NATURAL VARIATION IN BLOOD-FEEDING KINETICS OF 4 MOSQUITO VECTORS

The blood-engorgement kinetics of Anopheles aquasalis, Aedes aegypti, Haemagogus janthinomys, and Culex quinquefasciatus were determined und er laboratory conditions using females collected from three field site s in Trinidad. Most An, aquasalis, Ae. aegypti, and Hg, janthinomys co mpleted probing within 70 s but Cx. quinquefasciatus averaged >180 s. Anopheles aquasalis (67.0 s) had the shortest gut filling time while C x. quinquefasciatus had the longest gut filling time (222.8 s). Aedes aegypti and Hg. janthinomys had similar gut filling durations, 87.7 s and 90.4 a, respectively. More than 70% of An. aquasalis, Ae. aegypti, Cx. quinquefasciatus, and Hg. janthinomys showed prediuresis. Anophel es aquasalis exhibited the shortest mean duration of prediuresis (77.3 s) and Cx. quinquefasciatus the longest (526.9 s). Most individual mo squitoes spent less time filling their guts than in prediuresis. Overa ll, An. aquasalis exhibited the shortest total feeding time (135.7 s) and Cx. quinquefasciatus the longest (661.9 s). Individual An. aquasal is mosquitoes showed a high degree of variability in their ability to agglutinate human erythrocytes immediately upon blood engorgement, wit h individuals agglutinating <25% of the ingested erythrocytes and othe rs greater than or equal to 90%. Among Ae. aegypti and Cx. quinquefasc iatus, the proportion showing agglutination varied from 0% (67% and 69 % respectively) to <50%. The parity of the field collected mosquito ve ctors had no significant effect on probing, duration of blood-feeding, duration of prediuresis, or erythrocyte agglutination. The inter- and intra-specific variation in blood-feeding and erythrocyte processing observed for the four vector species collected from the field in Trini dad are described in terms of vector competence and evolution of these behaviors.