In vivo induction of ovarian development inAëdes atropalpusby a head extract fromAëdes aegypti

Abstract

Aëdes atropalpus is an autogenous mosquito, i.e. adult females will undergo complete oocyte maturation without the benefit of a bloodmeal. Ovarian development is completely inhibited if these animals are decapitated within 6 h of adult emergence, suggesting that a factor from the head is required for vitellogenesis to proceed. Ovarian development, including vitellin deposition, was initiated in more than 80% of the decapitated A. atropalpus females after they received an injection of an aqueous saline cell-free extract prepared from heads of non-blood-fed anautogenous A. aegypti adult females. The active factor(s) in this extract appears to be a relatively stable macromolecule(s) of between 3500 and 12,000 daltons.