What is oyster shell?
The most popular and reliable medium for making sure your hens get enough calcium in their diet is oyster shell grit. Oyster shell grit is used to provide birds with enough calcium to produce strong bones and good egg shells.
•Don't confuse oyster shell with grit. Grit is insoluble. It stays in the gizzard and it's used to grind food. Oyster shell dissolves in the gut. Its job is not to do with digestion - it's to add calcium to the diet of laying hens.
•Some people use the egg shells from their own hens instead of buying a commercial product. However, if a hen already suffers from lack of calcium there's unlikely to be enough in her own shells to supplement her needs.
•It's fine to mix in some egg shells with oyster shell supplement but if you decide to do this, it's wise to bake the shells first in order to kill any bacteria, and to crush it small before offering.
•However, commercially produced oyster shell is relatively inexpensive, lasts for a long time and is very effective. For that reason I recommend using that rather than your own eggshells. We use it on our hens and always have strong, healthy eggs.
•Good for all avian species as a natural organic source of dissolvable calcium.
Why do laying hens need oyster shell?
•Making egg shells takes a lot of calcium, and some laying hens create one egg each day. That's a lot of calcium.
•If a hen doesn't have enough in her diet, her body will steal calcium from her bones to create the egg shell. That leaves bones very brittle with the potential for easy breakages - like osteoporosis in humans.
•Lack of calcium in the diet can also lead to soft-shelled eggs, which in turn can lead to egg-binding, a potentially fatal condition.
•Although some commercial feeds contain calcium, it is not enough to supplement the amount a laying hen uses. She therefore needs to be offered additional calcium in her diet - and oyster shell is an excellent source.