US Patent 3,583,871 (granted June 8, 1971) describes an artificial feed for silkworms made from a hydrogel of maize and/or sorghum with soybean solids, which can replace mulberry leaves after the second instar. Examples compare feed compositions, cooking conditions, and particle size by larval weight and cocoon yield, and show that combining penicillin or tetracycline with a macrolide antibiotic protects larvae from flacherie. The patent ends with nine claims and a list of cited references. It was assigned to Ajinomoto Co. and Katakura Industry Co.