Pledger, Richard A. (Plum Island Animal Disease Laboratory, Greenport, N. Y.) and Jerome Polatnick. Defined medium for growth of foot-and-mouth disease virus. J. Bacteriol. 83:579-583. 1962.-Foot-and-mouth disease virus, grown in primary bovine calf-kidney cell layers with a defined medium containing glucose as the only organic substrate, produced virus titers equivalent to those obtained with complex media containing serum and lactalbumin hydrolyzate. Mannose was the only other substrate examined that could replace glucose. Krebscycle intermediates did not or only partially supported viral replication. Phosphate was also found essential for reproduction of foot-and-mouth disease virus. The rate of heat inactivation of foot-and-mouth disease virus in defined medium was more than twice that in complex medium. This, however, did not interfere with the usefulness of the defined medium for short-term biochemical investigations.