Blue eggs a virus?

Discussion in 'Chicken Behaviors and Egglaying' started by Sassyalice, Sep 14, 2013.

  1. Sassyalice

    Sassyalice Hatching

    Sep 5, 2013
    Just getting my girls today and was wanting to get some layers that have blue eggs.. this caught my eye... I find things like this interesting.

    Here in the U.S., our eggs mostly come in two colors: white and brown. But there are two breeds, one in Chile and one in China, that are known to lay blue eggs. Yeah, weird, right? And a new study has figured out why that happens.
    The Araucana chicken from Chile and the Dongxiang and Lushi chickens from China (none of which are particularly common in North America) are known to lay pale-blue eggs. This is rare for a chicken; while bird eggs can come in all sorts of colors and patterns, chicken eggs are almost always white or brown. So what's the deal?
    A new study found that a single gene, called callee oocyan, is responsible for the odd coloration of these blue chicken eggs. But how did it get there? Turns out that these chickens have a high incidence of a particular retrovirus, called EAV-HP. Retroviruses are a type of virus that integrates its own genetic data into the host in an unusual order. Instead of transcribing DNA into RNA and then into protein, retroviruses operate backwards, retroviruses have RNA, which they use to make DNA, and then integrate that DNA into the DNA of their hosts. HIV is probably the best-known retrovirus.
    This EAV-HP retrovirus is responsible for inserting that weird gene, the one that turns the chicken eggs blue. Specifically, it changes the chemistry of the eggshell so that it can take in biliverdin, a bile pigment, from the chicken's uterus. Weird! And not necessarily harmful; blue eggs are widely eaten and the Araucana, in particular, is a very popular exotic chicken breed. But now you know why their eggs are blue!​
  2. donrae

    donrae Hopelessly Addicted

    Jun 18, 2010
    Southern Oregon
    I have no idea if their science is correct, but Easter eggers are pretty much a dime a dozen here in the US. Blue or green eggs aren't really that rare at all. I really never thought of it as that weird, some wild birds lay blue eggs, why not chickens?

  3. Cindy in PA

    Cindy in PA Crowing

    Jul 8, 2008
    Fleetwood, PA
    I was told there are only too true colors of eggs white & blue. A white egg has white on the inside of shell. A blue egg has a blue inside shell. A brown has a white inside shell, so who knows?
  4. A.T. Hagan

    A.T. Hagan Don't Panic

    Aug 13, 2007
    North/Central Florida
    The link to the Virology Blog the PopSci article was developed from:

    As I am reading this a retrovirus originally inserted the gene that causes blue eggshells. The gene is then reproduced as chromosomes divide in the usual way. It is my understanding that we are finding viral modification of our DNA (and everything else's DNA) at some point in our specie's past is much more common than we ever believed before.
  5. WalkingOnSunshine

    WalkingOnSunshine Crowing

    Apr 8, 2008
    Science knows!

    The brown part of the egg's color is a color put on over top of the shell as the egg is being laid. On BYC, it's almost always described as being like an inkjet printer, but of course that's just a saying. So your brown egg is a white egg with a brown coating put on top. A green egg is a blue egg with a brown coating put on top.
  6. Sassyalice

    Sassyalice Hatching

    Sep 5, 2013
    We had a doozy of a storm last night. I noticed an egg that one of the girls dropped in the open had lost some of its colour when I was out collecting there this morning.. Like the brown had been partially washed off. Cool.
  7. urbancabin314

    urbancabin314 Hatching

    Nov 25, 2013
    so, just to clear up any confusion for me, Is the retro-virus that makes the egg shells blue dangerous at all to the chicken or to whoever eats the egg?
  8. lazy gardener

    lazy gardener Crossing the Road

    Nov 7, 2012

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