I was reading in an old book, "The Poultryman's Guide" by Quisenberry, no copyright date but probably printed in the early 1900's, that...
"if you mate a strong, active cockerel with hens that are two to five years old, using about 25 or 35 hens with one male bird, you will hatch from 75 to 90 per cent cockerels. To raise nearly all pullets, use an old male bird with 25 or 35 good pullets. You may not have the highest average fertility, but the chicks hatched will run largely to pullets. You will get best results if these birds are allowed to have free range."
Just an interesting notation that made me scratch my head. I have no idea of the truth of this, but something prompted this guy to include this in his book....this was about the time they were promoting using mercury for medicinal purposes, too.
Kinda strange, but...?????
Ed
"if you mate a strong, active cockerel with hens that are two to five years old, using about 25 or 35 hens with one male bird, you will hatch from 75 to 90 per cent cockerels. To raise nearly all pullets, use an old male bird with 25 or 35 good pullets. You may not have the highest average fertility, but the chicks hatched will run largely to pullets. You will get best results if these birds are allowed to have free range."
Just an interesting notation that made me scratch my head. I have no idea of the truth of this, but something prompted this guy to include this in his book....this was about the time they were promoting using mercury for medicinal purposes, too.

Ed