Skin surface lipids of the horse

Skin surface lipids from the sides of male and female horses ( Equus caballus ) were collected in acetone and analyzed by thin layer chromatography and gas liquid chromatography. The sole components in both sexes were cholesterol, cholesteryl esters and the lactones of 32‐, 32‐ and 36‐carbon ω‐hydroxy acids, each including a methyl group in the n−1 position. Most of the lactones were mono‐unsaturated (either n−8 or n−10), but small amounts of saturated and dienoic species were present. A pooled sample of the skin surface lipids contained 14% cholesterol, 38% cholesteryl esters and 48% lactones.