Pigment compositions useful for supplementing marine animal feeds comprise comminuted Haematococcus cells treated to degradation of carotenoids, typically by coating or by combination with an anti-oxidant. Encysted Haematococcus cells are ground at cryogenic temperatures, typically by combining the cells with liquid nitrogen in a suitable impact mill. The resulting powder has an average particle size below about 5 mu m. Usually, the Haematococcus will be grown in large-scale culture ponds under controlled conditions.
