Backyard Aquaponics
A place to discuss aquaponics

Research heavily suggests that male tilapia grow much faster and bigger. Obviously as a mouth brooder the female doesn't eat like she should when eggs and fry are in her mouth. I'm sure this contributes to the size and growth rates of females. If they are not allowed to fertilize the eggs i.e. putting mesh on the bottom so the males cannot drop their milt, would a female growth rate and size be close or equalivant to a male?


MM

Wow did I stump the forum??? I should get a prize for that. Will do my own study with female tilapia and post the results.

MM

Do it and get back to us with the results.

The fasting stage during the females egg holding does contribute to the size difference between male and female Tilapia however it is not the only factor. Even in mesh cage you can still expect size differences of up to 10%(usually closer to the 5% mark) between males and females.

Thanks BigZ and welcome

Nup - I just haven't been on

There's plenty of examples of this in the animal world, not just fish. It's called sexual dimorphism, and it can work either way. In redfin perch for example, the females are bigger than the males. The question as to why will come down to evolutionary factors.

It's one of the major reason why aquaculture researchers muck around with hormones alot, to generate monosex populations, thereby maximising growth.

To answer your question about unmating females having the same growth - no, that's not the contributing factor.

Male tilapia are faster growers and are more efficient feed converters than females. These are the primary considerations in commercial tilapia farming where all-male stock is used.