Epizootic aspects of young carp contamination with Dactylogyrosis in the ponds of the Orenburg region

Abstract

Modern fish farming having intensive forms of farming provides for feeding fish with artificial feed, fertilizing ponds and compacting fish planting in nursery, finishing and wintering ponds. This leads to close contact of cultivated fish and, in this regard, favorable conditions for the pathogens accumulation in ponds, the distribution of infectious and invasive diseases. Invasive diseases are a significant danger among diseases including pond fish dactylogyrosis. Dactylogyrosis are monogenetic suckers, parasites with a direct development cycle, live on the fish gill filaments, belong to conditionally pathogenic parasites and pose a serious danger to young fish. Despite a fairly complete study of the biology of carp dactylogyrid, a number of questions regarding the formation of the parasitofauna of these young fish in the early stages of development - the most vulnerable period of their lives - remain little covered in the literature. The work presents data on the Dactylogyrus types found in young carp in the nursery ponds of the Orenburg region, the invasion extensiveness and intensity. 4 species of monogenetic suckers have been found: Dactylogyrus vastator, Dactylogyrus extensus, Dactylogyrus achmerowi, Dactylogyrus anchoratus. Among the four species of Dactylogyrosis, only two species, Dactylogyrus vastator and Dactylogyrus extensus, were found most often and from an early age, two other species were found in older fish, 20 and 25 days of age with little invasion extensiveness and intensity.