Larval and adult environmental temperatures influence the adult reproductive traits of Anopheles gambiae s.s.

Abstract

Background: Anopheles mosquito life-history parameters and population dynamics strongly influence malaria transmission, and environmental factors, particularly temperature, strongly affect these parameters. There are currently some studies on how temperature affects Anopheles gambiae s.s. survival but very few exist examining other life-history traits. We investigate here the effect of temperature on population dynamics parameters. Methods: Anopheles gambiae s.s. immatures were reared individually at 23∈±∈1 °C, 27∈±∈1 °C, 31∈±∈1 °C, and 35∈±∈1 °C, and adults were held at their larval temperature or at one of the other temperatures. Larvae were checked every 24 h for development to the next stage and measured for size; wing length was measured as a proxy for adult size. Females were blood fed three times, and the number of females feeding and laying eggs was counted. The numbers of eggs and percentage of eggs hatched were recorded. Results: Increasing temperatures during the larval stages resulted in significantly smaller larvae (p∈=∈0.005) and smaller adults (p∈