Consistently hatching more males than females

[JacinLarkwell]

how could genetics produce anything other than 50-50 male-female on average?

Just like humans, some individuals produce more males than females or more females than males.

 

[Perris]

Just like humans, some individuals produce more males than females or more females than males.

but what's the genetic basis for it? Just like you can get say, 4 heads in a row (or 4 tails), so you could get 4 boys (or girls). How could it work at a genetic level?

 

[JacinLarkwell]

but what's the genetic basis for it? Just like you can get say, 4 heads in a row (or 4 tails), so you could get 4 boys (or girls). How could it work at a genetic level?

By consistently having more of one sex hatch from that hen.

 

[Perris]

By consistently having more of one sex hatch from that hen.

can you explain the cause rather than relate the effect?

 

[NatJ]

Are they all sired by the same rooster?

In chickens, and all other birds, the female determines the gender of the offspring. Yes, that is backwards of what we all learned in school about mammals.

https://en.wikipedia.org/wiki/ZW_sex-determination_system

 

[NatJ]

but what's the genetic basis for it? Just like you can get say, 4 heads in a row (or 4 tails), so you could get 4 boys (or girls). How could it work at a genetic level?

It appears that some female birds do produce uneven sex ratios, and scientists are still working to understand how.

Here's one article that discusses a possible mechanism, and a quote from the article:

https://news.cornell.edu/stories/20...ther-birds-find-way-produce-more-progesterone
"Cornell University researchers think they understand the mechanism that several bird species use to bias the sex ratios of their offspring toward female.

"By experimenting with domestic chickens, they have determined that the presence of higher-than-normal levels of the hormone progesterone during the first meiosis -- the cell division that divides the sex chromosomes and genetically determines the sex of an offspring -- produces significantly more females. "

 

[PeepingK]

maybe they can set up a little bachelor pad for the roos! if there are no hens they can all live together pretty harmoniously

They aren’t allowed roosters where they live

 

[raingarden]

I don't know how it works, but in humans the tendency to have offspring of one gender is a heritable trait.

 

[PeepingK]

My hatch from this year was 6 males out of 7, so I can sympathize.

It sucks… so far I haven’t gotten a single hatch that comes anywhere close to being 50/50. And each hatch I do seems to get progressively worse (more and more in favour of cockerels).
I just did another hatch yesterday and all 5 of my Back cross Olive Egger (BCM x silverrudds blue) and all 5 of my f1 Olive Eggers (BCM x silverrudds blue) are all wing sexing as male… I know that looking at pin feathers isn’t supposed to be accurate but it was bang on the last hatch. If all 10 of those chicks do turn out to be male then what are the chances of that happening?? The eggs that I hatched were only from 2 hens, so 5 from each.

 

[JacinLarkwell]

can you explain the cause rather than relate the effect?

No. Just what I've observed with my giant hatches I've had with my flock. So.e females consistently hatched more males or more females. I had one female that out of dozens of chicks she hatched, there were less than 5 males