OBJECTIVE: The Veterinary Resources Program, National Center for Research Resources, has established a Watanabe Heritable Hyperlipidemic rabbit (WHHL) breeding colony to be used as a resource for investigators. In order to better serve the scientific community, the serum cholesterol and cholesterol and triglyceride values of the colony are to be characterized. METHOD: The proposed course involves bleeding rabbits at weaning, three months, seven months, and 12 months. The serum will be analyzed for lipoprotein cholesterol and triglycerides.