Attraction and Ovipositional Response of Screwworms, Cochliomyia Hominivorax (Diptera: Calliphoridae), to Simulated Bovine Wounds1

Abstract

An olfactometer oviposition bioassay was developed to study behavior of the screwworm fly, Cochliomyia hominivorax , in the laboratory. Maximum oviposition (95.5%) occurred when females contacted bovine blood heated to 40°C; also, bovine blood had the lowest mean attractancy (10.3%) in olfactometer tests. Contact with all test materials was necessary to stimulate oviposition. Vat Auid (incubated larval medium containing meat-blood mixture contaminated with larval waste products and microorganisms) had an attractancy of 80.3%, but inhibited oviposition at concentrations greater than 2.5%. Temperature and concentration of stimulants were important factors that affected both the attractancy of the test materials and oviposition in the screwworm fly.