Exclusive towards the cat's metabolism is The shortcoming to convert carotenoids to vitamin A; incapability to synthesise enough vitamin D; lack of ability to synthesise niacin from tryptophan, incapacity to synthesise cysteine, citrulline, and methionine; and an intolerance to glutamic acid.[fifteen] [90] Linoleic acid can not be converted by cats https://petskyonline.com/