Cream Legbar Working Group: Standard of Perfection

[KPenley]

A question to the SOP experts(still learning and trying to carefully study it) what does the SOP says about feathering on the Thighs? I have seen many that have seen Males with very soft featheing on them, also what does it say about the Barring on them, this is where I see the blured out barring pattern on the entire bird on most males here..

Not necessarily an expert...

This is one of those areas that is not defined in most PCGB or APA standards. The male only has "Under-Color of All Sections: Silver-gray." listed in the color section. The female has "Body and Fluff: Silver-gray, indistinctly barred." in addition to the "Under-Color" description listed in the color section. We went back and forth on whether to add the "indistinctly barred" to the male, and only did not because we were trying to follow the patterns and formats represented by other breeds in the APA SOP.

 

[nicalandia]

Quote:
oh I see, some males do show this indistinctly barred pattern, which is not clear barred pattern but a blured barred pattern

 

[KPenley]

I meant to write "not defined".

 

[nicalandia]

Quote:
I understood it that way... here is a Drawing one could use to learn the different parts of the males areas

 

[tadkerson]

hi nicalandia -

reading in Sigrid's book on genetics - the closely barred BPRs are E based and the Cream Legbars are e+ - This means, to my understanding, that the feather growth is different, and there are different undercolors as in the duckwing/wild type/partridge pattern and CLs will never (and because they are e+ based) show the BPR type of barring. And we wouldn't want that type of barring because the e+ chipmunk stripes are part of the ease of autosexing - and all of us would probably prefer good autosexing over tidy barring. ETA the barred leghorns could and probably are E based and not e+. Sigrid states that any e+ barred bird will be a Crele not a (in Europe cuckoo/in the USA barred). There is even a Crele orpington called the "Legbar Colored Orpington"....and also Crele Orpington.

The mono-colored birds preferred in the UK as some of the examples you showed many posts ago - also may be partially why the UK is "loosing autosexing" as this UK website mentions.

http://poultrykeeper.com/chicken-breeds/legbar-chickens

Unless changed since I originally encountered that website, "many Crean Legbars have lost their autosexing qualities." --( The paragraph right before BOOKS at the bottom. )

Genetics 101

The E locus allele products (membrane proteins) are either constitutive or inducible. The extended black allele's product is a constitutive membrane bound protein. This protein is constantly switched on so that the cell is always in a black pigment producing mode. There are mechanisms inside the cell that regulate the amount of black pigment that can be added to a feather. So the production of black pigment can be regulated at the cell level. The inducible membrane proteins ( wild type) are dependent upon melanocortin binding on the protein and setting into motion the production of black pigments.

Extended black product ( membrane protein) is always turned on while the wild type product (protein) is turned off unless a melanocortin binds to the wild type protein. If the wild type protein is not bound by melanocortin the cell produces red or brown pigments or no pigments ( other mechanisms in the cell turn off the red or browns) in the case of white ( a bar).

To get good crisp barring the black pigment must be switched on and off quickly so the whole barring mechanism is finely tuned to produce or not produce black pigments; no lag time or intermittent black pigment production.. The constitutive proteins can be easily and quickly switched on or off at the cell level. The wild type allele is dependent upon the melanocortin floating around in the blood and the mechanisms inside the cell to be turned on or off so you get a sloppy bar; lag time and intermittent black pigment production.

I believe there are other factors (genes or promotors) that can effect barring but I believe the correct E locus wild type allele will go far in producing better barring.

Those are my thoughts on the process.

The trick is finding the right wild type allele. So this all means if you find a male with good barring it is most likely not a fluke but genetic and the trait can be passed on to the offspring.

Also if the male gets whiter with age ( less distinct barring) that can be expected because the levels of tyrosine drop in older birds. Tyrosine is needed to make pigments black or red.

Recent research shows that there is polymorphism ( different forms) in the wild type alleles. This could account for differences in the barring in wild type birds. My hypothesis is that the birds with the best barring are producing a constitutive product so the barring is better.



Poult Sci. 2010 Jun;89(6):1110-4.
Developmental phenotypic-genotypic associations of tyrosinase and melanocortin 1 receptor genes with changing profiles in chicken plumage pigmentation.


Anim Genet. 2003 Aug;34(4):241-8.
Melanocortin 1-receptor (MC1R) mutations are associated with plumage colour in chicken.


Br Poult Sci. 2010 Dec;51(6):734-9. doi: 10.1080/00071668.2010.518408.
Genetic variation of chicken MC1R gene in different plumage colour populations.

Recent research also shows that the system (MRC1) that is responsible for black pigment production is less active in older birds so you will get more white in older birds.




Tim

 

[lonnyandrinda]

Excellent, thank you Tim!

 

[nicalandia]

Quote:
Thanks Tim, I was also thinking that way too, but I was off as to believe it was the Barring gene and not the e+ allele,

 

[ChicKat]

Genetics 101

Thanks Tim! sign me up for the Genetics 101 class....

...so "good barring" is inheritable; depending on which e+ allele the offspring get... Is 'good barring' in the chicken world considered the most regular and closest to symmetrical?

For my own Cream Legbars - they have gone through several color changes - actually darkening after this molt (but I was stuffing them with beta carotene to fight an infection - which may have added to the red they are now showing)---- So with age instead of lightening they have darkened.



This is the same rooster that is in my avatar, and third one in the series that nicalandia posted some posts back is now very dark on the breast. It's windy and getting very cold out and they wouldn't stand still- but I think this shows the color contrast petty accurately, It is regular, wide and somewhat indistinct barring, but definite barring - not crisp like a BPR

Here is a close up of his hackles - and I have always thought that the barring was very 'fine' and very regular, but too much black --


And the whole picture:

With apologies to the taste of "cream = silver-looking" people since I beg to differ, I love how he looks, and his comb has straightened, he has the right number of points - his crest has filled in and relaxed to a neat - rather than David Bowie look - his tail is at 45-degrees and someone today was just remarking to me how great those white sickle feathers look - but I know he is going to loose them before long - because they always eventually fall off, then regrow. He is cashing in on all the 'some chestnut allowed' that he possibly can....lol I think he is pretty much done with his molt...and love the look for such an old guy (2-years) Didn't get good pictures but at least there is no harsh sun to blast out the light colors...

So - Tim, as he ages, he will lighten, like the dogs that get gray muzzles and around the eyes, and equines - and humans loosing pigment in hair - That is a sign that he will be getting old?

One more request for you Tim,....regarding the in-depth egg shell article you wrote, I meant to send the great egg article to someone that was on a French site...translated to English -- but I don't kow where the link is...It needs to go into that thread about getting genetic testing (DNA sequence for our chickens) .

I hate when a link or a post is somewhere in BYC threads that you posted about in the past...

 

[nicalandia]

Quote:
now that you mention the Crele OEG, which males based on e+/e+ and B/B, they have the dark gray distinctive evenly barred, well defined outline.. here a OEGB showing us his SOP beast

now BlackBird's rooster showing one of the most distinctive breast I have seen so far, but still lacking some evenness on the pattern..

now to what I see most often, an uneven grey pattern birds and also lacking the contrast between White and grey, some males show very light gray or gryish white areas where the white should go and light gray/gray areas where the dark grey should be therefor blurring the lines and making it look uneven and unorganized.. you can see this from cockerels up to roosters..

 

[CibolaChooks]