Double recessive gene or sport?

[Ken Martin]

Hi, folks-

Are traits not found in the wild but found in aquariums, like balloon bodies and albinism, due to inbreeding for double recessive (rr) genes, or are they sports- rare and occasional genetic incidents? Do balloon mollies breed true, and what about albino mollies? What are the traits that can be bred into a line, and what traits can not be bred in with consistency, but will appear irregularly after being introduced?

What I am after: I would like to develop a line of healthy and vibrant extra-large orange creamcicle sailfin lyretails with natural body shapes (not balloon) and melanistic black spotting on the fin-tips. What would it take to get there, and what pitfalls must I avoid?

[Mustang Boy]

well the only way i can think of doing this is to start with a group of fish with the traits you wants and pair them off and as they multiply get rid of the fish that dont have the traits you are looking for and eventually you may be able to get what you want

[Fishguy2727]

Some traits are simple homozygous recessive traits (like albinism). But other are gradual traits (like less and less spots, brighter and brighter colors, or larger and larger size). All you can work with are the genes present. So the best plan would be to buy ones with those traits and select in the young the ones you like. Try and make sure hardiness is NEVER overlooked though. It is really impossible to select for hardiness AND anything else. Take a look at the article in my blog on why pure breeds are not ideal to get an idea of the things you need to be careful of. What usually happens in cases like this is that almost all of the offspring with the desired traits are not the hardiest. But the breeder selects the ones with the 'best' traits, overlooking hardiness/health. Then they have to take better care of them, which may not be an issue for them. But when any of these less hardy/healthy animals go to someone's tank who is not taking care of their tank at least as well the animals simply do not make it.