Comparative Studies On Ultrastructure Of Spores Of Three Myxosporeans Parasitic In Freshwater Fish

This work mainly deals with structures and ultrastructures of three species of myxosporeans parasitic on the gills of Carassius auratus and Peleobagrus fulvidraco in culture water and natural water from Chongqing, China. These 3 species of myxosporeans, Myxobolus ampullicapsulatus Zhao et al, 2008; Henneguya doneci Schulman, 1962; Unicauda pelteobagrus Ma, 1975, submitted to Myxobodiae family, Bivalvulida order. In this study, the descriptions of these myxosporeans are in accordance with the guidelines contributed by Lom & Arthur (1989), while the taxonomy system and research methods are followed the ones presented by Zhao & Song (2003). The reseach mainly covered the morphology and taxonomy of three species of myxosporidia by both light microscope and electron microscope from the perspective of features which occurred in parasitism and development progress in order to enrich more information on them.In section 1, overview of myxosporean ultrastructure on the vegetative and mature spores, nutritionl developmental has done. In section 2, materials and methods of the scanning electron microscope samples of the production methods improved, the first fixed after centrifugation, the use of anti-off slide, using burette disperse spores, and samples were pushed chip operations, results showed that the observed image clear, body distribution, body surface mucus without coverage, the surface of the body clear. In section 3, study on microscopic and ultrastructure of the three species of myxosporeans, Myxobolus ampullicapsulatus, Henneguya doneci, Unicauda pelteobagrus, were done. Myxobolus ampullicapsulatus Zhao et al, 2008 have two nuclei, fat droplets, spherical electron dense, rich mitochondria, endoplasmic reticulum, ribosomes, refractive granuless and black zone etc.; Henneguya doneci composed of spore shells, polar capsule and sporoplasm three parts. Spore shell formed by the two shell valve, in the ridge of the two shell valve thickening. Two shells have an electronic transparent at a valve connecting, transparent area of mucus material, the front of spores with two pear-shaped polar capsule. In the quality of the spores can also observed that a large number of mitochondria, the endoplasmic reticulum (ER), an iodinophilous vacuole, such as a large number of unknown cystic vesicles structure. The back-end of Unicauda pelteobagrus has a tail; the tail is lap processes in developmental process of spore. Development is bisporus type, and to observe the cyst and inter-organizational exchanges.