Special towards the cat's metabolism is The shortcoming to transform carotenoids to vitamin A; incapacity to synthesise enough vitamin D; lack of ability to synthesise niacin from tryptophan, lack of ability to synthesise cysteine, citrulline, and methionine; and an intolerance to glutamic acid.[15] "We started off getting Diamond Naturals for https://www.petskyonline.com/bird-supplies/