Sugar Feeding Affects the Male Contribution in Reproduction in Aedes Aegypti

Juvenile hormone (JH) is crucial for the stimulation and progression of oogenesis from emergence to the previtellogenic resting stage in female Aedes aegypti mosquitoes. Juvenile hormone has been suggested to be among the many substances transferred form the male accessory glands to the female during copulation but no evidence for this has previously been provided. Quantification of JH III in the accessory glands of males and in the bursae copulatrix and spermathecae of mated females was performed using HPLC-FD. These amounts were measured in relation to the quality of adult sugar feeding in the male. The effect of this variable transfer was measured on two fecundity markers that occur during the previtellogenic stage of oogenesis, specifically follicular resorption and ovarian lipids. Male mosquitoes provided with 20% sucrose contained ~ 60% greater amount of JH in the accessory glands and transferred 4 fmol more JH during copulation than males provided with 3% sucrose. These differences resulted in a nearly 40% reduction in follicular resorption and an approximate 3-fold increase in lipid content in the ovaries of mated females during the previtellogenic stage. These results suggest that the contribution of JH from the male is dependent on the quality of nutrition obtained during adult sugar feeding. Female fecundity is likely responsive to these variable previtellogenic effects, possibly resulting in a difference in the number of eggs laid. Improvements in female reproductive output may have wider implications in the transmission of diseases attributed to this important arbovirus vector.