Physiological state and generative growth of whitefish in conditions of recirculating aquaculture systems

Russian. Представлены результаты опытного выращивания сеголетков-двухлетков балтийского сига в условиях УЗВ. Показано, что монодиета и выращивание при температурном режиме с малыми пределами колебаний (16-18 градусов С) не ведут к заметному изменению физиолого-биохимических показателеймолоди, по сравнению с традиционными методами выращивания. Представлены материалы по генеративному росту и обсуждается возможность нормального созревания производителей при заданном технологическом режиме выращивания.

English. In a course of the experimental breeding there were studied underyearlings- two year bions of Baltic whitefish in conditions of Recirculating Aquaculture systems. As a result of realized research there was revealed that monodiet and breeding at temperature with 93 insignificant fluctuation limits (16-18 Celsius degrees) should not cause any noticeable change of physiological and biochemical values of young fish as compared to conventional breeding methods. There was provided the data on generative growth and discussed the possibility of normal maturing of producers at the specified technological breeding conditions. In the context of the ultrasound is possible to grow and formation full broodstock whitefish. Decisive conditions were good nutrition and temperature during periods and subsequent formation of gonad fish maturation. The physiological state of the two-year corresponds to parameters of whitefish in the natural cultivation, which gave reason to hope for a normal gametogenesis of manufacturers. Analysis of the ratio of germ cells in the ovaries of different generations of whitefish showed an increase in the number of previtellogennic oocytes and oocyte in a phase of vacuolization of the cytoplasm. The diameter of the oocytes depending on the growth stage ranging from 80-120 microns to 145-250 microns.