Double Yolked egg with another entire egg inside...

[grnidone]

Here is the video. I've seen many a double yolked egg (even a triple), but never 2 yolks with an entire egg along with it.

https://www.facebook.com/video.php?v=10208361868942224

My questions are this:

1. What causes the double yolk? (with or without the whole egg inside..)

2. A story here

http://www.dailymail.co.uk/sciencet...n-cracking-open-giant-chicken-egg-INSIDE.html

says that the second egg is from a "counter-peristalsis contraction."

Is this harmful for the hen?

 

[chickens really]

Check out the Chicken Chick...Great info on strange eggs...

 

[aart]

Here is the video. I've seen many a double yolked egg (even a triple), but never 2 yolks with an entire egg along with it.

https://www.facebook.com/video.php?v=10208361868942224

My questions are this:

1. What causes the double yolk? (with or without the whole egg inside..)

2. A story here

http://www.dailymail.co.uk/sciencet...n-cracking-open-giant-chicken-egg-INSIDE.html

says that the second egg is from a "counter-peristalsis contraction."

Is this harmful for the hen?

I think that basically means the contractions that move the egg down the 'pipes' go into 'reverse' and the completed shelled egg moves back 'upstream' and it meets up with another yolk and the shelled egg gets encased wit the next yolk in another shelled egg. Not unheard of but not terribly common. It's more of a glitch and much more common with new layers while the reproductive system gets tuned up for the first time.

That's a rather clumsy explanation and pretty much the same as the article you linked...but hope it helps.