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Best Calcium Supplement For Chickens [Top Picks & Buyers Guide]

The importance of calcium for chickens is undeniable. It is, perhaps, the msot essential mineral that they must obtain.

And it plays a role for chickens of all ages.

Laying hens simply need sufficient calcium in the diet to produce strong shells for their eggs.

And for younger and growing birds need calcium for bone formation and growth.

The truth is, all chickens need this mineral.

It is in laying hens that calcium supplementation is often advised and recommended.

Chances are, that is why you are here.

You have a flock that includes some layers, and you’re looking to support their intake.

But what are the best options on the market?

I spent some time researching to find out. Comparing product quality with price with availability, here are the ones to consider:

Best Calcium Supplement For Chickens

Editors Choice
Small Pet Select Flaked Oyster Shell-Calcium Supplement for Chickens & Ducks (10lb)
Manna Pro Crushed Oyster Shell | Egg-Laying Chickens | 5 LB
Homestead Harvest Coastal Oyster Shell Calcium Supplement โ€“ for Chickens and Ducks (50 lb)
Product
Small Pet Select Oyster Shell for Chickens
Manna Pro Crushed Oyster Shell
Homestead Harvest Coastal Oyster Shell Calcium Supplement
Package Size
10 lbs
5 lbs
50 lbs
Editors Choice
Small Pet Select Flaked Oyster Shell-Calcium Supplement for Chickens & Ducks (10lb)
Product
Small Pet Select Oyster Shell for Chickens
Package Size
10 lbs
Manna Pro Crushed Oyster Shell | Egg-Laying Chickens | 5 LB
Product
Manna Pro Crushed Oyster Shell
Package Size
5 lbs
Homestead Harvest Coastal Oyster Shell Calcium Supplement โ€“ for Chickens and Ducks (50 lb)
Product
Homestead Harvest Coastal Oyster Shell Calcium Supplement
Package Size
50 lbs

Calcium Supplementation Details

Small Pet Select Oyster Shell for Chickens

Small Pet Select Flaked Oyster Shell-Calcium Supplement for Chickens & Ducks (10lb)
  • Oyster shell supplements calcium for laying hens
  • Increase strength of eggshells
  • Promotes healthy plumage of birds
  • 100% satisfaction guarantee**

What we like about this particular calcium supplement

  • Oyster shells are crushed finely and in a good size for chickens.
  • Works well in a chicken food dispenser.

What we do not like about this particular calcium supplement

  • Largest size bag is 10 lbs.

Manna Pro Crushed Oyster Shell

Sale
Manna Pro Crushed Oyster Shell | Egg-Laying Chickens | 5 LB
  • Pellet size crushed oyster shell
  • Great source of calcium
  • Builds strong eggshells
  • Heat-treated for purity
  • Provides calcium

What we like about this particular calcium supplement

  • Fresh shells with a great texture.

What we do not like about this particular calcium supplement

  • Shells are quite large and may need further grinding prior to serving.

Homestead Harvest Coastal Oyster Shell Calcium Supplement

Homestead Harvest Coastal Oyster Shell Calcium Supplement โ€“ for Chickens and Ducks (50 lb)
  • Perfect for free choice feeding
  • A balanced source of calcium
  • Builds strong eggshells
  • Made with oyster shells and crushed calcium carbonate
  • 50lbs โ€“ bulk pricing, Long shelf life

What we like about this particular calcium supplement

  • Most economical option and lasts a considerably long time.
  • Great value for money.

What we do not like about this particular calcium supplement

  • The bag is not resealable so makes it a challenge to preserve.
  • The larger bag makes it more challenging to store.

How Much Calcium Should I Give My Chickens?

Whether or not you should give calcium to your chickens depends on their age. For young chicks and chickens under 18 weeks, you should not be supplementing at all. For laying hens, then some supplementation may be required.

First and foremost, you do need to consider their feed.

Most formulated feeds will already provide enough calcium, along with a number of other trace minerals.

It is therefore essential that you only supplement calcium if your chosen laying feed does not provide much if any, calcium.

Or if your birds are fed grains, scraps, or free-range regularly.

In those instances, calcium supplementation may be required to ensure your birds are getting sufficient calcium through the diet.

A diet that contains more grains and scraps will naturally be lower in calcium and higher in phosphorous.

Nevertheless, an adult laying hen should intake between 4-5 grams of calcium per day.

Calcium Supplementation Options

There are generally two different ways of providing calcium supplementation to chickens; via crushed oyster shells or through providing crushed eggshells. 

Oyster shell calcium is perhaps the best, most versatile, and time-saving way to boost your flocks’ calcium intake.

Some chicken keepers decide to break down and crush their flock’s eggshells before feeding them back to their hens.

And while this works well, it can be messy and takes time and effort.

Thus, purchasing a pre-existing oyster shell supplement is a much more practical approach.

Can Chickens Eat Too Much Oyster Shell?

It is possible to provide too much oyster shell calcium to chickens. In fact, by doing so, your chickens are likely to experience some adverse side effects. 

And it’s easily done.

If you are providing your hens with a layer feed that contains 4% calcium, then if they eat the recommended 120-150 grams of feed per day – they’ll already be meeting their calcium needs.

So first and foremost, it depends on what and how much poultry feeds your chickens consume.

If your chickens free-range or receive scraps more regularly, then providing oyster shell calcium in a separate dish away from the feed is the recommended approach to take.

This way, your hens can help themselves when they need it – which will likely be in the late afternoon as they prepare their bodies for the shell of the following days’ egg.

Nevertheless, it is essential that you get the balance of calcium to phosphorous ratio right. It should be balanced – which means not providing too much calcium, or of course, too little.

In the short term, if you were to overfeed calcium, then it will naturally get excreted.

But if too much calcium were to be supplemented long term, then phosphorous deficiency can occur.

And side effects to look out for here include:

  • Reduced egg production,
  • Pimples on eggshells,
  • Eggs with rough textures due to calcium deposits,
  • Reduced feed consumption

Do Laying Hens Need Oyster Shells?

Laying hens may need oyster shells, but it depends primarily on their layer feed. If they are consuming a diet exclusively of layer feed, and it already contains calcium, then chances are they do not need additional oyster shell supplementation. 

That being said, there are situations where calcium supplementation may be required and beneficial.

Such as when your birds are otherwise healthy, and you begin to notice shell quality issues.

Thin shells, thin spots, and general malformations are classic signs of poor eggshell quality and usually indicate more calcium is required in the diet.

Finally

Ensuring your hens get enough calcium is essential for high-quality eggs with sufficiently strong eggshells.

While they may be getting a decent amount of calcium already from their layer feed, chances are if they free-range or are fed scraps in any capacity, some supplementation will be required.

And when it comes to the best calcium supplement on the market, it’s hard to look past a decent Oyster Shell.

And for that, the Small Pet Select option is reviewed somewhat favorably.

Take a look at those reviews on Amazon yourself, and you will soon see why! ????

Small Pet Select Flaked Oyster Shell-Calcium Supplement for Chickens & Ducks (10lb)
Small Pet Select Flaked Oyster Shell-Calcium Supplement for Chickens & Ducks (10lb)
Oyster shell supplements calcium for laying hens; Increase strength of eggshells; Promotes healthy plumage of birds