09-18-2011, 02:52 PM
I was curious about this female male issue so I sent communique to one of the foremost fisheries biology scientists on the west coast. His work for years was not only the study of fish but to certify the university studies done in all universities on the west coast, Alaska and Hawaii. I asked him if triploid causing heat or chemical treated eggs all became female.
The reply:
Hi Don,
As for you question, heat or pressure induced triploidy produces both male and female fish. The females are more desirable because they typically don't develop mature ovaries and therefor grow better than the males. The males develop abnormal testes and almost all of the sperm are nonfunctional. But this degree of sexual development takes energy, which slows the growth rate.
BTW, this process isn't a mutation since no genetic information is changes. The effects are brought about in by a change in gene dosage. Triploidy occurs in nature in less than 1% of wild fish. Many world records are likely big old triploid females. The only case that I know where this has been verified is the world record lake trout.
I hope this answers your question.
Dr. Lee Weber
[signature]
The reply:
Hi Don,
As for you question, heat or pressure induced triploidy produces both male and female fish. The females are more desirable because they typically don't develop mature ovaries and therefor grow better than the males. The males develop abnormal testes and almost all of the sperm are nonfunctional. But this degree of sexual development takes energy, which slows the growth rate.
BTW, this process isn't a mutation since no genetic information is changes. The effects are brought about in by a change in gene dosage. Triploidy occurs in nature in less than 1% of wild fish. Many world records are likely big old triploid females. The only case that I know where this has been verified is the world record lake trout.
I hope this answers your question.
Dr. Lee Weber
[signature]