chicken comb calculator needs more alleles / loci

Discussion in 'General breed discussions & FAQ' started by centrarchid, Jun 21, 2011.

  1. centrarchid

    centrarchid Chicken Obsessed

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    I have a project involving crosses of dominiques and American games. Dominiques females are homozygous p+/p+;R/R (no pea comb; has rose comb) and males are one game homozygous p+/p+;r+/r+ (no pea comb; has single comb) while second game I thought was heterozygous for pea comb (P/p+; r+/r+). First has sired rose comb offspring only while second is throwing about 50% rose comb and 50% something that is not rose comb, pea comb or walnut comb. According to chicken comb calculator the second bird should have produced rose comb p+/p+; R/r+ and walnut comb offspring p+/P;R/r+. Got none off second phenotype. I do not think what I thought to be pea combs in my "pea combed" games are pea combs. Homozygous form is assymetrical with a lot more size than typical of Aseel games from which the pea comb in my games supposedly derived. They heterozygote looks almost intermediate between pea and single comb.

    Is it possible another allele exist at P locus that codes for a different type of comb? Another locus that codes for another type of comb and over ride r locus for single comb?
     
  2. Henk69

    Henk69 Chillin' With My Peeps

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    You know you have to post a picture now... [​IMG]
     
  3. centrarchid

    centrarchid Chicken Obsessed

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    Game roosters used represented by two phenotypes. First rooster was typical of single comb now dubbed so photo not available. All offsrping he has thrown by a dominique hens have been rose combed. Second rooster (sire of interest below) based on siblings, his sire and dam, and offspring by a single comb female game is heterozygous for single comb and what I have been calling pea comb. Homozygous version (not shown as all dubbed) of pea comb pitched more forward and much assymtrical (laying over to one side).

    Sire
    Lateral aspect
    [​IMG]
    Front aspect (notice strong assymetry)
    [​IMG]

    Desired result - rose comb
    Lateral aspect
    [​IMG]
    Front aspect
    [​IMG]

    Alternative result - looks like single comb when small but with too many points and will be thicker as bird matures
    Lateral aspect
    [​IMG]
    Front aspect
    [​IMG]


    Sire at about 4 weeks older than offspring are now.
    [​IMG]
     
    Last edited: Jun 22, 2011
  4. Henk69

    Henk69 Chillin' With My Peeps

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    assymetrical is just floppy.
    Single combs can have a lot of indentations, still called a single comb.
     
  5. centrarchid

    centrarchid Chicken Obsessed

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    Quote:We shall let this thread rest until fall when cohort of games coming up can be used to illustrate two morphs. I work with morphological variation in natural populations, impart using such variations for taxonomic purposes. Many times variations subtle and require many individuals to demonstrate. Also been keeping this line of games too long not to have noticed the comb types.
     
  6. centrarchid

    centrarchid Chicken Obsessed

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    FOund a difference between my "pea comb" and true single comb. Latter the connection between comb and head goes along entire length of comb with most posterior attachment behind eyes. "Pea comb" posterior limit of attachement anterior to eyes. Saw this on sire and uncles of rooster photographed above. Both types represented. Showing same pattern in 1/2 red jungle fowl sired by rooster above will nail it. Comb type is not a true pea comb either.
     
  7. centrarchid

    centrarchid Chicken Obsessed

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    Images not perfect but showing two morphs produced by crossing red jungle fowl (homozygous for single comb) with American game (heterozygous for flag and single comb alleles).

    Single combLateral
    [​IMG]
    Dorsal
    [​IMG]


    "Flag" combLateral
    [​IMG]
    Dorsal
    [​IMG]
     

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