Complete developmental cycle of Myxobolus pseudodispar (Gorbunova) (Myxosporea : Myxobolidae)

Myxobolus pseudodispar (Gorbunova) is a common parasite of the muscle of ro ach, Rutilus rutilus L., whereas its actinosporean development occurs in tw o oligochaete alternate hosts. This paper reports the complete developmenta l cycle of this parasite in the oligochaete alternate host Tubifex tubifex and the roach. In laboratory experiments, parasite-free T. tubifex specimen s were infected by myxospores of M. pseudodispar collected from roach in La ke Balaton. Parasite-free roach fingerlings were infected with floating tri actinospores (TAMs) released from oligochaetes on day 69 after challenge. Y oung plasmodia and spores in roach were first recorded on day 80 post-expos ure (p.e.). Myxospores collected from experimentally infected roach initiat ed a new development in T. tubifex and the resulting TAMs infected roach. N o infection of roach resulted from feeding oligochaetes containing mature t riactinospores.