Broody Hen Thread!

[julie0477]

If sex is determined by the hen and is already set when it is laid, how can temperature have anything to do with it? I was just saying if temps are a little high (or not ideal) that maybe only the roosters are surviving. I don't think temperature can actually CHANGE the sex of the chick. I'll look at the link you supplied in a bit. Thanks for the info!

 

[lazy gardener]

Exactly what you just said. Certain temps favor the development of one gender over the other. So, your hatch might swing in favor of one gender, while the other gender dies before hatch. Do your eggs typically hatch right on time? ( some pips, and maybe an early hatch on day 20, most of the hatch on day 21, with a few laggers on day 22?) Or are they earlier or later than that?

 

[GitaBooks]

A birds gender is determined by genetics, if you test their blood you can tell if they are male or female. Some reptiles, however, develop into a male or a female by temperature. I hear that you cannot test their blood to determine gender when they are young, since it isn't in their DNA.

 

[CanaDawn]

Birds are "opposite" to mammals in that the female of birds determines the sex of the offspring. In humans, males are XY and give one half of that to their offspring, while females are XX and can only give an X. Chickens, it's the other way, and the female has different sex chromosomes, and the roo has two the same.

BUT: http://www.independent.co.uk/news/a-drop-in-temperature-can-change-the-sex-of-chickens-1238516.html

It looks like, genetics aside, a chilled male egg will end up being functionally female. IF though, you cross those fe(male) birds, the offspring will be ALL male (because the fe(male) has only got one type of sex chromosome to pass along.) Make sense?

Also "The chilling technique only changes the sex of 10 per cent of males into females, although if these birds are then crossed with normal males an all-male brood results."

So...if you're getting no females at all, you may want to change your hens, cuz they may be chilly roosters laying eggs...

Even if you get chilled-to-female hatches, those new "hens" won't produce hens the next generation, because you don't actually change the sex of the bird, just the function of the chilled roos.

Interesting stuff, zoology.

 

[CanaDawn]

A birds gender is determined by genetics, if you test their blood you can tell if they are male or female. Some reptiles, however, develop into a male or a female by temperature. I hear that you cannot test their blood to determine gender when they are young, since it isn't in their DNA.

From what I read, the part of the genes responsible for sex determination is not identified as easily, and not readily done via current DNA testing processes. (ETA - I'm referring to reptile sexing via DNA/blood. Avians can be DNA sexed via blood, etc)

 

[GitaBooks]

From what I read, the part of the genes responsible for sex determination is not identified as easily, and not readily done via current DNA testing processes.

I'm not sure about chickens, but parrots are regularly DNA tested to determine gender since you can't tell them apart externally. Some people test chickens as well, I heard they do it with silkies since they are difficult to tell apart.

 

[CanaDawn]

I'm not sure about chickens, but parrots are regularly DNA tested to determine gender since you can't tell them apart externally. Some people test chickens as well, I heard they do it with silkies since they are difficult to tell apart.

Yes, birds can be.
Reptiles though, which you were referring to in your earlier post, not so much. Reptile DNA isn't as clear in its sex chromosomes, and from what I read, the technology/knowledge isn't up to the job of doing DNA sex testing.
Birds can be DNA sexed via blood.

 

[GitaBooks]

Yes, birds can be.
Reptiles though, which you were referring to in your earlier post, not so much. Reptile DNA isn't as clear in its sex chromosomes, and from what I read, the technology/knowledge isn't up to the job of doing DNA sex testing.
Birds can be DNA sexed via blood.

Oh, sorry, I was confused.

Yes, it is very hard to tell male reptiles from females.

 

[CanaDawn]

Oh, sorry, I was confused.

Yes, it is very hard to tell male reptiles from females.

I edited for clarity outside of quotes.

It's tricky...not even acting female is enough...Even if a chicken lays an egg, it may only be functionally female, and I would fully expect that it is similar with reptiles, as they aren't so far removed from avians. I would be willing to bet a very nice coffee that temperature shifts function but not gene expression in reptiles too.

(Sideline (skip if drift annoys you)): In people, what determines the physical attributes of "gender" is testosterone...in a chromosomally male embryo, if the testosterone production fails early enough, the body will look female, but the genes will be XY. I presume temperature isn't considered an issue with mammal development due to internal incubation in homeothermic mamas...stay tuned to see if that changes when in vitro babies are cooked in the dish longer/to term!)

 

[nanachic]

Well my first hatch i had 15 eggs in the incubator and 10 hatched. Which I thought was an awesome thing being it was my first time. The other eggs did not hatch but when I open them up they were fully developed. Kind of looks like I might have shrunk wrap them that was my thought. Because I had open the incubator quite a few times. But then when I tried my second timeI got 50 percent in My 3rd hatch I got 50%. So what I was thinking is maybe the females are not hatching. And they are hatching in the normal time frame.