Effects of Prolonged Oviposition-site Deprivation on Fecundity, Egg Viability and Blood-feeding Activity of Gravid Aedes aegypti Females from Northern Côte d’Ivoire

Abstract

Prolonged dry seasons may restrict access to suitable oviposition sites for gravid Aedes aegypti females, potentially affecting reproductive performance and feeding behaviour. This study assessed the effects of delayed oviposition on fecundity, egg viability and blood-feeding activity in females originating from Korhogo, northern Côte d’Ivoire. Wild immature stages were collected from artificial and natural breeding sites and reared under controlled insectary conditions. After emergence and two blood meals, gravid females were allocated to eight batches of 40 females and subjected to oviposition-site deprivation ranging from 0 to 70 days. Fecundity was determined from the number of eggs laid after access to an oviposition substrate, whereas egg viability was assessed using hatching and adult emergence rates. Blood-feeding activity was monitored over 12 feeding sessions. Mean fecundity remained stable across oviposition-delay treatments, ranging from 114 to 117.79 eggs per female, with no significant difference among batches (H = 29.481; p = 0.103). In contrast, hatching declined from 87.22% in the control to 45.37% after 70 days, and adult emergence decreased from 90.05% to 68.19%. Blood-feeding activity also progressively declined across sessions. These findings indicate that prolonged oviposition-site deprivation may preserve egg-laying capacity while reducing offspring viability and modifying blood-feeding activity in gravid Aedes aegypti females under simulated dry-season conditions.