Is my dog getting enough calcium in his/her diet?
Commercial dog foods already contain all of the necessary components your dog needs. This makes it much easier to maintain a stable diet with proper nutrition. However, if you make your dogs food at home like we do, it can be a little trickier. It is important to follow a proper diet plan to ensure that all your dogs nutritional needs are met.
The recommended calcium intake for healthy adult dogs is 50 mg per kilogram of body weight. This means a 10 lb dog will require roughly 225 mg of calcium per day.
Age, breed, gender, and lifestyle also play a role in how much calcium a dog needs in their diet. If a dog has been pregnant and is nursing she will need more calcium than normal to maintain her strength and to promote healthy bone growth in her pups. Too little calcium while pregnant can be a problem as it can lead to a condition called eclampsia, which is potentially deadly.
Egg Shells As A Source Of Calcium
While many home made diets use egg shells as a source of calcium, they’re deficient in other minerals. The amount to feed is about 1 teaspoon per pound of food, which is about 5 grams. Here’s how calcium balances the minerals in foods for adult dogs. As you can see, egg shells can only be used with very lean meats. If you feed more than 10% fat (including any oils you add to the food), your dog will not get enough phosphorus.
| 1 teaspoon Eggshell Powder (5 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 2.35 | 1.19 | 2:1 |
| 15% Fat (85% Lean) | 1.91 | 0.89 | 2.2:1 |
| 20% Fat (80% Lean) | 1.61 | 0.69 | 2.4:1 |
| AAFCO Adult Minimum Requirements | 1.25 | 1.00 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Puppies need nearly double the amount of calcium as adult dogs. So if you double the amount of egg shells, there’s enough calcium in the diet. But because egg shells only contain calcium, it still won’t meet minimum AAFCO requirements for phosphorus. So eggshell powder is not recommended for growth and reproduction.
| 2 teaspoon Eggshell Powder (10 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 4.62 | 1.19 | 2:1 |
| AAFCO Puppy Minimum Requirements | 3.00 | 2.50 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Like egg shells, coral calcium is also extremely high in calcium but relatively low in phosphorus. This also makes coral calcium a poor choice for adult dogs eating a moderate to high fat diet. If you choose coral calcium as a calcium source, you need to make sure your dog’s meals are very lean or there can be a mineral imbalance and phosphorus deficiency. Feed 3/4 teaspoon per pound of food that’s no more than 10% fat. Any food that contains more than 10% fat will cause a phosphorus deficiency.
| 3/4 teaspoon Coral Calcium Powder (3.6 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 1.79 | 1.17 | 1.5:1 |
| 15% Fat (85% Lean) | 1.46 | 0.88 | 1.7:1 |
| 20% Fat (80% Lean) | 1.24 | 0.7 | 1.8:1 |
| AAFCO Adult Minimum Requirements | 1.25 | 1.00 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Puppies would need a larger amount of coral calcium to meeting AAFCO minimum requirements. But doubling the amount of coral calcium doesn’t raise phosphorus levels enough to properly balance the minerals. So coral calcium should not be fed to puppies and pregnant or nursing dams.
| 1 1/2 teaspoon Coral Calcium Powder (7.2 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 3.44 | 1.16 | 2.9:1 |
| AAFCO Growth & Reproduction Minimum Requirements | 3.00 | 2.50 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Seaweed calcium is another calcium source that’s high in calcium and low in phosphorus. This also makes it a bit tricky to use with anything but very lean meats. Like coral calcium, adding more seaweed calcium won’t help balance the minerals because there will still be too little phosphorus. Feed 1 teaspoon per pound of food that’s no more than 10% fat.
| 1 teaspoon Seaweed Calcium Powder (3 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 1.50 | 1.22 | 1.2:1 |
| 15% Fat (85% Lean) | 1.22 | 0.91 | 1.3:1 |
| 20% Fat (80% Lean) | 1.03 | 0.71 | 1.5:1 |
| AAFCO Adult Minimum Requirements | 1.25 | 1.00 | 1:1 |
| AAFCO Puppy Minimum Requirements | 3.00 | 2.50 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
You would have to add 3 teaspoons of seaweed calcium to meet the minimum calcium requirements for growth and reproduction. But this doesn’t provide enough phosphorus and the Ca:Ph ratio doesn’t meet AAFCO requirements. So seaweed calcium is not recommended for growth and reproduction.
| 3 teaspoon Seaweed Calcium Powder (9 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 4.34 | 1.29 | 3.4:1 |
| AAFCO Puppy Minimum Requirements | 3.00 | 2.50 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Bone meal is bone that’s been dried, either with or without heat. Minerals are pretty resistant to heat, so it’s generally safe to heat and powder bones. But you can also find higher quality sources of bone meal that hasn’t been heat treated, which would be preferred.
The benefit of bone meal over other sources of calcium is that there’s much less risk of mineral imbalance. Bone meal will almost always give you the proper ratio of calcium and phosphorus, just as real bones will. Feed about 2 teaspoons per pound of food to adult dogs.
| 2 teaspoons Bone Meal Powder (8 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) | 2.12 | 2.15 | 1:1 |
| 15% Fat (85% Lean) | 1.72 | 1.67 | 1:1 |
| 20% Fat (80% Lean) | 1.46 | 1.34 | 1.1:1 |
| AAFCO Adult Minimum Requirements | 1.25 | 1.00 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
Calcium For Puppies & Pregnant/Nursing Dogs
Apart from fresh bones, bone meal is the only source of calcium that should be fed to puppies and pregnant dogs. Because it contains both calcium and phosphorus in the right ratio, larger amounts will deliver enough calcium without creating the imbalance between calcium and phosphorus seen with the other calcium sources. The amount to feed is about 4 teaspoons per pound of food for meals that are 10% fat. If feeding 15% fat, then there won’t be quite enough phosphorus, so feed 5 teaspoons. If there is 20% fat or more (more than 20% fat is not recommended for puppies), then increase the amount to 6 teaspoons.
| 4 teaspoons Bone Meal Powder (16 g) Added To 1 Pound Food: | Calcium | Phosphorus | Ca:P |
| 10% Fat (90% Lean) – Add 16 g Bone Meal or 4 tsp | 4.09 | 3.09 | 1.3:1 |
| 15% Fat (85% Lean) – Add 20 g Bone Meal or 5 tsp | 4.12 | 2.81 | 1.5:1 |
| 20% Fat (80% Lean) – Add 24 g Bone Meal or 6 tsp | 4.13 | 2.62 | 1.6:1 |
| AAFCO Puppy Minimum Requirements | 3.00 | 2.50 | 1:1 |
| AAFCO Maximum Requirements | 6.25 | 4.00 | 2:1 |
How Much Calcium Do Dogs And Puppies Need?
If you want to get calcium right, you also need to get phosphorus right. Both minerals are tightly regulated in the body by the parathyroid hormone and vitamin D. Calcium needs to first be combined with phosphorus before it’s stored in bones … so just as too little calcium can cause skeletal issues in dogs, so can too little phosphorus. Calcium and phosphorus combine to give bones their structure and strength.
If there’s too much phosphorus in the diet, calcium will be pulled from the bones to balance out the blood levels of phosphorus. So too much phosphorus in the diet will also weaken bones and cause calcium deposits in soft tissue. So when you’re adding calcium to homemade diets, you have to pay attention to both calcium and phosphorus. Here are three things you need to consider:
AAFCO Calcium Requirements
AAFCO has set minimum and maximum requirements for the amount of both calcium and phosphorus in dog foods. We can also use AAFCO requirements to make sure our homemade diets have the right balance of calcium and phosphorus. Because puppies need larger amounts of calcium, there are different requirements for dogs and puppies:
| Min Calcium | Max Calcium | Min Phosphorus | Max Phosphorus | Min Ca:P | Max Ca:P |
| 1.25 g / 1,000 kcal | 6.25 g / 1,000kcal | 1 g / 1,000kcal | 4 g / 1,000kcal | 1:1 | 2:1 |
| Min Calcium | Max Calcium | Min Phosphorus | Max Phosphorus | Min Ca:P | Max Ca:P |
| 3 g / 1,000 kcal | 6.25 g / 1,000kcal | 2.5 g / 1,000kcal | 4 g / 1,000kcal | 1:1 | 2:1 |
Meat is very rich in phosphorus and contains very little calcium. On the other hand, bones are rich in both calcium and phosphorus with a Ca:P ratio that averages about 2:1. So an all-meat diet will be deficient in calcium and you need to add calcium in some form.
A lot of raw feeders add bone to their meals to balance the Ca:Ph ratio … but many raw fed dogs can’t eat bone. Senior dogs, dogs with poor teeth, small dogs and puppies can find it difficult to consume bone, putting them at risk for calcium deficiency. Plus, bones can splinter or break teeth. So many raw feeders add a different source of calcium to their foods.
Cooked foods can’t contain bones because bones must be fed raw. So cooked diets always need a source of calcium. So let’s take a look at calcium sources you can add to raw and cooked meals.
There are several sources of calcium you can add to your dog’s food … but they’re not all the same and they’re not all suitable for puppies. The most common calcium supplements and foods you can add include:
Each calcium source has different amounts of minerals. Here’s the breakdown in dry matter:
| Calcium Source | Calcium | Phosphorus | Ca:P | Magnesium |
| Egg Shells | 33.7% | 0% | – | 0 |
| Coral Calcium | 34% | 0.1% | 425:1 | 2.4% |
| Seaweed Calcium | 34.2% | 0.8% | 41.7:1 | 3.42% |
| Bone Meal | 19.3% | 9.3% | 2.1:1 | 2.46% |
| Bone | 15.6% | 2.9% | 2:1 | 0.11% |
Of course, real bone is the gold standard when it comes to supplementing calcium. It has a Ca:Ph ratio of 2:1 so it contains a good amount of phosphorus and also contains magnesium and vitamin D. In comparison, seaweed and coral calcium contain very little phosphorus. And eggshells are drastically different from bone with no measurable amount of phosphorus or magnesium. This makes eggshells a fairly unnatural alternative to bone.
Let’s look at each source of calcium next and how much you need to add to your dog’s meals.
How To Make Natural Calcium For Your Dog | Gastro Pup | Healthy Pet Treat
As with most things related to dog nutrition, the recommended amount of calcium varies but expect to supplement with about one 600mg calcium supplement per 10 to 15 pounds of adult dog. If you’re mixing homemade and commercial food, only add supplement for the portion of homemade diet, not the total.