Phenotype of Automal Barring (Pg) without Dark Brown (Db)

Discussion in 'General breed discussions & FAQ' started by centrarchid, Dec 28, 2012.

  1. centrarchid

    centrarchid Chicken Obsessed

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    I have chickens with Pg allele that when homozygous in the company of Db/- or Db/Db produces the redquill color pattern. Birds lacking the Db allele have hints of the redquill pattern but base coloration is much lighter (reddish) and down coloration of chicks is very different. Does anyone have pictures showing their birds that are Pg but lack Db? Mine also on wildtype e+ background.
     
  2. centrarchid

    centrarchid Chicken Obsessed

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    Following images part of what I think I know.

    First shows how how full sibling chicks can look at hatch with respect to Pg allele. Note not only are stripes different in width, they differ in how strongly they contrast with surrounding down. Wheaton at E-locus not involved based on Wheaton birds never thrown. Birds not pumpkin since black of flight feathers is not diluted.

    Left is e+/e+ -/- or wild-type
    Middle is e+/e+ Pg/- like both parents were at hatch.
    Right is e+/e+ Pg/Pg
    [​IMG]

    Second shows Pg/Pg cockerel intering first adult feather set
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    Grand father as entering first adult feather set. He is common source from which Pg allele was inherited. He was Pg/- and similar to middle chick at hatch. His body plumage is much darker than Pg/Pg cockerel above.
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    Grandfather as adult.
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    Last edited: Dec 28, 2012
  3. nicalandia

    nicalandia Overrun With Chickens

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    without Db there is no autosomal barring, not on the males atleast, the females may look different than your everyday wildtype e+/e+ pg+/pg+ db+/db+ birds, but a wildtype rooster with just Pg/Pg and db+/db+ will not be restricted at all(black tail red or black tail orange) and Pg is just a pattern gene not a restrictor.


    I dont know any wildtpe based breed with just Pg and nothing else(all other genes wiltype). I dont think this type of breed exist. BUT.. there is the Partridge wyandotte. Partridge Rock breeds which are just eb(eb brown) and Pg/Pg with all other genes been wildtype(except for red enhancers)


     
    Last edited: Dec 29, 2012
  4. centrarchid

    centrarchid Chicken Obsessed

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    Are you considering the lighter coloration chick on right a dilution relative to wild-type? I think it is a restricter or pattern mechanism. Note the chick on rights darker stripe even though it is smaller. A diluter would simply make part or all of down lighter.
     
  5. centrarchid

    centrarchid Chicken Obsessed

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    What other simple system can cause color patterns I am seeing if not Pg? The variations in down coloration I think are key. Phenotypes are 1/4 wild-type, 1/2 intermediate, and 1/4 very light. What genotypes can cause the observed chick down colorations be they patterns or dilutions?



    Note hen below which is mother of chicks above and full sister to sire of chicks. What color pattern would she be classified under.


    [​IMG]

    [​IMG]
     
  6. nicalandia

    nicalandia Overrun With Chickens

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    I´m not considering any chick color at this stage. I was just pointing out that a e+/e+ Pg/Pg db+/db+ rooster will NOT look autosomal red because it lacks the columbian restrictor Db
     
  7. nicalandia

    nicalandia Overrun With Chickens

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    Pg is not a diluter, aside from been a pattern gene, one could also call it a melanizer if you must. but it will not affect the chick or the adult pheomelanin(gold pigment).. your hen seems diluted by other gene/s.. maybe Dominant Dilute Di? does her genetic background has any pumpkin? that could explain a few things
     
  8. centrarchid

    centrarchid Chicken Obsessed

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    No pumpkin involved. Part of genetics required to make a pumpkin may be present but no birds of pumpkin ancestry could have been involved for a very long time and I know range of phenotypes that flock exhibited because I grew up with it and have good knowledge of pedigree within it. These are not birds acquired from a hatchery or some backwoods cocker that allowed hens to be covered by any rooster that fit their fancy.

    The chick coloration is key to figuring out what locus / alleles are involved. Several genotypes can give similar phenotypes in adult male but chicks and juveniles vary big time as a function of genotype.

    What does a proper pumpkin hen look like? What does a proper pumpkin chick look like?
     
  9. centrarchid

    centrarchid Chicken Obsessed

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    Hen I assume to be dark brown Db. This phenotype I no longer have but when bred to roosters looking like the males above, redquill chicks and hens are produced. Males of same that were not redquill as chicks are difficult to distinguish from redquill roosters without scrutenizing individual feathers. Owing to that, we consider all such roosters with red-brown body and black tail to be brown-breasted brown reds.

    [​IMG]


    I am working to acquire another hen (related to my line) that looks like hen above. I assume that if redquill are produced by mating of such with cockerel in second post, that autosomal barring Pg is in fact causing the observed appearance in cockerel and modifications to chick down.
     

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