Spring chicks vs fall chicks ... effect on gender?

[Mace Gill]

I mentioned to a friend that my hen just hatched chicks on Monday.

My friend is from Estonia and told me that their grandmother (still in Estonia), who has all manner of multi generational knowledge on raising chickens, duck, gees, and guineas, had said that spring hatches tend to have more roosters while fall hatches have more hens.

Naturally, I said that I don't think science could back up your grandmother's claims, and my friend agreed, but ...

I do place some stock in the words of my elders, folk knowledge, and the like. I am very curious to know if anyone else has heard this and what are your observations!

Seems like most of us try to hatch in the spring, of course ... but has anyone ever heard of or noticed a difference in gender ratio from one to the other?

Incidentally, mine hatched seven chicks on July 10th and I am THINKING I have five hens and two roos.

 

[eggbert420]

I guess it could be possible??

Nicholas Schoon wrote.
If the temperature is dropped by a few
degrees for three days during the embryological development of a freshly laid egg, some chickens which should hatch out male instead become female.They have the genes and chromosomes for maleness but they are fully functional females able to lay fertile eggs. If they are then crossed with normal males, the resulting chicks are all male, said Professor Mark Ferguson of the University of Manchester.This is what interests the poultry industry.All the female chicks which hatch from the breeding stock which provides the broiler chickens we eat are destroyed after hatching. Only the males put on enough meat, at sufficient speed, to make them economically viable. So there could be large savings if the breeding stock could be made to produce only males.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.Professor Ferguson believes the cooling can only work its effect on a minority of chicks which are "near the border line" of the male-female spectrum. The cooling is thought to work by slowing down the operation of enzymes involved in sex determination.The cooling has to be done very precisely. Chickens try to keep their eggs at a steady 37.5C below their body. This is the temperature used in commercial incubators.


I'm not convinced my self.

 

[Mace Gill]

I guess it could be possible??

Nicholas Schoon wrote.
If the temperature is dropped by a few
degrees for three days during the embryological development of a freshly laid egg, some chickens which should hatch out male instead become female.They have the genes and chromosomes for maleness but they are fully functional females able to lay fertile eggs. If they are then crossed with normal males, the resulting chicks are all male, said Professor Mark Ferguson of the University of Manchester.This is what interests the poultry industry.All the female chicks which hatch from the breeding stock which provides the broiler chickens we eat are destroyed after hatching. Only the males put on enough meat, at sufficient speed, to make them economically viable. So there could be large savings if the breeding stock could be made to produce only males.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.Professor Ferguson believes the cooling can only work its effect on a minority of chicks which are "near the border line" of the male-female spectrum. The cooling is thought to work by slowing down the operation of enzymes involved in sex determination.The cooling has to be done very precisely. Chickens try to keep their eggs at a steady 37.5C below their body. This is the temperature used in commercial incubators.


I'm not convinced my self.

interesting food for thought, though

 

[McChooky]

This one says stress causes the flock to have more hens https://www.poultryworld.net/health...re-likely-to-produce-female-chicks/?cmpid=NLC

 

[BigBlueHen53]

Anecdotal: I purchased 16 lavender EE at the end of April this year (2024), 10 turned out to be cockerels. At least in this one incident, the folk wisdom of Estonian Granny was correct. Anyone else want to share their experiences? (This was not the entire hatch however, it just happened to be true of the 16 I got.)

 

[Susan Skylark]

Certain lizards and fish can change sex but I’m pretty sure birds and mammals don’t/can’t! While there may be something in male embryos being more cold tolerant than females (meaning more hatch) that does not mean they switch sex, more of the female embryos die (or whatever the temp thing is). Sex in birds is established at fertilization and doesn’t change due to ambient temperature. Alligators can change sex depending on incubation temp but birds?

 

[McChooky]

Certain lizards and fish can change sex but I’m pretty sure birds and mammals don’t/can’t! While there may be something in male embryos being more cold tolerant than females (meaning more hatch) that does not mean they switch sex, more of the female embryos die (or whatever the temp thing is). Sex in birds is established at fertilization and doesn’t change due to ambient temperature. Alligators can change sex depending on incubation temp but birds?

The study I read shows cold storage around 40 degrees leads to an increase in embryo death and fewer male chicks hatching(more hens)

 

[McChooky]

Anecdotal: I purchased 16 lavender EE at the end of April this year (2024), 10 turned out to be cockerels. At least in this one incident, the folk wisdom of Estonian Granny was correct. Anyone else want to share their experiences? (This was not the entire hatch however, it just happened to be true of the 16 I got.)

One study I read said incubated chicks hatch more cockerels than broody hens which coincides with another study on wild birds altering the sex of offspring(push some out of a nest?)

 

[SweetieChicken234]

Beginning of summer(May 31) I had 19 hatch from my incubator. 6 were cockerels. 3 weeks later my broody hatched 6. 4 of those were cockerels. I guess we are all over the place here.