Sterilizing Procedures and Agents, Antibiotics and Inhibitors in Mass Rearing of Insects

Abstract

Months of costly effort may be wasted when disease strikes laboratory colonies of insect. High-density populations tend to maximize this threat by facilitating dispersion of microbes through crowding and lowered sanitation. It is not my purpose to deal with physical factors of the rearing environment which influence insect health. SUch factors as excessive heat, wet food or change of host plant, abrasives in food, starvation, anoxia, and trauma are recognized as capable of activating microbial disease in certain insects. Instead, I shall stress sterilizing agents such as heat, irradiation, and chemicals, as well as other agents which are used to prevent or eliminate disease in insect colonies. Familiarity with aseptic techniques and other microbiological routines is not a usual part of entomological training. However, such skills are being increasingly exploited in mass rearings for: 1. Sterile male or parasitoid release, pheromone studies, and other approacheds to pest control; 2. nutritional studies; 3. gnotobiotic studies; and 4. in-vitro tissue and organ culture. The germfree route is now sufficiently well traveled to justify exposing students to its advantages. I have tried to gather the experiences of investigators working on many species of insects. Though the covereage is far from exhaustive it is perhaps sufficiently representative to provide a useful summary of available techniques and agents for keeping insect populations free of disease int he laboratory.