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How an Egg is Formed - Egg Anomalies - Abnormal Eggs - Egg-cellent Information

Chicken egs come in various sizes and colors.

Chicken egs come in various sizes and colors.


I grew up on a farm and all of our chickens laid the normal everyday white to brown eggs. Nothing fancy, just your normal ordinary eggs. Then I discover that chickens actually lay colored eggs, most lightly tinted greens and blues, but colored. That intrigued me.

Then the other day I ran across an egg anomaly that looked like it just couldn’t possibly be real. It had to be fake photography or something. It was called an egg inside an egg. As I researched further I discovered there are many egg anomalies that I had never heard of. But before we discuss these anomalies, it is good to understand the egg laying process.


egg-inside-an-egg

Egg Laying Process

It takes approximately 10 days for a yolk to mature within a follicle in the hen’s ovaries before it is then released into the infundibulum where it is fertilized by stored sperm.

From there it is funneled into the magnum where more than 40% of the egg white is formed, and into the isthmus where more egg white is produced and the shell membrane is created, then into the shell gland pouch where approximately 40% more (the balance of) egg white is added along with the egg’s shell.

In the vagina, the outer part of the egg’s shell is formed. The egg is passed from the body through the vent.


An Egg Takes Its Time

Ovulation usually takes place in the morning. The total time it takes for an egg to form is anywhere between 24-26 hours. The white of an egg takes about 3-1/2 hours to form. The shell membrane takes approximately another 1-1/2 hours. The process is finished when the shell has been formed.


Double Yolks +

I have seen some double yolked eggs, or double yolkers. These are generally produced by a young hen (pullet) who has recently started laying eggs and whose reproductive system has not yet gotten the timing of their yolk production correct, releasing two at once. If multiple yolks are present two is the norm; however an egg has had up to nine! In the video below they are cracking open a double and a triple yolker! Notice how big the eggs are compared to how big the others in the carton are.

No Shell

I remember getting a few of these when gathering eggs. These eggs felt a whole lot like a water balloon, just a little firmer; and the membrane feels tougher and more textured than the surface of a balloon. The membrane can be quite translucent.

As an egg is formed, after the membrane is secreted, a shell is supposed to be formed around this. If things don’t flow just right, the egg can slip through without producing a shell.


Egg Within an Egg

Double shelled eggs are so rare that no one knows why they happen. It is thought that they might be formed when an egg becomes reversed or stopped in the reproductive system and joins with another egg that is also passing through. This video shows someone discovering an egg inside an egg. (They knew something was up because of the size of the egg.)

Odd-Shaped Eggs

Odd shaped eggs like those seen to the right are an accident.


The egg in the top picture did not rotate properly in the oviduct and much of the shell material was deposited in one location.


The egg pictured in the bottom picture is over 2-1/4” (5.7 cm) long and less than 1-1/4”(3.2 cm) diameter in the middle.


A spoon-shaped egg was found in China that was 3.3” (8.5 cm) long and varied in diameter from 1/2"-3/4" (1.3-1.9 cm)! Another egg found in China had what appeared to be a tail.

No Yolk

Eggs with no yolks (no-yolkers) are also called “dwarf eggs”, “cock eggs”, “wind eggs” or more commonly “fart eggs”. This type of egg is usually the result of a hen’s first attempt at laying eggs. Because these eggs lack the yolk, they are smaller than your typical egg.

The term "cock egg" is interesting because when the term was developed people really thought they were laid by roosters and that was why they had no yolk (Yolk indicates fertility).


This wraps up our egg hunt. Do you have an unusual egg you would like to feature in this article?



Humorous Poultry Stories:

Recipe Using Eggs:

Comments: "How an Egg is Formed - Egg Anomalies - Abnormal Eggs - Egg-cellent Information"

Cindy Murdoch (author) from Texas on May 03, 2013:

I grew up on a farm, and have seen most of the anomalies myself, but I also have never seen a double shelled egg. It would be interesting to run across and this anomaly could be undetectable and slip thru the inspectors. Thanks so much, astonerattnet!

astonerattnet from South Central PA on May 03, 2013:

I've had the 'no shell' and of course the 'double yolkers' but can't say I've ever seen the double shell.

Imagine most of these anomolies are filtered out of the commercial food chain so people that get their eggs from the store wont ever see most of these. It's a shame how disconnected from their food people are today.

Cindy Murdoch (author) from Texas on May 28, 2012:

Marcy - I remember some of the eggs that had the membranous shell from my days on the farm. And then also, I remember those that are misshapen with ridges. I don't remember any with two yolks or no yolks, and the egg in an egg is even stranger. But it is these oddities that keep life interesting! Thanks so much!

Marcy Goodfleisch from Planet Earth on May 26, 2012:

When I was growing up, we used to see double-yolked eggs even in the ones delivered to the house. Not very often, but enough that I remember it. Once in a while, the chickens at my grandparents' place would produced two yolks in an egg, but rarely. I haven't seen one in years. I'd never heard of the eggs without yolks or the ones with no shell.

As always with your hubs, this is excellently researched and written - great work! Voted up and shared on Pinterest!

Cindy Murdoch (author) from Texas on October 02, 2011:

Movie Master - you do seem to come by after here, but I'm just glad you stop by. I think she is here late at night after I have published and then you follow the next morning. Thanks for stopping by and for the votes!

Cindy Murdoch (author) from Texas on October 02, 2011:

They rarely lay non-shelled eggs, but they are kind of creepy. Hope you are able to get your chickens. It's satisfying to produce your own food - more work but satisfying. Glad you found the article useful.

Movie Master from United Kingdom on October 02, 2011:

Hi homesteadbound, it seems I am always trailing behind cloverleaf!!

Very interesting and I've learnt loads! eggs without a shell, eggs with 9 yolks!

Many thanks for sharing and voting up.

LABrashear from My Perfect Place, USA on October 01, 2011:

Lots of great information! We're actually thinking of getting a few layer hens. I think I'll make my husband gather the eggs - in case of any creepy non-shelled eggs. :) Thanks for sharing. Going to bookmark and voting up!

Cindy Murdoch (author) from Texas on October 01, 2011:

Cloverleaf- It's hard to imagine how a chicken could survive after laying one large enough to have that many yolks. Thanks for the votes.

Cloverleaf from Calgary, AB, Canada on October 01, 2011:

Hi homesteadbound. I had no idea that double yolks were even possible. I couldn't even imagine nine yolks! Great stuff, voting up and really interesting :-)

Cindy Murdoch (author) from Texas on October 01, 2011:

billabongbob - Thanks so much for stopping by and for the votes.

billabongbob from South Wales, UK on October 01, 2011:

Excellent hub homesteadbound, I've learned a lot about eggs. Voted up in every way ;).

Cindy Murdoch (author) from Texas on October 01, 2011:

truthfornow - so glad to share the unusual Mr. Egg with you.

Marie Hurt from New Orleans, LA on September 30, 2011:

I learned stuff I didn't know about eggs. Very well-researched article. Thanks.

Cindy Murdoch (author) from Texas on September 30, 2011:

AliciaC - I'm glad you enjoyed it. It sure would be interesting to see that spoon-shaped egg in real life, wouldn't it? Thanks for coming by!

Linda Crampton from British Columbia, Canada on September 30, 2011:

Your hub contains very interesting information and great videos, homesteadbound! I enjoyed learning about unusual eggs.

Cindy Murdoch (author) from Texas on September 30, 2011:

thelyricwriter - they sure does have an amazing journey to make. It's pretty amazing to think it takes a whole day just to lay one egg. Thanks for stopping by!

Richard Ricky Hale from West Virginia on September 30, 2011:

Great hub. I never knew the egg had to take that path. It is truly amazing of all the different sizes of eggs. Bery informative. Thanks for sharing your knowledge. Best wishes.