question on genetics feathered shanks naked feet silver hmong

[gojira]

haha yes... z w mammal bias showing... no i do not mean incomplete dominance in the BBS way... alleles of course code for proteins/enzymes that do certain things... often there is a threshhold that must be met before a result occurs... there can be any number of alleles coding for a particular protein with different levels of efficiency... two alleles may be additive ... so the net result is the sum of efficiencies... the BBS system is very simple of course but many traits are not discrete and involve dozens of genes... my example was a hypothetical relatively discrete mendelian model that approaches quantitative inheritance.... if 1.5 units are needed to get feathers... one allele (dominance) is only enough if its the stronger allele.... the 2.0 rather than the 1.0.... but 2 1.0s would express as well.... i am NOT saying this is real... just possible... the literatire on stubs also stated that quantitaive inheritance may well be involved...

Anyway, you are right the cleanest approach would be to cull all stubs... BUT relying on 2 birds to rebuild a population may be throwing he baby out with the bath water... i still think in would rather use the two extra birds and then work to be rid of the stubs from a larger gene pool

I was not saying it was incomplete dominance. I was trying to figure out what you meant by partial dominance, as that is not correct terminology. If you are talking quantitative traits, dominant and recessive do not apply. Explaining that would take up a lot of space. I would still breed only birds without feather stubs, if I bred any at all. Your birds may all be siblings anyway, so it does not make much difference if you use 2 or 4. You won't get rid of feather stubs if you use birds with them.

 

[goedric]

I was not saying it was incomplete dominance. I was trying to figure out what you meant by partial dominance, as that is not correct terminology. If you are talking quantitative traits, dominant and recessive do not apply. Explaining that would take up a lot of space. I would still breed only birds without feather stubs, if I bred any at all. Your birds may all be siblings anyway, so it does not make much difference if you use 2 or 4. You won't get rid of feather stubs if you use birds with them.

Yikes... i guess i was confused.... when i was working on my PhD in quantitative genetics at the University of Chicago....

(1) partial dominance... incomplete dominance... and semi-dominance.. were used more or less interchangeably

(2) Dominance was an critical complicating factor in quantitative genetics.

(3) The gene pool from 4 sibs was much more diverse than the gene pool from 2 sibs.

Guess I was a bad student... it's a wonder they published my work in the Journal of Evolution.. and some other places

Thanks for your input

 

[Pyxis]

I agree with feather stubs, but i disagree that it is not associated with the feathered leg genes. Every instance of feather stubs i have seen, going back nearly 35 years, has been associated with birds with feather legged breeds in their ancestry. A few years ago I saw a Buff Orpington from an exhibition line with fairly heavy feathering on her shanks, out of clean legged parents, and how long ago was Cochin in the breeding of Buff Orpingtons? I have seen it in Rhode Island Reds, and have seen pictures posted of New Hampshires with feather stubs. I have seen it in other breeds, including bantams, but every case has been a breed with feather legged birds in the ancestry.

I've had feather stubs on a duck before. There are no feather legged duck breeds. Of course it would be different genes in chickens and ducks causing them, I just thought it was interesting.

What I had meant with my comment about it being not related to feathered legs is that it is definitely not the normal dominant gene for leg feathering. There is a recessive gene for leg feathering, but that is much more rare, and I don't think is the gene that causes feather stubs either.

Are there feather legged breeds in the Ameraucana's ancestry?

 

[Ravynscroft]

Are there feather legged breeds in the Ameraucana's ancestry?

Nope, there absolutely isn't... and stubs have cropped up in several lines...

I have also gotten feather stubs on a couple of my ducks as well... and seen another member with a Rouen duck that had feathered legs...

This is a recessive trait, while the more known feather-legged traits like in Cochins and Marans is dominant...

 

[Pyxis]

Nope, there absolutely isn't... and stubs have cropped up in several lines...

That's what I thought. As far as we know, ayam cemanis don't have feather legged ancestors either, but they still can hatch with feather stubs.

 

[Ravynscroft]

That's what I thought. As far as we know, ayam cemanis don't have feather legged ancestors either, but they still can hatch with feather stubs.

Agreed... and out of clean legged parents... there have been other breeds that have had feather stubs crop up too... I did some research a while back, but I'd have to look up the links again, that explained this odd recessive trait... and that it is completely separate from the dominant feather-legged trait...

 

[goedric]

hmmm with the possibility of it being a recessive trait... may be a good idea not to breed the ones who express cause it could be a bugger to get rid of. From what I have read the Hmong birds are a melting pot of bloodlines... so the strait could have come from anywhere... they are discussed on the Asil boards... and i read that much of the stock in the states came in the 80s... This breed certainly has more visual appeal with clean legs... guess i will set those aside at least depending on gender maybe cross them separately just to see what happens... while researching i came upon a fascinating article on the origins of the fibro gene that mentions h'mong... they concluded it predates the domestication of chickens... is the same in all breeds studied... and likely originated with red jungle fowl... is identical in silkies and very interesting article... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381777/