Influence of nutrition during previtellogenesis on the follicular development in the Asian Tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae).

Abstract

Dengue fever poses a global public health threat, with 2.5 billion people at risk of infection each year. Because the Aedes albopictus is the primary vector of dengue, it is closely monitored and handled. The efficiency of Dengue eradication is strongly dependent on understanding a female mosquito's physiological age. This study addresses key entomological issues about the impact of previtellogenic nutrition on egg production mechanisms. Ovarian development included two distinct periods: previtellogenesis and vitellogenesis. Sugar intake during previtellogenesis influences the size of the blood meal. The major parameter influencing the vitellogenesis process is the presence of a hematophagous feeding event following sugar concentration. Upon subjecting female mosquitoes to sucrose, the ovarian follicles entered the third phase of previtellogenesis. Once females feed on blood following sucrose, ovarian development enters the vitellogenesis, and the oocyte cytoplasm reveals that the yolk granules are organized in one or two rows like a crown, increasing oocyte size. Females fed 15% sucrose before a blood meal, have the largest vitellogenic growth, and follicular size, which is seven times greater than those fed water only. Fecundity increased by 78.7% by adding 7% sucrose to the diet. Mitochondria within oocytes increase, most likely due to their transportation from the nurse cells, where the yolk is synthesized. This study describes in detail the histological alterations detected in the ovaries during the previtellogenesis as well as those associated with yolk formation, suggesting that yolk protein deposition in the oocyte is associated with blood meal, independent of sucrose feeding. RESEARCH HIGHLIGHTS: Adult nutrition during previtellogenesis significantly impacts various biological parameters and the physiological age of adults of Aedes albopictus. Female mosquitoes experienced significant growth in vitellogenic development, vectorial capacity, and follicular size after consuming a diet with 15% sucrose before a blood meal.