using extremely high temps to hatch only females

[MysteryChicken]

I hope that continues to be the case. Perhaps it has nothing to do with your chilling them, but either way, it’s got a great result

We'll find out though.

 

[BDutch]

But the hen determines the sex of the chick.

With humans it is the sperm of the man that makes male or female.
The man produces as much female as male sperm*. I can’t imagine that this is any different for chickens.**
The timing of the sex is something that influences the boy-girl ratio. If the sperm is injected two days before the ovulation chances are bigger to get a girl. If the sex sex takes place after ovulation, chances are bigger for a boy.

*source startpagina Nl translated by google:
Sperm contains about the same amount of male and female sperm. This is because chromosome pairs are pulled apart during the production of sperm cells. Half of the chromosomes end up in one sperm cell, the other half in the other sperm cell. The sperm that receives the X from the X / Y pair is female, the sperm that receives the Y from that pair is male. In the source extensive description of what I here very simplistically call the 'pulling apart' of chromosome pairs. That therefore produces as many male as female sperm cells. Because things sometimes go wrong or a sperm cells drop prematurely, there may be some difference, but it will never be very different.

**
p.s. an expert among us explained this is different for chickens. I need more imagination.

.......

In chickens, of course, things are flip flopped. Males have two of the same sex chromosome, ZZ, while females have ZW. My theory is that there is something stabilizing about having two of the same chromosome. That's why we see these slightly higher rates of survival in female mammals. Unfortunately, it means that those suboptimal conditions you're talking about favor males. You could go too hot, or too cool, too dry or too wet, males would still be more prevalent in the surviving chicks.

Let's face it, we don't do artificial incubation like the experts (the chickens.) We do all right, sometimes we do great, but when we don't, embryos die. When some can survive, who survives? I know that for me, when things go wrong, that's when I start to see the all cockerel hatches. I think, like male mammals, female chickens are more susceptible when things aren't just right. The male embryos are hardier and more likely to survive our attempts at incubating, as long as we don't get it too terribly wrong.

 

[HuffleClaw]

With humans it is the sperm of the man that makes male or female.
The man produces as much female as male sperm*. I can’t imagine that this is any different for chickens.
The timing of the sex is something that influences the boy-girl ratio. If the sperm is injected two days before the ovulation chances are bigger to get a girl. If the sex sex takes place after ovulation, chances are bigger for a boy.

*source startpagina Nl translated by google:
Sperm contains about the same amount of male and female sperm. This is because chromosome pairs are pulled apart during the production of sperm cells. Half of the chromosomes end up in one sperm cell, the other half in the other sperm cell. The sperm that receives the X from the X / Y pair is female, the sperm that receives the Y from that pair is male. In the source extensive description of what I here very simplistically call the 'pulling apart' of chromosome pairs. That therefore produces as many male as female sperm cells. Because things sometimes go wrong or a sperm cells drop prematurely, there may be some difference, but it will never be very different.

It’s the opposite in chickens.

 

[BDutch]

Source: a Dutch poultry website https://www.pluimveeweb.nl/artikel/...achtsverhouding-van-nakomelingen-beinvloeden/
Translated with google .

The research also showed that laying hens can influence the sex ratio of their offspring. It was found that after reduced ration feeding or after treatment with corticosterone, the weight loss of the layers and their eggs were significant predictors of the primary sex ratio.

The study provided three different indications that meiotic drive in the pre-ovulatory follicle underlies the sexual intercourse.

 

[BDutch]

More info/ part of an article. This is from another Dutch newssite for farmers. https://www.boerderij.nl/Pluimveeho...ethode-geslachtsbeinvloeding-kuiken-1594683W/

Researcher Muhammad Aamir Aslam has conducted experiments with a feed restriction and with adding the stress hormone corticosterone to the feed to increase its concentration in the blood. These experiments did produce shifts in the ratio between hen and rooster chicks, but the methods are not practically applicable. In the experiments, for example, feed restriction led to more male chicks in hens that lay light eggs and in hens that laid heavy eggs to more female chicks. The corticosterone experiment had the opposite effect in light and heavy hens and resulted in a lower laying frequency and a lower percentage of fertilized eggs in the heavier hens.

 

[TheFarm41]

Has anyone tried this, or read any articles on it?
yes, yes, I know roosters are important- but as a person who always gets 80% roosters I am wondering if this has been done. I know with other species (human for example) female sperm can survive less than ideal conditions much better than male- so I was hoping someone else had done an experiment.... otherwise I might.

My experience with hatching is that it is a crap shoot - you get what you get. Most hatches feel like they are 75% roosters. Even though I'm certain if you average it out it is 50/50 split just like humans. However, my most recent hatch was 30 eggs in the incubator, 26 hatched, 16 hens 10 roos, best luck ever! The important part is to have an exit strategy for the roosters.

Sometimes we raise the roosters long enough to get them to a good butcher weight. Usually about 12 to 18 months. Many people assume that egg breeds will be gamey or tough especially if they are over a year old. This just isn't true! The best chicken I've ever eaten is a barn yard rooster. Coq A Vin is traditionally made with a rooster and it is delicious! It is best if the rooster is free ranging. Large variety of forage helps reduce feed expense and makes for a more flavorful bird.

You can also sell the roosters from your hatch. We usually wait until we are certain who is hen and who is roo, usually around 4 months. We've gotten anywhere from $5-10 per rooster, depending on how much of a hurry we were in to get rid of them.

 

[Minky]

My experience with hatching is that it is a crap shoot - you get what you get. Most hatches feel like they are 75% roosters. Even though I'm certain if you average it out it is 50/50 split just like humans. However, my most recent hatch was 30 eggs in the incubator, 26 hatched, 16 hens 10 roos, best luck ever! The important part is to have an exit strategy for the roosters.

Sometimes we raise the roosters long enough to get them to a good butcher weight. Usually about 12 to 18 months. Many people assume that egg breeds will be gamey or tough especially if they are over a year old. This just isn't true! The best chicken I've ever eaten is a barn yard rooster. Coq A Vin is traditionally made with a rooster and it is delicious! It is best if the rooster is free ranging. Large variety of forage helps reduce feed expense and makes for a more flavorful bird.

You can also sell the roosters from your hatch. We usually wait until we are certain who is hen and who is roo, usually around 4 months. We've gotten anywhere from $5-10 per rooster, depending on how much of a hurry we were in to get rid of them.

yes, thanks for the response... id be pretty happy with 16 F and 10 male- great luck! Im always the other way around. I can get $10 a rooster MAYBE, once he is 12-14 weeks old..., but I get $10 for a day old... so I sell straight run. its just a hobby- just want to sell the ones I dont want LOL not trying to make millions on chicks. hehehehe
no one around here wants a 5 week old rooster, and feeding them to 16 weeks and selling for 5 or 10 dollars makes no sense. I'd rather eat my roosters- but we find after 18 weeks they are only good for soup or grinding.
We have eaten a 1.5 yr old rooster- but dont want to make a habit of it.

 

[ladybrasa]

https://www.google.com/amp/s/www.independent.co.uk/news/drop-temperature-can-change-sex-chickens-1238516.html?amp

Hmmm, no links/references, and it says industry hasn’t funded anything. Females, at least CX, are eaten - “Cornish hens”. What it sounds like is the guy is causing “deformities”/developmental abnormalities in the reproductive organs since it says the chicks are genetically male, but develop with female equipment instead. And apparently can lay fertile eggs ...

If this is true (definitely need more than one short newspaper article), then to the person that chills their eggs (MysteryChicken?) it would be very interesting to get genetic gender testing done on your chill-hatched girls!

 

[ladybrasa]

Another consideration - how is sex determination after hatch happening? Waiting a minimum of 3 months for gender-specific feathering to come in? Auto-sexing or sex-linkage? As I understand it, comb color and size, tail feathers, behavior, even crowing arehighly suggestive but not 100% reliable predictors.

 

[JacinLarkwell]

Another consideration - how is sex determination after hatch happening? Waiting a minimum of 3 months for gender-specific feathering to come in? Auto-sexing or sex-linkage? As I understand it, comb color and size, tail feathers, behavior, even crowing arehighly suggestive but not 100% reliable predictors.

Vent sexing usually