Variation in the Efficacy of Several Predator Gut Content Immunoassays,

Five different immunoassay formats were examined for their ability to detect a minute quantity of prey remains in predator guts. The convergent lady beetle,Hippodamia convergensGuérin-Meneville, that had consumed either one or five pink bollworm,Pectinophora gossypiella(Saunders), eggs was evaluated by the following immunoassays: three variations of enzyme-linked immunosorbent assay (ELISA), a dot blot, and a Western blot. Sandwich ELISA, dot blot, and Western blot were the most sensitive immunoassays based on the proportion of individual predators scoring positive for prey remains. The direct ELISA and indirect ELISA were ineffective at detecting prey in the predators. The advantages and disadvantages of each immunoassay format are discussed.