6 Best Chicken Oyster Shell Supplements For Strong Eggs Old Farmers Swear By
Prevent thin, brittle shells with the right calcium. We review 6 top-rated oyster shell supplements trusted by veteran farmers for stronger, healthier eggs.
You pick up an egg from the nesting box and your thumb pushes right through the shell. It’s a frustrating, messy moment every chicken keeper experiences. This isn’t just an inconvenience; it’s a clear signal from your hens that something is missing from their diet.
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Why Oyster Shell is Key for Strong Eggshells
Calcium is the backbone of a good eggshell. A hen mobilizes a huge amount of it—roughly 20 times the calcium stored in her own skeleton—over the course of a year to produce eggs. While quality layer feed contains calcium, it’s digested and absorbed relatively quickly during the day.
The real magic of oyster shell is its size and composition. The coarse flakes of calcium carbonate sit in the hen’s gizzard and dissolve slowly over many hours. This provides a steady, timed-release supply of calcium overnight, which is precisely when the hen is doing the heavy work of forming the shell.
Without this supplemental, slow-release source, a hen will pull calcium directly from her bones to form shells. This leads not only to thin, weak eggs but can also cause serious long-term health issues, including osteoporosis and egg binding. Offering oyster shell isn’t just about getting better eggs; it’s fundamental to the health and longevity of your laying flock.
Manna Pro Oyster Shell: The All-Around Choice
If you walk into almost any feed store in the country, you’ll find a bag of Manna Pro oyster shell. It’s the dependable, no-frills standard for a reason. It gets the job done without you having to overthink it.
The consistency is generally a mix of small flakes and larger pieces, which works well for a mixed flock of standard-sized breeds. Hens can pick out the size they prefer. Because it’s so widely available, it’s also one of the most affordable options on the market, making it a practical choice for backyard keepers and small homesteaders alike.
This is the product you start with. There’s rarely a good reason to look elsewhere unless you have a specific need, like a flock of picky bantams or a commitment to using exclusively organic inputs. For 90% of flocks, Manna Pro is the right answer.
Scratch and Peck Cluckin’ Good Oyster Shell
For the farmer who prioritizes organic and non-GMO inputs, Scratch and Peck is the go-to brand. Their oyster shell is sourced and processed to meet the same standards as their popular feeds. This gives you peace of mind that you’re maintaining a consistent philosophy across your entire feeding program.
The texture of their shell is often a bit finer and more uniform than standard brands. Some keepers find their birds, especially smaller breeds or picky eaters, take to this consistency more readily. It mixes well with grit if you choose to offer them together, though keeping them separate is still the best practice.
The main tradeoff here is cost. Organic-certified products almost always come with a higher price tag. You have to decide if that premium is worth it for a simple mineral supplement. For many, it absolutely is.
Purina Oyster Shell: A Trusted Farm Staple
Ensure strong eggshells and healthy hens with Pecking Order Oyster Shell. This natural calcium supplement supports consistent egg production and promotes overall bone health in your flock.
Alongside Manna Pro, Purina is another legacy name you can trust. Generations of farmers have relied on their products, and their oyster shell is a straightforward, high-quality supplement. You know exactly what you’re getting every time you buy a bag.
Purina’s product is known for its clean, consistent sizing. You won’t find a lot of dust or overly large, unusable chunks. It’s a workhorse product designed for performance and predictability, reflecting the brand’s deep roots in production agriculture.
There isn’t a huge difference between Purina and Manna Pro for the average flock. The decision often comes down to brand loyalty or what your local co-op happens to stock. If you feed your flock Purina feed, it makes sense to stick with the brand you already trust.
Small Pet Select Shell for Picky Layers
Sometimes, you do everything right and your hens still turn their beaks up at the oyster shell. They might scratch it out of the dish or ignore it completely. For these frustrating situations, a product like Small Pet Select can be a problem-solver.
This brand often offers a different texture or flake size, sometimes a finer, more crushed consistency. This can be just different enough to entice a hen that has rejected the standard, chunkier flakes. It’s especially useful for bantam breeds, whose smaller beaks might struggle with larger pieces.
Think of this as your "plan B." If you notice your eggshells are still weak despite offering a standard oyster shell, and you see the supplement dish is always full, try a bag of this. It costs a bit more, but it’s cheaper than dealing with broken eggs and an unhealthy hen.
New Country Organics Shell: Sustainably Sourced
For some hobby farmers, where a product comes from is just as important as what it does. New Country Organics puts a heavy emphasis on sourcing and sustainability. Their oyster shell is often harvested from specific, clean coastal beds, appealing to keepers concerned about environmental contaminants.
This product is OMRI Listed for organic use, making it another excellent choice for the certified-organic homestead. The company’s commitment to regenerative practices resonates with farmers who view their flock as part of a larger ecosystem. You’re not just buying calcium; you’re supporting a particular agricultural philosophy.
Like other specialized organic options, expect to pay more. This is a values-based decision. If sustainable sourcing is a cornerstone of your farm’s mission, New Country Organics provides a product that aligns with that goal.
Mount St. Helens Grit Co. Shell in a Jug
Practicality matters on a small farm. The oyster shell from Mount St. Helens Grit Co. often comes in a sturdy, resealable plastic jug. This is a surprisingly useful feature, as it keeps the shell perfectly dry and contained, preventing spills and moisture clumping in a damp feed room.
Sourced from the Pacific Northwest, this product also has a unique origin story. While chemically it’s still calcium carbonate, some farmers believe that trace mineral variations from unique geographic sources can offer subtle benefits. The main draw, however, is the convenience and durability of the packaging.
This is a great option for someone with limited, less-than-ideal storage space or for keepers who only have a few birds and will take a long time to go through a big paper bag. The jug can be refilled and reused for years, reducing waste.
How to Offer Oyster Shell to Your Flock
How you provide oyster shell is just as important as which brand you choose. The cardinal rule is to always offer it free-choice in a separate container. Never mix it directly into your flock’s main feed ration.
Hens are brilliant at regulating their own calcium intake. A hen in peak lay will visit the oyster shell dish frequently, while a molting hen, a young pullet, or a rooster will ignore it. Mixing it into the feed forces every bird to consume it, which can lead to calcium overdose in non-layers, potentially causing kidney damage.
A simple, dedicated feeder is all you need. This can be a small ceramic dish, a hanging poultry feeder, or a purpose-built grit station. Place it somewhere the birds can easily access it, but where it will stay clean and dry. Check it weekly and top it off as needed—your hens will take care of the rest.
Ultimately, the best oyster shell is the one your hens will actually eat. Start with a reliable staple like Manna Pro or Purina, but don’t be afraid to try a different texture if your eggshells aren’t improving. Pay attention to your birds, provide what they need, and they’ll reward you with beautiful, strong-shelled eggs day after day.
