Why roosters only?

[Hysteria]

I’m wondering what is the reason that only roosters get born in a small home incubator/hatcher?
Temperatures/humidity/motions all decent.
Successful births, but always all are roosters and not one hen.
Has to be a reason.
Does anybody have wisdom on this?
Appreciate!

 

[JedJackson]

The sex of baby chicks is decided by the mother hen in her ovum, and is unaffected by sperm. Totally different from humans. So temperature won't affect gender. I doubt egg shape makes any difference either, but I can't state that as a fact, just a suspicion. So basically it is down to what the hen's body chooses, and there is no way to change it. Some hens may produce more male offspring than others. I'm not sure of that, either. But more likely it is just pure chance, and you've had bad luck. Maybe try hatching eggs from different hens next time, or buying sexed chicks from TSC or a hatchery.

 

[Tstraub]

Two out of two followed by three out of three males is well within normal chance. It happens with people all the time and nobody thinks it’s terribly out of the ordinary. My parents had three sons and no daughters. I have four sons and no daughters.

 

[thlayli]

Well from two attemps: first 4 eggs in a small simple incubator; got 2 succsessful births of 4; both roosters who died because of poorly mounted heating lamp( by me…) what did fry them ( was devastated); second attempt with a different cheap Chinese hatcher “ fully automated” from 7 eggs 3 births, all roosters; the remaining 4 : one didn’t developed; 3 died in the egg almost fully developed.

So 50% confirmed cockerels for the first hatch, and a little less than that for the second. That's entirely normal. Each individual egg has a 50/50 shot of being male or female and sometimes you just get weird RNG. My last batch of 19 had 15 cockerels. The batch before that had 8/18. Sometimes you flip a coin 10 times and 8 times is tails.

As for the temperature myth, the easiest way to test it would be with sex links or autosexes. Separate out the "boy" eggs from the "girl" eggs and just wait for them to hatch, and you'll immediately have your answer. I suspect it's probably just an old wives' tale, though, otherwise hatcheries wouldn't have as many extra boy chicks as they do.

 

[dekel18042]

I’m wondering what is the reason that only roosters get born in a small home incubator/hatcher?
Temperatures/humidity/motions all decent.
Successful births, but always all are roosters and not one hen.
Has to be a reason.
Does anybody have wisdom on this?
Appreciate!

Some more information would help. How many eggs are you talking about hatching roosters? That would make a difference, whether it is three out of three (perhaps not unusual) or 15 out of fifteen which would be. How many eggs total, that is how many in each batch are not hatching?
I once hatched 7/7 pullets and was not happy because I was starting a new breed and needed a rooster. I've also hatched 2/2 roosters.

 

[JacinLarkwell]

Sounds like your hens just throw sons. I have a small incubator and hatch plenty of females most hatches

 

[Svetik]

My last hatch was all females 6 of 8 eggs, 2 died inside the egg.

But before I started I was testing the theory of some comments I came across on the web about hatching. They mentioned about selecting a rounder eggs that didn't have a noticeable small end. So I tried it.

To me there's some truth to it after my test. But this was only one test so I can't make a comparison result.

That said, try looking for more rounder eggs to hatch. Remember you can leave fertile eggs on the kitchen counter for 3 weeks till you have enough. Hatch 6 minimum or more to view results.

Да, согласна с вами. Есть такая версия. Одна женщина сильно утверждала, что она уберёт шустрые яйца так как это петухи. Но, у меня пока нет этому утверждению. Ещё пока нет способа, что бы 100%уверенностью выбрать яйцо по полу. На всё воля Божья!
Narrow, sharp eggs

 

[dekel18042]

My last hatch was all females 6 of 8 eggs, 2 died inside the egg.

But before I started I was testing the theory of some comments I came across on the web about hatching. They mentioned about selecting a rounder eggs that didn't have a noticeable small end. So I tried it.

To me there's some truth to it after my test. But this was only one test so I can't make a comparison result.

That said, try looking for more rounder eggs to hatch. Remember you can leave fertile eggs on the kitchen counter for 3 weeks till you have enough. Hatch 6 minimum or more to view results.

This theory has been disproved in several magazine articles I have read.
I've also tried it to no avail. I have some hens who always lay a round egg and have produced both sexes.

 

[BarnyardChaos]

Could be myth, but I've heard that temperature plays a role. Higher temperatures result in males.

So temperature won't affect gender.

There is an explanation for why temperature plays a role. I apologize for not being able to find the reference at the moment, but I recall a study that showed incubator temperature is slightly related to the mortality of male vs. female chicks - so that more male chicks survive higher temperatures while females survive better at lower temperatures. Mind you now, the difference was very minimal - something like 1% or 2% - so if you have a full incubator load of, say, 48 eggs, then incubating at lower temperature may result in maybe one more female chick surviving than at a higher temperature.

 

[Tonyroo]

My last hatch was all females 6 of 8 eggs, 2 died inside the egg.

But before I started I was testing the theory of some comments I came across on the web about hatching. They mentioned about selecting a rounder eggs that didn't have a noticeable small end. So I tried it.

To me there's some truth to it after my test. But this was only one test so I can't make a comparison result.

That said, try looking for more rounder eggs to hatch. Remember you can leave fertile eggs on the kitchen counter for 3 weeks till you have enough. Hatch 6 minimum or more to view results.