What if any outside infulences decide the sex of a chick???

[Meat Hunter]

Was reading over some of the posts where people were talking about getting a boatload of roos when they wanted pullets when ordering from such places as TSC or halfassesd hatcheries. This started me thinking about something that occurs in the wild with alligators/crocodiles. Temperature-dependent sex determination where the temperature, NOT genetics determines the outcome of the sex. Being that birds are believed to be a distant relative of reptiles, (scalely legs), I wondered if there was anything one could do to put the odds in their favor to hatch out more pullets? Temperature/humidity manipulation during certain stages of the development? There is one species of bird that this does apply to, the Australian Brush Turkey.

 

[Gallusfarm]

Wouldn't it be great if it were true, but it is not. There have been many studies done, and there is no evidence that a temp change at any time during incubation alters the ratio of males to females.

Here's a great article:

http://people.eku.edu/ritchisong/avianreproduction.html

 

[FireTigeris]

Well, kinda- sex in birds is determined at fertilization by the sex chromosomes.

However because (speculation) males have two full sets of chromosomes and females have one set and then the sex chromosome (opposite of mammals- fact) you can make harsh conditions for the eggs (high temps too low humidity etc) and kill the females.

there is another post about this high temps spikes for short periods does not kill males...

 

[quetsweyo]

That is a very interesting idea. Do bush turkeys bury their eggs in a big pile of dirt and leaves and cover and uncover them as the temp changes? I think birds came from dinosaurs who were warm-blooded and some had feathers but then dinos good chance came from reptiles, so?I dont know, just sounds like a possible experiment, but someone here mentioned high heat kills female eggs-dont want a load of roosters or drakes as I dont eat them, yet. Sorry i am babbling, dinos/bird theory does that. Quetsweyo

 

[Ridgerunner]

Quote:
If there were anything to this, considering how much money has been spent by the commercial operations and the universities studying this exact thing, it would be common knowledge and in use by everyone.

 

[FireTigeris]

Quote:
If there were anything to this, considering how much money has been spent by the commercial operations and the universities studying this exact thing, it would be common knowledge and in use by everyone.

Exactly, but there are ways to accidentally favor males... too bad...

there were scholarly links in the other thread but for some reason my "Google Fu" is weak today.

 

[cmom]

Male birds have two Z chromosomes and female birds have a Z and a W chromosome, such as in human females have two X chromosomes and males have a X and a Y chromosome. In humans, the males determines the sex of a child from the X and Y chromosomes as the female passes on the X chromosome and the male either an X or Y which determines what sex the child will be. In birds The males pass on the Z chromosome and the female passes on either a Z or W which determines what sex a chick will be.