| The optimum calcium/phosphorus ratio is the same for a pup or an adult. The optimum is 1.3:1 and commercial dog foods formulated to meet AAFCO standards will have this ratio.
What differs is the amount of calcium and phosphorus needed by growing dogs and adults. Young pups require a greater amount of calcium and phosphorus than adults do. It is also imperative that the ratio for a pup be as close to optimum as possible.
After about 7 months of age, a dog develops the ability to excrete or take up more of the calcium offered as needed and the ratio isn't quite as critical. It can be anywhere from 1:1 to 2:1 and not cause harm in a healthy dog, though one should always strive to meet the optimum ratio.
Since I make my Maggie's food myself and her foods are severly limited by her allergies, her calcium/phosphorus ratio has ranged from 1.2:1 to 1.7:1 over the last four years, with no adverse effects. Since Dresden has no allergies, it is much easier to manipulate foods and supplements to keep her ratio close to optimum.  |