Fertilization-males vs females ratio

[sonjap]

Hi all, this is my first year having a broody. I thought it would be fun to let her hatch some eggs. I have one rooster and I gave the hen eggs from several other hens as well. 9 hatched and I ended up with 6 roosters and 3 hens. I don't like that ratio too much!
I was wondering if some Roos just have more Y sperm than X's, or was that just how it went this time around. If my hen goes broody again I'm not sure if I want to let her hatch again or if my ratio could be totally different next time.

 

[ChickenCanoe]

Birds are different than mammals in that the hen determines the sex. Instead of XY chromosomes, they have ZW chromosomes - as do some fish, reptiles and insects.
Males are ZZ and females are ZW.
Some interesting stuff on the topic.
http://www.nytimes.com/2010/07/20/science/20chicken.html?_r=0
http://onlinelibrary.wiley.com/doi/10.1111/j.1742-4658.2011.08032.x/pdf
https://en.wikipedia.org/wiki/ZW_sex-determination_system

Normally embryos become male or female at about a 50:50 ratio. Actually it's more like 45:55 but I can't remember which is more heavily weighted.
Out of a dozen eggs, about every 80 times, they'll be all male or all female.

 

[sonjap]

Wow, I had no idea! Thanks for the links!

 

[lazy gardener]

Then, there are a few of us who are experimenting with this issue. I started a thread on the subject this spring, and had what I considered to be a reasonably good outcome: https://www.backyardchickens.com/t/958517/nutrition-and-gender-and-inducing-broodiness