Super stupid question....

[lazy gardener]

Phew, after the snide comments yesterday directed at me and also the general BYC-er, I was beginning to wonde if the love of learning was absent in poultry owners. I posted an interesting (to me) article on rose comb genetics a week or so ago. Two genes for rose comb, R1 and R2. Homozygous R1 can lower fertility in roosters, , R1R2, R1r and R2r (r is wild type single comb) roosters are normal.
How does this belong in a thread on linebreeding? Linebreeding doesn't add genes, so if you started off with an R1r rooster eventually you may end up with single comb and possibly a reduced fertility rooster. Reduced fertility might not be noticable in a backyard flock or small set up.

But two genes for what was originally (long long ago) a mutation? Awesome

I read your post, and was delighted with the info, though, i was not able to figure out your R's and numbers. Homozygous, means that the organism carries 2 dominant genes for a trait, while Heterozygous means that the organism presents the trait, while carrying a recessive gene, right??? So are the R1 and R2 both required to produce a rose comb? I think after reading through all of your R's, r's and 1's and 2's again, I'm wrapping my head around it. I need a teacher. Ignore the snide. Us geeks need to stick together and feed the need. Does this info translate into breeding info for crossing pea and rose???

 

[tridentk9]

I read your post, and was delighted with the info, though, i was not able to figure out your R's and numbers.  Homozygous, means that the organism carries 2 dominant genes for a trait, while Heterozygous means that the organism presents the trait, while carrying a recessive gene, right??? So are the R1 and R2 both required to produce a rose comb?   I think after reading through all of your R's, r's and 1's and 2's again, I'm wrapping my head around it. I need a teacher.  Ignore the snide.  Us geeks need to stick together and feed the need.  Does this info translate into breeding info for crossing pea and rose???

Hang on-my local vet school had a good article that should help. And I'm sorry- I try to explain in the the beginning what's going to happen later but I must have still been lacking sleep. Looking back I see I goofed and didn't put in a code. Thanks for catching that.

Homozygous means the two genes are the same. Recessive or dominant doesn't matter for that term. Heterozygous means the two genes are different. If you have a simple recessive trait where you need two copies of the recessive for it to be seen and there are no modifiers-genes that can change how the trait looks but doesn't change the trait. If the dominant trait is showing up you don't know if you have one or two copies of the dominant gene, they both look the same. It can be homozygous (2 copies of the gene) or heterozygous (1 copy of the dominant gene, one copy of recessive) but you just don't know.


http://www.extension.org/pages/6536...backyard-flocks:-an-introduction#.U9GPqX_n_mw

OK- it explains some of comb genetics on that site. Where it says rose comb is R (capital R because it's the dominant gene) - it can be either R1 or R2. It doesn't matter as far as the comb, either one gives the same rose comb. it only matters-as far as currently known- when you're talking about sperm and even then only when it's R1R1- doubled up on the R1 gene, no R2 and no r (recessive single comb). There isn't enough room for more genes. Well unless avian's can get their own version of Kleinfelders- but that's a whole 'nother story

Now there are more than simple recessive, you can have additive (needs a certain number of related genes for the condition to show), oh drat- let me find fuzzy eyeballs. He did a good job of explaining it. Remember though-there are some differences between dogs and birds- but not really. Confused? It's just using a different accent. You can understand each other but some words have to be explained. Once explained there is a comparative word or example. The rules are the same though.
Now let me find fuzzy eyeball

 

[lazy gardener]

Thanks so much for that article. Nice explanation of Pea x Rose combs. That was one that i was trying to figure out. Also, nice explanation of the reason why barred and cuckoo (?sp) patterned birds can be sexed by shank color. Have you played around with breeding to tinker with your flock??

 

[tridentk9]

Have you played around with breeding to tinker with your flock??

Except for my surprise chick(Dominique cockerel) all should be pullets. The Dom will leave one way or another. Three crevecoeurs and the rest black cochins. I have no plans to breed any of them, they're hatchery chicks. I have no problems with anyone breeding hatchery chicks, in fact I wouldn't be the least bit surprised if the offspring would be better than the parents especially after a few generations. It would show you how much of a difference better food and a more relaxing life would improve the birds. It may show epigenetics at work, it may be just an improved life allowing their chicks to grow to potential. Anyway, I only have so much space and hate dealing with selling live animals to people I don't know. Add in biosecurity ingrained in me after working with parrot breeders- so nope, I have no plans to breed poultry.

And that's why I'm not qualified to discuss poultry genetics no plans to breed poultry. LOL.

 

[lazy gardener]

Well, feel free to discuss anyways, even just for academic purposes... tickles the cranium.

 

[tridentk9]

Well, feel free to discuss anyways, even just for academic purposes... tickles the cranium.

Ahh that's right- the kindle burped when I was writing last night.
Hairy eyeballs not fuzzy- hairy.

http://www.dogstuff.info/importance_of_complete_pedigrees_kral.html

http://www.dogstuff.info/phenotypic_kral.html

http://www.dogstuff.info/multiple_gene_traits_kral.html

The link for the second part is broken, I'll try to find a copy.