Preparation and stability of animal feed mixtures dosed with rotenone

Studies at Midwest Research Institute for the National Toxicology Program show that rotenone/animal feed mixtures prepared by dry-mixing are more stable than mixtures produced by dosing the feed with alcoholic solutions of rotenone and then stripping the solvent. Also, recoveries of rotenone from the dry mix feeds are higher than those from feeds dosed by the solution method. A simplified analytical method from one previously reported for rotenone in feed is described.