Just wondering ho often you can breeder sib x sib. then their offspring(sib x sib) together?

Just considering working on a poss supersalmon poss codominant stripe project?

Breeding direct siblings should be avoided. Siblings have both parents in common, so will share a lot of the same genes. People do it to prove things out sometimes, but there really ain't a good reason for doing it other then that. Breeding an offspring back to mom or dad, whichever has the desired trait, is a little bit safer. But both would require the offspring from such a pairing to be outcrossed in order to maintain gene diversity and health. If the albino gene is in the equation, it should be avoided at all costs.

That's my opinion.

Now for another opinion I heard voiced once that sorta makes sense. Using the Hog Island Boa as an example...It's possible, maybe even likely, that the whole islands population was started by a lone gravid female washing up on the shore. If this is the case, or even if it was a lone male and female that landed themselves there, that would make the islands entire population related directly to each other, except for the 2 founders. Haven't heard of many Hog Island Boa with any defects that are obvious, so this may lend some evidence to it not being such a bad thing.


As for how many times, well that's a hard thing to put a number to. You want to keep your genes diverse, or eventually you are bound to run into problems. Sickly critters, deformities, low viable offspring counts and high slugs just to name a few.

Dating a first cousin or even a sister probably a bad move

Dating a third or fourth cousin probably not so bad....

Really unless you are shooting for a particular gene I wouldn't do it, even if you isolate and bring out the gene (mutation) you run the risk of creating something bad from the other stuff you don't see in that mutation....alot more hidden behind the color or pattern in them like bad immune systems, maybe bad livers or kidneys, etc...you have to be willing to deal with the consequences of your breedings.

If you have 2 perfectly normal animals with no mutations and you just want more there is probably nothing wrong with it but then the question would be why with the availability of animals, trade off your normals for more normals and decrease the possibility of bad things.

The truth of the matter is even if you buy your breeders from different people, they may still have a lot of DNA in common. Most of your "pure" Local specific animals contain the same DNA and have for possibly hudreds of generations. That is why certain mutations happen in the wild, such as Hypos or amels and certain dominant pattern traits, Though normally they would not survive, nowadays a native comes along and picks it up and calls their contact here in the states and the next thing you know you have a "new" visual Morph imported into the U.S. that very well may be the result of inbreeding in the wild. the truth is, we do not know how many babys are born with defects out of a clutch,( in the wild) because there is no data, the research has not been done. In my opinion if there were lets say retics that came in 15 yrs ago. If they were all collected within the same region or area dont you think that theres at least a 60-70% chance that most of them are related. And as far as breeding in captivity most people would not want to say how many defective babys they have frozen down over the years.But im sure the Numbers are way up there.
And there were only 15 adult Honduran milksnakes ( all collected in the same area in the wild) imported into th U.S. and ALL the Hodurans you see now are from those same 15 adults. Thats 12 yrs worth of inbreeding no matter who your breeders are from.....just food for thought...........

Most people would like to think that there animals are not related, but unless you import them yourself ( and even then i wouldnt swear on it) they are possibly genetically related . The only way to truly tell is with a DNA test, and how many of us are going to cough up the change for that???


If any snake on the market today has the best chance of not being at least 25-50% related to its mate it would have to be the Ball Python, simply because of the amount of them that are imported every year. Must be well over 20,000 a year, that at least gives them a better chance at diversity.....

Breeding direct siblings should be avoided. Siblings have both parents in common, so will share a lot of the same genes. People do it to prove things out sometimes, but there really ain't a good reason for doing it other then that. Breeding an offspring back to mom or dad, whichever has the desired trait, is a little bit safer. But both would require the offspring from such a pairing to be outcrossed in order to maintain gene diversity and health. If the albino gene is in the equation, it should be avoided at all costs.

That's my opinion.

From a purely genetic standpoint, a sib x sib breeding has the exact same potential for inbreeding depression as a parent x offspring. Siblings share 50% of their genes with each other, while offspring share 50% of their genes with the parent. I've heard this belief that sib x sib is frowned upon, while parent x offspring isn't (rabbit breeders to reptile breeders), but from a genetic standpoint they are exactly the same.

I know a guy that does work with kingsnakes at my alma mater, and he said that it takes 7 generations of inbreeding to see inbreeding depression amongst colubrids. This should definitely be taken with a grain of salt as I don't think anyone would recommend doing anything close to 7 generations of inbreeding.

Boas, unlike kings, definitely do show a lot of genetic defects (missing eyes, etc) which would encourage breeders to outbreed as much as possible. It's a near constant subject in the boa community, while nobody seems to give a damn when it comes to ball pythons. Of course, genetic defects tend to be a rarity with ball pythons, unless it's specifically associated with a morph.

On the subject of island localities, while it's true that they may have evolved from a few founder specimens, over evolutionary time they've spent on the island, they should have lost a good portion of their deleterious genes.

An example, let's say they started off with two snakes that were both heterozygous for a lethal gene, so their offspring would be a quarter normal, 1/2 het, and 1/4 stillborn or dead before reproductive age. Over time, those that are heterozygous for the gene will produce less offspring then those that do not carry it at all (since a 1/4 of them will die), and eventually the percentage of the population carrying the lethal gene will become so small that it will either disappear or become very very rare.

It's clear that in the wild, natural selection will act in such a way that the beneficial genes will become more abundant while the less beneficial will become less abundant. In captivity, that's not exactly the case. There is a finite number of animals, and unless there is a lethal gene, even unfit animals will still survive to reproduce. Given these circumstances, it's best to avoid inbreeding whenever possible.

How much inbreeding is too much? Any more than is completely necessary.

I disagree. I do not think they are the same. Mom and dad both have the complete other halves of the chromosomes that they didn't pass on to the sibling in question. The chances of pairing up any deleterious genes becomes less going back to parents, because the chances each of the siblings having the genes is greater.

At least that's what my voices keep telling me.

I disagree. I do not think they are the same. Mom and dad both have the complete other halves of the chromosomes that they didn't pass on to the sibling in question. The chances of pairing up any deleterious genes becomes less going back to parents, because the chances each of the siblings having the genes is greater.

At least that's what my voices keep telling me.

It should still be the same. An offspring shares 1/2 of its total genome with each parent, and 1/2 with each of its siblings. In theory, siblings could share a greater percentage of it's genome with each other (which happens with identical twins). It's set in stone that each offspring gets 1/2 from each parent (1 egg, 1 sperm) but since the relatedness between siblings is due to which parts of each parent's genome it receives, it could vary from 0 to 100% (in theory). Actually, this makes sense for the sib x sib vs parent x offspring belief. In practice though, given the number of chromosomes and the amount of crossing over the occurs during meiosis, siblings share on average 50% of their genome with each other.

I think I've just argued both sides well enough, haha.

I still say impregnating your sister is a bad move...:lmao::lmao::lmao:

Depends where yer from. I heard some things about some places. :lmao::lmao:

Incest is best kept in the family they say.

Depends where yer from. I heard some things about some places. :lmao::lmao:

Incest is best kept in the family they say.

On second thought impregnating your mom is probably just as bad...:lmao:

But if your going to do it I say go for the sister...just seems like a better choice.

It appears that often, high dollar breeding plans are shaped (or flawed, imo) by economic factors thus the main consideration should be to disclose those strategies to the customer, when asked. The customer can then decide for him or herself whether the breeding plan is flawed, or acceptable.