Gynandromorph Chicken

[tadkerson]

Quote:
Paul,

Normally every somatic cell (body cell) in a mammal is genetically male or female; this excludes sex cells. The xx chromosomes and xy chromosomes determine the primary sex characteristics (genetalia) found in a mammal. It is the secondary sex characteristics that are determined by sex hormones. The same is true in the chickens somatic cells; female cells are normally genetically ZW and male cells are ZZ. In chickens, the presence of female hormones cause female feathering and the lack of female hormones cause male feathering.

Your bird appears to be 100% female. It does not have male feathering on one side and female feathering on the other. If the female layed an egg that means it has a functional overy ( normally chickens have only a functional left ovary) which would prevent the male feathering on one side. You would have to analyze ( do a karyotype) the chromosomes on both sides to detemine if one side is male an the other is female.


Tim

Tim, thank you for taking the time to explain this to me. This is all new to me and I am still learning. The photos were taken last October when the bird was three months old. This was before before it had molted to its adult plumage and matured sexually. I think your theory that it is a gynandromorph with a functional ovary is correct since its comb reddened up when it was just 3-4 weeks old. It looked and acted more like a cockerel, with a large bright red comb, until about a month ago. there are no recorded examples of the changes that occur during the development from a young bird to an adult. These birds may go through a number of changes although few have functioning ovaries. It is only 4-1/2 months old.

Paul,

I did some research and I have found a paper that deals with sex determination in birds and mammals. The paper is co-authored by some of the scientists at Edinburgh. After the egg is fertilized in mammals, each cell that develops from the fertilized egg is sex neutral and can not be identiifed as male or female. In birds, after the egg is fertilized the cells that develop from the fertilized egg will have a male identity or a female identity. The male cells have a different molecular mechanism in them than the females. The mechanism determines if the cells are female or male. I need to sit down and analyze the paper and get a better grasp on the idea.


Tim

 

[pokey]

Quote:
I am no expert but it seems just differently colored.the wattles are even on both sides also indicating both sides are male.

 

[Redcatcher]

Quote:
I am no expert but it seems just differently colored.the wattles are even on both sides also indicating both sides are male.

It looks like a half sider or mosaic to me. All half siders are gynandromorphs to a degree. It depends on how early in incubation that the division began. If the embroyo was just a few cells, then the midline is drastic. Later on, the bird will look more like patchwork.

 

[Minniechickmama]

Okay, I found it, and it was YOUR thread!

So, I guess you already know the 'g' word.

Good luck with her/him/it.

 

[Redcatcher]

Well, we are not 100% certain what we are looking at now. I took this photo of it last night. It molted and new feathers are just starting to come in now. There are what appears to be male hackle feathers coming in. They are dense, hard and glossy like a male. You can see how heavy the hackle feathers are now and half of them are just pin feathers. There may be saddle and sickle feathers too. Just too early to tell. The other side is sort of a partridge columbian mix. At any rate, the hackle feathers do not appear to be 100% female to me.

 

[dutchhollow]

OK, have a question, this relates to ringneck pheasants, not chickens. We raise about 10 thousand a year, each year we get around 10 what I call hemraphrodites (sp?), Look like a cross between male and female, some with female body coloring and rooster tails and heads, some with rooster body's and hen tails, some cackle like a rooster and some act like hens. Have never opened any up to see what is going on inside. But, I have never seen any split in 'half' as these are (one side to other?). Are we talking two different things here?

 

[Redcatcher]

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They are likely chimeras or mosaics as the odds of hatching a chimeric chicken is 10,000 to 1 so that would be about the right ratio if the same is true for pheasants. There are many different types of chimeras. Some are split right down the middle, some are not. A lot depends on how far along into incubation, the defect occurred and how. The germline is already established by the 8th day so half siders have to have occurred very early on. Sexual chimeras or gynandromorphs normally have both male and female sex organs but they are only partially developed. No two seem to be exactly alike.

 

[dutchhollow]

I will have to go take some pictures of this years, I do believe we have one from a few years ago mounted, and I know which pen there is one in now (we have about 2 acres under nets, so it might be tough to find them)

 

[Mahonri]

Now I'm wishing I would have kept that EE.

Oh, well.

For the original bird in question. to me it looks male on the dark side and female on the lighter side.

 

[Redcatcher]

Quote:
I think so too and would make sense. Since chickens normally have only one functioning ovary on the left, and the female side is on the left as well.

Can you get your EE back? It could help unlock some of the mysteries regarding these birds and ALL birds in general. Especially if you still have the parent birds. They are also interested in knowing the behavior. Only a handful of these birds have ever been documented. They do turn up on occasion but either they go unnoticed or are culled as being defective. Could yours have had more than one father? That is the theory so far is that they have more than one father. If yours had only one prospective father, it may answer some questions!