A Listen Lissa reader writes in with a question about her hens’ funny-looking eggs:
I have a question about some funny-looking eggs. My chickens are a year old now, and have been laying for about seven months. Recently, I’ve noticed that two have had extra shell build-up on the outside of their eggs, sort of spotty. Should I be concerned?
Do your “funny-looking eggs” look something like this one?
The brown egg with the calcium deposits on the right side of this photo was laid by a Rhode Island Red hen
If they do, the short answer is this: there’s probably no reason to worry.
Younger hens and older hens sometimes have egg or shell irregularities that are really nothing to worry about. Funny-looking eggs sometimes happen. Young hens may take some time to get into the groove of laying, while older hens may have some issues when age means everything doesn’t run as smoothly.
That said, your hens are a year old, which is young, but really not so young that their systems haven’t worked out the kinks. They’re not old either. That means it would be a little more unusual for you to see funny-looking eggs from your flock regularly. (Occasional egg shell issues can occur because of stress, for example if a loud thunderstorm or a predator disturbed your hens.)
If it’s a regular occurrence though, take a look at their diet. We always recommend feeding a layer feed to hens (of course!), and offering oyster shell (as a calcium supplement) free choice. I’ve noticed that I see more calcium pimples on my eggs when I’ve replenished the oyster shell; my girls often seem to over-do it with the freshly-filled bowl! If you’ve just refilled your oyster shell, perhaps that’s what you’re seeing.
Another possibility is that some people choose to mix their oyster shell in with their feed. Is that something you do? If so, it isn’t the worst idea in the world, but it does mean your girls may accidentally get more calcium than they need. When they don’t need it, they will have to eat around it and actively avoid it. Excess can be excreted in the deposits and pimples on the shell. Remember, the oyster shell is meant to be a supplement, used by the girls just in case they need it. If you are mixing oyster shell into their feed, stop that for a while—offer it in a separate dish—and see if the problem doesn’t disappear.
It’s possible, too, to see more pimples or deposits when sunlight begins to wane and laying slows down. One of my girls has eggs with calcium pimples only between equinoxes (between September and March) because she lays fewer eggs then, but doesn’t change her diet significantly. In other words, she’s getting the same amount of calcium, but using it to produce fewer eggs.
You may see funny-looking eggs, too, if your hens have run out of water. As you can imagine, that’s bad for a number of reasons, but even being without water for a short time can temporarily stall an egg in your hens’ reproductive tract. If it gets stalled in the shell gland, extra calcium can be distributed on the shell.
Calcium metabolism in chickens is also affected by other nutrients like vitamin D and phosphorus. If you’re feeding a lot of treats—especially when you’re feeding oily treats like seeds—it’s possible for their nutrition can get a little out-of-whack. Cut down on treats to make sure they’re getting a proper nutritional balance. That may work. For instance, too much vitamin D can cause your hens to absorb too much calcium from their diet, which can then be deposited on egg shells, or even cause kidney or bone problems. This is why you should always offer treats in moderation.
Lastly, you may just have a hen whose shell gland doesn’t work perfectly. In other words, she may just be a hen who lays funny-looking eggs. That’s okay, too. Unless your girls showing other signs of illness (lethargy, a lack of appetite, changes in droppings, respiratory issues, etc.), it’s probably not a big deal. If you do notice something that makes you think they’re ill, contact a vet to get a firm diagnosis and treatment options.
If you have a question for Lissa, email info@mypetchicken.com, and use “Listen Lissa” in the subject line. Your email may be used in a future column.
Do our readers have any additional advice? Please share in the comments!