Study on mosquito ovary using transmission electron microscopy
Milagros M Greif
The study focuses on the ovaries of mosquito using transmission electron microscopy. Mosquito that were used comprised of six different strains, namely: Culex pipiens Complex, Aedes aegypti, Aedes vexans, Ochlerotatus cantans, Ochlerotatus rusticus collected from the Philippines and Germany. A meal of blood in the mosquito can alter a series of changes in the cell structure that leads to the formation of a mature egg. After the mosquito has taken a blood meal, some prominent changes occur in the epithelial follicles. The very prominent changes that occur are the development of large inter-cellular spaces and a decrease in desmosomal connections. Several numbers of microvilli covered the area of the oocyte facing the epithelial follicles of which during seven hour after blood meal, push towards the extra-cellular spaces created by the separation of the epithelial follicle cells. The microvilli vary in length and are not regularly distributed like those of the typical intestinal epithelium. A unit membrane is seen which later fuses to form a yolk. A meal of blood or controlled diet leads to a series of changes in cell structures in the reproductive organ of female mosquitoes that quickly results to the formation of matured eggs. Another prominent changes observed in the ovary of mosquitoes having blood meal is the presence of various un-oriented microvilli in the area of the oocyte which is adjacent to the epithelial follicles. These microvilli can also be observed in ovary of mosquitoes having no blood meal but they are smaller in size. Furthermore, pits or vesicular bodies are developed after a mosquito has taken a blood meal.