Quote:
Thank you for the complement!! Here is some information I took from another thread. Im striving for 100% hatch rate rose comb but right now Im about 75% rosecomb. Finding the right hens to breed with the right roo and get good fertility and rosecomb chicks is always a work in progress.
poppycat wrote:
The offspring of the chicks will depend on whether their parents with rosecomb are homozygous or heterozygous
Homozygous means both copies of the gene are the same.
Heterozygous means that the bird has a copy of the gene for both rosecomb and single comb. The rosecomb trait is expressed, but the recessive single comb gene is still passed on.
Heres the first possible cross R=rosecomb gene, the dominant trait, s=single comb gene, the recessive trait
Rs x Rs (heterozygous birds with rosecombs)
25% of the offspring will be RR, homozygous rosecomb
50% of the offspring will be Rs, heterozygous rosecomb
25% of the offspring will be ss, homozygous single comb.
The next cross:
RR x Rs (both with rosecomb, 1 homozygous, 1 heterozygous)
50% of the offspring will be RR, homozygous rosecomb
50% of the offspring will be Rs, heterozygous rosecomb
The next cross:
RR x ss (both homozygous, one with a rosecomb, one with a single comb)
100% of the offspring will be Rs, heterozygous rosecomb
And last but not least;
Rs x ss (heterozygous rosecomb with homozygous single comb)
25% of the offspring will be Rs, heterozygous rosecomb
75% of the offspring will be ss, homozygous single comb.
