Abstract
Laboratory and field test methods are described for assessing the activity of chemicals for the control of sheep blowfly Lucilia sericata (Meig.). The essential properties for a sheep blowfly insecticide are discussed. Screening results for several series of sulphonamides and disulphonamides, with and without N‐substituents, are presented. Although some disulphonamides showed high activity, none had the necessary persistence for use in a sheep‐dip.