I don't know if this helps at all (for a 60lb dog, but maybe you can work it out):
How much bone meal powder to add to ground raw?
Make sure you're adding organ meat, heart is muscle meat (you probably already know that, but I'm just saying it anyway)
I also found this:
DogAware.com Articles: Homemade Cooked Diets for Dogs
One of the most common mistakes that people make when feeding a home cooked diet is the failure to add calcium. You must add calcium when you feed a diet that does not include bones.
Adult dogs need around 800 to 1,000 mg of calcium per pound of food fed. They also require the calcium to be supplied in a proper proportion to phosphorus.
The ideal calcium
hosphorus ratio in the canine diet is between 1:1 and 2:1. Meat contains a lot of phosphorus, so the more meat a diet contains, the more calcium will be required to reach the correct calcium
hosphorus ratio. Adding 800 to 1,000 mg of calcium will provide the correct calcium
hosphorus ratio even for a high-meat diet, unless you use a calcium supplement that also contains phosphorus. In that case, moderately higher amounts of calcium may be needed to balance out the additional phosphorus contained in the supplement.
Ground eggshell can be used as a calcium supplement. Rinse eggshells and dry them on a counter overnight, or in the oven, then grind them in a clean coffee grinder. One large eggshell provides one teaspoon of ground eggshell, which contains 2,000 mg of calcium, so add ˝ teaspoon ground eggshell per pound of food fed. Don’t use eggshells that haven’t been ground to powder, as they may not be absorbed as well.
You can use other types of calcium supplements (any form of calcium is fine). Calcium from seaweed, such as http://www.amazon.com/gp/search?ie=UTF8&keywords=animal%20essentials%20calcium&tag=dogawacom-20&index=garden&linkCode=ur2&camp=1789&creative=9325, also supplies other minerals (including magnesium, iodine, and selenium) that are beneficial.
Bone meal is frequently used as a source of calcium in diets that don't include raw bone. However, bone meal contains calcium and
phosphorus. Different brands of bone meal supplements contain different amounts of calcium and phosphorus, but the calcium
hosphorus ratio is always the same: 2:1. To balance a diet that contains lots of phosphorus, then, you will need to give an amount of bone meal that will provide 1,000 to 1,200 mg calcium per pound of food to keep the ideal calcium: phosphorus ratio in the diet correct.
Look for bone meal supplements that are guaranteed to be free of lead and other contaminants. You can also use a purified bone extract called Microcrystalline Hydroxyapatite (MCHA), but most of these supplements also contain vitamin D in high amounts, which would not
be appropriate to use (see Supplements
section further on in the text).
Another option is to use a supplement designed specifically to balance a limited diet, including supplying the proper amount of calcium. There are two products designed to balance diets that are high in meat: See Spot Live Longer™ Homemade Dinner Mixes
and http://www.amazon.com/gp/search?ie=UTF8&keywords=wysong call of the wild&tag=dogawacom-20&index=garden&linkCode=ur2&camp=1789&creative=9325. Two additional products are designed to balance diets that are high in carbohydrates: http://cookforyourdog.com/ made by Furoshnikov's Formulas, and https://secure.balanceit.com/. Update: Balance IT now offers a https://secure.balanceit.com/marketplace2.2/details.php?i=23&cc= for high-meat, no-carb diets as well. See http://dogaware.com/diet/dogfoodmixes.html#vitaminmix
for up-to-date information on these and other supplements designed to balance homemade diets.
One last option is to use a dog food pre-mix to which you add meat, eggs, dairy, and other healthy foods. These pre-mixes will include calcium and other nutrients to balance out the fresh foods that you add. (See “Have Dinner In
,” WDJ April 2007 for more information on pre-mixes. Also see Dog Food Mixes
for up-to-date information on these and other supplements designed to balance homemade diets.)
If you feed meat with ground bone, there is no need to add calcium. (See “A Raw Deal
,” May 2007, for more information about diets containing ground bone.)
When you use supplements or pre-mixes designed to balance a limited diet, you should restrict the amount of liver you feed to no more than half the amount recommended below, due to high levels of vitamin A. Also, do not add kelp (due to the risk of excess iodine, which can interfere with thyroid function), unless the pre-mix instructs you to do so.
Remember that you should never feed cooked whole bones, unless they have been cooked into mush in a pressure cooker or by boiling for many hours. (This will only work with some chicken bones; other bones remain too hard no matter how long you cook them, though you can add some vinegar to the water to help leach out some of the calcium into the food.)
You can cook meat-based foods that contain ground bone, but this is not ideal. Cooking food that contains a large amount of ground bone can lead to constipation or even impaction. That’s why cooking ground-up necks, backs, wings, etc. -- or commercial blends that contain ground bone -- is inadvisable. Either feed this ground food raw, or add in an equal amount of meat (without bone) to lower the percentage of bone in the mix.
Again, when bones are fed, you do not need to add calcium to the diet.