The failure of the cat to desaturate linoleic acid; its nutritional implications.

In vivo administration of 1-14C-linoleic acid to domestic cats demonstrated that these animals are unable to convert this essential fatty acid to its physiologically active metabolities. This experiment confirms the absence of both the delta6 and delta8 desaturases in the cat, and suggests that this species has a dietary requirement for polyunsaturated fatty acids of animal origin.