Rybohospodars'ka nauka Ukrayiny (Fisheries Science of Ukraine)

29-39

Authors: O. Marenkov, O. Fedonenko, E. Filippova

Purpose. To analyze the current state of the populations of roach, bream, pikeperch and silver bream in the Zaporozhye (Dnipro) reservoir and to determine the acceptable amounts of commercial harvest of these fish species for 2017 by determining scientifically justified limits. Methodology. The summarized results of ichthyological studies conducted during 2010–2016 years were used during the research. The materials were collected in the Zaporizhzhya (Dnipro) Reservoir using standard fish sampling methods. A set of standard fishing gears (gill nets with mesh sizes of 30–120 mm) was used for studying fish fauna. Juvenile fish were caught in the third decade of July – first decade of August using a beach seine of 10 m in length. The processing of collected samples was conducted by conventional methods. Findings. We studied the current state of commercial fish populations, the exploitation of which is limited (roach, bream, pikeperch, silver bream). We determined the basic biological parameters of these species, determined the age and sex structure of their populations and assessed their stocks. Based on these data, we determined the rates of natural, fishing and total mortality and calculated the amounts of commercial catches of the investigated fish species. With an optimum catch of the roach not exceeding 25% of the calculated stock, we recommended to set a limit on the catch of this species for 2017 as 190 tons. Next year, it is advisable to set a limit for the bream catch not higher than 88 tons. Due to a critical state of the pikeperch stock in the Zaporozhye (Dnieper) reservoir, the recommended limit of its catch for 2017 should not exceed 14 tons. The estimated catch limit for the silver bream for the following year is recommend to be 70 tons. The harvst of these fish species within the proposed limits will allow carrying out their commercial exploitation without environmental damage. Originality. We presented the results of the study of the stat of commercially important fish populations, the harvest of which is limited annually. These approaches to the commercial harvest of the roach, bream, pikepearch and silver bream are aimed at introducing and implementaing the scientific justification of commercial fish exploitation in the Zaporozhye (Dnipro) reservoir. Practical value. Determination of the proposed commercial harvest limits for the roach, bream, pikeperch and silver bream ensures a rational use of aquatic living resources and conservation of the stocks of the commercial fish species in the conditions of fishing pressure.

52-63

Authors: Ye. Alkhimov, V. Shevchenko

Purpose. Examine and analyze the current state of storage fingerlings acipenseriformes cultivation, including sturgeon and paddlefish, in terms of industrial-experimental Dnieper sturgeon fish-growing factory located in the southern Ukraine. Methodology. The problems were solved by the conventional methods in hydrochemistry, hydrobiology and fish farming. The results were processed using statistical methods of the data processing and analysis which suggest it reliable. Findigs. The research has established that physical and chemical parameters of water in farms' ponds answered the operating pond fishery regulations. The existing level of natural forage base elements can be considered satisfacting for the growing storage material. The best development of zooplankton in the application of polyculture acipenseriformes should be noted. The monoculture benefit was observed in the most fisheries indicators for certain types. Sturgeon fish productivity advantage in terms of polyculture is the evidence of positive mutual influences among the reservoir consumers of different trophic levels. In terms of polyculture the significant benefit of total fish productivity indicator was observed. It clearly points to the prospects of the measure in terms of substantial efficiency of pond areas for growing storage fingerlings. Results of acipenseriformes growing in mono- and polyculture clearly favor the polyculture, which could be used in breeding practice. Scientific Originality. In specific conditions of the southern Ukraine the influence of environmental and technological conditions for growing storage fingerlings acipenseriformes fish (sturgeon and paddlefish) was investigated for the first time. In terms of mono- and polyculture cultivation storage acipenseriformes fish material was firstly explored. Practical Value. The results of cultivation can be used in breeding practice as the norm of the environmental situation evaluation in the ponds. Growing storage fingerlings acipenseriformes in polyculture allows better usage of the natural food base, improving productivity and efficient usage of farms' water growing areas.

73-83

Authors: M. Korylyak, I. Hrytsyniak, O. Deren, O. Dobrianska

Purpose. To study the effect of thistle seeds introduced into the basic diet of carp, the functional state of antioxidant protection (AOP) and the formation of lipid peroxidation products (LPP) in fish hepatopancreas. Methodology. The study has been carried out at the Lviv Research Station of the Institute of Fisheries in duplicate. The first replication was done in 2013, the second one in 2014 at industrial conditions of ponds with similar areas and with the same source of water supply. The object of the study were age-2 Lubin scaled carp. The experiment consisted of four variants and lasted 60 days. The control group of carp received a complete combined feed without additives during the entire growing season, while the experimental groups 1, 2 and 3 received feeds supplemented with 1, 5 and 10% of milled thistle. Thistle was introduced into the feed composition by granulation method. At the end of the experiment, tissue samples of the experimental groups of fish were taken for biochemical analysis. We used 10% tissue homogenates of carp hepatopancreas. We investigated the concentration of diene conjugates using a method based on the reaction of optical density of lipid heptanizopropanol extract. The determination of TBA-active products was carried out spectrophotometrically based on the color reaction with tiobarbitur acid. The activity of superoxide dismutase (SOD) was studied by determining the percentage inhibition of nitroblue tetrazolium reduction reaction in the presence of fenazynmetasulfate. The activity of catalase was analyzed based on the concentration of H2O2. The determination of protein content was performed by Bradford method. The processing of experimental results was performed by variational statistics. Statistically significant difference was assessed using a Student t-test. Findings. As a result of experimental studies in industrial conditions in duplicate, we detected AOP activation and reduction in LPO process intensity in hepatopancreas of all three experimental groups of carp, which received the feed supplemented with 1, 5 and 10% of milled thistle as compared to the control. This trend was more pronounced when using 1 and 5% of this additive in feed composition. In particular, the SOD content significantly increased (P<0.001) in the first replicate and there was a trend for its increase by 13.8–58.2% in the second replicate as well as a reduction in the concentration of the end lipid peroxidation products of LPO (MDA) by 19.9–73.7%. Thus, the use of thistle has a positive effect on antioxidant system on age-2 carp, which in turn will have a positive effect on the functional state of their organism. Originality. The problem of finding the means to mitigate the impact of stress factors on carp, which arise during their rearing, is relevant in today's conditions, since they adversely affect the functional state of fish organism as a whole. An effective way to solve this problem is to use feed supplemented with substances with antioxidant properties. Taking into account the positive results in animal husbandry and some experience in fish farming, the studies of the efficiency of the use of thistle in feeding carp and the determination of norms and methods of its prolonged addition to the diet of carp is an urgent task that has both scientific and practical importance. Practical value. The determination of a positive effect of the use of thistle seeds in carp feeding on the activity of the course of oxidative processes in fish body will allow fish farmers to obtain a cost-effective and environmentally safe mean of levelling the stress factors that have a negative effect on fish during their rearing, at the same time directly influencing on the productivity of fish ponds.

92-117

Authors: M. Simon

Purpose. To analyze scientific sources on the physiological, biochemical, ecological and genetic features of the main hematological paremeters and patterns of their variability in sturgeon species (Acipenseridae). To examine the fundamental aspects of lipid and protein metabolism in blood serum and the effect of biotic and abiotic factors on them. To highlight the common features of serum enzymes. Findings. A review of scientific papers revealed that although hematological parameters of sturgeons are generally similar to those of teleosts and mammals, there are a number of significant differences. In addition, many hematological parameters are characterized by species specificity, even within a family. Special attention is given to the variability of hematological parameters under the effect of factors of both internal and external environment. The paper describes the effects of sex and age, as well as the seasons of the year on the compositio of sturgeon blood. The fundamentals of the use of serum proteins in genetic and population studies are outlined. The features of the functioning of hemoglobin in sturgeon’s red blood cells are examined. The main hematological parameters involved in the formation and maturation of sexual products, and their effect on fertility are reviewed. For example, the spawners, which hadn’t put reproductive product, are characterized by a low rate of hemoglobin, increase in erythrocyte sedimentation speed and also a rise of the level of crude protein in blood and β-lipoproteid serum.The biochemical parameters (total protein and fractions, glucose, creatinine, cholesterol), the activity of some enzymes (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase) in serum are examined. Practical value. The systematized data on the main hematological parameters and patterns of their variability in sturgeon species will be useful for both scientits and fish farmers. This is due to the fact that the analysis of blood as the most labile system of fish organism, not only clearly reflects the physiological state of the individual in specific conditions of existence, but is also used in genetic and population studies. Thus, the knowledge of the basic patterns of the formation of blood composition of sturgeon fish is necessary for further research in fisheries science. An array of the generalized information will be useful for the creation of replacement broodstocks, assessment of the quality of juveniles, determination of the readiness degree of broodfish for spawning, in ichthyopathological situations at fish farms, etc.