Purpose. Establishing the ecological potential of water bodies of various types in the composition of small rivers of urbanized territories based on their ichthyocenosis structure features, hydrochemical and toxicological indices.
Methodology. The objects of the study were ichthyofauna species as well as water and bottom sediments. Materials were collected during 2015-2016 on the sections of the Gorenka, Lybid, Nyvka and Syrets rivers within the city of Kyiv. Collection of ichthyological material was carried out with a hand net, without the use of tools and methods that are in conflict with the law or need special permission. Processing of samples was carried out in accordance with generally accepted methods.
Findings. It has been shown that the qualitative composition of ichthycenoses of small rivers depends on their hydromorphological and hydrological characteristics. According to the ichthyotcenoses structure, the highest ecological potential was inherent to waterbodies, where the connection with the receiving reservoir was maintained. The dominant complex in the ichthyotcenoses of such water bodies were native fish species indifferent to water flow velocity, which perform seasonal migrations, whereas mainly short-cycle limnophilic species including invasive ones were presented in isolated hydrostructures of water bodies. The water quality assessment based on hydrochemical and toxicological indicators also revealed the effect of the anthropogenic transformation of water bodies on their ecological potential. Thus, higher contamination and degree of water toxicity were inherent to more transformed watercourses.
Originality. It has been established that in the case of small rivers within the boundaries of Kyiv, ecological potential of water bodies based on their ichthyofauna structure depended more on the preservation of their connectivity with the receiving reservoir and water flow rate than on hydrochemical and toxicological characteristics.
Practical value. The study results can be used to develop measures aimed at preserving and restoring small river ecosystems, in particular their ichthyocenoses.
Purpose. The development of a Fish Yield Prediction Model for lakes and water reservoirs of the Kyrgyz Republic based on easily measured physico-chemical and biological indicators (limnological parameters) for the effective management and sustainable use of fish resources.
Methodology. Water samples for the analysis were taken once at each season (winter, spring, summer, autumn) during 2014 - 2015. The sampling included the collection of the following parameters: water temperature, acid-base balance of water (pH), electrical conductivity, dissolved oxygen, total dissolved solids (TDS), total alkalinity, nitrates, chlorophyll a. The samples were taken in surface layer of water at a depth of 0.5 m into 250 ml sterile chemical bottles. Chlorophyll "a" concentration was measured by a spectrophotometric method in laboratory conditions, according to a method described by Stirling H.P. The total alkalinity was determined by titration of sodium tetraborate solution (reverse titration), nitrates were determined by a photometric method with the Griss reagent after reduction in the cadmium reducing agent. The measurement of rapidly changing parameters, such as dissolved oxygen concentration (О2) was carried out by portable field equipment “OAKTON” DO 110, acid-base balance (pH) – “OAKTON” PH 11, measurement of water temperature, electrical conductivity, total dissolved solids (TDS) was carried out with the device "Orion Star"A 322. All measurements were taken directly in water areas.
Findings. According to data analysis, a number of indices, such as the morpho-edaphic index (MEI), primary productivity and biomass of phytoplankton, are strong indicators of fish yield, both in temperate and tropical lakes and reservoirs. It was identified that with an increase in the morpho-edaphic index, fish yield per unit area increases. Based on the results of our analysis, a Fish yield prediction model in six water bodies of the Kyrgyz Republic was developed, which has the following form:
Y = 0.1154 х MEIc 1.1628;
Y = 0.5613 х MEIa 1.1786;
where: Y- fish yield, kg/ha/year;
MEIc - Morpho-edaphic Index of Conductivity;
MEIa - Morpho-edaphic Index of Alkalinity.
Originality. This is the first research on the empirical Model development of fish yield prediction for lakes and water reservoirs in Central Asian region. The proposed Fish Yield Prediction Model, developed on the basis of MEI, using the statistical method of analysis, has invaluable practical utility to understand the fisheries potential of lakes and water reservoirs in the region, where such environmental conditions prevail.
Practical value: If reliable data on fish stock assessment in water bodies are unavailable, the proposed model will be used as one of the tools in the management of fish stocks.
Purpose. To develop methods for forming of a replacement-brood stock of the European grayling.
Methodology. In the course of the work, we used the generalized results of the studies performed during 2014-2017. Rearing age-1 and 1+ fish was done 135 m 2 ponds. Water temperature in the winter fluctuated within 2-5ºС.
Findings. During three years, we formed a replacement-brood stock of the European grayling of age-3 European grayling with a total number of 15 fish at the State Enterprise “Trout hatchery “Lopushno”. Eight months before spawning, artificial feeds were removed from the diet of brood grayling and they were replaced by natural feeds. Frozen chironomid larvae were used in the study. The feed conversion ratio of the natural feeds during rearing of brood stock was 6 units that corresponded to 12.82 kg.
The mean weight of domesticated brood fish used for the spawning was 181.3 g, mean length – 25.0 cm. Weights of males varied from 190 to 260 g, those of females – from 134 to 200 g; lengths of males varied from 26 to 32 cm, those of females – from 24.5 to 29.0 cm. Males exceeded the females by mean weight; a similar result was observed for the mean length, where males exceeded the females by 7%. Working fecundity of females was 2762±491 eggs. Fertilization rate was 60%.
Originality . For the first time in Ukraine, a holistic mechanism of scientific principles and methodical recommendations for artificial reproduction of the European graying was developed for the purpose of the following stocking of rivers, aimed at preserving their number in the water network of the Carpathian region.
Practical value. The results of the work are the basis for planning, conducting and controlling the results of the artificial reproduction of the European grayling of the Carpathian region.
Purpose. To determine main the technological parameters of artificial reproduction of sterlet (Аcipenser ruthenus) and Siberian sturgeon (Acipenser baerii) with a combined use of industrial aquaculture methods.
Methodology. The material for the study were brood sterlet and Siberian sturgeon reared in cage conditions in a water body with natural temperature regime of the forest-steppe of Ukraine. The experiments were performed at a regulated water temperature regime at different periods of the spring (March-May) with the use of natural gonad-stimulating hormones for the stimulation of the maturation of sexual products in fish. During the process of the preparation of brood fish for fish breeding works, a recirculating water supply facility was used. The determination of technological parameters and study of physical-chemical factors of the environment were performed according to generally accepted methods.
Findings . At a water temperature of 14-16оС, high efficiency of gonad maturation was observed in sterlet and Siberian sturgeon females with mean weight of 2.8 and 11.6 kg, respectively. The mean weight of eggs obtained from the brood fish was 0.45 kg in sterlet and 1.48 kg in Siberian sturgeon. The mean working fecundity was 43.29 thousand eggs in sterlet and 83.75 thousand eggs in Siberian sturgeon at a relative working fecundity of 15.44 and 7.49 thousand eggs/kg of fish body weight, respectively. During the process of egg incubation, development of fish embryos at the gastrulation stage was on average 87.17% in sterlet and 84.50% in Siberian sturgeon. The output of free embryos of both species from the quantity of embryos on the stage 15 of embryonal development was close to 83-84%.
Originality . Peculiarities of the production of embryos from brood sterlet and Siberian sturgeon with a combined use of different methods of industrial aquaculture in the conditions of a sturgeon farm of the forest-steppe physical-geographical zone of Ukraine have been studied.
Practical value . The results of the study are of interest for the devolvement of modern methods of sturgeon aquaculture in the conditions of an industrial type farm.
Purpose. The State of Israel, for a short period in 1948, despite the difficult political and climatic and geographical conditions, demonstrates a stable development of aquaculture. In this regard, the Israeli experience of cultivating tilapia as one of the main objects of world aquaculture is relevant for Ukraine, especially since these fish species were successfully imported into our country, but not widely used in fisheries.
Findings. Tilapia has become the third most important fish in aquaculture after carp and salmon; worldwide production exceeded 1,500,000 metric tons in 2002 and increases annually. Because of their high protein content, large size, rapid growth (6 to 7 months to grow to harvest size), and palatability, a number of tilapiine cichlids—specifically, various species of Oreochromis, Sarotherodon, and Tilapia – are the focus of major aquaculture efforts.
The work written by the organizer and participants of the of the training course “Intensive Pond Fish Culture”, which was held in Israel in December 2016, is a brief overview of the role of tilapias in the world's aquaculture and the technological schemes by which they are cultivated in this country. In particular, data on world exports and imports of fish in 2016; the gastronomic value of meat is considered; the systematic position of the tribe of tilapias is described; summarizes fish breeding and biological characteristics of the main species used in fisheries. Special attention is focused on the species successfully cultivated in Israel and the technologies that allow it to be achieved. Results of research into tilapia breeding in domestic industrial fish breeding are provided in the article. Ways of effi ciency increase in tilapia breedingare focused in the article.
Practical value. This review can be used to popularize tilapias as aquaculture facilities and upgrade existing technologies for their cultivation in Ukraine, as well as in educational and scientific activities.
Purpose. Determination of the effectiveness of amaranth assimilation in the body of 1+ carp, the study of the effect of this non-traditional feed component on some physiological and biochemical indices of experimental fish and the economic component of their rearing.
Methodology. Fish-rearing and hydrochemical studies were carried out according to generally accepted aquaculture methods. The hemoglobin content in carp blood was determined by the hemoglobin-cyanide method. The number of erythrocytes in carp blood was counted in a Goryaev’s chamber. Protein content determination was carried out according to the Bradford’s method. The concentration of diene conjugates was studied by a method based on the reaction of the optical density of the heptane-isopropanol extract of lipids. The concentration of TBA-active products was determined spectrophotometrically by a color reaction with thiobarbituric acid. The activity of superoxide dismutase (SOD) was determined by the percentage inhibition of the reduction of nitrous tetrazolium in the presence of phenazin methosulfate. The catalase activity was determined based on a change in H2O2 concentration.
Findings. The study was carried out under the conditions of the State Enterprise Lviv Experimental Station of the Institute of Fisheries of the National Academy of Sciences. The subject of the study were 1+ Lubin scaly carp. Carp of the first experimental group received amaranth seed flour added to the main diet as 10% at the end of the culture season for 30 days, while another experimental group received 20%. The control group of carp was fed with grain mixtures during the entire growing period. The conditions of fish keeping were identical according to the experiment goal.
The temperature regime and main hydrochemical parameters in the experimental ponds were within the limits of the normative values throughout the entire growing season.
When feeding 1+ carp with amaranth, a positive effect was obtained for hematological parameters, nutritional properties of meat, activity of antioxidant protection system, and reduction in lipid peroxidation products, namely: an increase in the number of erythrocytes and hemoglobin content (p˂0.05-0.001), a tendency to an increase in protein and fat contents in muscles, increased activity of superoxide dismutase, a decrease in the number of TBA products and diene conjugates in blood serum.
Originality. Peculiarities of growth, development of carp and efficiency of using feeds of various compositions with the addition of amaranth seeds against the background of similar satisfactory growing conditions were studied for the first time. At the same time, the effect of amaranth on physiological and biochemical parameters of the body of experimental fish was investigated.
Practical value. Based on the analysis of changes in the physiological and biochemical functions of fish organism and economic efficiency as a result of feeding fish with amaranth, quantitative norms and methods for adding it to the diet of carp were developed.
Purpose. To analyze the effect of different concentrations of inactivated baker's yeast on the growth rate of Russian sturgeon fingerlings and the associated metabolic processes to establish the optimal concentrations that could be used in the feed composition for the above-mentioned fish, which are cultivated in recirculating aquaculture system (RAS).
Methodology. To achieve the purpose of the work, classical ichtyological and biochemical methods of research were used. So, during the experiment, regular measurements of the mass of fish were performed, mortality was calculated, samples of tissues were selected for further evaluation of the physiological and biochemical status of the organism. The results were processed using variational statistics methods using the standard Microsoft Office Excel package.
Results. The influence of various concentrations of baker's yeast in the composition of feed for Russian sturgeon on its growth and survival rates is demonstrated. In particular, it was found that their concentration of 5% on the diet within two weeks after transition to exogenous nutrition is optimal.
Scientific novelty. For the first time carried out the analysis of the influence of different concentrations of inactivated baker's yeast, as part of the diet of Russian sturgeon fingerling, on his growth potential.
Practical significance. It has been proved, that inactivated baker's yeast is appropriate to be introduced into the started diet for Russian sturgeon, since it has a positive effect on his digestive system and stimulated growth potential.
Purpose. To create a thematic bibliographic list of publications on studies of ecological and biological characteristics of the Black Sea roach (vyrezub) Rutilus frisii frisii Nordman, as an endangered cyprinid species of the fish fauna of Ukraine.
Methods. The complete and selective methods were applied in the process of the systematic search. The bibliographic core has been formed with the publications exclusively in Ukrainian and Russian from the fund of the scientific library of the Institute of Fisheries NAAS of Ukraine.
Results. There was composed a thematic list of publications with a total quantity of 37 sources covering a time interval from 1931 to 2017 devoted to the questions on the study of the geographical distribution, morphological and ecological characteristics, biological features of different developmental stages, as well as the specifics of reproduction and technologies of pond and industrial rearing of a Red Book fish species, the Black Sea roach, in the context of biodiversity conservation. In addition, the list includes publications on problems of the restitution of this species in river basins. The literary sources are arranged in alphabetical order by author or title, and described according to DSTU 8302:2015 “Information and documentation. Bibliographic reference. General principles and rules of composition”, with the amendments (code UKND 01.140.40), as well as in accordance with the requirements of APA style — international standard of references.
Practical value. The list may be useful for scientists, practitioners, students, whose area of interests covers the questions of biological studies, and problems of the restoration and conservation of the Black Sea roach as an endangered object of fish fauna.