With the bone to meat ratio of rabbit being high there is definitely a lot of calcium in rabbit. At the same time, the phosphorous levels in rabbit are about 3x higher than chicken. From there I guess I need to do some math to figure out.
Time out!
OK, after just checking some things out, there is a problem with the assumption bone to meat ratio of rabbit is higher than chicken. Could be true for wild game rabbit, but it's not true of anything we are buying to feed our cats. With that as a baseline for Dr Pierson's rabbit recipe, the rest is challenged in it's concerns on how to formulate a rabbit recipe. For our purposes, the bone to meat ratio are close enough to the same for not dancing on the head of a pin to discern any differences. Just the same rabbit does contain 3x the amount of phosphorous.
From there I guess I am still sent back to the drawing board. I don't believe any food in nature is perfectly pre-packaged for a cat. There is the nutritional value of what their prey may be, but there is also what they leave behind. Smaller prey and they may eat the whole thing, larger 4-6lb rodents probably not and even a 45lb serval would be eating a whole rabbit or chicken in one sitting.
Back to my rabbit recipe, and the break down of organs to whole rabbit is as follows. 6 lbs whole rabbit, approximately .5 lbs rabbit liver, .25lbs rabbit kidneys and .25 lbs of rabbit hearts. I guess I could change the whole rabbit to organ ratio, although I can't really deviate from the pre-packaged percentages of rabbit organs. My cats love it, but it's only about 40% of their diet, then they also have higher fat content foods like chicken and duck.
One other part of this whole equation is that we breed these super chickens to have lave larger breasts, higher meat to bone ratios and basically just larger chickens. At issue is that despite these chickens being much larger, they don't really pack in any more nutritional value for the extra weight they carry. Same has to be true of rabbits who have been farmed for a long time now, and are far removed from the wild game they once were. In other words, I don't think I know anything more than when I started.