Dear god, how inbred are these little bristle-nosed cuties?!

[knifegill]

I just realized how dysmorphic my long-finned albino female is. It's a pretty safe bet she's the offspring of a sibling pair of a sibling pair of a sibling pair. My male isn't too asymmetrical. If they breed and I cull the most deformed, can I return this lineage to its former glory or am I doomed to spawn crooked pleco after crooked pleco on down the line forever? Why can't people start insisting they NOT pair siblings generation after generation? Look at these poor deformed fish! Stop it!

Can I even find an unrelated fish to outcross or are they all their own grandpas one way or another?

http://www.youtube.com/watch?v=eYlJH81dSiw

 

[SCGeordie]

OK, no expert here but I think you're stuck with the frankenfish unless you can get some fresh genes. Maybe if you could trace the fish you have back to a particular breeder and then look for a different breeder in a different part of the country (as far apart as possible) you may get lucky and end up with distant cousins.

 

[gomezladdams]

Dont breed the crooked fish.If you are looking to breed plecos seek out some good stock to start with.Its not the inbreeding that causes the deformities,its the bad genes getting expressed because both parents have it. Your fish will pass on the bad genes even if the mate is unrelated and they arent expressed next generation,they will come out in later generations.

 

[komodo182]

Dont breed the crooked fish.If you are looking to breed plecos seek out some good stock to start with.Its not the inbreeding that causes the deformities,its the bad genes getting expressed because both parents have it. Your fish will pass on the bad genes even if the mate is unrelated and they arent expressed next generation,they will come out in later generations.

I don't know the genome of a pleco or anything like that

but there is something we maybe missing and I could be wrong here as well.

This is just basic genetics here so it may not apply, but something to think about.

Maybe, just maybe, these plecos are heterozygous for whatever is causing them to be crooked.
I don't know if (for simple reason we will call it the ) "crooked gene" is dominant or recessive. In this case, hopefully dominant, if it is recessive, then you have very little chance of having any luck.
If it is dominant and the plecos have heterozygous genes for it, then there is a 25% chance that the plecos we be normal again.

However, on another note, if you know these have been inbreed, don't breed them for immunological reasons. I am treating fish like humans here since I don't have enough knowledge of the immune system of a pleco, but if it follows the same pattern as mammals and amphibians, then there are MHC 1 and MHC 2 receptors that they get from your mother and father that (for simple terms) help fight off the bad guys that get in you. Normally you get different combos because your mother and father are not related. If you take that away, you will get some problems because there will be no combos.

Once again, I was treating fish like humans since we do not go into fish immune system at my university, just humans and mammals and some amphibians.

 

[kdrun76]

Dont breed the crooked fish.If you are looking to breed plecos seek out some good stock to start with.Its not the inbreeding that causes the deformities,its the bad genes getting expressed because both parents have it. Your fish will pass on the bad genes even if the mate is unrelated and they arent expressed next generation,they will come out in later generations.

This is exactly correct. Gomez has nailed it perfectly.

Inbred deformities are a result of recessive deleterious (bad) genes that normally don't get expressed (because they are recessive) but when paired up with another fish that shares the same recessive deformity, they get expressed.

By breeding a fish that you know is homozygous for this deleterious recessive trait there is a 100% chance that the bad gene will get passed along. The next time it gets paired with another fish carrying the gene it will be expressed.

Why not breed fish that don't carry the trait. They are at worst heterozygous for the trait (50% chance of passing on the trait) and at best are homozygous dominant and don't even carry the trait.

(Of course all of this is presuming the trait is inherited by simple Mendelian genetics with one gene per trait which BTW is highly unlikely.)

 

[knifegill]

I really haven't much recourse other than to cull the deformed and reestablish the symmetrical gene pool by selection. My Oscar will love the process, I'm sure.

I'm only going ahead with the spawning process because the male shows perfect symmetry and many if not all the offspring should also. I will only sell those offspring which show good vigor and low dysmorphia. Yes, the crookedness might express in future generations but responsible culling by future breeders ought to return this lineage to good form. Plus, her finnage is amazing.