Influence of Water Type and Commercial Diets on the Production of Anopheles gambiae Giles, under Laboratory Conditions

Abstract

In the present research we investigated the influence of water resources (tap water, pond water and sprint water...) and nutritional quality on egg hatching and larval development of An. gambiae (Diptera: culicidae). Whatever the nutritive quality, the hatching rate was 84 +/- 4 in tap water, 89 +/- 1.4 in pond water and 91.8 +/- 2.2 in spring water. The duration of hatching is 72 hours in tap water and 48 h in spring water. The duration of development (from egg to emergence) is 19.3 +/- 1.1 days in tap water, 12.4 +/- 0.35 days in pond water and 11.55 +/- 0.4 days in spring water. The total death rate was 92% in tap water, 28% in pond water and 22% in spring water. Statistical test shows that the sex ratio at emergence was influenced by the type of water (X2 = 7.9; p = 0.02). The female from tap water laid an average of 11 eggs per female whereas female from pond and spring water laid about 150 eggs per female five days after emergence. Physico-chemical analysis shows that temperature of tap water, spring water and pond water were in average 24.5, 27.5 and 25 degrees C, respectively. Chloride concentration was in average 2.49 in tap water, 0.22 in spring water and 0.32 in pond water. Our observations indicated that spring water constituted the excellent medium for An. gambiae rearing.