When hippos are upset, their sweat turns which color

Hippos secrete a red, oily substance often called 'blood sweat' though it's neither blood nor sweat. This secretion contains pigments that turn red and eventually brown, acting as a natural sunscreen, antibiotic, and moisturizer. The red color comes from two pigments: hipposudoric acid (red) and norhipposudoric acid (orange), which protect the hippo's skin from sun damage and infection.