Rybohospodars'ka nauka Ukrayiny (Fisheries Science of Ukraine)

23-36

Authors: P. Shekk, Yu. Astafurov

Purpose. To study reproductive characteristics of female freshwater shrimp M. nipponense (Dniester population) in natural and artificial conditions. Methodology. Field studies were carried out from April to October 2016-2019 in the Kuchurgan and Dniester lagoons, fish ponds and lakes of the lower Dniester and Turunchuk rivers. Shrimp were caught in coastal areas with net and special traps using a bait (ground silverside). The studies were conducted in the field and laboratory conditions. For experimental work, the caught shrimp was transported to the aquarium department of aquatic biological resources and aquaculture of Odessa State Ecological University. For the cultivation and reproduction of shrimp, 0.3 m³ glass aquariums were used, combined in an experimental setup with a recirculating aquaculture system (RAS) with a total working volume of 1.2 m³. During the experiment, the conditions were close to the environment, where shrimp were caught. During the biological analysis of the shrimp, following parameters were determined: sex, total length and body weight (stage and duration of embryogenesis). The survival of M. nipponense under various conditions was also recorded. Following modern instruments were used for the express analysis of hydrochemical parameters of the environment: ECOTEST -2000 T (О2; NO-2; NO-3; NH-4; CO2; phosphates, pH), Azha-101M thermooximeter (Т, оС; О2), pH meter-150 m); ATAGO-100 refractometer (salinity and water density). Saline solution, in special experiments, was produced in laboratory conditions by diluting seawater. Findings. Fertilized shrimp eggs have an oval shape, and their average sizes varied within 0.58-0.66 mm (length) and 0.39-0.46 mm (width). It was found that the size of fertilized eggs in M. nipponense of the Dniester population differed in size in various natural waters. The largest sizes (0.66 ± 0.035 and 0.46 ± 0.014 mm) and an average volume of 0.073 mm3 were observed in shrimp eggs from the Kuchurgan estuary. These parameters significantly (P≥0.95) differed from shrimps from the Dniester estuary, which had the smallest sizes (0.58 ± 0.022 and 0.39 ± 0.011 mm) and average volume (0.046 mm3). Shrimp from ponds and lakes of the Dniester and Turunchuk had average size and egg volume, which, according to these parameters, did not significantly differ from those of individuals from the Kuchurgan and Dniester estuaries. An analysis of shrimp fertility of the Dniester population showed that the IRF and FRF increase in direct proportion to the increase in the size and weight of females that is natural for all poikilothermic animals. IRF in the linear size range of female M. nipponense from the Dniester population of 2.5-7.9 cm and weight of 2.2-7.3 g increases from 3441 ± 942 to 10241 ± 1323 eggs in one clutch. The duration of embryogenesis and survival of shrimp embryos with an increase in water temperature from 18 to 31 ° C is reduced from 42 to 20 days. The optimum is at a temperature of 27 ° C, which ensures the survival of 98% of the embryos. Shrimp M. nipponense can reproduce at a salinity from 0 to 9‰, but the optimum salinity is 5‰ which in the range of optimal temperatures ensures the survival of 98% of embryos with a minimum duration of embryogenesis. Originality. The reproductive characteristics of female M. nipponense from the Dniester population were studied for the first time. It was shown that the fertilized shrimp eggs of the Dniester population differ in size in different areas of the lower reaches. The dependence of the initial (IRF) and final (FRF) realized fertility on the mass of shrimp was found. The duration of embryogenesis and the survival rate of embryos were studied depending on the temperature and water salinity. The optimal temperature and salinity parameters for embryogenesis of M. nipponense of the Dniester population have been established. Practical value. The research results made it possible to give an objective characterization and assessment of the fertility of the introduced species M. nipponense in the conditions of the Lower Dniester basin and can be used to develop technology for its artificial reproduction.

58-73

Authors: I. Buzevich, A.Mruk, A. Kucheruk

Рurpose. To develop scientific bases for reproduction of European grayling populations by the Carpathian River basin in artificial and natural conditions. Method ology. Fishery volumes were determined on the basis of indicators of development of the natural forage base of river systems. Actual weight gains in the younger age groups and estimated mortality rates. Natural mortality coefficients were calculated from the parameters of the Bertalanffy equation, which was determined on the basis of the actual size and age parameters of the grayling. Survival of seagrasses was determined on the basis of the calculated coefficient of natural mortality in the first year of life and the ratio of survival of different age groups, which for larvae and seagulls weighing 5 g was 3.7. Findings. The analysis of the available data shows the fundamental possibility of introducing a viable European grayling youth to replenish the reproductive nucleus of the natural population, which in turn will create objective prerequisites for population growth and create prospects for viewing the conservation status. The parameters of the Bertalanffy equation, calculated on the average size and age parameters of the grayling of the Transcarpathian rivers, were: K (year-1) - 0.297; L∞ (cm) - 36.9; t0 (year) - 0.168. natural mortality, differentiated by age, and, accordingly, annual mortality rates. On the basis of this, the indicators of instantaneous natural mortality, differentiated by age, and, accordingly, indicators of annual mortality were determined. The potential accumulation of grayling ichthyomas can be determined on the basis of the total annual mortality and the actual weighting by size classes. The baseline stocking index can be used as a baseline weighted area (based on area). Yew, which is 418.6 copies. / ha of annuals. The bioproductive potential of the rivers of the Carpathian region allows to increase fish productivity on the European grayling by an average of 8.6-21.2 kg / ha. For this purpose, during the four-year period, it is necessary to fish the Tisza River basin with a grayling of at least 5 g with a total amount of 620.5 thousand. Ex. per year. and the Prut River Basin - 122,000 copies. per year. Originality. Methodical approaches for determining quantitative indicators of grayling activities are substantiated. Practical value. The practical implementation of the obtained results will be carried out during the reproduction and cultivation of viable planting material, regulation of quantitative and qualitative indicators of fishing.

87-94

Authors: V. Gurbik, Yu. Glushko, I. Hrytsyniak, N. Tushnitskaya

Purpose. To analyze age and seasonal dynamics of the cytogenetic parameters in different age groups of Halych carp under conditions of industrial cultivation. Methodology. Blood sampling for smear preparation was performed from the caudal vein. The smears were preserved in methyl alcohol and stained using the Romanowsky-Giemsa solution. Further analysis was performed under a Primo Star Zeiss microscope at 1000x magnification. The erythrocyte frequency from the micronucleus, single-nucleus lymphocytes from the micronucleus, dual-nucleus lymphocytes, and apoptosis were counted in the smears. The data obtained was measured in ppm (‰). Findings. Erythrocytes with micronuclei in different age groups of the Halych carp ranged from up to 2.7 ‰ ± 0.4 - 4.0 ‰ ± 0.7. The number of lymphocytes with micronuclei was 2.0 ‰ ± 0.4 - 2.4 ‰ ± 0.2. Dual-nucleus lymphocytes in the Halych carp ranged from 2.0 ‰ ± 0.2 to 2.7 ‰ ± 0.3. As a result of cytogenetic analysis, a 11% decrease in the level of cells with apoptosis in age-3 Halych carp compared to young-of0the-year was detected. After wintering, erythrocytes with micronuclei in age-1 and age-2 carp were recorded to be within 2.7 ‰ ± 0.5 - 3.1 ‰ ± 0.6. The incidence of lymphocytes with micronuclei in the Halych carp decreases, while this parameter in age-2 fish decreased by 8% and amounted to 2.4 ‰ ± 0.2. Dual-nucleus lymphocytes in the Halych carp after wintering ranged from 2.9 ‰ ± 0.1 to 3.3 ‰ ± 0.2. As a result of a comparative analysis of cytogenetic parameters of age-1 and age-2 carp, a significant difference in the number of lymphocytes with dual nuclei was found (P ‹0.01; ts = 3.57). The results of the studies show that an increase in this parameter was triggered by rapid growth of fish seeds in pond conditions. Originality. For the first time, the variability of the cytogenetic apparatus of different age groups of the Halych carp at different stages of the technological process in industrial cultivation was analyzed. Practical value. The results obtained can be used for further breeding work with the Halych carp in the region.

109-122

Authors: M. Korуlyak

Purpose. The purpose of the study was to investigate the feasibility and efficiency of the use of milk thistle in the process of commercial cultivation of the common carp in terms of productive and economic indicators. Methodology. The study was conducted in two experimental and control ponds, which were stocked with carp yearlings at a density of 1000 ind./ha. The carp of the first experimental group during the growing season were additionally fed with a diet containing 1% of milk thistle, while the second experimental group – 5%. During the work, optimal conditions of carp cultivation were maintained. The dissolved oxygen, temperature hydro-chemical and hydro-biological regimes of the aquatic environment were monitored and the efficiency of cultivation at the end of the growing season was analyzed by conventional methods. Findings. In general, the conditions of fish cultivation in the experimental and control ponds were satisfactory. No relationship was observed between the hydro-chemical regime of the experimental ponds and the diet composition. The average seasonal biomass of feed organisms of zooplankton and zoobenthos during the growing season were 4.22 – 5.11 g/m3 and 1.37 – 1.62 g/m2 respectively, and equally contributed to the process of carp cultivation both in experimental variants and in the control. It was found that the average weight of carps fed with diets contained 1% and 5% of ground milk thistle was higher by 7.3% and 5.6%, respectively, fish productivity – by 9.8% and 7.2%. At the same time feed costs per kilogram of production decreased by 5.9% and 8.8% compared to the control. The cost of additionally obtained fishery products when supplementing the diet with 1% of milk thistle amounted to 11849 UAH/ha, 5% – 10217 UAH/ha. The attributable profit, including costs of feed and fish seeds, when using 1% of milk thistle was 13.1% higher than in the control, 5% – 0.7% higher in the control group. Scientific novelty. According to a wide range of biologically active properties of milk thistle, the effect of this additive on the productive and economic indicators in the process of age-2 carp has been studied for the first time. The implementation of this practice provided an opportunity to increase fish productivity by feeding fish with artificial feeds of improved composition. Practical value. Reducing the cost and obtaining additional weight gains during the cultivation of aquaculture products can be ensured by improving the quality characteristics of fish feeds, and, accordingly, the physiological parameters of age-2 carp organism.