The role of isoleucine in differential egg production by the mosquito Aedes aegypti linnaeus (Diptera: Culicidae) following feeding on human or guinea pig blood

Abstract

1. 1. Egg production by the Newbam strain of Aedes aegypti was significantly greater following feeding on guinea pig blood than on an equal volume of human blood. 2. 2. One prominent difference between the bloods is the lower isoleucine content of human blood. When fed with either whole human blood or red blood cells suspended in saline, both supplemented with isoleucine, egg production by these females increased to the level of those fed guinea pig blood. 3. 3. The addition of isoleucine to guinea pig blood did not increase egg production. 4. 4. A nutritional role of isoleucine in ovarian development, rather than a trigger for the release of egg development neurosecretory hormone (EDNH), was proved by the following: (a) Isoleucine-poor human blood was as effective in causing EDNH release within 2 hr following feeding as was the isoleucine-richer guinea pig blood. (b) A positive correlation exists between the isoleucine content of ingested media and the degree of follicular maturation. (c) In the presence of isoleucine, fat body organ cultures incorporated greater amount of labelled amino acid into soluble protein (vitellogenins) than in its absence. 5. 5. Sufficiency of isoleucine content in the feeding media resulted in less follicular resorption, and hence a higher level of follicular maturation.