Air sac determines sex.

[aart]

I recently read a booklet by Thomas Quisenberry that was titled How to Tell The Sex of an Egg Before Incubation. In the book it described candling a chicken egg prior to incubation. If the air sac is off center and can only be viewed from the front and sides of the egg, a female will hatch. If the air sac is centered in the end and can be viewed from all sides, a male will hatch. This was proved in a University study. Mrs. Noda Fry was the person who reported this method to Mr. Quisenberry. She hatched 96 eggs and 92 were female. She also described holding a chick by the head. If the legs relax and hang, this is a cockerel. If the legs draw up toward the head/abdomen, this is a female.
Has anyone else ever tried this? I am about to put a couple dozen eggs in the incubator that I have candled using this method.

Do you have a link to this study?
Where did you get this booklet?

Did you trace the air cells on all the eggs, and can you post pics of them??

 

[tlcmurphy]

Actually, in chickens the female determines the sex of the chick.

 

[JacinLarkwell]

It is my understanding that the male determines the sex of the offspring

Not in birds. The female determines the sex

 

[OrpingtonManiac]

It is my understanding that the male determines the sex of the offspring

FYI
In chickens its the female that determines the sex of the offspring. Females sex chromosomes are ZW and males are ZZ.

 

[Mill Chick]

I recently read a booklet by Thomas Quisenberry that was titled How to Tell The Sex of an Egg Before Incubation. In the book it described candling a chicken egg prior to incubation. If the air sac is off center and can only be viewed from the front and sides of the egg, a female will hatch. If the air sac is centered in the end and can be viewed from all sides, a male will hatch. This was proved in a University study. Mrs. Noda Fry was the person who reported this method to Mr. Quisenberry. She hatched 96 eggs and 92 were female. She also described holding a chick by the head. If the legs relax and hang, this is a cockerel. If the legs draw up toward the head/abdomen, this is a female.
Has anyone else ever tried this? I am about to put a couple dozen eggs in the incubator that I have candled using this method.

Im going to be hatching some silkie eggs soon and I will see if anything comes of it! It would be amazing if it is true!

 

[KS_Chicken_Wrangler]

I'm not sure of the accuracy here, but I found the study intriguing. Those who are consistent hatchers, have you found any truth to this hypothesis (or is this a theory with with study involved?)?

https://pmc.ncbi.nlm.nih.gov/articles/PMC9832119/

 

[horselover1999]

I just read the abstract and part of the intro and I can already poke a couple holes into their study. You should not be able to poke holes into a correctly done peer-reviewed publication.
1) The second sentence mentions ethicality, which depends on the person and is not a fact. There are several ways to humanely and effectively euthanize chicks.
2) They might say it is 80% effective, so just don't incubate the "male" eggs, "saving 5.65 billion chicks from being slaughtered." That is ignoring the approximately 20% of female chicks in the "male" eggs, and the approximately 20% of male chicks in the "female" eggs. They don't look at the amount of chicks that makes up this combined 40%, so almost half, about the normal male:female ratio.
3) The authors are in electrical engineering, and didn't bring in a co-author that is in a relevant department?
I didn't want to read the rest of it, I don't trust their accuracy.

Egg shape is determined by the shape of the hen's uterus/shell gland, and might change over time, but very, very, gradually over her productive life.
Hens do determine the sex of the chick with ZW, while rooster have ZZ chromosomes, but that affects the embryo, not the shape of the egg.
While I was at my internship with Tyson's genetics supplier, Cobb-Vantress, they were talking about a new method to determine sex in ovo by shining a laser into/through the egg and reading the wavelengths it produced. I haven't looked into it, though, and I think it would be too expensive for the average person to get if it was proved accurate. It also might have to be done before the egg is incubated, and require the shell to be opened a bit, increasing the chance of bacterial contamination and decreasing hatch rate.

Holding chicks by the head to see their reaction is inaccurate. Their reaction really depends on the bird's personality.

Signed
-Bachelors of Science, Poultry Science
-Masters of Science, Animal Science (Poultry)

 

[OrpingtonManiac]

I just read the abstract and part of the intro and I can already poke a couple holes into their study. You should not be able to poke holes into a correctly done peer-reviewed publication.
1) The second sentence mentions ethicality, which depends on the person and is not a fact. There are several ways to humanely and effectively euthanize chicks.
2) They might say it is 80% effective, so just don't incubate the "male" eggs, "saving 5.65 billion chicks from being slaughtered." That is ignoring the approximately 20% of female chicks in the "male" eggs, and the approximately 20% of male chicks in the "female" eggs. They don't look at the amount of chicks that makes up this combined 40%, so almost half, about the normal male:female ratio.
3) The authors are in electrical engineering, and didn't bring in a co-author that is in a relevant department?
I didn't want to read the rest of it, I don't trust their accuracy.

Egg shape is determined by the shape of the hen's uterus/shell gland, and might change over time, but very, very, gradually over her productive life.
Hens do determine the sex of the chick with ZW, while rooster have ZZ chromosomes, but that affects the embryo, not the shape of the egg.
While I was at my internship with Tyson's genetics supplier, Cobb-Vantress, they were talking about a new method to determine sex in ovo by shining a laser into/through the egg and reading the wavelengths it produced. I haven't looked into it, though, and I think it would be too expensive for the average person to get if it was proved accurate. It also might have to be done before the egg is incubated, and require the shell to be opened a bit, increasing the chance of bacterial contamination and decreasing hatch rate.

Holding chicks by the head to see their reaction is inaccurate. Their reaction really depends on the bird's personality.

Signed
-Bachelors of Science, Poultry Science
-Masters of Science, Animal Science (Poultry)

I did also see a couple of things in that paper that made me doubt its accuracy a little too Lol

 

[KS_Chicken_Wrangler]

I just read the abstract and part of the intro and I can already poke a couple holes into their study. You should not be able to poke holes into a correctly done peer-reviewed publication.
1) The second sentence mentions ethicality, which depends on the person and is not a fact. There are several ways to humanely and effectively euthanize chicks.
2) They might say it is 80% effective, so just don't incubate the "male" eggs, "saving 5.65 billion chicks from being slaughtered." That is ignoring the approximately 20% of female chicks in the "male" eggs, and the approximately 20% of male chicks in the "female" eggs. They don't look at the amount of chicks that makes up this combined 40%, so almost half, about the normal male:female ratio.
3) The authors are in electrical engineering, and didn't bring in a co-author that is in a relevant department?
I didn't want to read the rest of it, I don't trust their accuracy.

Egg shape is determined by the shape of the hen's uterus/shell gland, and might change over time, but very, very, gradually over her productive life.
Hens do determine the sex of the chick with ZW, while rooster have ZZ chromosomes, but that affects the embryo, not the shape of the egg.
While I was at my internship with Tyson's genetics supplier, Cobb-Vantress, they were talking about a new method to determine sex in ovo by shining a laser into/through the egg and reading the wavelengths it produced. I haven't looked into it, though, and I think it would be too expensive for the average person to get if it was proved accurate. It also might have to be done before the egg is incubated, and require the shell to be opened a bit, increasing the chance of bacterial contamination and decreasing hatch rate.

Holding chicks by the head to see their reaction is inaccurate. Their reaction really depends on the bird's personality.

Signed
-Bachelors of Science, Poultry Science
-Masters of Science, Animal Science (Poultry)

I greatly appreciate the insight, especially considering your background and experience. About the only way I know to sex chicks with any accuracy is the wing feather method while they are still fluff balls.

 

[FrostRanger]

I greatly appreciate the insight, especially considering your background and experience. About the only way I know to sex chicks with any accuracy is the wing feather method while they are still fluff balls.

Feather sexing can only be done on certain crosses. If the chick doesn't have the right genetics it won't work