Alleni Crawfish Sexing..

[vancouver]

Here's the deal.. We have a female alleni that has had 2 broods so far.. All the fry have turned out to be females..

She has another brood going right now.. The eggs just hatched, and she has tons of little buggers attached to her.

I'm wondering if water temperature or something like that is effecting the sex of the fry.. Is this true?

I'm thinking the water might be too warm...

Any info is appreciated. Thank you

 

[raptorrex]

Here's the deal.. We have a female alleni that has had 2 broods so far.. All the fry have turned out to be females..

She has another brood going right now.. The eggs just hatched, and she has tons of little buggers attached to her.

I'm wondering if water temperature or something like that is effecting the sex of the fry.. Is this true?

I'm thinking the water might be too warm...

Any info is appreciated. Thank you

not really something that is reported anyway. though i have known cray change sex, its usually the other way around, male to female. but it can be anywhere from 3 t0 7 months for the cray to reach sexual maturity.

 

[Colin_T]

It could be genetic, that is the female is going to always produce lots of female offspring because of her genetic makeup. Over the years yabby farmers and government departments in Australia have been selective breeding yabbies so they produce mainly male young. The males grow faster and bigger so by using this particular bloodline, they get more males and can sell them sooner for more money.
The other option is water chemistry or temperature, which you mentioned. Temperature shouldn't make any difference to fish/ crustaceans but PH has been known to change the percentage of male to female young. Generally the higher PH (above 7.0) will give you more males, and the lower PH (below 7) will give you more females. But it depends on what the PH is for the species in its natural habitat. If it comes from very alkaline water then a higher PH is unlikely to make much difference, but a low PH could encourage more female young.

 

[raptorrex]

It could be genetic, that is the female is going to always produce lots of female offspring because of her genetic makeup. Over the years yabby farmers and government departments in Australia have been selective breeding yabbies so they produce mainly male young. The males grow faster and bigger so by using this particular bloodline, they get more males and can sell them sooner for more money.
The other option is water chemistry or temperature, which you mentioned. Temperature shouldn't make any difference to fish/ crustaceans but PH has been known to change the percentage of male to female young. Generally the higher PH (above 7.0) will give you more males, and the lower PH (below 7) will give you more females. But it depends on what the PH is for the species in its natural habitat. If it comes from very alkaline water then a higher PH is unlikely to make much difference, but a low PH could encourage more female young.

i can discount the PH as a cause. i have Cray breeding acquaintances who keep P Alleni in anything from 6.8 to 8.7 ( concrete as they call it). it has no effect on the sex of the offspring. water temp too, it is a factor in breeding, but not in sex determination. as colin says, you may just have a "female fountain"

 

[Colin_T]

"female fountain"
lol, I like that

 

[raptorrex]

"female fountain"
lol, I like that

Ahh yes, , its what i call my wife, and her mother. there aint a boy in sight in the family

 

[Colin_T]

Yeah I have a friend who has lots of daughters but no sons, and I know other people who have nothing but male children in their family. Ahh the wonders of genetics. In fact the sons in one of the families all look very similar and are often confused for twins, triplets or whatever it is called when there is a bunch of them. They resemble each other so much that the wives sometimes get them confused, (not sure if that is deliberate so they can be promiscuous). If you look closely and hear them speak you can notice little differences, but if you saw them standing in line you would swear they are all from the same litter.

 

[vancouver]

Well then.. I guess I will have to find someone locally that has the same issue but with MALES!

Thanks for the info!

 

[raptorrex]

Well then.. I guess I will have to find someone locally that has the same issue but with MALES!

Thanks for the info!

may be able to help there! check your pm's. but "local" is a relative term