Purpose. The determination and analysis of main biological characteristics of silver bream from the point of view of the formation and exploitation of its commercial stock in the Kyiv reservoir.
Methodology. The work is based the results of monitoring field studies carried out on the Kyiv reservoir during 2012–2014. Ichthyological materials were collected from standard commercial gill nets with mesh sizes of 30–80 mm, which were set in different habitats and depths of the reservoir. Collection and processing of samples was carried out using conventional ichthyological methods adapted for the Dnieper reservoirs.
Findings. According to the data of monitoring gill nets, silver bream population in 2014 was composed of 10 age groups. The majority of their population (70.8%) in catches was composed of age-5 to age-7 fish, i.e. the number of modal classes increased due to the right wing of the older age groups. The frequency distribution of silver bream had a shape of a curve with wide, however broken (due to the reduction in age-5 fish) peak and gradual decrease. Age-length properties, fatness parameters and condition factor of silver bream in the Kiev reservoir during last years remained on the stable high level indicating on favorable fattening conditions and forming the ichthyomass of this species.
At the present time, silver bream of the Kyiv reservoir formed a commercial stock with such qualitative and quantitative characteristics, which allow exploiting it in the mode of traditional commercial harvest and specialized harvest of silver bream concentrations with the use of gill nets with mesh sizes of 50, 60 mm.
Originality. We obtained and analyzed the new data on the current state of silver bream (Blіcca bjoerkna) in Kyiv reservoir as an important element of commercial fish production.
Practical Value. The results of the work allows increasing qualitative and quantitative characteristics of silver bream catches and will be used for the preparation of commercial fishery regime for the Kyiv reservoir.
Purpose. To investigate the effect of the bacterial preparation "Komplezim", which is recommended for the prevention of mass reproduction of blue-green algae through algocoenosis correction, water cleaning and sanitary regime restoration, for the biological balance and self-purification of natural and farmed fish ponds of all sizes exposed to artificial or natural pollution.
Methodology. The studies were carried out during 30 days in a 0.01 hectare pond with a depth of 1.0–1.5 m. The doses of the bacterial preparation "Komplezim" in the form of a solution were applied over the water surface of the experimental pond. The conventional techniques of hydrochemistry and hydrobiology were used to perform hydroecological studies.
Findings. The study results showed that after the exposure of the bacterial preparation "Komplezim", pH level of water and oxidation rates were within the acceptable limits. Permanganate and dichromate oxidation decreased in the same manner in the middle and end of the experiment compared to initial values. Calcium, magnesium, and sulfate levels were lower compared to control values. This effect can be explained by the fact that bacteria from the “Komplezim” composition in aquatic medium started intensive metabolizing the products of organic decomposition enriched in calcium, magnesium and sulfates. The consequence of the application of "Komplezim" was an increase in the concentration of organic chlorides simultaneously with nitrites. The obtained results indicate that bacteria strains included in the “Komplezim” composition inhibit the processes of cyanobacteria reproduction by algocenosis correction and contributes to the optimization of hydrochemical conditions for pond fish rearing.
Originality. The effect of the bacterial preparation "Komplezim" on the reproduction of blue-green algae and hydro-chemical composition of the water has been investigated for the first time.
Practical value. Application of the bacterial preparation "Komplezim" results in the balanced development of blue-green bacteria, which are developed in large amounts in intact water bodies that largely resolves operational and environmental problems and allows achieving accelerated processes of the purification of water bodies.
Purpose. Analysis of the dynamics of structural parameters as an integral property of the processes of recruitment and elimination of the reproductive and commercial population nuclei of pikeperch of the Kyiv reservoir.
Methodology. Ichthyological material was collected during spring-summer period of 2015-2016 from survey catches done with gill nets with mesh sizes of 30-120 mm. Collection and processing of the field materials were carried out using conventional methods. In total, catches of 3.5 thousand net-days were processed during the study period and 1031 individual pikeperch were analyzed. Total mortality coefficient (Z) was determined by graphic method based on the dynamics of the natural logarithms of the abundances of different age groups. Statistical processing of data was done in MS Excel.
Findings. Commercial landings of pikeperch during last 10 years has a clear trend for a growth: from 20-25 to 80-100 tons. The catch of pikeperch per unit effort of survey gill nets in an interannual aspect is also characterized by a growth. At the same time, there is a certain improvement of the structural parameters of pikeperch population, e.g. an increase in the maximum age and extension of the modal frequency distribution. Age-3 and age-4 fish represented the major part of the population (71.6%) in the catches of 2015, while the share of age-5-6 fish was also relatively high (10.8%). It resulted in an increase in the weighed mean age of the pikeperch population to 4.5 years. For 2016, there is a significant shift of the frequency distribution to its left wing – the major part of the population (64.7%) was composed of age-2 to age-4 fish. The weighed mean age in 2016 decreased to 2.6 years that was due first of all to abundant recruitment and intensive elimination of middle age groups. Total mortality (Z) of pikeperch in 2015-2016 was 0.53-0.56 that corresponded to normal conditions of the formation of the commercial stock of this species and moderate level of its exploitation.
The major part of pikeperch catches in 2016, both by number (61.5% of the total catch) and biomass (54.9%) was done by gill nets of 40-60 mm mesh size (in 2015 – a=60-70 mm). The distribution of pikeperch catches according to the mesh sizes indicate on the necessity for the implementation of a special regime for the exploitation of this species.
Originality. We obtained new data for the theoretical justification of the principles of the maintenance of optimum structural parameters of pikeperch population in the condition of a commercially fished water body.
Practical value. The study results will be used for the preparation of the procedure of the fisheries exploitation of ichthyofauna in the Kyiv reservoir, which include, in particular, the regulation of mesh sizes in commercial fishing gears.
Purpose. The determination of a maximum annual amount of fish reared in cagesm which does not result in the deterioration of the ecological state of water cooling ponds of the Zmiev Thermal Power Plant and Kursk Nuclear Power Plant series Ι and ΙΙ.
Methodology. The specific (per 1 ton of farmed fish) nutrient intake necessary for calculations was determined according to the data of own studies. For this purpose, we perfrormed the determination of the input of suspended solids into cooling ponds from cage lines. The calculation of mean fish weight increase during the period of trap exposition bsed on fish farm data allowed calculating the specific input of suspended solids from cages. The effect of artificial feeds and a mixture of feed resideus and fish of fishes collected under cages on water quality were evaluated in the condoitins of laboratory experiments. The effect of fish metabolites on water quality was taken into account according to literature data.
Findings. In the specific conditions of the investigated cooling ponds, the environmentally allowable concentrations of biogenic elements are established based on the mineral nitrogen content. With the mean volume of the Zmiev Thermal Power Plant of 40.5 million m3, the total amount of mineral nitrogen, which can be introduced with cage aquaculture residues, is 21.87 tons. When rearing one ton of fish in cages, 91.3 kg of mineral nitrogen get into the cooling pond. Thus, the environmental capacity of the Zmiev Thermal Power Plant cooling pond for cage fish farming is 281.7 tons. Accordingly, the allowable amounts of the production of cage fish farming for the Kursk NPP taking into account N content of 0.406 mgN/dm3 and volume of the cooling pond is 625.5 tons.
Originality. For the first time, we calculated the ecological capacity of cooling ponds of the Zmiev TPP and Kursk NPP, series I–II.
Practical value. Application of the results presented in the paper will allow creating and developing cage fish farms without disturbing the ecological state of cooling ponds of power plant, on the base of which they are created.
Purpose. To establish and assess acute toxicity parameters of "ROST-concentrate (10+7+7)" acute toxicity for planktonic crustacean Daphnia magna Straus and carp fingerlings Cyprinus carpio L.
Methodology."ROST-concentrate (10+7+7)" contains macronutrients (nitrogen, phosphorus, potassium), which are valuable for the pond ecosystem, and trace elements in environmentally safe chelate form.
We determined the vital (LC0), absolutely lethal (LC100) and median (LC50) drug concentrations on the test organisms such as crustacean D. magna (Cladocera) and carp fingerlings C. carpio. The determination of acute lethal toxicity on D. magna was conducted according to DSTU 4173: 2003 that corresponded to the international standard ISO 6341: 2012, MOD . The temperature of the experiment was 20±0.5 oC. The exposure time - 96 hours. Daphnia were not fed. Following "ROST-concentrate (10+7+7)" concentrations were tested: 100; 75; 50; 25; 10; 1; 0.5; 0.1; 0.05; 0.01; 0,005; 0,001 ml/dm3.
We also determined the acute lethal toxicity on carp fingerings with an average weight of 6.78±0.63 grams following the standardized procedure . Pond water was used in the experiment. Ten fish were placed into a 40 L aquarium. Following concentrations of "ROST-concentrate (10+7+7)" were investigated: 0,5; 1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 15; 20; 30; 40 mg/L. The exposure time was 24 hours. Water temperature was 19±1oC. LC50 drug median concentration was calculated according to G. Kerber method.
Findings. The parameters of integral acute toxicity of "ROST-concentrate (10+7+7)" on typical organisms of fish pond ecosystems.With 96 h exposure on juvenile cladoceran D. magna, lethal concentration was LC100 = 5,00 ml/dm3, median concentration was LC50 = 0,15 ml/dm3, vital concentration was LC0 = 0,01 ml/dm3. According to the classification of toxic substances, the "ROST-concentrate (10+7+7)" is characterized by low toxicity on juvenile cladoceran D. magna. With 24 h exposure on carp fingerling: lethal concentration was LC100 = 40,0 ml/dm3, median concentration was LC50 = 18,6 ml/dm3, vital concentration was LC0 = 7,0 ml/dm3. According to the classification of toxic substances , "ROST-concentrate (10+7+7)" was practically nontoxic to 6.78 ± 0.63 g carp juveniles.
Originality. First study of the acute effect of organic-mineral preparation "ROST-concentrate (10+7+7)" on planktonic cladoceran D. magna and carp juvenile C. carpio.
Practical value. The obtained results show a very low level of toxicity of the drug and safety for organisms of fish-breeding pond ecosystem organisms after its application.
Purpose. To assess the current state of the Pontic shed in the Dniester estuary.
Methodology. Ichthyological samples has been collected in the Dniester estuary according to standard methods. Fish has been caught using gill nets with 30–32 mm mesh size. The methodical guidelines "Metodiki zboru і obrobki іhtіologіchnih і gіdrobіologіchnih materіalіv z metoju viznachennja lіmіtіv promislovogo viluchennja rib z velikih vodoshovishh і limanіv Ukrayiny" (Кyiv, 1998) and "Metodicheskie ukazanija po ocenke chislennosti ryb v presnovodnyh vodoemah" (Moskva, 1990) were used for fish stock assessment. The dynamics of water discharge in the Dniester River was presented based on the observations at gauging stations in Bendery and Tiraspol.
Findings. The data of catch dynamics, age and sex composition, length-weight characteristics of the Pontic shed Alosa immaculata Bennett, 1835 in the Dniester estuary 1994–2016 have been presented in the paper. According to official statistics data, the annual catch of the Pontic shed in the Dniester River and Dniester estuary in 1996–2016 ranged from 1.3 to 62.0 tons, with an average of 24.6 tons — 9.8% of the total catch of the Pontic shed in the Danube-Dniester interfluves.
A dependence of catch amounts on the water regime of the Dniester River has been observed. An increase in the water flow rate in the river during the spring flood in full-flowing years (annual flow of more than 10 km3), contributes to an increase in the Pontic shed catch in the Dniester estuary. Currently, catches are dominated by age-3 (40.5–59.2% of the total catch) and age-4 (30.7–42.0%) fish. Older age groups are not numerous. Sex ratio was unequal. Females predominated in the control catches, accounting for 65.4% of the total catch. The stock of the Pontic shed entering the Dniester estuary in 2016 was estimated to be 221.0 tones. We recommended to extend the ban of the specialized Pontic shed fishing during the spawning period.
Originality. The current state of the spawning stock of the Pontic shed population in the Dniester estuary is presented.
Practical value. It is recommended to change the timing of the ban on the specialized Pontic shed fishing in the Dniester estuary, to ensure the passage of a greater number of individuals to the spawning grounds.
Purpose. To analyze basic biological characteristics of the commercial stock of rudd. Scardinius erythrophthalmus (Linnaeus, 1758) of the Dnieper-Bug estuary system in the conditions of the regulated flow of the Dnieper River.
Methodology. Morphological peculiarities were determined based on the analysis of meristic and plastic features. When assessing the biological state of the commercial stock rudd, the main attention was given to the age, sex structure, fecundity, characteristics of length-weight growth and condition factor. The ichthyological material was collected during the work of monitoring stations of the Institute of Fisheries NAAS of Ukraine, the operation of which was regulated by protocol decisions of the Scientific and Commercial Council of the State Agency of Fisheries. Field and laboratory processing of collected data was carried out using conventional ichthyological methods and guidelines.
Findings. The analysis of meristic features of rudd of the Dnieper-Bug estuary system showed that fin formulas were as follow: D – III 7-9 (10) (М=8.19±0.14); A - III 10-12 (М=10.81±0.17); P - I (12) 13-15 (16) (М=14.26±0.18); V - II 7-8 (М=7.78±0.08). The lateral line had from 38 to 47 scales (М=42.63±0.65). 7-8 (М=7.67±0.09) transverse rows of scales were located above lateral line, while 5-6 (М=5.6±0.9) under it. A peculiarity of the current biological state of rudd stock is stable age structure with the domination of young age groups. An increase in the ratio of the maximum age groups against the background of an insignificant trend for the decrease of the ratio of age-5 fish indicates on an increased pressure (both commercial and recreational) on rudd recruitment. A confirmation of it is an increase of the mean weighed age of the commercial stock from 4.16-4.17 to 4.26-4.31 years. The sex structure is typical for cyprinids. A trend of the domination of males in younger age groups and females in older age groups is observed. In total, sex ratio was practically equal (1:0.96) but with insignificant predominance of females. The length-weight growth rate is intensive enough. The most variable growth features were observed in age-4 fish that was related to sexual maturation. The absolute individual fecundity varied from 11.02±0.26 thousand eggs in age-3 fish to 132.56±1.48 thousand eggs in age-7 fish. At the same time, the variability (Cv) gradually decreased from 5.27% to 2.50%, respectively, in the indicated age groups. The condition factor of rudd is satisfactory. Depending on the age, it varied from 2.27±0.02 to 2.58±0.03 with Cv=1.46-2.49%.
Originality. The data of the morphological structure of the rudd of the Dnieper basin have been significantly improved, especially in the lower reach in the conditions of the transformed flow. The existing information on the age, sexual structure, fecundity and length-weight growth has been supplemented.
Practical value. Current data obtained during the study have to become a scientific justification of the optimization of commercial pressure on native fish fauna of the Dnieper-Bug estuary system that becomes important in the aspect of nature protection measures aimed at preserving biodiversity of the transformed water bodies of Ukraine.
Purpose. To study food resources, feeding conditions and trophic relationships of the brown trout (Salmo trutta morpha fario), rainbow trout (Oncorhynchus mykiss), and European grayling (Thymallus thymallus) in a Transcarpatioan river.
Methodology. The material on the food resources and feeding of the brown trout, rainbow trout, and European grayling was collected in summer period of 2012 on the Shypit river. The study was performed on two different sites of the river: the first one was located on the middle pre-mountain reach of the river (upstream of the Hydroelectric power plant), the second one – on the mountain reach of the river (near tourist base) on typical biotopes: I – with boulders and riffles with fast current; II – with medium size stones and low riffles with moderate current; III – with small stones, sand and slow current. The material was collected and processed according to standard and unified hydrological, ichthyological, and trophological methods.
Findings. We studied the level of macrozoobenthos development and obtained data on feeding and trophic relationships among brown trout, rainbow trout, and European grayling on different biotopes on pre-mountain and mountain reaches of the Shypit river. The number of “soft” macrozoobenthos on different biotopes varied from 972 to 2576 ind./m2 with biomasses from 6.3 to 121.8 g/m2. Total diet overlap index (DOI) between brown trout and rainbow trout on the biotope with boulders and fast current in the pre-mountain reach was 32.4% by number and 20.3% by biomass, while that on the mountain reach was 49.6% and 52.9%, respectively. On the biotope with medium size stones and moderate current, the diet overlap index between rainbow trout and European grayling in the pre-mountain reach was 19.0% by number and 27.9% by biomass.
Originality. First study of the diet and tropic relationships of the brown trout, rainbow trout, and еuropean grayling on different reached of the Shypit river.
Practical value. The results of this work can be used when calculating the amounts of brown trout, rainbow trout, and European grayling to be stocked into rivers of the Transcarpathian region.
Purpose. The analysis and evaluation of wintering of galician carp fingerlings in pond conditions of Subcarpathia
Methodology. Study was conducted at the farm "Corop", located in Rawa-Ruska, Lviv region. The objects of research were fingerlings of Galician carp, growing under semi-intensive conditions. The main fish-breeding and biological indexes were examined during the autumn catches and after spring inventory using conventional fish farming methods. Determination of the biochemical composition of skeletal muscles was conducted under zootechnical analysis.
Findings. The weight of fingerlings of Galician carp during the wintering in ponds of fish-farm "Carp" was an average 104±7,5 g, nutritional ratio was at 3.1±0,3 while after the following winter it was 2.6±0,3. The biochemical composition of muscles in Galician carp was within legal parameters, confirming satisfactory physiological state of fish before winter maintenance.
Environmental conditions of winter incubation of fish corresponded to fish breeding requirements. Thermal regime of pond during the winter of Galician carp age 0+ was in the range 1°C–6°C. The quantity of dissolved oxygen also does not exceed the critical limits. Оther hydro-chemical parameters also correspond to the fisheries requirements.
After inventory of wintering ponds the average weight of catched fingerlings was 92±7,7 g. The out of fish wintering was within 86%. The absolute weight loss at the end of the winter period was not exceeded 12 g, consequently the relative ratio was 11.5%.
From the obtained data, it could be concluded that the process of the wintering of Galician carp fingerlings, was carried with minimal losses for industrial breeding in general.
Originality. For the first time the Galician carp fingerlings were assessed for wintering in ponds of Subcarpathia.
Practical value. The results of current research will be used in planning and industrial breeding of Galician carp.
Purpose. The study of the osmotic sensitivity of pike (Esox lucius, L., 1758) spermatozoa.
Methodology. The osmotic response of pike spermatozoa was investigated by spectrophotometry method based on the kinetics of light transmission of cells suspensions, which were placed in distilled water and 10–200 mOsm/kg solutions of NaCl .
Measurements of light transmittance were carried out using photoelectrocolorimeter KF-77 (ZALIMP, Poland), equipped with a magnetic stirrer and thermostatted sample compartment. The coefficient of permeability of spermatozoa plasma membrane for water molecules (Lp) was determine by approximation of the experimental time dependences of the relative volume by solutions of the equations of modified Kedem-Kachalskyi physical-mathematical model of transmembrane mass transport. The activation energy (Еа) of the substances transfer across the cell membrane was calculated taking into account lnLp(1/T) dependencies.
Findings. The characteristic time of water penetration is about 40-50s within 100-200 mOsm/kg range (12 °C). Membrane permeability coefficient of pike spermatozoa for water molecules is 5.43 - 1.15 - 10-15 m3/Ns. The decline in coefficient of membrane permeability for water molecules in the range of 25–10 °C is characterized by the activation energy of water transfer, which is 64±5 kJ/mol, that indicates about water molecules penetration into spermatozoa via a passive diffusion through the lipid bilayer. Hypoosmotic resistance of pike spermatozoa, estimated as time before lysis of 50% cells incubated in distilled water, is 70–110 s (12 °C).
Developed approaches also can be used as simple and quick tests of the functional state of cell membranes.
Originality. The coefficient of plasma membranes permeability of pike spermatozoa and its temperature dependence were defined for the first time.
Practical value. The results are used in the design of media and modes of pike sperm cryopreservation.
Purpose. Study of the genetic structure specificity, intra- and interpopulation genetic variation of the brood stocks of Ukrainian scaled carp from different fish farms of Ukraine using DNA markers (ISSR-PCR).
Methodology. A PCR (ISSR-PCR) method with appropriately selected primers has been used to investigate the genetic structure specificity.
Findings. The genetic structure analysis of Ukrainian scaled carp has been carried out using three microsatellite DNA loci: (AGC)6G, (AСC)6G, (AGC)6С. In total, 55 amplicons were detected for all primers. Fifteen primers were detected when using (AGC)6G primer, 17 for (AСC)6G primer and 23 for (AGC)6С primer. The molecular weight on electropherograms had maximum values when using (AСC)6G primer (500 n.p. – 3500 n.p.) in Nyvky carp. The detected specific differences between the examined populations of scaled carp depend on their genetic origin. Variations of the detected amplicons are sufficient for separating individual fish or, if works are carried out with a group of broodfish, for selecting parental pairs for increasing genetic diversity.
Originality. The use of ISSR-markers allowed detecting the peculiarities of the genetic structure, level of genetic variability of the brood stocks of Ukrainian scaled carp.
For the first time, we obtained new data on the specificity of the genetic structure when using PCR techniques, which allow detecting specific mechanisms of the maintenance of the relative stability of the genetic material of Ukrainian scaled carps and allow controlling and preserving the specificity of their genetic structure.
Practical value. Proposition of a method for the genetic control of Ukrainian scaled carp stocks based on the application of PCR techniques, which allows performing an analysis of the genetic structure of fish stocks and using the genetic information at early stages of breeding selection process.
Purpose. Determination of the peculiarities of intraspecific genetic polymorphism of Russian sturgeon based on microsatellite DNA markers.
Methodology. The polymerase chain reaction (PCR) with the detection of results based on capillary electrophoresis was used for the determination of intraspecific polymorphism of microsatellite DNA Russian sturgeon.
Findings. On microsatellite DNA markers was investigated genetic polymorphism of Russian sturgeon (Acipenser gueldenstaedtii Brandt) Black Sea and Dnieper population. It was identified of 56 allelic variants of such DNA-markers investigated as LS-19, LS-68, LS-39, Aox-27, LS-54 and Aox-45. On locus LS-19 allelic variants have been identified, the locus LS-68 was the most polymorphic and consisted of 21 alleles, 11 allelic variants have been identified by the LS-39 locus, and 16 allelic variants have been identified for the LS-54 locus. Aox-27 locus was the least polymorphic microsatellite markers among the study and consisted of 7 allelic variants. For Aox-45 locus 16 allelic variants have been identified. A study of the genetic structure of the Russian Black Sea-Dnieper sturgeon population is not currently been carried out in full and reduced only to the evaluation of the number of identified allelic variants and relative frequency of alleles. Calculations of heterozygosity parameters for Russian sturgeon became complicated definition tetraploid genetic structure of this species on the studied DNA markers. Such studies are an important component in the further work on the conservation of genetic diversity of sturgeon, which will provide an opportunity to carry out the state control over reproduction and preservation of valuable and endangered species under increased anthropogenic impact on natural populations.
Originality. For the first time, new data of the peculiarities of the intraspecific genetic polymorphism of Russian sturgeon was obtained using species-specific microsatellite DNA markers.
Practical value. The data obtained can be used to control the genetic processes in the populations of Russian sturgeon, as well as to develop a complex of measures to improve the efficiency of breeding and conservation of the structure and species diversity of this sturgeon species.
Purpose. To anayze scientific sources on physiological-biochemical pecularities of reducing-oxidizing processes, including peroxide oxidation of lipids and work of the system of antioxidant protection system in sturgeon species (Acipenseridae). The initiation and process of the oxidative stress have been described. The main products of peroxide oxidation of lipids, antioxidants of natural and artificial origin, organs and tissues for the studies of reducing-oxidizing processes have been examined.
Findings. The work generalizes the processes of lipid peroxidation. Briefly outlined the main mechanism of action of antioxidant enzymes. Antioxidant defense system plays one of key role in the life of organism due regulating its series of metabolic processes, use of assessing of its state gives an opportunity obtain quantitative information on the progress of these processes. The products of free radical peroxidation (dien conjugates and malonic dialdehyde) can also act as a sort of biomarkers of tissue damage, because their content can judge about the intensity of the flow of free radical processes in the various systems in organism. The review contains a description of the peculiarities of the liver and its involvement in lipid metabolism and antioxidant defense system. It is shown the most common antioxidants used in the feeding of sturgeon. Organs and tissues, which should be used for studying the processes of peroxide oxidation of lipids in sturgeon species, have been examined.
Practical value. The systematized data regarding peroxide oxidation of lipids, oxidative stress and antioxidant protection system allow finding a balance between these processes. The data on antioxidants, which are used in feeds for sturgeon species, will be useful for sturgeon culturists. The array of the generalized information will be important for scientists who study the pecularities of the processes of peroxide oxidation of lipids and antioxidant protection system in sturgeon species.