A cautionary note before you begin -- feeding a boneless diet day in and day out is not recommended because we simply do not have complete data on the nutritional composition of small cat prey.
That said, a boneless raw diet is far superior to commercial food (most of it containing very little if any real meat) which is cooked to within an inch of its life after which minerals including calcium, and vitamins are added to it.
Since different meats and veggies have varying amounts of calcium and phosphorus, it is imperative that you first determine how much calcium and phosphorous there is in a given type of meat so that you can then calculate how much calcium to add to a lb of meat to attain the ideal Ca:Phos ratio which ranges from 1.2 - 1.4 Ca: 1 Phos We have a calculator available to forum members that does this very easily.
At this web site, you can get the fat %, potassium, calcium, and phosphorous levels (plus a lot more) for most meats:
Above is where I got the numbers to perform the calculation for 1lb of turkey + organs for this recipe below (would have to recalculate calcium/bone meal, amounts if feeding beef, chicken, lamb, deer, turkey, rabbit, or any other meat):
(Note: this provides eight 2oz meals for a healthy 8lb cat with a "normal" activity level)
- 1 lb i,e, 453.56 grams raw ground turkey muscle meat (the darker the meat the higher its taurine content) - has 59mg Ca and 708mg Phos
- 1/2 piece i,e, 50grams of raw turkey liver - contains 2.5mg of Ca & 140mg of Phos; raw chicken liver can be substituted (its Ca & P are very close)
- 1 raw turkey heart i.e. 27grams - 2mg Ca and 60mg Phos (chicken heart #s for same weight are close)
- 3.5 oz or 100g chicken gizzards - contains 11mg Ca and 148mg Phos (turkey gizzards are hard to find)
- 2 tbsp steamed pureed veggies* - preferably high-moisture low-GI index squash, zucchini (all lightly steamed), or home-grown oat/barley/rye/wheat grass from seeds. For cats with CRF, pumpkin can be beneficial b/c it functions as a nitrogen-trapper. IBD cats too can be helped by the moderately fermentable fiber in cooked/canned pumpkin. For some reason, my cats love a steamed broccoli and cauliflower mix; do not use in raw form unless you have a cat with an overactive thyroid gland.
- 1 large raw chicken egg yolk and lightly cooked white of same egg i,e, 33g (being added to supply lutein, Vitamin D, iodine, fatty acids, lecithin and a host of other nutrients)
- 1478 mg calcium carbonate powder OR 3/4 teaspoon of eggshell powder** OR a bit less than 1.5 tsp of bone meal powder***
- 1/2 teaspoon unflavored Gelatin as a proxy for cartilage
- 1/2 teaspoon Dulse (has lower iodine levels than Kelp) to provide trace minerals and support thyroid function
- 2,000mg taurine
- 2-3 oz home-made meat broth or spring water to help with consistency
*Fiber: For cats allergic to veggies e.g. some IBD cats (FWIW, mine - Pigpen - is allergic to psyllium, but not to veggies or rice bran), substitute with rice bran or psyllium - 1/8 tsp mixed with 2 Tbsp water added each day to food, not to the whole mix. Pumpkin has a low GI-load though is moderate on the GI index, so if you have a diabetic cat, use either rice bran or psyllium or low-GI index veg e.g. fresh grasses, which are more likely to show up in a mouse's tummy than anything else. I have not found any blood glucose spike with using a small amount of grass vs rice bran vs psyllium, but YMMV so please check for yourself how your cat responds and feed accordingly.
**This calculation was done as follows:
Total mg of Caclium = 59 (ground meat) + 2.5 (liver) + 2 (heart) + 11 (gizzards) + 21.9 (egg yolk) + 2.3 (egg white) = 98.7mg in meat mix
Total mg of Phosphorous = 708 (ground meat) + 140 (liver) + 60 (heart) + 148 (gizzards) + 66.3 (egg yolk) + 4.9 (egg white) = 1127.2mg in meat mix
To get supplementation amount, multiply 1127.2mg (Phosphorous) times 1.3 = 1465.36mg Calcium - 98.7mg (total Calcium in the meat) = 1,366.66mg
If you add 1,366.66mg Calcium, your mix will have a final Ca:Phos ratio of 1,465.36/1,127.2 = 1.3:1
This comes to 1,366.66mg/2,000mg = 68.33% of a teaspoon of ESP. Since the accepted Ca:P for cats is in the 1.3 to 1.4:1 range, one can add up to 1127.2mg times 1.4 = 1,578mg Ca i.e. ~ 3/4 of a teaspoon of eggshell powder (ESP).
This is the bare minimum you would need to add. If you change the liver source or use a different meat source, you would need to make appropriate adjustments. If the phosphorous levels in that meat source are not higher than turkey or chicken muscle, liver, and gizzards, you can add close to the same amount of Ca or eggshell powder.
**Eggshell powder: 1 tsp of eggshell powder (ESP) contains somewhere between 4,500mg and 5,000mg total calcium (in carbonate form) depending on whether one goes by the US Egg Board or research by a vet at the Univ. of Florida (article used to be online, alas I did not make note of the reference).
A study published in Poultry Science (2000) referenced below, found that:
"ESP seems to have a beneficial composition with about 39% of elemental Ca, relevant amounts of Sr, and low levels of Al, Pb, Cd and Hg."
A colleague (fellow professor but unlike me, she's in Ag Science) and I ground up 3 large egg shells each in 3 different consistencies - medium, fine, and extra-fine, then weighed each of the resulting grinds in her lab. Our results ranged from 4,400mg to a shade under 5,080mg, so not hugely different, and enough to satisfy my curiosity. Deferring to the researchers in this field, I feel comfortable going with a range of 1,800-2,200mg of elemental Ca per teaspoon of eggshell powder.
Given the fact that teaspoon is a volume measure, and how finely ESP is ground determines just how much one can fit in a teaspoon, as long as one is not leaving the ground too coarse, somewhere in the 2,000mg elemental Calcium per teaspoon is a good ballpark.
I don't think it's safe to go too low with calcium, and since eggshell powder has been shown to not raise serum calcium levels, if you have to err, go a bit over rather than under in amount.
***Bone meal: If you want to get close(r) to feeding a whole animal/bird, i.e. as a substitute for real bones, bone meal might be a better choice because animal/bird bones contain a lot more than just calcium. Specifically they contain phosphorous & magnesium.
There's no getting around the fact that bone meal is a heavily processed product and one should be concerned about quality of bone meal to ensure BSE and contaminants including lead and arsenic are properly addressed by the manufacturer.
If you wish to use bone meal, there are some reputable brands such as NOW. It contains a 2:1 ratio of Ca:Phos, so each tsp. contains 1,000mg Ca and 500mg Phos (plus 25mg of Magnesium). so for each 1,000mg of Calcium, there is about 1/2 that amount being added back in Phosphorous. Clearly, using bone meal to "balance" (tricky word in this context) phosphorous levels in meat is not without its challenges.
if you wish to make your own ESP and/or bone meal, details at our recipe page here:
The following are drawn from AAFCO's daily adult maintenance requirements, and can be added into the mix at time of preparation. Meat contains most of the nutrients cats require, so these should be considered maximum amounts so as not to lead to overdosing problems.
Please adjust if you are planning to only include these at meal time (which is ideal, BTW) e.g. less B is needed if it will be added fresh at meal time because freezing causing loss of B vitamins. Also, if using Nordic Naturals liquid cod liver oil rather than soft gels, add at feeding time.
Vit E is the only item higher than AAFCO levels due to the addition of fish oil and to account for Vit E is lost in the freezing process. For what it's worth, AAFCO's recommendation would come to a total of only 7.5 IU per meal.
Total amounts based on 8 meals for 1 healthy adult cat at ideal weight:
- Vit A - 2,000 IU****
- Vit D - 200 IU
- Cod Liver oil in lieu of Vits A and D; matching up can be tricky because there is a different ratio of Vits A and D in brands e.g. for Nordic Naturals brand softgel has only 1 IU of Vit D per 300IU of Vit A. With Carlson's, 1 softgel would match Vit A but would have too much Vit D.
- Vit E - 2 400IU softgels of Carlson's d-alpha Gems OR GNC's Natural E 400 100% natural d-alpha dry capsules; these are the only two products forum members have been able to verify are soy-free (this caution includes similar products from even these brands).
- Vit B-complex - 1/8 capsule of Thorne B-Complex Formula #12 (least stinky cat-safe one on the market)
- Fish body oil e.g. wild salmon, sardine, anchovy, or krill oil preferably added at meal times: one 1,000mg softgel providing at least 300mg EPA & 200DHA - Nutricology, Carlson's or Nordic Naturals brand of fish oil,
one 250mg Jarrow krill oil
- Trace minerals -- of all the brands we've checked out on the list/forum, ConcenTrace Trace Mineral Drops seems to be the best option @ 10 drops per 1lb of meat. Note: chloride content is high, but then with other brands, there are other bigger/worse issues:(
****As per reference below (Harrson et al), in Table 4.1.29., if as a cat's daily food ration of 100g s/he eats a mouse, s/he'd get 6570 IU of Vitamin A; an adult rat would provide 3353 IU or approximately 50% of that amount with 6-week old chicken coming in at 355.9 IU. Hence the supplementation as chicken is rather low in Vitamin A compared to a mouse i.e. containing 9.4% of a mous'e Vit A amount or even a rat at about 18.5%. We do not have any information like this for turkey, but in other ways it is quite similar to chicken, nutritionally speaking.
Additional supplements for cats with IBD and other digestive issues best added at meal time, not into the whole mix:
- Digestive enzymes
There are other optional additions that can be made such as:
- egg yolk lecithin (during shedding/hairball season) e.g. Nature's Plus brand -- there was a study at UT Austin suggesting its use for hairball control. This is only if actual yolks or egg yolk powder are not available for whatever reason or if yolks aren't enough for hairball control (some cats just seem to need more help with this).
1. Steam, then puree veggies or use veggie pulp from a juicer.
2. Finely chop heart, gizzards, and liver or use a food processor.
3. Mix all ingredients (with hands if need be) and blend well. Can add more water/broth if consistency is too gooey and glue-like.
4. Transfer to storage containers e.g. glass canning jars (leave 1/4-1/2" room on top for expansion), and freeze.
5. At feeding time, warm up by placing glass jar in warm water, or remove metal lid, and place in an oven on the lowest temperature setting, then serve.
Feeding amount: A good guideline is 2-2.5% of ideal body weight. This mix will be quite nutrient-dense because it contains no fillers, so all your 8-10lb cat will need is about 2ish Tablespoons per meal. You might want to add warm water at serving time if the mix is a little too gooey.
If all of this is too much work, you can always order pre-ground mixes from various independent meat farmers or purchase commercial pre-made mixes. They are usually much more expensive of course, but rather convenient. Nature's Variety brand contains only 5% veggies, so it is one of the best IMO. Alas, I don't get paid from any companies though if you know of one or more reputable ones who would like to, do drop me a line because meat is expensive!
"Idiosyncratic nutrient requirements of cats appear to be diet-induced evolutionary adaptations", Morris J.G. Nutrition Research Reviews, Volume 15, Number 1, June 2002, pp. 153-168.
(note: they keep moving this article, and although I try and stay on top of it, please google it in case the link isn't working; here's the abstract, which seems to stay put :)
"Mineral, Amino Acid, and Hormonal Composition of Chicken EggshellPowder and the Evaluation of its Use in Human Nutrition", A. Schaafsma, I. Pakan, G.J.H. Hofstede, F.A.J. Muskiet, E. Van Der Veer, and P.J.F. De Vries, 2000 Poultry Science 79:1833–1838
"Cats Absorb ß-Carotene, but It Is Not Converted to Vitamin A", Florian J. Schweigert, Jens Raila, Brigitta Wichert and Ellen Kienzle, J. Nutr. 132:1610S-1612S, June 2002.
"Dietary ß-Carotene Absorption by Blood Plasma and Leukocytes in Domestic Cats" Boon P. Chew2, Jean Soon Park, Brian C. Weng, Teri S. Wong, Michael G. Hayek and Gregory A. Reinhart Journal of Nutrition. 2000;130:2322-2325.
"In summary, these studies provide the first available evidence that domestic cats can readily absorb ß-carotene across the intestinal mucosa. ß-Carotene also is taken up by peripheral blood leukocytes and is distributed into subcellular organelles, notably the mitochondria. In the leukocytes, ß-carotene may play an important role in maintaining their structural and functional integrity. Therefore, some aspects of the biokinetic uptake profile of ß-carotene in domestics cat are similar to those of humans. This similarity suggests that domestic cats may be an appropriate animal model for studying ß-carotene absorption and metabolism in humans".
Modulation of humoral and cell-mediated immune responses by dietary lutein in cats. Kim HW, Chew BP, Wong TS, Park JS, Weng BB, Byrne KM, Hayek MG, Reinhart GA. Vet Immunol Immunopathol. 2000 Mar 15;73(3-4):331-41.
"These results support the immuno-modulatory action of lutein in domestic cats."
Intestinal Lengths and Transit Times for Digestion: mean retention time of 13 hrs" (another article that keeps changing URL)
Debra L. Zoran, DVM, PhD, DACVIM, "The carnivore connection to nutrition in cats', JAVMA, December 1, 2002 (Volume 221, No. 11)
D. McDonald Zoo Nutrition Advisory Group (NAG), Victoria, Australia.Nutritional Considerations - Section I: Nutrition and Dietary Supplementation, in Clinical Avian Medicine, Harrison G.J. and Lightfoot T.L, 2006
Note - as per Table 4.1.28 in the above section, mice have Ca:P of 1.7:1, rats 1.8:1, and chicken 1.6:1 with chicken containg a lower absolute amount of Ca and P as well.