Can factors like incubation environment or parent genetics affect the sex ratio of a brood? Or is it always theoretically more or less 50/50?
Sorry for the super basic question
Sorry for the super basic question
Is the sex ratio always 50/50?
- Thread starter mosseater
- Start date
Incubation doesn't affect gender ratio but the genetics of the hen can.
Theoretically it averages 50/50.
If there was any way to effect that the hatcheries would be doing it.
If there was any way to effect that the hatcheries would be doing it.
Shoot, forget the hatcheries, I'd be doing it if there was a way to manipulate the sex ratio in chicks!
But, despite many, many, many attempts, no one has been able to actually show a consistent and statistically significant connection between incubation or storage conditions and the ratio of males and females in a hatch.
There are some studies that claim to have connected temperature, whether in storage or in incubation, to sex ratio--but there are just as many that have found no significant connection.
There are many chicken keepers that have claimed to find a connection between the shape or size or storage of eggs and the sex ratios of the chicks that hatch, but just as many others have tried the same techniques with no such connection found in their own attempts.
There simply is no connection beyond that the hen puts the genetic material for either a male or a female in each egg and that is what determines what will hatch from it.
The statistics say that if you hatch enough, eventually you will hit that 50-50 mark. But on the small scale, numbers tend to skew. Look at flipping a coin. Theoretically, there's an equal chance of getting either outcome, a heads or a tails, when you do. But if you flip a coin 6 times, you don't always get exactly 3 heads and 3 tails as a result. In fact, quite often it's skewed one direction or the other.
The same goes with hatching. There are equal odds of a male or female hatching from each and every egg you incubate. If you hatch 5 chicks and all of them are pullets, as one of my hens did this past summer, you might think you've gone and found the secret technique to making an all female hatch! But among a larger quantity, it balances out. Though that hen of mine managed to hatch 5 pullets out of the 5 eggs she successfully incubated, my overall totals last year, between other hens hatching and incubators running, were exactly equal; 16 males and 16 females. The year before, I had a hen hatch all males in her brood, but out of the 70 chicks that hatched on the farm overall, it ended up being exactly 35 males and 35 females. Rather uncanny!
To make a long post short, nothing we do will impact how many males or females hatch out of the eggs we or our hens incubate. In theory, you could narrow down which hens throw more females and keep breeding from them, but there is no guarantee that they or their daughters will continue that trend in subsequent hatches. All we can do is hatch, hope, and have ourselves a lot of chicken soup with the extras we end up with.
But, despite many, many, many attempts, no one has been able to actually show a consistent and statistically significant connection between incubation or storage conditions and the ratio of males and females in a hatch.
There are some studies that claim to have connected temperature, whether in storage or in incubation, to sex ratio--but there are just as many that have found no significant connection.
There are many chicken keepers that have claimed to find a connection between the shape or size or storage of eggs and the sex ratios of the chicks that hatch, but just as many others have tried the same techniques with no such connection found in their own attempts.
There simply is no connection beyond that the hen puts the genetic material for either a male or a female in each egg and that is what determines what will hatch from it.
The statistics say that if you hatch enough, eventually you will hit that 50-50 mark. But on the small scale, numbers tend to skew. Look at flipping a coin. Theoretically, there's an equal chance of getting either outcome, a heads or a tails, when you do. But if you flip a coin 6 times, you don't always get exactly 3 heads and 3 tails as a result. In fact, quite often it's skewed one direction or the other.
The same goes with hatching. There are equal odds of a male or female hatching from each and every egg you incubate. If you hatch 5 chicks and all of them are pullets, as one of my hens did this past summer, you might think you've gone and found the secret technique to making an all female hatch! But among a larger quantity, it balances out. Though that hen of mine managed to hatch 5 pullets out of the 5 eggs she successfully incubated, my overall totals last year, between other hens hatching and incubators running, were exactly equal; 16 males and 16 females. The year before, I had a hen hatch all males in her brood, but out of the 70 chicks that hatched on the farm overall, it ended up being exactly 35 males and 35 females. Rather uncanny!
To make a long post short, nothing we do will impact how many males or females hatch out of the eggs we or our hens incubate. In theory, you could narrow down which hens throw more females and keep breeding from them, but there is no guarantee that they or their daughters will continue that trend in subsequent hatches. All we can do is hatch, hope, and have ourselves a lot of chicken soup with the extras we end up with.
- Mar 3, 2017
- 20
- 91
- 114
I recently ran across a book by Thomas Quisensberry titled How to Tell the Sex of an Egg Before Incubation. A Mrs. Noda Fry determined (in the early 1900's) that sex could be determined by looking at the air sac. When candling the fresh egg, if the sac on a pre incubated egg is to the side of the round end of the egg, it is a hen. If the sac is centered at the end of the egg or just slightly off center, a rooster will hatch. This was proven at a University in Missouri. Out of 96 eggs, 92 hatched pullets. I am currently trying this method.Shoot, forget the hatcheries, I'd be doing it if there was a way to manipulate the sex ratio in chicks!
But, despite many, many, many attempts, no one has been able to actually show a consistent and statistically significant connection between incubation or storage conditions and the ratio of males and females in a hatch.
There are some studies that claim to have connected temperature, whether in storage or in incubation, to sex ratio--but there are just as many that have found no significant connection.
There are many chicken keepers that have claimed to find a connection between the shape or size or storage of eggs and the sex ratios of the chicks that hatch, but just as many others have tried the same techniques with no such connection found in their own attempts.
There simply is no connection beyond that the hen puts the genetic material for either a male or a female in each egg and that is what determines what will hatch from it.
The statistics say that if you hatch enough, eventually you will hit that 50-50 mark. But on the small scale, numbers tend to skew. Look at flipping a coin. Theoretically, there's an equal chance of getting either outcome, a heads or a tails, when you do. But if you flip a coin 6 times, you don't always get exactly 3 heads and 3 tails as a result. In fact, quite often it's skewed one direction or the other.
The same goes with hatching. There are equal odds of a male or female hatching from each and every egg you incubate. If you hatch 5 chicks and all of them are pullets, as one of my hens did this past summer, you might think you've gone and found the secret technique to making an all female hatch! But among a larger quantity, it balances out. Though that hen of mine managed to hatch 5 pullets out of the 5 eggs she successfully incubated, my overall totals last year, between other hens hatching and incubators running, were exactly equal; 16 males and 16 females. The year before, I had a hen hatch all males in her brood, but out of the 70 chicks that hatched on the farm overall, it ended up being exactly 35 males and 35 females. Rather uncanny!
To make a long post short, nothing we do will impact how many males or females hatch out of the eggs we or our hens incubate. In theory, you could narrow down which hens throw more females and keep breeding from them, but there is no guarantee that they or their daughters will continue that trend in subsequent hatches. All we can do is hatch, hope, and have ourselves a lot of chicken soup with the extras we end up with.
PetalAndPlume
Songster
- Mar 6, 2023
- 216
- 504
- 171
Please let us know if this is actually true! I will try it myself for my next hatch as well.
Carrot_Mama
Chirping
- Feb 16, 2025
- 59
- 136
- 96
Interesting! Do you have a link or reference? I would love to read more on this. TY!
I don't but I know that there's this information on here some.
It’s page 29. Chapter 2.
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