Preparation of pike-perch breeders (Sander lucioperca Linnaeus, 1758) for spawning, spawning and eggs incubation in experimental spawning units

The article presents the materials on the current state of aquaculture in Russia and in the world, in particular, the biotechnology of breeding and rearing pike-perch in recirculating aquaculture systems. Pike perch (Sander lu-cioperca Linnaeus, 1758) is in high demand among the population. There are shown the results of artificial production of pike-perch offsprings in the experimental spawning units, which make it possible to create the conditions for spawning close to those in the open water bodies. The work included 3 stages: holding pike-perch breeders and preparing them for spawning; spawning; incubation of eggs and prelarvae hatching. Methods for stimulating and spawning pike-perch breeders, as well as a method of eggs incubation in industrial conditions are described. It was demonstrated that all males matured in 24 hours after injection, females ‒ in 28 hours. Incubation of fertilized pike-perch eggs was carried out in the nests of the spawning device. Fertilization of eggs at the stage of gastrulation made 70%. As a result of research work, there have been selected the optimal hydrochemical parameters and fish-breeding and biological characteristics of farming pike-perch spawners, of intensive incubation of eggs under the controlled conditions of a spawning unit. In addition, there have been registered the infectious, parasitic and alimentary diseases, the alternative ways of cure and preventive treatment have been presented. The results of studying the production of pike-perch offsprings in the experimental spawning unit prove the possibility of its using on the industrial scale. The development of a method for reproducing pike-perch in industrial conditions using a special spawning unit will allow obtaining the viable offspring in the controlled environmental conditions.