In industrial aquaculture, spawning of t*he Clarias catfish (lat. Clarias gariepinus) is complicated by the fact that it is impossible to obtain sperm due to the physiology of the fish. Fish farmers deal with the problem in different ways. They have to expect natural spawning, do a resection of the gonads or kill and dissect the fish (slaughter). We would like to propose a method for collecting sperm through the puncture of the gonads of the fish. The method is intended to save male broodstock. If the weight of the fish does not exceed 2 kg, the procedure can be performed any anesthesia. There is no need for the fish to be separated from the rest of the broodstock after the surgery. 43 of the 65 stimulated one-year-old males with an average weight of 1250 g have given motile sperm with a volume of 1.5 ± 0.1 ml.

The influence of different temperature regimes (28 ° C and 25 ° C) on the early ontogeny of Clarias gariepinus was studied. Heterochronism in the development of the main systems has been provided: the central nervous system and the digestive system are actively developing, the formation of the cardiovascular, respiratory and genitourinary systems occurs more slowly. The duration of embryonic development within the membranes was 18-22 hours. The initial stages of development changed insignificantly with decreasing temperature. The duration of the larval period was 14 days at 28 ° C and 15 days at 25 ° C. The fry period lasted 30 and 32 days, respectively. In terms of the duration of embryogenesis and the timing of the release of free embryos, the indicators did not go beyond the norm. The percentage of ugly embryos (underdevelopment of the operculum, underdevelopment of the tail, head and fins) was small and amounted to 3.2%, in the first and 4% in the second temperature regime. Incubation at temperatures below the optimum temperature of this species makes it possible to obtain viable offspring, adapted to the change in temperature regime.

The sperm of Russian sturgeon (Acipenser gueldenstaedtii Brandt et Ratzeburg, 1833) was the research object. Acoustic-mechanical influence on sturgeon semen improves fish-biological and reproductive indices of the seminal fluid. The most optimal indices for reproductive cells of male Russian sturgeon are 500 Hz, 90 V with the exposure duration of 1 minute. It has been shown that when a piezo-actuator with a frequency of 500 Hz and an amplitude of 90 V is applied to the sperm mixture with the cryoprotectant, ice crystals are formed later, which may influence the survival of cells after defrosting.