Experience in the formation of a repair and breeding stock of thorns (Acipenser nudiventris) for reproduction purposes on the basis of Halyk Balyk LLP in Almaty region

In modern conditions due to the intense anthropogenic impact on the ecosystem, and accordingly on the habitats of valuable fish species, there is a landslide reduction in spawning populations of thorn in the Ili-Balkhash basin. The issue of preserving this species is discussed through the formation of repair and breeding herds from “wild” individuals, domestication in controlled conditions of fish farms. Only under controlled conditions are there opportunities for the formation of productive herds of endangered fish species. The production facilities of Halyk Balyk LLP were used to carry out work on the reproduction of young thorns and the formation of repair and brood stock of thorns. Throughout the entire period of thorn cultivation, direct-flow water supply from an artesian well was used in the pools of Nalyk Balyk LLP. The water temperature in the pools ranged from 15.0 to 15.50 °C. To increase the immune status in order to prevent stress, courses of vitamin C, B vitamins, and viusid - vet feed additives were regularly administered as needed. The use of such a feeding scheme allows to increase the growth rate of fish, increases the survival rate of fish and improves their physiological condition, fish become more resilient. The adaptation of “wild” individuals of the thorn takes place in a shorter time. Based on the determination of the growth and dynamics of the mass of adaptable individuals, it was found that the habituation to new conditions and artificial feeds is slow, only in the second month the fish begins to eat fruitfully. The survival rates of the domesticated thorn for the entire growing period were 100%.