Factors affecting ova development in anopheles atroparvus

Abstract

There are certain environmental factors which have been reported to affect ova development in anophelines. Data are needed to quantify these observations. The purpose of this research was to obtain data to confirm the reported effect of temperature, light, blood source, and feeding time on ova development in Anopheles atroparvus. The pattern of ova development in all the experiments conducted was as follows: first there was a slow elongation up to the first peak, then there was a rapid growth period during which the ova reached their maximum lengths, second peak. Shortly after the maximum length was reached a decrease in length due to bending of the ova followed. Critical length in this research was determined to be the maximum length, and it was used as a means of comparison among the experiments. The results in this research indicate that at a higher temperature ova reach the maximum length faster than at a lower temperature. Optimal lighting condition for the ova development is twelve hours of light and twelve hours of dark. There is a change in the rate of ova development when a different host is offered. Ova in mosquitos offered a guinea pig host reach the maximum length faster than when human host is offered. Feeding time may have an effect on ova development. A.M. feeding may be preferable to P.M. feeding. A very high temperature causes some reduction in egg viability. This probably is not advantageous to the organism.