Ultrastructure of normal and JHA-treated eggs of the soft tick Argas persicus (Oken)

The ultrastructure of normal development and JHA-treated egg was examined with the transmission electron microscope. In newly oviposited egg, the chorion consists of exo- and endochorion. Between the chorion and plasma membrane lies vitelline (envelope) membrane, a thin non cellular membrane. The periplasm is free of the yolk spheres with contains vesicles of various sizes and lipid inclusions. The endoplasm is rich in yolk spheres, mitochondria, lipid inclusions, dense vesicles and vacuoles. In 48 h-old egg, cleavage nuclei was seen migrating to the periphery of the egg. The ooplasm around the nuclei contains vesicles, endoplasmic reticulum and few mitochondria. The blastoderm cells contain many organelles and inclusions. Secondary vitellophages and pole cells were observed. In 96 h-old egg, the germ band is formed. It consists of two layers, ectoderm and mesoderm. Amnion and serosa were visible. At (0-1 hour) eggs post-treatment with JHA (Admiral), no real effects was observed except for vacuolation of endoplasm; while at 48 h & 96 h-old post-treatment of eggs, great deterioration were seen which ended by degeneration and lysis of cell components leaving cell debris, vacuolation of nuclei, iregular shape of nuclear membrane and dispersed chromatin material.