Can a chick really have more than one father??

[SpringChickens]

A chimera is an animal which is made up of two completely different genotypes. It typically occurs when two embryos fuse for whatever reason so, therefore, it would not be possible in birds. So your skin can be from one genotype and your liver is another.

I heard a story about a person who was having trouble registering their horse. They only owned one mare and she had her foal. When it came time to do DNA testing to verify parentage of the foal, the stallion came back correct but the DNA test said it couldn't possibly be the mare's baby. They finally figured out that she was a chimera and her hair follicles had different DNA than her oocytes (eggs) did. They're rare, but they're amazing when they do happen!

 

[SpringChickens]

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I would be interested in learning more about this. I'm working on my PhD in reproduction and any time two or more sperm fertilize a mammalian oocyte, the embryo fails to develop beyond a certain stage.

 

[Bunnylady]

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I heard of a stallion that is a chimera, and one of his cell lines happens to be female. The hairs they pulled for his DNA test came from an area of that other cell line, so his results kept coming back "mare." I forget where they had to go on him to get the right results.

 

[VelvetDragon]

I agree: a chick (generally) can not have more than one father. It is possible that a clutch can have multiple fathers, with each chick having one father. What you're getting, likely, is a result of the genetics of the birds, rather than a mix of input from the dads.

Can a chicken EVER have multiple fathers? AMAZINGLY, yes. It's extremely rare -- 1 in 10,000 chickens. They are very distinctive -- they look like they're male on one side and female on another, and they're called gynandromorphs. This is not what is happening with your chicks, and it would certainly not happen multiple times in your clutches, or result in calicos. Here's an article with pictures!

A chimera (in genetics) is an animal that has groups of cells within their body that have different, distinct genetic signatures, from different zygotes (fertilized eggs forming cells) coming together and fusing into one animal. That is, two ova fertilized by two different sperm. They may have liver from one parental pairing, and a kidney from another, for example. It happens in nature and is also done on purpose in the lab.

One of the forms of chimerism that are most familiar to people are male tortoiseshell cats. Other sex-linked traits occurring in the "wrong" sex is sometimes a sign that the animal is a chimera. Again, it is rare; unlikely to happen to a person once, let alone multiple times at a single farm.

ETA: Whoops, several people posted while I was rebooting my computer, so I posted without seeing it. Yes, it's happened in horses. In fact, most (but not all) "brindle" horses are actually chimera (and therefore, despite EXTRAORDINARILY high stud fees, will not breed true).

Even more interestingly, this has happened in PEOPLE. Two women have had to fight to keep their children when DNA showed they were not the mothers. Extensive tests revealed the women to be chimeras.

 

[Stina]

One of the forms of chimerism that are most familiar to people are male tortoiseshell cats.

Male calico/tortoiseshell cats are usually a result of Keinfelter's syndrome...not chimerism. Kleinfelter's syndrome is males that are XXY instead of XY....it happens when the chromosomes do not separate normally during meiosis (sex cell production). Kleinfelter's occurs in many mammalian species and is the most common cause for sex linked traits showing up in male animals.​

 

[Cowgirl71]

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Here's a link to photos: https://www.backyardchickens.com/forum/viewtopic.php?id=295071&p=2 (scroll down)

I've hatched about 100 or so of these this year. The hens are VERY pretty!

 

[VelvetDragon]

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Male calico/tortoiseshell cats are usually a result of Keinfelter's syndrome...not chimerism. Kleinfelter's syndrome is males that are XXY instead of XY....it happens when the chromosomes do not separate normally during meiosis (sex cell production). Kleinfelter's occurs in many mammalian species and is the most common cause for sex linked traits showing up in male animals.

Actually, we're both wrong. XD Mosaicism is the main cause of male torties, rather than chimerism, I got that mixed up. Sorry.

They used to think the main cause was Kleinfelter's but since then they found that the most common cause was NOT Kleinfelter's. A study in 2000 showed Kleinfelter's accounted for 0.033% of chromosomally abnormal (XY/XY, XX/XY or XXY) tortoiseshell male cats in the US. Kleinfelter's cats often have other side effects of their disorder, including weight problems. Mosaicism on the other hand is a red cat with localised mutation of skin cells in the embryo (somatic mutation), which causes black coloring that isn't genetically inherited.

Here's an excellent page on the subject: Mosaicism, Torti Tomcats, and Genetically Impossible Kittens

 

[PunkinPeep]

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Here's a link to photos: https://www.backyardchickens.com/forum/viewtopic.php?id=295071&p=2 (scroll down)

I've hatched about 100 or so of these this year. The hens are VERY pretty!

Thanks for the link.

I had no idea that BO over BR would also make sexlinks.

Also, these calico didn't look anything like those. So i'm still confused, and i've already sold the chicks and didn't take good pictures while they were here. I could kick myself. I'm going to start a new hatch next week, so maybe my calicos will appear again, and i can show you a picture.

Thanks for all the crazy amazing info!

 

[americana-chick]

Is it possible that a double yolker could have 2 seperate fathers?

 

[ChooksChick]

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Yes, it is, just like fraternal twins, however those have their own sacs, where the 'sac' is inside the egg in birds.

There is a wonderful BBC production about chimerism in humans- I have some of the characteristics (line down middle of abdomen w/ two different distinct shades of skin tone) but they were inherited by both of my daughters, so we dismiss it. The program is wonderful to watch!! There's a case of a woman who had her 3rd child seized in the OR at delivery because the gov't thought she was committing welfare fraud when her DNA tests kept coming back that her children were birthed by her sibling, not her. There was also a woman who tried to donate a kidney to one of her kids or vice versa and the typing came back right, but the organ was a different blood type!

Biology is fabulous!!