johnnymax wrote:Both types are full blooded Mozambique Tilapia (Oreochromis mossambicus)
Probably not. IMO, unlikely.
Gold/albino/leucistic mozambique have been around for a long time (maybe 50 years or longer?). I've had at least 2 distinct types. Purchased my first of these (what I would describe as the flourescent orange kind; very pretty) around 1977. I think these were predominantly Mozambique, but probably not pure. At least they had the right body shape and breeding males developed the bright white gill plate. Other kind(s) I've had, I couldn't even say that about them, though I think they were predominantly Mozambique.
It's been well known and common knowledge in the aquarium hobby that these kinds of Mozambique from the aquaculture trade are hybrid. They were developed primarily because they have a different color of flesh and are marketed as "seafood". Likely they would have been crossed with
Oreochromis niloticus because of it's superior growth rate or sometimes even with
O. aureus because it's more cold water tolerant. Of course there are many others in the genus that they can be crossed with, though some of the crosses produce predominantly male because they are more distantly related. And one of the reasons
O. mozambique is used in some crosses is because they are more salt water tolerant then most of the other Oreochromis species.
IMO, just based on your picture, the fish is suspect hybrid because of it's body shape, smaller mouth, and if it's a breeding male should have a bright white gill plate as that trait shouldn't be absent because of a lack of pigment. Older males should develop a huge mouth ( especially in comparison to
O. niloticus) that eventually can become duck-billed shape.
So in all likelihood, the most you could say about these kinds are they probably mostly
O. mozambique.
Crossed regular with gold/albino types. Seems to me it was a recessive gene (just like pink and regular cons). Don't recall too much about it, as I only bred them for a few generations. But the gold/albino does show up again as it is a recessive gene but I think is unlikely to mix.
As far as line breeding for a particular trait, it can be done for just about any trait. But it's going to take dozens and dozens of tanks to grow them out, and probably many decades to actually accomplish anything. Cold water tolerance is definitely a trait that has been looked at by researchers in Tilapia aquaculture but not something that really makes sense for the average aquarist.
O. mozambique is from southern Africa, so it is one of the least cold water tolerant. Just makes more sense crossing
O. aureus for a more cold water tolerant fish and focusing on that species to line breed for this trait
