what is a homogenous

Discussion in 'General breed discussions & FAQ' started by kelliepulido, Oct 23, 2008.

  1. kelliepulido

    kelliepulido Chillin' With My Peeps

    Mar 18, 2008
    st.john's mi
    Show girl?
     
  2. Kev

    Kev Overrun With Chickens

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    Jan 13, 2008
    Sun City, California
    Homozygous. In the case of Showgirls, it means a bird genetically pure for the naked neck gene.

    Which means if you breed a homozygous roo to pure silkie hens, all of the chicks will be showgirls(naked necks). The chicks won't be homozygous though.

    BTW the term for not genetically pure for a trait is called Heterozygous. As in:

    Heterozygous roo bred to silkie hens: Half showgirl and half silkie chicks.

    edited to add, for the naked neck gene it does not matter which parent has it. Above was only an example- silkie rooster over showgirl hen would give same results..
     
    Last edited: Oct 23, 2008
  3. kelliepulido

    kelliepulido Chillin' With My Peeps

    Mar 18, 2008
    st.john's mi
    how do you know if they are homozygous if you bred a showgirl to show girl
     
  4. kentuckysilkies

    kentuckysilkies Chillin' With My Peeps

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    Birds that are homozygous for the naked neck gene do not have the bow-tie in the center front of neck. Their necks are totally naked or may have only a couple feathers in the front center.
     
  5. fancyfowl4ever

    fancyfowl4ever Chillin' With My Peeps

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    Cranbrook, BC, Canada
    Homozygous - 2 genes
    So the Showgirl has 2 naked neck genes, thus all of this birds offspring will get 1 gene from this bird there for be naked necked.

    heterozygous- 1 gene
    from a showgirl with only 1 nn gene only 50% of its offspring will inherit the nn gene. So crossed with a non-nn bird only 50% of chicks will be nn, but if crossed with a homozygous you get 50% homozygous nn and 50% heterozygous nn chicks, and if crossed with another heterozygous you would get 25% homozygous nn, 25% w/o nn gene and 50% heterozygous nn.

    I Hope this makes sense.
     

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