Zinc deficiency in the cat.

Two experiments were conducted to produce Zn deficiency in, and to establish approximate Zn requirements of, the cat. In experiment 1, soy protein (SP)-based diets were fed for 8 months: diet 1, basal, without added Zn, 15 ppm; diet 2, basal, 15 ppm Zn plus 2% CaHPO4; and diet 3, basal with added Zn, 67 ppm. Gross Zn deficiency symptoms were not observed, although spermatogenesis in cats fed diets 1 and 2 was abnormal. There were no differences in food intake or growth rate between treatments. Mean plasma zinc levels (micrograms/100 ml) for cats fed diets 1, 2 and 3 were 55, 47 and 89, respectively. In experiment 2, the SP was washed with EDTA. Ten 8-week-old kittens were fed the following diets for 14 weeks: diet 4, SP without Zn, 0.7 ppm Zn; diet 5, containing 52 ppm Zn; or diet 6, an amino acid diet, 4.8 ppm Zn. Mean food intake (g/day) and weight gains (g/day) for cats fed diets 4, 5 and 6 were: 17.2, 0.4; 55.0, 19.5; and 31.5, 10.0, respectively. Mean plasma Zn levels (micrograms/100 ml) and liver Zn (ppm) for cats fed diet 4 had poor coats characterized by thinning and slow hair growth and scaliness of the skin and ulcerations of the buccal margins. The cat's requirement for zinc is probably between 15 ppm and 50 ppm.