Feeding behaviour of female Aedes aegypti: effects of diet temperature, bicarbonate and feeding technique on the response to ATP

Abstract

The effects of variation in diet temperature, mouthpart deployment and the addition of bicarbonate to a saline-ATP diet were investigated for their effects on amount ingested and diet destination in female Aedes aegypti (L.). Mouthpart deployment was achieved by having the insects feed through a membrane, or from a free-liquid surface with mouthparts intact, or with the fascicle separated from the labial groove.Under the 'feeding through membrane' protocol, a 6-fold increase in the percentage of Aedes feeding on ATP-diets was recorded at 37°C compared with 21°C. Bicarbonate (9.5 or 1 9 m~) induced a 3-fold increase in numbers feeding at both 21°C and 37°C. Neither diet temperature nor bicarbonate content appeared to affect meal size. The pH of all diets was adjusted to 7.0. Diet was directed primarily to the midgut for all diets tested under this regimen, with the exception of the saline-ATP-19 mM NaHC03 at 37°C which caused the diet to be directed primarily to the crop.Under the 'feeding without membrane through feeding tube' protocol, females showed little control over diet destination. Female Aedes aegypti exhibited no strong response to ATP when the mouthparts were immersed in 21°C diets in feeding tubes and few of these insects ingested large meals. The addition of bicarbonate to the ATP diets did not enhance feeding under these test conditions.

Development and physiological effects of an artificial diet for Wolbachia-infected Aedes aegypti

“…Human or Cow blood fractions (Plasma and Red Blood Cells) were obtained by centrifuging whole blood at 1500 rpm for 5 mins. ATP (Sigma Aldrich A2383-5 g, Conc Final = 2 mM) was added to all diets as a phagostimulant 30 . Stocks of APS were stored at 4 °C, while stocks of ATP were stored at −30 °C at a concentration of 100 mM.…”