The Effects of Nutrition on Survival and Fecundity in Florida Mosquitoes. Part 4. Effects of blood source on oocyte development1

Abstract

Females of 6 species of Florida mosquitoes were maintained on 10% sucrose solution for 11 days after emergence and then allowed to blood-feed to repletion on 7 vertebrate hosts. Blood-fed females were analyzed for weights and calorie intake, oocyte development and eggs laid. Within any particular species or between the different species of mosquitoes, there were no clear-cut relationships between the dry weight and caloric value of the ingested blood and the number of oocytes developed or the number of eggs laid. The caloric value of the ingested blood was 30% to 50% less than that present in the whole (venous) blood of its vertebrate hosts. In general, avian blood did not promote development of a greater number of oocytes or oviposition of more eggs than mammalian blood on a per mg basis in different species.However, differences were observed only when chicken blood and human blood were compared on a per mg basis; e.g., An. quadrimaculatus, Ae. aegypti, Cx. nigripalpus and Ps. columbiae developed 18% to 38% more oocytes per mg of chicken blood than per mg of human blood. The reverse was true in Aedes sollicitans, and almost no differences were observed in Aedes taeniorhynchus. Among the first 4 species, ingested blood agglutinated within 30 min. in An. quadrimaculatus, whereas it coagulated within 30 min. in the other 3 species, which resulted in rapid separation of serum from ingested blood in the midgut. It is suggested that absorption of the serum components resulted in immediate initiation of oogenesis in a large number of oocytes, while promotion to maturity of the initiated oocytes followed the digestion of coagulated blood. The higher titer of DL-isoleucine in chicken blood, compared with that in human blood, probably was responsible for the development of more eggs in the 1st group of mosquitoes, while in the 2nd group, in which coagulation of blood was delayed, substantial amounts of blood were defecated and consequently did not partake in the development of oocytes.