Inbreeding depression and selective breeding?

[Stewart_Reptiles]

Regardless, there are spiders that do not have the wobble. Some people on this forum claim there are also some non-spiders that have the wobble from a spider parent. My point is that we can likely select against the wobble, if people steered away from breeding individuals with the wobble. When i get my first spider, it will probably be a long search.

Sadly it is a wishful thinking, Spider wobble, spin however people want to call it, they ALL do to a certain degree with some it is barely noticeable so much so that some people claim that their spider don't wobble, just like I have seen people saying "my spider doesn't wobble but every now and than it will tilt it's head", well that wobble.

There is just a various range of the wobble from hardly noticeable to severe.

Severe wobbler can through babies with a hardly noticeable wobble and vice versa, wobble can also increase or increase over time, during stressful situation etc

The only way not to contribute to the pollution in this case is not to breed spiders because it just cannot be bred out,

[Krynn]

Well lets say that it cannot be bred out of the spider lines, well how about reduced? If the wobble is worse in some than in others, how about breeding it to reduction?

People assume that since reduced wobble parents can produce offspring with a nasty wobble, that the trait cannot be selected for. Perhaps its a continuous trait. What do you guys think?

It would be really interesting to see a nice pedigree of spider BPs, with the degree of wobble for each individual...

[rabernet]

Well lets say that it cannot be bred out of the spider lines, well how about reduced? If the wobble is worse in some than in others, how about breeding it to reduction?

People assume that since reduced wobble parents can produce offspring with a nasty wobble, that the trait cannot be selected for. Perhaps its a continuous trait. What do you guys think?

It would be really interesting to see a nice pedigree of spider BPs, with the degree of wobble for each individual...

It is believed that the degree of wobble in spiders is a variable as the level of white in pieds. Just as low white pieds can throw low white, and vice versa, so goes the wobble with the spider. There's just no way to predict 100% the level of wobble you'll experience with trying to breed just low wobble animals. Many, many people have tried since the wobble can be so "taboo" to many people.

[RandyRemington]

I'm just going to keep it short and sweet:

I agree that there is not enough selective breeding in ball pythons these days.. however, for reasons unrelated to the spider wobble and caramel kinking.

Because it's been pretty much proven that these issues are directly related to the single trait, no amount of "selective breeding" will be able to eliminate these problems.

Way more succinct than I could ever hope to express my position. Basically I believe that inbreeding should be avoided for general health of the animals but I think the problems with spiders, caramels, and super cinnamon/black pastel are all part of the expression of the respective mutation and not separate genes that could be bred out or in the line. Maybe someone will get lucky outbreeding these and find a separate gene that compensates for the negative aspects of those mutations but then we'll need inbreeding to keep that 2nd gene in the project.

[loonunit]

I'm working with pieds and hoping to do some cool double recessive and recessive+super projects with them. Which happen to be the same cool projects everyone else is working on, and there's ALREADY a tendency to inbreed recessives. So yes, I'm worried about it --- I'm planning to deal with it by mixing lines (ie. Kahl pieds with Kobylka pieds, watching for people with new lines from Africa, etc.) and eventually by breeding multi-gene morphs back to imported normals to get some new genetics into the hets via outcrossing.

THAT SAID: I'm not seeing inbreeding depression in the majority of the morphs out there. I think we're seeing it in some boa morphs, but not in ball pythons. The spider wobble and caramel kink both seem resistant outcrossing or line crossing--especially the spider gene, which is a dominant gene, and one of the most outcrossed morphs out there. Yet every spider still has at least a little wobble? That says something pretty clear. And what it says is: the wobble is tied to the spider gene, and can't be easily pulled out with good breeding practices.

It could be lessened with line-breeding however--repeatedly selecting for spiders with low wobble, generation after generation. But that's quite a big project, and wouldn't pay out quickly or much, so we may not see it happen for a while.

[loonunit]

(I'm glad we're thinking about this, though. I don't think we've been thinking about it enough, particularly with regards to recessive morphs. And eventually it'll catch up to us, for reason already outlined in this thread.)

[loonunit]

It is believed that the degree of wobble in spiders is a variable as the level of white in pieds. Just as low white pieds can throw low white, and vice versa, so goes the wobble with the spider. There's just no way to predict 100% the level of wobble you'll experience with trying to breed just low wobble animals. Many, many people have tried since the wobble can be so "taboo" to many people.

No, you can line breed for a few generations and produce a pretty steadily high or low tendency in a given population of pieds. It just takes longer and is less easy to predict. I've spent an embarrassing amount of time staring at pieds on ks and fauna, and there are some definite lines with very distinct traits emerging.

[MoshBalls]

Mosh's balls: Hopefully ill remember this post once im done my final exams for this semester, that is a fascinating topic. I know that national geographic did an article a month or two ago (maybe thats what your link is about) about selective breeding experiments in (red?) foxes. They artificially selected for tame foxes in one population, and agressive mean dogs in another. They are trying to isolate some "domestication genes" in wild animals and they seem to be doing a pretty good job. The domestic population has become puppy dog tame, and the agressive one.. well... i dont think i would be wanting to be the one cleaning their cage

Yeah that is the one. It was amazing. As the generations went on the tails became curly and shorter, and they went from a dark gray to white, black and spotted. The domesticated ones breed for non aggression would let you pick them up and cuddle up against your neck while the aggressive one bit the scientist through the cage when she put her hand up to it.

I most bring dogs up because of the fact that inbreeding was very common in dogs when the new breeds (similar to morphs) where trying to be developed. currently we are just in the beginnings, and I believe there will be more negative recessive trait appear in the coming decades.

I am not sure why the spider gene is connected to the wobble. It would be a very interesting study. That as the ball python we all could conduct if we were honest about line breeding, which morphs show any symptoms and the extent to which the animals had a wobble. The problem is that since there could be a financial backfire for admiring to having an inferior genetic pool there is much incentive to being less than completely honest in observations.

In any case, I think the fact that we are all aware of issues involved and considering ways to avoid an increase in negative genes, we are not the breeders that we need to worry about.

[Krynn]

Like i mentioned before i agree that the wobble is linked to the spider and therefore not a result of inbreeding depression. I am curious why you guys think that kinking has nothing to do with inbreeding depression?

It seems to me that it could very well be a recessive deleterious allele. It tends to occur more often in certain highly inbred lines, and it is not linked to one specific color or pattern mutation (I have even seen kinked normals).

Im not trying to say that your assumptions are wrong, i just dont understand where they are coming from.

[cinderbird]

Like i mentioned before i agree that the wobble is linked to the spider and therefore not a result of inbreeding depression. I am curious why you guys think that kinking has nothing to do with inbreeding depression?

Because there are people working with hets and visuals from as many lines as they can find and they are still producing kinked animals. Het caramels are extremely out crossed, most people wont breed visual to visual, they'll do visual to het or het to het.