Thoughts on inbreeding snakes.........

[JonD]

I just wanted to start a discussion on everyone's thoughts, about inbreeding snakes, either for proving new morphs, or, just plain breeding. Do you think that down the road, certain species will run into health problems, etc., just like some breeds of dogs. I have read posts for and against it, and personally I think that eventually problems will arise, what do you all think?:)

[UpscaleBoas]

jon d.....interesting post....you'll get lots of diff opinions....

me...i believe that in breeding is common to expediate the proving of new morphs...it can be done without but you could lose years off your compeditors.....once it has been proven though i think people should do all they can to avoid it...

with habitats being destroyed and more and more animals facing extinction i belive that we need to do all we can to ensure that there is vast .. healthy genetic stock to preserve these animals

somes tag line at snakes is preservation through captive propagation...or something close....he's right.

[JonD]

That is what I was thinking about, take for example, the Hog island Boa. They are extinct in the wild, now people that breed em are only most often then not, to get the best colors possible. Over generations, they won't be anything like the ones that were first taken as wildcaught.

[Linds]

People are always quick to jump to the conclusion that inbreeding is the cause of heath problems and deformaties. I would be more inclined to lean towards husbandry than I would to inbreeding. In captivity everything is changed. Different bacterial exposure, reduced exposure to parasites as well as no natural parasite control factors, reduced excercise, as well as no matter how hard we try, we can never come close to giving them the variety they feed on in the wild (with a few exceptions).
In the wild inbreeding is very natural. Adding new blood is actually more of a foreign incident. Especially with all the insular species. Locality specific animals are loaclity specific for a reason. They are all bred together and have done so for ions. As mentioned above, inbreeding has brought them to the level they stand at today.
For reptiles (ie-corns) that have a lot of morphs, they do seem to have a lot more abnormalities and the like. People often attribute this to inbreeding. However does anyone stop to think that perhaps these morph animals are genetically weak in the first place? Most morphs do not last more than a heartbeat in the wild. It is considered a defect.
For animals (ie- beardies) that started off with a relatively small population and have had little-to-no new blood added, abnormalities may also be quite high. Has anyone given any thought to the fact that since survival of the fittest has been taken away, many of the breeding specimens were not prime examples and combined with the small foundation population, increases the effect of poor blood.
Everyone is so quick to point the finger at inbreeding, but IMHO, there are a gazillion other possibilities that are being overlooked.

[ohh_kristina]

not this again :p

Do a search on the forums. This discussion has been had many times and there are great answers and debates in some of the threads. - Some people may not want to answer this thread because they've done it over and over again. :D

[Linds]

Originally posted by ohh_kristina
Some people may not want to answer this thread because they've done it over and over again. :D

LOL... that's why I went back and copy and pasted my last reply to one of these discussions instead of typing it all out again :p

[Siretsap]

If you look at some of the monitors, same species different localities, in my opinion this is caused by inbreeding.
Some species are isolated and small numbered. Thei inbreed and they are still around and don't have the problems we might think they would.
But then again, I have heard of snake being born with one eye due to inbreeding (in my opinion it's more of incubation temps) but who knows
Until there are studies that prove the pros and con's on it, I can't say it is ok and that it isn't.

[C.m.pyrrhus]

To me it depends on the species. As far as I am cocerned, a lot (most) of snakes in the wild breed with a close group of others, be it their uncles, sisters, aunts, grandmoms, cousins... etc etc. Some species of crotes and even Mtn Kings are even closer in relation to each other (moms,dads,sisters and brothers), and have been doing so for generations and eons. Hard to say that they have been impacted in any bad way by their natural ways.

As far as breeding in 'pet trade' herps, they are far from a conservative stand point, as they have no big ties to their ancestors. You cannot really say that some of the corns out there are even closely related to wild populations, same with some boids and other common herps. They have been breed to everything and anything to pass on a genitic design rather than bred to keep a species as whole.....if that makes sence.lol.

I do not think inbreeding is as bad as it is for mammals as it is for herps. Most do not have such a large home range as lets say mountain lions. Inbreeding in mtn. lions would prove to be fatal, as for herps it is just a way of life. Take the Mtn Kings. They live their lifes in small rocky outcroppings, and usually stick to one area their whole life. They do not venture out to find new bloodlines to create 'better' offspring. Their mates are close family members, usually not far from them or even in the same outcropping of rocks. Even same clutch siblings. They do not depend on new blood to make a better gentic animal, it simply is not needed nor does it impact them in a bad way. As for herps with larger home ranges, they do mate within a larger group. Herps with larger clutches and home ranges will also meet mates that are spaced further genitically, making it a wider bloodline, but still I see no big correlation with inbreeding in bad ways with them either. Just my opinion.....

[ChokeOnSmoke]

I'm not sure where I stand. I wish I knew some more about genetics. You reffered to dogs having genetic health problems. I was wondering how do dog genetics compare to reptiles? It maybe a dumb question just curious.
I think the reason most morphs dont last a heart beat in the wild is one, they are mostly recessive traits so your chances of coming across one are very low. Two, morphs are different colors or patterns and therefore are not camouflaged like they have evolved to be. Albinoism is one of the more common(I think anyway). It would be much easier to spot a bright orange/yellow/white snake than a drab brown yellow orange snake. Then take anery corns which is a morph that are not bright but darker colored, they appear in the wild naturally so I dont think they are genetically weak in the slightest.

[chas*e]

AAAuuugh not this again....lol

[Jeff Hathaway]

Inbreeding, in itself, is not bad. It simply makes certain alleles or 'traits' more likely to occur. This can be as simple as amelanism, or a tendency towards small size, or a defect which causes some problem. Over the long haul, inbreeding is potentially a serious issue, especially (as Linds pointed out) for species which were bottlenecked at the beginning due to small founder populations. However, recent research into habitat fragmentation has shown that it does not take very much 'new blood' to reduce the likelihood of problems. For example- say a highway divides a small group from a population, and virtually all individuals trying to cross the highway are killed. Will the small group eventually suffer from inbreeding depression? As long as at least a few individuals cross successfully every few years, apparently things should be fine. I wish I could remember the reference for this, but maybe someone else will know it.

As for comparing dogs with corn snakes, dogs are way more messed up, since humans have been breeding them for many more generations. So far, all we really have with corns are colour and pattern mutations- imagine a great dane equivalent corn that grows to 12' long, a chihuahua eq. that never exceeds 8", a 'wrinkled scaled' morph (the pug), and you get the idea! But, it is theoretically possible that we could see similar problems eventually in snakes as occur in dogs (i.e. hip dysplasia), so why not avoid inbreeding when you can?

"They do not depend on new blood to make a better gentic animal, it simply is not needed nor does it impact them in a bad way" Actually, nothing depends completely on new 'blood'; random mutations can (though it is rare) improve the fitness of offspring as well. However, you cannot say that new genetic material isn't needed nor impacts them. How can you tell? Perhaps a new virus will wipe out a whole population next year that would have survived if it had outbred with another. Perhaps a recessive mutation occurred in this year's offspring that will begin to show itself a few generations down the line as they mate with each other (like melanism on an island) and this mutation will ultimately kill them off. There is no way to forecast with any surety what a species need genetically, nor what impacts they will or won't suffer.

Jeff Hathaway
Sciensational Sssnakes!!

[Oliverian]

LOL... that's why I went back and copy and pasted my last reply to one of these discussions instead of typing it all out again I thought that post looked familiar, Linds! :)

Jeff, I'm thinking along the same lines you are. I'm not sure if it's right, but I think it makes for a pretty good theory.
[quote]we could see similar problems eventually in snakes as occur in dogs (i.e. hip dysplasia)] Yes, mabye one day we will have legged snakes, and then they may be able to get hip problems. ;) Just buggin you man. I see your point.
-TammyR

[Removed_2815]

This will likely not be a problem with many reptiles that live their life within a limited area.
Many snakes spend their whole lives within ranges as small as a few square feet and these animals are already the result of years of inbreeding. The reason we are not currently seeing inbreeding depression in these animals is because the deleterious recessive genes have been "weeded out" thousands of years ago. In this case there really is no heterozygote advantage; however, in the wild, this low genetic diversity would not allow the animal to adapt to any disturbance and could prove to be detrimental. Obviously, in captivity this is not an issue.
I suppose problems may arise from inbreeding snake species that are highly genetically variable, in that genetic mixis takes place over great distances and populations are constantly introduced to novel genetic complements. Inbreeding these animals may lead to inbreeding depression because there are plenty of deleterious recessive genes that will be expressed in the homozygotes.
So, I suppose it depends on the animal, but as I had mentioned, snakes can get away with this as every species is generally the product of years of inbreeding in the wild anyway.
Cheers,
RMB

disclaimer: I certainly don't condone inbreeding in captivity when there is so much genetic stock out there to begin with, especially when were talking about the captive reptile industry.

[Removed_2815]

Originally posted by Oliverian
Yes, mabye one day we will have legged snakes
Already have plenty of them, Boidae have vestigal pelvic girdles, essentially, legs.... Granted they don't exactly utilize the spurs for locomotion.
Cheers,
RMB

[jim mcallister]

Just want to say as a 1st time reader on this subject.......wow their is a lot to think about here...... some good points from everyone!!

[Jeff Hathaway]

Hey Ryan,

I agree with you completely in that many reptiles live in small populations with restricted gene flow, so most problem genes have long ago died out (and possibly some neat animals with them...). However, there is always the possibility of random mutations which crop up and then become far more common due to inbreeding. Not likely an issue in the short term, or even within the span of our lives. Remember, dogs have been 'bred' by humans for thousands of years. So if we talk about the long term, say at least 50-100 generations, there *could* be problems. So if the goal is to ensure that species survive in their present form into the future, why not try to avoid inbreeding? It isn't that hard- just don't repeatedly breed parents to offspring, etc. On the other hand, if one's goal is to produce an amelanistic patternless dwarf morph, go right ahead, but don't pretend to anyone that 'conservation' is any part of what is going on!

Jeff Hathaway
Sciensational Sssnakes!!

[Removed_2815]

Hi Jeff,

I think we are of the same opinion, I don't know if you read the disclaimer in my post. Apparently it's not a bad thing in snakes, but I don't condone it if it's avoidable. Most of what I wrote came out in a discussion I had with a researcher who was here doing a seminar on E. obsoleta reproduction. Of course, random mutation is the driving force of evolution but comparing artificial selection of snakes to that of other animals might not be a good idea (as I think you pointed out also).
I suppose the fact is, inbreeding will likely not affect captive populations of snakes (at least in no way that could be directly related to inbreeding) but my mammalian view on inbreeding prevents me from practicing it in my own collection if it can be avoided.
Also, as I am sure you know, random mutation is a rare event and perhaps it is this probablity that we should be looking at when trying to quantify any possibility of problems associated with inbreeding. There is such a small chance that a random mutation will occur, coupled with the chance that the gene may not be deleterious (doesn't happen too often). Obviously, however, the best/quickest method for gene flow to occur in a population is through inbreeding.

Cheers,
R