How to Safely Feed Your Chickens Crushed Eggshells
Author: Esther Donohue
Chickens need a lot of calcium in their diet, and extra calcium helps them build strong eggshells. If your chickens are laying thin-shelled eggs or brittle eggshells, they likely need a calcium supplement. There are a few ways to provide enough calcium, including feeding your backyard chickens crushed eggshells or commercial oyster shells.
I’ll walk you through how to prepare your eggshells safely so they can be used as a calcium supplement for your laying hens alongside their regular feed.
If you forget to buy a bag of oyster shells at the feed store, which I do all the time….—your own eggshells make an excellent calcium source for your flock.
Why Feed Eggshells to Chickens?
The main reason we feed crushed eggshells to our flock is simple: they’re an excellent source of calcium that’s readily available.
Plus, we love to reuse and recycle around the homestead. Rather than throwing away your own eggshells, why not repurpose them to improve eggshell quality in your laying hens?
Chickens need calcium carbonate to prevent health issues, maintain good hen health, and support egg production.
Without a good supply of calcium, hens may suffer from soft-shelled eggs or shell-less eggs, which can be a sign of serious deficiencies or another health issue.
Signs That Your Chickens Need Calcium
Calcium isn’t just essential for egg production, but also for a chicken’s overall health. Without plenty of calcium, chickens can develop brittle bones or leg issues. Here are signs your own flock may need additional calcium:
- Thin shells or thin-shelled eggs that break easily
- Soft-shelled eggs that feel rubbery
- Shell-less eggs (a potential sign of a more severe deficiency or health issue)
- Eggshell deformities (weak spots, holes, or uneven texture)
- Egg eating due to lacking calcium & protein
- Leg issues (especially in young chickens)
If you notice these signs, it’s time to offer a slow-release source of calcium, such as commercial oyster shells, ground oyster shells, or your own eggshells.
The Benefits of Feeding Eggshells to Chickens
- Natural calcium source to strengthen eggshell quality
- High calcium content, providing pounds of calcium over time
- Cost-effective compared to store-bought supplements
- Environmentally friendly—reduce waste by reusing your own eggshells
- Less reliance on commercial oyster shells and commercial feeds
Concerns About Egg Eating When Feeding Eggshells
A common myth is that feeding crushed eggshells will make your hens eat their own eggs. In my years of raising chickens, I’ve never had a problem with this.
Feeding your laying hens added calcium, table scraps, and good quality layer feed prevents them from seeking out other sources—like their own eggshells.
Now, if an egg cracks open, chickens will eat it, but that’s just because they love high-protein foods. However, if you already have a hen eating eggs, that’s a serious issue that needs to be addressed immediately.
How to Safely Prepare Eggshells for Chickens
Preparing crushed eggshells for your own flock is easy. There are a few methods, and you can choose what works best for you. If your looking for other ways to use eggshells, I love using them in my garden.
Baking Method (Best for Long-Term Storage)
- Spread your eggshells on a cookie sheet.
- Bake at 250°F for about 25 minutes to kill harmful bacteria & dry them out.
- Let them cool and crush them with a rolling pin, food processor or potato masher.
- Store in an airtight container for up to a year.
Air-Dry Method
- Spread your eggshells on a cookie sheet lined with paper towels.
- Let them air-dry in a well-ventilated area.
- Once dry, crush them into smaller particles using a rolling pin or potato masher.
I personally love using the potato masher—there’s something satisfying about crushing eggshells! My kids even join in, though I make sure we do it outside since eggshells tend to fly everywhere.
For storage, I use an air-tight container. Jars or even old mayo containers (the large ones) work great, just make sure the shells are completely dry or mold will grow in the container.
For feeding, I use an old rabbit feeder or a separate dish for free choice calcium supplementation. This way, my hens can take as much calcium as they need, without wasting any.
Eggshells vs. Oyster Shells as Calcium Supplements
There’s a lot of debate among chicken keepers about whether crushed eggshells are as effective as oyster shells.
Here’s a breakdown:
| Feature | Eggshells | Oyster Shells |
|---|---|---|
| Calcium Content | Moderate (high calcium content) | High (slow-release source of calcium) |
| Particle Size | Smaller particles & Larger particles | Larger pieces for slow-release source of calcium |
| Availability | Always on hand | Requires purchase |
| Cost | Free | Can be pricey |
| Best for | Supplementing hen’s diet & Ensuring a steady supply of calcium. | Ensuring a consistent supply of calcium |
Both options work, if you’re supplementing only with your own eggshells or oyster shells, make sure your hens also get a good quality layer feed and have access to free choice grit.
Final thoughts on feeding eggshells
Feeding crushed eggshells to your own flock is an easy, cost-effective way to provide additional calcium for strong shells and better egg quality.
Whether you bake or air-dry them, just make sure they are fully dry before storage to prevent mold.
Your backyard chickens will love the extra calcium, and you’ll love knowing you’re making use of something that would otherwise go to waste. Plus, it’s one more step toward a self-sufficient homestead!
Thanks for reading,
Esther
