According to the latest study, hatchery and wild steelheads are genetically different. The main reason for these differences is the fact that hatchery steelheads have evolved in order to better accommodate themselves with living in captivity.
The study now answered steelhead hatcheries owners a problematic breeding question. Sometimes, in order to mix the genetic pool a little bit and avoid malformation caused by inbreeding, hatchery owners would bring wild steelheads to the reproduction pools. But they were not registering any success with the technique.
The only viable option for them to avoid inbreeding was to buy adult steelheads from other hatcheries. And, until now, the breeders could only guess the reasons for which the wild and the domesticated fish did not manage to produce any offspring.
Since hatchery and wild steelheads are genetically different, it would impossible for them to reproduce with each other. Especially since the researchers have found that there are more than 40 different genes in the hatchery-raised steelhead. This means that they are more different from one another than humans are from chimpanzees.
The main reason for these astonishing genetic differences is captivity. The steelhead has the ability of passing genetic information to its offspring, this means that a wild representative of the species would pass on information about hunting, surviving and mating places, while the hatchery representative can only pass on reproductive information since hunting and evading predators are out of the question in a small tank where food literally falls from the sky.
A great number of the different genes also come from inbreeding. As in the case of every other animal, a long inbreeding process causes genetic malformations. That is why some steelheads have different colors or suddenly come in various shapes and sizes.
So if you ever wondered why the steelhead that you caught in your last family camping trip was so different from the one you bought from the fish market, you have your answer. Hatchery and wild steelheads are genetically different, so basically you were eating another fish entirely.
These genetic abnormities are normal when a fast-reproducing species like the steelhead is forced to adapt to new lifestyle conditions. So there is no reason to worry that hatchery fish will make you sick, or cause you to grow an extra thumb.
Hatchery and wild steelheads are genetically different because, for decades, they have been exposed to different environments. Hatchery steelheads were not forced to look for food or defend themselves from predators, but they did have to adapt to pellet food and tight tank conditions. This led the species to evolve into a more adapted type of steelheads. Just like humans do when they move to the big cities.
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