Id/Id vs. Id/id+

Posted by: Anonymous

Id/Id vs. Id/id+ - 09/05/03 08:31 PM

I would like to find out if my bird is homozogeous or hetero for Id. Do Id/Id shank color look identical to Id/id+ (or is there some kind of "dosing" that lightens Id/Id from Id/id+?

Here's a pic of the chick taken months ago (sorry, not a good pic but my best at this time), the white marans chick. There appears to be a slight silvering to the front of the pink shank.
http://www.backyardchickens.com/galleries/musaland/chicks3w.jpg

Also, I assume it has E and W+ since the parents are cuckoo marans.

And the bird, months after that photo, now appears certainly female, so I assume sex-linked Id will pass to the male offspring. So if hetero, then half the male offspring will get Id.

Eventually, I would like to breed out the id+. Is there any blood/lab tests to identify id+ in the bird? Thanks much!!!
Posted by: R. Okimoto

Re: Id/Id vs. Id/id+ - 09/06/03 07:27 AM

You have to be careful in trying to determine where the black pigment is. If the pigment is in the epidermal region (outer skin and scales) it is not due to dermal melanin id+. The dermal melanin is the black pigment just under the skin and scales it is the dermis not the epidermis.

Birchin and extended black as well as the eb allele often put pigment in the epidermis of the shank.

That said Id is sometimes not completely dominant. Hybrid males (Idid+) sometimes have noticable amounts of pigment in their dermis.

Genes like wheaten, mottling, dominant dilute, dominant white, and sex-linked barring are known to dilute shank pigment.
Posted by: Anonymous

Re: Id/Id vs. Id/id+ - 09/06/03 01:57 PM

The very slight shading on the shank front is as if the dilution from sex-linked barring was almost doubly diluted. Don't know if wheaten, dominant dilute, etc. are in this bird to do the further dilution.

Dr. Okimoto, thanks much. Just trying to eliminate dark shanks from future breeding possibilities. The French marans website indicates that dark shanks do pop up in white marans breedings (not desireable).
Posted by: KazJaps

Re: Id/Id vs. Id/id+ - 09/06/03 09:58 PM

I have recessive white Orpington bantams which come from my Blues/Blacks. The White Orps are to have the white/pink feet also, but my White Orps have bluish legs (more than likely due to E or ER genes, as the day-old white chicks have patchy blue/white feet).


Above: Recessive White, Blue & Black Orpingtons, all E (extended black) or ER (birchen) & White skinned (W/W).

The above recessive white bird may also be blue (Bl/bl) or Splash (Bl/Bl), but haven't tested him. I have a younger white cockerel that has lighter blue legs. Kind of hoping I'll get Recessive White/Splash birds with only slight hint of blue. Otherwise it's a hard slog to get the correct leg colour.

Musaland, your quest for white-legged White Marans is much easier, considering your whites are from Cuckoo. It should be easy to obtain if the white roos are homozygous for sex-linked barring (B/B), although the hens may have a hint of colour, as can only have one dose of the Barring gene (ie hemizygous). Is the Cuckoo father of the white chicken, homozygous for sex-linked barring (B/B), ie Light Cuckoo? If he is heterozygous (B/b), the white pullet may possibly be non-barred (b/-) & show more melanin on the legs.
Posted by: Anonymous

Re: Id/Id vs. Id/id+ - 09/07/03 06:45 AM

Thanks Kazjaps. The pics are great. Unfortunately, I don't know the color of the parents since I bought the eggs (from a cuckoo marans breeder). The breeder does get some white marans but with dark shanks. It was a surprise when my egg hatched a white marans w/ pink shanks.

I've seen pics of another person's white marans chicks with nice pink shanks. That person indicated that the hen was darker cuckoo. Not certain of the roo.

Good luck w/ hatching a pink shanked white orp.

I'll breed my white to a cuckoo. Hopefully will get nice pink shanks. But I was considering later breeding to a darker shank marans, birchen or brown-red (to try for darker brown egg producers). Concern was for losing pink shanks. Seems very possible. Thanks again.