Egg Irregularities

Two Eggs of Different Sizes from Backyard Chickens
The extra large egg compared to an average size egg.

This week, we’ve had two egg irregularities show up. The first one was a larger than normal egg, and the second was a spotted egg. Both eggs came from our Ameraucanas, Suzy and Reba. Over the years, we have occasionally seen a spotted egg, but none of our girls ever laid them consistently so we have never been too concerned. However, the large egg was a surprise. I was so eager to crack it open and see what was inside, as though that would give me a clue as to why it was so big. No double yolk or anything though. It was just bigger. After both of these girls laid irregular eggs, I decided to do a little research. Since they are new layers, and these irregularities have only happened once, it turns out there’s nothing to worry about. But why did they happen?

Egg Size

Varying egg sizes in new layers can be the result of an immature shell gland. In other words, their bodies are still figuring this whole egg laying business out. If your hen is laying odd sized eggs after a year or more of laying, you will want to read more about this as it can be a sign of something more serious.

Spotted Eggs

Learning about the cause for a spotted egg was really interesting to me. As it turns out, I didn’t know much about the reproductive system of hens. Apparently, all shells start as white inside of the hen, and in the uterus, during the end of the shell formation stage, the pigment is added.

So, Chloe, who lays white eggs, has one less step than Suzy and Reba. Suzy and Reba first add blue pigment to their eggs and then a layer of brown to create their green eggshells.

What does this have to do with a spotted egg? Well, a spotted egg can mean that as the egg passed through the oviduct, a long tube with several parts of the hen’s reproductive system, it paused for a brief period in the uterus. Since the pigment is added to the shell in the uterus, a brief pause means more pigmentation was added resulting in spots. Crazy, I know!

Luckily, both girls are back to laying spot-free and regular sized eggs. As I mentioned in a previous post, they are always teaching us! I also learned a lot of this information from the fabulous Chicken Chick, whose article included several helpful diagrams and images.

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