THE EFFECT OF VITAMIN D-DEFICIENT DIETS CONTAINING VARIOUS CA:P RATIOS ON CATS 12

The few nutritional studies of cats available indicate that the nutritional requirements of cats may differ from those of other species in many details. Gershoff et al. ( '57) have reported an inability of cats to convert carotene to vitamin A. They also found that the absorption of vitamin A by cats was related to the fat content of the diet. These workers and others (Krehl et al., '55; daSilva, '50) have reported that cats appear to require high-fat diets and they routinely feed cats purified diets containing 25 to 30 % of fat. Most studies of experimental rickets have been conducted on rats, a species in which rickets cannot be produced unless the ratio of dietary calcium and phosphorus is altered. The desirability of stud ies of rickets in other species in addition to the peculiarities in the cat's need for fat and fat-soluble vitamins led to th