Please excuse my ignorance as I have only owned snakes as pets. When Ball pythons are bred are the babies then used to breed back to the parents once old enough? Do siblings get bred together? If so, does this cause the same issues that happen with mammals like dogs? The reason I ask is because I have seen ads for pairs from the same clutch with something like " clown project pair" with a 1.1 het clown that are brother and sister. I googled it but no straight answers.
5 Likes
I can’t answer your question because I am a pet owner only but I am looking forward to the answers you get from the breeders. I have wondered the same thing but never thought to ask.
And don’t apologize for your “ignorance”. Others here will not think of you that way! It’s a great question!!! 
3 Likes
@angelicajay the short answer is yes. To prove a trait you usually have a different looking snake breed that to a normal then see if any babies have that trait and breed it back to the parent to see if it is genetic. Breeders do this with morphs as well to get more of a certain morph, which is ok they don’t seem to have genetic inbreeding issues like other animals can. That being said a good breeder will always introduce fresh blood and not consistently inbreed them over and over, because that can make weaker snakes over time for sure.
7 Likes
Thank you, I didn’t want to come off as rude. Like if you ask a dog breeder " Are these puppies inbred?" that would be considered an insult.
2 Likes
Yes I understand what you mean. I suppose in this instance we are not comparing apples to apples. But it is interesting to know. Nature is amazing!
2 Likes
Thats crazy, maybe because they lay eggs? I wonder what the science is behind that. It would make an amazing genetics class.
3 Likes
Yes and no. Continuing inbreeding generation after generation will lead to issues with any animal. That’s where the skill level of the breeder comes into play. You make decisions and then make adjustments based on the results. The power of selection is amazing. You get what you select for, whether you meant to do it or not.
Inbreeding = pairing directly related animals (siblings, dam x son, etc)
Linebreeding = pairing directly or indirectly related animals. Typically no nuclear family pairings.
The conundrum with inbreeding and/or animals with a high level of homozygosity is this; take it too far and you’ll have deleterious genes come into play, but do the wrong outcross and deleterious genes come into play. And to make it more complicated: all the snakes in the hobby come from a limited number of locations, and in the wild snakes inbreed to some degree due to biological factors (they can’t cover a lot of ground without legs or wings).
In my process there is a lot of nuance (and possibly a little voodoo). I’m essentially trying to refine the animal through line breeding, while not trading off physical health, vigor, or structure.
In other species that are less produced (especially avains) if I consider a physically defective animal vital to the project, I take that animal and create a brand new control group with it, in an attempt to preserve whatever trait the animal carries and hopefully separate it from the deleterious genes that are expressing the defect. In ball pythons today, there is no reason to waste the energy trying to preserve traits in such a way. There are too many of them. When I do projects like this any species, none of the animals produced ever leave my care. If they do, they’re just being inserted back into the population at a net loss to the the genetic quality of the population.
That makes my next point critically important, absolutely do not breed defective animals. If you maintain a healthy, vigorous base, you can take line breeding projects a long way without ever causing a problem. If you see problems, back off, make different pairings. Whatever you do, select strictly and you’ll maintain a tight line.
4 Likes
But not all snakes lay eggs. Some produce live (I found that out the hard way! Lol!
lol that is true!
1 Like
Wow thank you for the insight! I was wondering if it would be the same for birds too and you included that in there.
1 Like
Luckily the ball python market right now is mostly about bringing in more/different morph genes, which means the incentives are not so much aligned to excessive inbreeding.
If the market put more value on breeding multi-genetic line bred traits then I think things would be different on the norm.
Like others have said, inbreeding does happen but usually not for more than a generation to get the homozygous forms. By then it’s generally smarter to cross out to incorporate different morphs into the project.
I also think we’ll see a slight reduction of inbreeding overall as genetic testing continues to more and more displace breeding as the means to prove hets in recessive projects.
5 Likes
See I told you that you would get your question answered! Imho, snake breeding, done correctly, is a science project creating amazing results. It’s understandable why some of the snakes here are priced in the thousands. Amazing!
1 Like
Historically a lot of experienced snake breeders have claimed a few generations of inbreeding isn’t a big deal. However, there are species with known limited captive diversity (NOT ball pythons where hundreds of thousands were brought from the wild for years) where I have heard of issues and even the use of inbreeding coefficient calculations to outbreed as much as possible.
I choose to error on the side of outbreeding as much as possible just in case. This last year I traded a three recessive gene male with another breeder working on the same project because I have lots of his sisters growing up. I think it was worth the extra effort on both our sides but don’t have evidence to prove it to anyone who doesn’t think it matters.
I was interested to hear that genetic testing may some day be available to rate inbreeding in snakes.
I hatched a female that might be parthenogenic this year and as such she should be homozygous for everything and have the highest inbreeding coefficient possible. So far she is doing well but I’ve heard parthenogenic ball pythons have been known to die young. I do have a test pending that could prove she is from retained sperm and not parthenogenesis so of course that is my hope. If she had a father he might have passed het clown to her but assuming that test comes back negative I still will not be sure if she is parthenogenic or retained sperm but have asked if a scientist would be able/willing to test further to see which.
4 Likes
It’s probably because there are many insulated populations of snakes. It’s true with boas that island populations are quite small gene pools, so evolution dictates being resistant to inbreeding issues. It also keeps the population small to some degree also, from what I understand.
2 Likes
I mean we already have genetic testing for recessive genes, hopefully locality info and inbreeding stuff is available. Tho for small population localities of certain species that will be interesting to say the least.
2 Likes