Фауна моногенетических сосальщиков рода Dactylogyrus молоди карпа в прудах Оренбургской области

Abstract

Monogenetic flukes, as a kind of the parasites with a direct development cycle, pose a particular danger to the fish farms. They adapt easier to new conditions due to the absence of intermediate hosts in their life cycle. Among the representatives of the class Monogenea flukes Dactylogyrus parasitize on carp’s gills. Dactylogyrosis are conditionally pathogenic ectoparasites that are dangerous for the young fish. The work presents the results of the parasitological studies of gill arches of carp juveniles grown in ponds of the Orenburg region. There are four species of dactylogyride found: Dactylogyrus vastator, Dactylogyrus extensus, Dactylogyrus achmerowi, Dactylogyrus anchoratus. Only two species of monogenetic flukes were found in fish most often at the early age: Dactylogyrus vastator and Dactylogyrus extensus. The comparison of the infestation of individual gill arches of carp juveniles with dactylogyrids showed that the helminths distribution is not the same in different areas of the gill apparatus. The dactylogyrids proportion on the gill petals of the second gill arc is greater than on the first and third arcs. The helminths proportion found on the petals of the first gill arc does not differ from the worm proportion on the third gill arc. When analyzing the distribution of dactylogyrids by gill sectors, it was found that from 58.9 to 66.0% of monogenetic flukes localize in the middle sector of the gill apparatus of fish, the most strongly washed area of gills. The worm proportions in the abdominal and dorsal sectors differ slightly, except for Dactylogyrus achmerowi, where the helminths proportion in the abdominal section of the gills is almost half less than in the dorsal sector, 14.0 and 27.0%, respectively.