Chicken Lays Wrinkled Egg

Enclosed please find a picture of two eggs that were in the same nest the same day. They are both kind of deformed, flat on one side and wrinkled. I think they were from the same hen that day. I have never had an egg like this before and I have raised chickens for about 25 years. Maybe you can give some insight into what caused these eggs to be shaped like that. Five days have gone by now and I have not had any more like this.

Joe via e-mail

I agree that the hen laid both eggs on the same day. A thought I've heard is that, for some unknown reason, the hen retained one egg, then the next one came down against it, causing the two flat sides. This can't be quite right, since the first shell wouldn't have formed with a flat edge, so I think they probably formed simultaneously. I can't really explain why it wouldn't just form one large, double-yolked egg, however. Apparently, the membranes must form at different times, then the shell is laid down concurrently (maybe!).

We see these a little more frequently in turkeys. They are often called "slab-sided eggs." Rarely, a hen will lay eggs like this somewhat consistently, but usually it's just an occasional oddity.

Joe Kennedy found both wrinkled eggs in the same nest, and it is assumed by the same hen on the same day. Most of these unusual eggs will only happen once, usually when a pullet is getting started laying, or from and older hen whose laying has slowed down.

This Egg Harder to Explain

I was out collecting eggs this evening and opened my lay boxes and this egg was here. It is very soft and has a weird looking thing on the end of it. I have raised Rhode Island Reds for 20+ years and have never seen this before. I have oyster shell and grit in my coop free choice.

Can you tell me why this egg is like this and if I should single the hen out to treat her for anything?

Thanks a million for all your advice in every issue, that I read from front to back of course.

Charles, Ohio

This egg is not so easy to explain. Strangely shaped eggs such as this happen occasionally, and I don't really know what causes it. A virus that causes infectious bronchitis can cause misshapen eggs, but this is usually a more permanent thing and you'd see it more consistently.

Normally, an oviduct will produce an egg around a yolk as it passes through. If something else passes through, however, an egg will also be formed. If she lost a bit of tissue, for example, albumen, membranes, and shell will be produced around this tissue.

The most common time to see eggs such as this is when a hen is either just starting to lay or is going out of production. I don't think it is anything to worry about, and it definitely produced a conversation piece! I'd be surprised if you see this again.

It's amazing to see some of the interesting eggshells that occur, but sometimes it is very difficult to explain, and will likely not happen again.

Blindness in Chickens

I have a two-year-old black Silkie hen. I was treating her for leg mites with alcohol and she seemed to actually swallow some. This was over a month ago. Since then she has been very inactive and has been quarantined to another pen by herself. All she does is sit on her feeder and do nothing. She is not eating much either.

After closer inspection I saw she had smoky gray eyes. None of my other chickens are showing symptoms. I am beginning to think she is blind and am considering putting her down. Please help me decide what to do!

Sonya, West Virginia

I don't think she would have swallowed enough alcohol to have any lasting effect.

I suspect she is blind, however, as you said. Just as in humans, there are things which can cause blindness in chickens, and the gray, smoky eyes are usually a sign of blindness.

You don't necessarily have to put her down, however. We have had blind chickens here at the UW poultry research lab, and they got along quite well. (The researcher was studying a genetic trait that caused blindness in the chickens.) We usually kept at least one bird with sight in the same pen and the blind chickens seemed to be able to find feed and water that way.

You can usually tell if they are blind by waving a hand beside their eye. Most chickens, no matter how tame, will move their head away when you do this. Blind birds won't typically move away from this, since they can't see it.

One word of caution — blindness in a bird of that age is often caused by a disease called Lymphoid Leukosis. If your Silkie has this, she will likely have other symptoms as the disease progresses. This is a fairly common disease in chickens, and a lot of older chickens die from it.

As always, to get a firm diagnosis, you'd need to contact an avian veterinarian or your state veterinary diagnostic lab.