1. nevergiveup

    nevergiveup Out Of The Brooder

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    Feb 19, 2014
    I have a naked neck rooster and 7 naked neck hens. They are not pure naked necks. I imagine they have been crossed with whomever many a time. I only have NNs, no other chickens. I was graced with 4 chicks this past year. Only one of them has a naked neck! I thought NN was the dominant gene so even if a half NN mated with another half NN they would all have naked necks. Can anyone explain? Thank you!
     
  2. IceAngel

    IceAngel Chillin' With My Peeps

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    I am not knowledgeable about chicken genetics or naked necks, however, when discussing simple dominant genetic traits you will not be able to tell the difference between a homozygous (purebred NN) and a heterozygous (hybrid Nn). If naked neck is dominant all the chickens will appear to be naked neck on the outside. It appears to me you bred hybrids (Nn) in which case 1/4 will be purebred (NN) 1/2 will be Hybrid (Nn) and 1/4 will be pure for the recessive trait (nn).

    These percentages are just statistical predictions. The more offspring you have the closer to the percentages you will get. Here is a Punnet square how I got the percentages. Goggle punnet squares for an explanation of the procedure I used.
    [​IMG]
     
    Last edited: Nov 4, 2015
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  3. nevergiveup

    nevergiveup Out Of The Brooder

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    Well my experience would sure support what you've just said. Looks like i need to find a a homozygous naked neck rooster if i want naked neck babies. Thanks IceAngel
     
  4. Kev

    Kev Overrun With Chickens

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    IceAngel gave an excellent answer. It does sound like at least your rooster and at least one hen are not pure for the NN gene. With that pairing, it is true to expect 75% naked neck chicks but it is not impossible to get more than one non-naked neck out of 4..

    It's like how you are supposed to expect half roosters and half hens but in a small clutch it very easily can run either all pullets or all roosters.. or just one of a sex.

    I'd also like to add if your are from a hatchery or have single combs, it is easy to tell which birds are pure or not pure for the naked neck gene. The pure ones either have totally bare necks or just a tiny bowtie thing on middle of neck with only a few feathers in it.

    The not pure ones have more of a bib thing, with lots of feathers that cover a lot of the neck.

    The mother hen and the chicks are not pure for naked neck, lots of feathers/fuzz on their necks:

    [​IMG]

    and this young boy pure for NN has an very naked neck with jsut few feathers:

    [​IMG]
     
  5. varidgerunner

    varidgerunner Chillin' With My Peeps

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    One of your naked neck chicks could be homozygous. Breeding them to a non naked neck would tell you.
     
  6. draye

    draye Overrun With Chickens

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    [​IMG]

    Here's my up and coming double naked necked genes rooster.

    He was bred for the mottled project but as far as I can tell he isn't going to have the mottling, but should be a carrier for it.

    I know that any NN hen he is bred to all chicks should be NN'd.
     
  7. IceAngel

    IceAngel Chillin' With My Peeps

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    Yes one of her Naked necked chicks could be homozygous ....but breeding it to non naked neck will produce only naked necked hybrids which she will not be able to distinquish from homozygous naked necks, if Naked neck is the dominant gene. If she ever gets one non naked neck chick out of the match then that is a clear indication that the original chick was not homozygous. See the following Punnet Square
    [​IMG]
     
  8. IceAngel

    IceAngel Chillin' With My Peeps

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    If you can tell the difference visually between a pure naked neck and a non pure naked neck then this is not a case of a single, dominant gene. Something else is going on.....either it is a degree of incomplete dominance or more than one gene is involved.
     
  9. Kev

    Kev Overrun With Chickens

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    No it's pretty simple. The reality is there are not that many truly 100% dominant genes. The genes don't care about human fondness for clear definitions so we pretty much have to accept definitions that are not so crystal clear. How much of a degree of expression is acceptable to fall under dominant vs incomplete, that is something there won't be universal agreement on.
     
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  10. IceAngel

    IceAngel Chillin' With My Peeps

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    You are right Kev, there are not as many single genes that confer dominance than factors that are polygenic. You are also right that humans try to simplify things for the sake of explanation. However, something is either dominant or it's not dominant. If you have degrees of the factor then chances are more than one gene is involved which are modifying the factor. There are also cases of gene mutations where portions of the amino acid code has changed just enough to change the protein ever so slightly. These mutations can also modify the factor and are inheritable. I don't know anything about the No Naked Neck gene(s) but I do know Genetics on a molecular level.
     

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