WWW.WAS.ORG • WORLD AQUACULTURE • JUNE 2013 57 times followed by a final selection. The maintenance of optimal heterogeneity and decrease of probable inbreeding during broodstock collection was achieved by fully renewing broodstock every 4 years (8 reproductive cycles) with an annual change of 25-30 percent of breeders with different reproductive origins: 10 percent from hatchery broodstock, 10 percent from the wild and 10 percent from females and cryopreserved sperm. At the Southern Scientific Center of the Russian Academy of Science (SSC RAS), an experimental fish breeding complex allows year-round investigations, independent of weather. The complex consists of 9-m3 tanks for breeders, 2-m3 tanks for recuperation groups (i.e. juveniles chosen to relieve spent broodstock), 1-m3 tanks for fry, tanks for artificial wintering, cooling systems, and filtration systems for maintenance of optimal hydrochemical and hydrological regimes. There is a place for long-term cryostorage of frozen sperm and other special equipment (Figs. 1-5). We have developed a method of cryopreservation of cells using electrostimulation, which gives a high proportion (90-95 percent) of live sperm after thawing. A sperm cryobank is used in the formation of several sterlet broodstocks. In this facility, the development of sterlet broodstock was maintained in two lines: from imported breeders of Volga and Don River populations and from the eggs of those fish. The starlet broodstock population is increased every year with up to 10 percent of new adult fish and up to 10 percent of imported fry (5-10 g). Since 2010, in the process of broodstock formation, a line of sperm was stored in liquid nitrogen. It also amounted to 10 percent. The scheme of sterlet broodstock formation is shown in Figure 6. We have formed lines of broodstock and now can make forecasts of estimated spawning dates. The structure of different sturgeon species broodstock populations was formed to avoid inbreeding. Therefore, groups with different origins were formed. They were imported from different areas of southern Russia (Astrakhan, Volgograd and Rostov regions). Spawning interval decreases with age. Sterlet from the Volga River have the shortest spawning interval (5.5-6.0 months; Table 1). Specialists of SSC RAS have developed a software program for sturgeon broodstock registration that allows creation of a database that includes information on individual biological, biometric, physiological and reproductive parameters of all tagged fish that are maintained as broodstock. In this database program, information about species and population of each individual, age, date of importation from other hatcheries and tank number is shown. There is also the opportunity to trace individual fish growth. To accommodate the rapid selection of tagged individuals, the search string capability is provided. In the process of ultrasonic scanning, the sex and stage of sexual maturity (I–V) are recorded in the program. During the spawning season, the date of each spawn and the quantity and quality of obtained eggs of sturgeon breeders is recorded. The program allows tracing of the physiological state of individual broodstock on the basis of the following hematological parameters: • hemoglobin concentration • erythrocyte sedimentation rate • hematocrit value General Information/ Renseignements généraux Conference coordinator Joanne Burry Tel : 709-437-7203 Email : jmburry@nl.rogers.com www.aquacultureassociation.ca OM Farming our waters - Agrifood Innovations Cultiver nos eaux : Innovation en agroalimentaire Co-Hosts / Hôtes conjoints (CONTINUED ON PAGE 58)
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