I have a couple fry batches from a super red bristlenose. Question is, if I wanted to start a pair for breeding, would inbreeding be a problem? If this was cows, goats, dogs, or even horses the answer is yes. But I am not completely sure with fish. Seems like guppies and tetras do it on their own. But I just lost my breeding pair to a crazy ammonia spike, it definitely hurt, but a had a grow out tank set up for guppies and plecos. So I was pondering that question to see if I had to go out and try to find a new male or female before I tried again. Thank you for any help you can provide.
Plecos breeding question.
- Thread starter Crashaxa
- Start date
fishguy1978
Legendary Member
So many of our fish that are CB come from repeat inbreeding. It works and eventually you will start to see genetic abnormalities but if you cull those you can produce good stock. Sell a bunch and then find a new male or female to add to the mix.
My current bristle nose pair came from @fishguy1978 and I know they are siblings. They have bred and I got a couple babies that seem to look normal. Most people probably would not think twice about this when it comes to the plecos, likely more an issue with some of the hardcore cichlid enthusiasts. Probably would not hurt to add some different genetic material to the mix in the future and at least purchase a different male or female from a different source.
That's not true. The problem with inbreeding is that it eventually reveals the consequences of deleterious recessive mutations. You can cull all you want to eliminate the affected individuals [which carry two copies of the deleterious mutant gene (actually, allele)], but most (66%) of the remaining, apparently unaffected fishes are still 'carriers' that contain one copy of the mutant gene (allele), and they will pass that gene on to 50% of their progeny. So you will never produce 'good stock' without the mutant gene (allele) by this route.
I applaud your concern, but in this case, I doubt that it makes much difference, because the damage has already been done. Let me explain.
Virtually all domesticated animals- cows, goats, dogs, horses, etc.- are highly inbred, the products of hundreds or even thousands of years of human intervention in their germ line. Given that, consanguineous matings in these species have significant risks of producing progeny that are homozygous for deleterious recessive mutations. This is not generally true for aquarium fishes, because as a group, they are much less highly inbred than domesticated animals. However, so-called line-bred strains of fishes, like the super red bristlenose, have been deliberately inbred to produce some 'desirable' trait, e. g. enhanced coloration, so they are significantly more inbred than most aquarium fishes. Moreover, given their relatively recent origin (in contrast to domesticated animals), one does not have to go back too many generations to find common ancestors for any given pair of fishes. That is, they are highly consanguineous. Choosing two fishes that are not demonstrably related is not going to reduce the coefficient of consanguinity all that much over picking two fishes randomly from your grow-out tank. So I wouldn't worry about it
It's a completely different situation if we're talking about wild-caught fishes, but that's another story
Good luck.