A system of rearing insect biological control agents (BCA) comprising feeding them nutrients essentially derived from processed insect eggs (PIE) is disclosed. The insect eggs may be derived as a by-product from medfly reared for sterile insect technique (SIT) or any other appropriate species, or the eggs may be specially produced for the purpose. The present invention also discloses a system of rearing BCA's comprising a mixture of PIE and at least one other insect diet. A factitious diet composition comprising PIE suitable for providing nutrients to a BCA and a method of producing PIE from insect egg supplies derived from by-products of insect control programs such as SIT is also provided. A method of preparing the PIE for long-term storage and distribution is also disclosed in the present invention.
