity.

I'm not going to use real genes since this isn't color anyway but just an example:
Doe a/b
Buck c/d

Kits can be a/c, a/d, b/c b/d

Lets randomly select the 1st and 3rd options then you have a, b, and c as options but you have lost d entirely in a kit to kit breeding. If you then breed one of those to the buck, you can get the d gene back, same if you chose the 2nd or 4th, you would lose c.

Since you can't see these genes, you kind of have to expect them to work out in the worst way possible and go from there.

 

[Willow Blue]

Does this matter if they are just being used for meat?

 

[RabbitsOfTheCreek]

Does this matter if they are just being used for meat?

Yes because it can cause the rabbits to suffer due to defects

 

[Willow Blue]

Yes because it can cause the rabbits to suffer due to defects

Oh so it can cause birth defects? I thought it was just a trait thing. The breeder I bought from didn't have any birth defects and she breeds them that way. Does that mean they aren't carriers of anything bad?

 

[judymac]

The reasoning is that it decreases the gene diversity.

For every rule there are a thousand people out there successfully breaking it, and some that had a bad outcome. I have had some very successful sibling matings when I had no other rabbits of that color group to breed to. It CAN intensify bad traits, it DOES reduce genetic diversity, but that is not always a bad thing. If a kit with a bad trait shows up, it tells you something you did not know previously, that your line carries that trait. That can be valuable information. If all of your kits look wonderful, fabulous! That also tells you something. Close breeding can work very well when you start with excellent stock (that doesn't necessarily mean purebred or pedigreed, but good, healthy stock with the traits you are looking for in your herd--mothering ability, growth rate, body type, color pattern, etc.) If you already have good stock, then reducing the diversity so the next generations looks like the parents, can be a very good thing. Linebred stock often takes on a distinctive "look", you can pick them out at a show.

The concern with close breeding is that the rabbits may have a hidden recessive trait, like teeth that do not meet properly and twist and curl, or split penis in bucks. Or, that they may have a conformation fault that it intensified, like being scrawny instead of muscular, having narrow hindquarters or hocks that turn in. Usually, you see no problems at all, and if you only keep the very best of the litter, with the traits you want to see in rabbits (be it a friendly temperament, a fast growth rate, meaty conformation, a certain color, etc.) you should be fine.

The mating you have suggested seems like a fine choice, especially if you are happy with the original littermate siblings that will be the grandparents to this future litter.

 

[kusanar314]

For every rule there are a thousand people out there successfully breaking it, and some that had a bad outcome. I have had some very successful sibling matings when I had no other rabbits of that color group to breed to. It CAN intensify bad traits, it DOES reduce genetic diversity, but that is not always a bad thing. If a kit with a bad trait shows up, it tells you something you did not know previously, that your line carries that trait. That can be valuable information. If all of your kits look wonderful, fabulous! That also tells you something. Close breeding can work very well when you start with excellent stock (that doesn't necessarily mean purebred or pedigreed, but good, healthy stock with the traits you are looking for in your herd--mothering ability, growth rate, body type, color pattern, etc.) If you already have good stock, then reducing the diversity so the next generations looks like the parents, can be a very good thing. Linebred stock often takes on a distinctive "look", you can pick them out at a show.

The concern with close breeding is that the rabbits may have a hidden recessive trait, like teeth that do not meet properly and twist and curl, or split penis in bucks. Or, that they may have a conformation fault that it intensified, like being scrawny instead of muscular, having narrow hindquarters or hocks that turn in. Usually, you see no problems at all, and if you only keep the very best of the litter, with the traits you want to see in rabbits (be it a friendly temperament, a fast growth rate, meaty conformation, a certain color, etc.) you should be fine.

The mating you have suggested seems like a fine choice, especially if you are happy with the original littermate siblings that will be the grandparents to this future litter.

I never said it was a BAD thing, just that it does reduce diversity and that's the reasoning on why father to daughter is seen as better than brother to sister.

 

[judymac]

I never said it was a BAD thing, just that it does reduce diversity and that's the reasoning on why father to daughter is seen as better than brother to sister.

I agree, and it was a great explanation as to why. Also, if the father is an exceptional specimen, breeding back to increase his genetics in the offspring would be advantageous.

 

[hotzcatz]

There's a bunny database/ pedigree program called 'Kintracks' which keeps track of the level of inbreeding. If you have limited genetics to work with, it's really handy to be able to keep track of the 'Coefficient of Inbreeding' or 'COI'.

 

[judymac]

There's a bunny database/ pedigree program called 'Kintracks' which keeps track of the level of inbreeding. If you have limited genetics to work with, it's really handy to be able to keep track of the 'Coefficient of Inbreeding' or 'COI'.

Excellent! I hadn't heard about the 'coefficient of inbreeding'. I did an internet search and found a dog pedigree site that had quite a few links for more information. It's for dogs originally, but the same genetic calculations are involved and I found several of the articles quite illuminating. Inbreeding Coefficient Calculator – BullyPedigrees.com

 

[Keag]

Excellent! I hadn't heard about the 'coefficient of inbreeding'. I did an internet search and found a dog pedigree site that had quite a few links for more information. It's for dogs originally, but the same genetic calculations are involved and I found several of the articles quite illuminating. Inbreeding Coefficient Calculator – BullyPedigrees.com

I will be as quick as possible on this subject. Different dog breeds (breeders) will have different ideas of the acceptable COI of their particular breed. I have To Poodles & 1 Standard Poodle. The Standard Poodle across the world are as closely related Genetically as half brother/half sister. UC Davis runs genetic diversity dog programs. So the more Standard Poodles involved the more data. No matter what the pedigree states & your COI the importance are the Poodles with genetic out layers those are the ones that will bring in "diversity". To put another way no matter what COI is spit out it tells only a partial story. Genetically they can be very closely related or genetically not related at all. I have 2 Toys that have the same male, grandsire to , sire to the other. If I was to breed them the paper COI would be semi high. But after getting them genetically tested they are "unrelated". It is fascinating.
Until rabbits start a "genetic" database then a pedigree is only a little bit useful but not the end all.

 

[Alaska Satin]

I never said it was a BAD thing, just that it does reduce diversity and that's the reasoning on why father to daughter is seen as better than brother to sister.

Regarding line breeding and sibling crosses: it's a statistical thing, a calculated risk. Crossing siblings does not necessarily entail reducing diversity, while parent/offspring mating always does.

As @Keag points out, the relationship between the breeding animals only tells part of the story. Sibling crosses are often discouraged as "reducing genetic diversity" but that is simply a statistical prediction, not a fact.

Except in very unusual cases, a parent shares exactly 50% of its genetic material with its offspring. However, siblings share between 0-100% of their genetic material; that means that siblings can share far less with each other than with their parents. Theoretically, one kit could get one half of each parent's genome, while another kit gets exactly the other half of each parent's genome, and if the parents themselves were unrelated, those particular siblings would be completely unrelated (genetically) as well. On the other hand, theoretically both kits could get exactly the same half of each parent's genome; these would effectively be identical twins.

On average, individuals have 50% of their genetic material in common with their siblings, but again, that is purely statistical, and siblings could be found to be "unrelated" if they have significantly less than 50% in common. So it could very well be the case that breeding a parent/offspring pair would reduce your diversity far more quickly than breeding certain siblings.

As implied by @judymac, reducing genetic diversity in regard to certain characteristics is actually a goal of selective breeding, as you are trying to "set" desirable qualities and eliminate undesirable ones.

 

[Willow Blue]

Regarding line breeding and sibling crosses: it's a statistical thing, a calculated risk. Crossing siblings does not necessarily entail reducing diversity, while parent/offspring mating always does.

As @Keag points out, the relationship between the breeding animals only tells part of the story. Sibling crosses are often discouraged as "reducing genetic diversity" but that is simply a statistical prediction, not a fact.

Except in very unusual cases, a parent shares exactly 50% of its genetic material with its offspring. However, siblings share between 0-100% of their genetic material; that means that siblings can share far less with each other than with their parents. Theoretically, one kit could get one half of each parent's genome, while another kit gets exactly the other half of each parent's genome, and if the parents themselves were unrelated, those particular siblings would be completely unrelated (genetically) as well. On the other hand, theoretically both kits could get exactly the same half of each parent's genome; these would effectively be identical twins.

On average, individuals have 50% of their genetic material in common with their siblings, but again, that is purely statistical, and siblings could be found to be "unrelated" if they have significantly less than 50% in common. So it could very well be the case that breeding a parent/offspring pair would reduce your diversity far more quickly than breeding certain siblings.

As implied by @judymac, reducing genetic diversity in regard to certain characteristics is actually a goal of selective breeding, as you are trying to "set" desirable qualities and eliminate undesirable ones.

Thanks very helpful!

 

[Sapphire16]

The majority, basically most serious breeders in line breed ie. father to daughter, son to mother, half brothers and sisters, grand parents to grand children etc. to preserve and magnify the best qualities of the breed. Siblings from the same litter are sometimes bred to, as noted above, identify or verify good or bad characteristics. I read that testing has proved it can take many generations of continual inbreeding of good stock to have defects show up or affect the mental state of the rabbits. Rabbits in the wild are heavily inbred. If your selling closely related kits as breeders, you may have to educate potential buyers who have the concerns you expressed. Excellent information provided above!!!

 

[tambayo]

Linebreeding/inbreeding is more a succesfull yes/no depends on term used thing. We see the problems in certain groups of people where marrying cousins is common and has been happening for generations on end. Or the even closer family ties in some royal houses where brother - sister, niece - uncle and so on happend for max 4-6 generations before the whole family pretty much imploded from health problems, infertility and so on.
But somehow it is not a problem in animals. How much of that is truth and how much is not a problem traits that are ignored because show quality animal goal creates tunnel vision?
I just care about having healthy animals with inate good mothering skills giving 3-5 kits (5 preferred, but largest here is 7 from rex dwarf doe that is 5 years old now, was proven 5 and this is her second litter of 7 from 2 different bucks) and friendly/low stress behaviour. Coatcolors are fun, but i don't breed siblings for it. Might have to breed father to daughter due to buck shortage, but that litter will be for the freezer.
I know of another meatrabbit breeder who bought breeding stock from "good" breeder, they turned out small litters and weird problems and she later found out they where multigenerations of same litter matings.
I also hear a lot of show breeders finding small litters normal (1-3 kits for dwarf breeds). And i know fertility issues go with inbreeding. So I keep having a hard time believing the "it is not a problem" claims. It is blatantly obvious in many dogbreeds that the breedstandard stands in the way of health and welfare and there we know how inbred (and genetically tested free of the whole alphabet of whatever) they are. And even the fully tested animals have health issues like foodallergies, skin problems and so on.
So what is breeders blindness and what is truely not an issue?