Breeding question about combs

[CountryMom]

How long ....how many generations would it take to breed out a rose comb to a single comb?

And if you have a pea comb crossed with single, what is the likely hood of a single comb popping out when bred back to pea comb?

 

[Sonoran Silkies]

Quote:
Let me understand--first question is changing from rose to single and 2nd is changing from single to pea?

To remove a rose comb will take at most two generations: If the bird has two copies of the rose comb gene, crossed to a single combed bird all the F1 offspring would have one copy of the rose comb gene. Cross those F1 offspring back to a single combed bird and half the F2 birds will be single combed. Cross the F1s together and a quarter will be single combed.

If the rose combed bird carries only one copy of hte rose comb gene, when bred to a single combed bird half of the F1 offspring will be single combed.


Pea comb is a bit more complicated because a recessive can lie hidden for generations. However, pea comb is incompletely dominant, so it is sometimes possible to tell if it is present in a bird in one copy or two than with rose comb.

If you take a P/p and cross it to a P/P, half the offspring will be pure for pea comb and half will carry a copy of not-pea comb. If you breed P/p to P/p, a quarter will be pure for peacomb, a quarter will be pure for not-pea comb (they will be single combed) and half will be split.

 

[CountryMom]

Yes, two different questions. The first is a Orp cross and here is his picture. I have a buff, black, and/or blue hens to cross him with if I wanted to try to work on this coloration. Just looking into the comb questions before I embark on a project of this sort.

And the pea comb one is a Marans X EE Rooster. Possible work on Olive Eggers.

 

[Henk69]

The problem is that single combed animals from your second experiment probably will loose the blue egg gene.

 

[CountryMom]

Quote:
That was why I asked about the comb. I would have to cull out the single comb birds until I had bred it out if that is possible. I wondered if it was like a hiden gene I work with in the guinea pigs. Only difference is I breed to pop out the hiden gene in the pigs which isn't as easy as it sounds.

 

[Sonoran Silkies]

Quote:
That was why I asked about the comb. I would have to cull out the single comb birds until I had bred it out if that is possible. I wondered if it was like a hiden gene I work with in the guinea pigs. Only difference is I breed to pop out the hiden gene in the pigs which isn't as easy as it sounds.

If you cull the single combed birds you will probably keep the blue egg gene. You should probably also cull the birds whose pea combs are too tall (indicating a not-pea comb gene) or those whose eggs are poorly coloured.