Improving the technology of reproduction of channel catfish Ictalurus punctatus (Raf.) in the conditions of warm-water fisheries

In the process of work on the reproduction of the channel catfish Ictalurus punctatus (Raf.) In the conditions of LLC «Belovsky Fish Industry», the main problem was the timely production of high-quality offspring, associated with differences in preparation for spawning of females and males. In this regard, the purpose of the work: to develop and test various options for carrying out spawning campaigns, including those using various drugs for hormonal stimulation of manufacturers. The results of testing Nerestin preparations in 2006–2008 are presented. In 2006, the drug Nerestin-5x (N5x) was tested. The main problem was identified: 80% of the injected females matured, but the passive males did not start fertilization. It was proposed to adjust the total dose of H5x for females towards a decrease, depending on the degree of their initial readiness, and for males — towards an increase. In 2007, drugs H5x and H7A were tested. A change in the injection scheme of males in 2007 compared to 2006 (an increase in the total dose to the norm of females, but with the use of the drug H5x, and not H6A or H7A during the first two injections) increased the readiness of males for spawning slightly. In 2008, males were brought into the hatchery one month earlier than females, increasing the maturation period of males and changing the temperature rise schedule to prepare for spawning. The drug H7A was used. Despite the increase in the total dose of H7A for males to the total dose for females, their readiness for spawning was still insufficient. To a greater extent, the readiness of males was influenced by an increase in the period of keeping and feeding. The conclusion is drawn that preparations H7 and H7A are quite applicable for artificial reproduction of channel catfish, but the technique of application must be improved by adjusting the conditions of pre-spawning maintenance of producers and the injection scheme.