Submitted to: Neotropical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/20/2006
Publication Date: 12/1/2006
Citation: Berkebile, D.R., Sagel, A., Skoda, S.R., Foster, J.E. 2006. Laboratory environment effects on the reproduction and mortality of adult Screwworm (Diptera: Calliphoridae). Neotropical Entomology. 35(6):781-786. Interpretive Summary: The New World screwworm is mass reared for the eradication of the insect using sterile insects. New methods are for rearing have reduced the cost of the eradication program. We examined the effect of temperature, diet and population density on the reproduction and mortality of laboratory screwworms. The population densities that we compared had not effect on reproduction or mortality. The use of a protein diet increased egg production at all temperatures. Diet did not effect egg hatch or female mortality but male mortality was increased when fed a protein diet at certain temperatures. High temperatures decreased reproduction and increased mortality. Exposing the flies to one hour of light each day had a favorable effect on the rearing of screwworms.
Technical Abstract: The New World screwworm, Cochliomyia hominivorax, is mass reared for screwworm eradication initiatives that use the sterile insect technique. New methods for rearing have helped to reduce the cost of the eradication program. We examined the effect and interaction of three temperatures (24.5, 29.5 and 34.5º C), two diets (carbohydrate and carbohydrate + protein) and three population densities (300, 400, and 500 flies/cage). Egg production, egg hatch, number of observable fertilized eggs, mortality (male and female) and ovarian development were monitored. The three population densities did not affect any of the parameters monitored. The use of the protein diet increased egg production at all temperatures. Diet did not affect egg hatch or female mortality. Male mortality was significantly greater when fed the protein diet and reared at 24.5 and 34.5º C. Egg hatch was significantly less when the flies were reared at 34.5º C. When exposed to high temperatures (37 and 40º C) egg production, egg hatch, fertility and mortality were adversely affected. At the higher temperatures, yolk did not adequately form during oogenesis. Short photoperiod (1 L: 23 D) increased egg production, egg hatch, fertility and lowered mortality when compared to the normal rearing photoperiod (12 L: 12 D).