Rybohospodars'ka nauka Ukrayiny (Fisheries Science of Ukraine)

30-42

Authors: K. Geina, S. Shashlykova, M. Koziy

Purpose. To analyze sexual dimorphism of the Black Sea sprat Clupeonella cultriventris (Nordmann, 1840) of the Bug lagoon under current conditions. To study the dynamics of changes in mesonephros structure during spawning migration from the estuary to the Southern Bug River. To determine the prospect of using the data of histological monitoring in ichthyological practice for the assessment of fish morphofunctional status. Methodology. Primary materials were obtained during scientific and commercial fishery surveys carried out in the Dnieper-Bug estuary system. Control stations were located along the spawning migration pathways of the Black Sea sprat from the Bug lagoon to the South Bug River. Field and laboratory processing of ichthyological samples was performed according to generally accepted methods and guidelines. Histological studies were performed using author’s equipment and original methods specially intended for fish tissue diagnostics. Findings. The studies indicated on the presence of a significant sexual dimorphism in the Black Sea sprat Clupeonella cultriventris (Nordmann, 1840) of the Bug lagoon. The comparative analysis of twenty-four plastic features showed that sprat females had a higher body depth (td=6.11; р<0.05), shorter body (td=8.62; р<0.05)and caudal peduncle (td=7.64; р<0.05). Females also had the displacement of fins in the caudal direction that that was manifested as a significant difference between antedorsal, antepectral, anteventral, anteanal, pectoventral, and ventroanal distances (td=4.39-9.67; р<0.05). Linear parameters of fins (length, height) also differed significantly (td=3.96-11.23; р<0.05). It is important to mention that these features in females were larger than those in males. An exception was the anal fin height, which was significantly higher in males than in females (td=6.85; р<0.05). No differences were detected for abdominal fin length (td=0.03; р<0.05) that was also typical for head length (td=0.15; р<0.05). No significant differences were detected in the head area. A significant differences was observed only for eye diameter and postorbital distance (td=4.15-7.99; р<0.05). Studies of microanatomical feature showed that osmolarity fluctuations of aquatic environment had a significant effect on changes in the histological structure and functional peculiarities of the nephrogenic tissue through the reduction in the diameter of Bowmen-Shumlyansky's capsule by 7.0 µm. The reduction in the functional activity of renal convolute was demonstrated by the reduction in the height of cubic epithelium cells of convoluted tubules by 3.0 µm. Localization of ion-transporting cell groups near vascular elements and tubular epithelium indicate on the participation of mesonephros in ion-regulating processes that increase the resistance of fish to the changes in water salinity. If osmolarity of aquatic environment reduces, functional nephron activity in sprat kidney changes that is manifested as a reduction in the diameter of renal bodies and height of the epithelium of proximal convoluted tubules. Originality. The paper contains new and significantly updated already existing data on the structure of the Black Sea spat spawning stock of the Dnieper-Bug estuary system. A histological analysis of the mesonephros structure of mature Black Sea sprat was performed for the first time. Information on taxonomic peculiarities of adaptation changes in the nephrogenic tissue in the condition of spawning migration was specified and complemented. Practical value. The obtained information is valuable for morpho-physiological studies as well as for ichthyological practice due to the existing current problem of the decrease in the vital status of sprat because of the reduction in the stocks of a number of valuable commercial fish species in delta areas of the river systems of Ukraine.

58-70

Authors: B. Gankevych, O. Tretyak, O. Kolos

Purpose. To investigate the peculiarities of heavy metal (Fe, Zn, Mn, Cu, Ni, Co, Pb, Cd) accumulation in organs and tissues of the North American paddlefish Polyodon spathula (Walbaum) introduced into inland water bodies of Ukraine. Methodology. The objects of the study were age-4-7 paddlefish reared in ponds of the forest-steppe and forest area of Ukraine. Age-3 carp as well as hybrids between the bighead and silver carps reared in polyculture with experimental groups of the paddlefish were used for comparative evaluation of the peculiarities of heavy metal accumulation in fish muscular tissues. The studies of the heavy metal content in pond water, fish organs and tissues were performed with the use of generally accepted toxicological methods. The quantitative contents of heavy metals were determined with the aid of the atomic-absorption spectrophotometer C-115-M1. Findings. The toxicological state of the experimental ponds was characterized by elevated values of the contents of Mn (by 8.5-8.9 times), Cu (by 2.1-3.9 times) and Pb (by 1.5-1.80 in water. The concentration of other heavy metals in water did not exceed the allowed values. Similar patterns were found regarding the heavy metal distribution and accumulation in paddlefish organs and tissues as for carps. No maximum allowable concentrations of heavy metals were detected in the muscular tissues of the paddlefish. Among all studied fish reared in polyculture, the paddlefish had the lowest content of Cu, Co, Pb and Cd in muscles. The mean heavy metal contents in paddlefish muscles in the studied ponds of forest-steppe and forest area were: Fe (4.64-29.60), Zn (1.20-5.54), Mn (0.10-0.23), Cu (0.09-0.44), Ni (0.28-2.15), Co (0.10-0.13), Pb (0.63-0.94), Cd (0.031-0.037). Originality. The peculiarities of the distribution and accumulation of heavy metals in organ and tissues of the North American paddlefish reared in the conditions of pond farms of Ukraine have been studied for the first time. Practical value. The study results is an essential component of the material for the creation of a database for the determination of product quality of domestic sturgeon culture, in particular regarding the peculiarities of heavy metal accumulation in fish.

81-88

Authors: M. Pashko, O. Tretiak, O. Kolos

Purpose. To study the peculiarities of the artificial production of ovulated eggs from brood sterlet at non-traditional terms and to determine major productive parameters in experimental fish groups. Methodology. The object of the study were sterlet females of different ages with body weights 1.4–3.3 kg reared in the conditions of a farm of industrial type in a water body with natural temperature regime for the forest-steppe zone of Ukraine. The experiment was performed under regulated water temperature regime during the period from January to March with the use of natural gonadotropic preparations for the stimulation of fish gonad maturity. A recirculating aquaculture system was used during the preparation of brood fish for the study. Determination of productive parameters and study of physical-chemical factors of the environment were performed according to generally accepted methods. Findings. High efficiency of gonad maturation was observed in all experimental fish under water temperature of 14.0-16.5oC. Mean weights of sexual products obtained from brood fish in different experimental variants were 130–384 g. Mean working fecundities and relative working fecundities of sterlet females varied within 13.42–36.83 thousand eggs and 8.80–13.40 thousand eggs/kg of fish weight. General duration of fish maturation from the beginning of hormonal stimulation until the moment of the beginning of egg ovulation changed on average from 407.6 to 587.4 degree-hours. Originality. The peculiarities of the production of mature eggs from sterlet females with the use of industrial reproduction of sturgeons, which is new for Ukrainian aquaculture, have been studied. Practical value. The study results can be useful for the development of advanced methods of sturgeon aquaculture in the conditions of industrial fish farms.

103-115

Authors: R. Palamarchuk, O. Deren

Purpose. Determination of the effect of adding an Amaranthus (Amaranthus) supplement with anti-oxidant properties to the basic diet of carp on some fish-physiological parameters depending on rearing conditions. Methodology. Aquaculture, ichthyological and hydrochemical studies were conducted according to generally accepted methods in fish culture. The hemoglobin content in carp blood was determined by hemoglobin-cyanide method. The number of red blood cells in the blood of carp was counted in the Goryaev’s chamber. Determination of protein content was carried out using the Bradford’s method. The concentration of diene conjugates was estimated by a method based on the reaction of the optical density of the heptaninopropanol lipid extract. Determination of the concentration of TBK-active products was carried out spectrophotometrically by color reaction with thiobarbituric acid. The activity of superoxide dismutase (SOD) was determined by the inhibition of the reaction of nitrosin tetrazolium reduction in the presence of phenazine methisulphate. The activity of catalase was evaluated based on changing H2O2 concentration. Findings. The study analyzed the effect of feeding carp with grains of Ukrainian high-yielding feed grade amaranth with healing properties (Kharkiv-1) on physiological and biochemical parameters of fish organism. A comparative description of the efficiency of using this feed supplement under standard conditions of cultivation and the effect of a stress factor (water pollution as a result of intensification measures) was carried out. In both experiments, an increase in the number of formed blood elements was observed in the blood of experimental groups of fish: there was a tendency of an increase in the number of erythrocytes by 15-18.1% compared to control. Under optimum conditions of rearing, there was a tendency for an increase in body fat in the experimental group carp carps, while the effect of stress factors increases the protein (p<0.01) and fat contents compared to control. Under optimal conditions of cultivation, the tendency of an increase in SOD activity, both in muscles and in hepatopancreas of carp (by 5.9-8.3%.) was observed. Under the effect of stress factors, the activity of this enzyme was significantly increased (p˂0.01 ) that indicated on the activation of the anti-oxidant properties of amaranth in the event of negative factors. Originality. For the first time the effect of biologically active properties of amaranth on some fish and physiological parameters of age-1+ fish was studied and the effectiveness of its use under optimum conditions of cultivation, as well as the effect of stress factor was determined. Practical value. Laboratory simulation of high content of nitrites in water, as widely common stress-factor in fish farming, and comparison of its effect on some fish-physiological parameters of carp organism is justified and topical. Taking into account positive results of the introduction of this feed additive into the diet of carp, it is possible to solve the problems of fish farms caused by the intensification of production, namely: reduction in fish growth gain and their death due to hypoxia and the development of concomitant diseases as a result of organic pollution of the aquatic environment.

130-136

Authors: B. Grishyn, I. Hrytsyniak, I. Osoba

Purpose. To characterize some physiological-biochemical peculiarities of cross-bred carp of the first generation from crossing Antoninsko-Zozulenets and Lubin intrabreed types of Ukrainian framed breed. To establish the peculiarities of protein metabolism in the organism of the studied carp groups. Methodology. Classical biochemical methods of the determination of protein concentration and ratios of its fractions in tissues were used for the study. Findings. Peculiarities of protein metabolism in the organism of cross-bred carp of the first generation from crossing Antoninsko-Zozulenets and Lubin intrabreed types of Ukrainian framed breed were demonstrated. In particular, data on protein content in skeletal muscle tissues and hepatopancreas of the studied fish groups were provided. Scientific novelty. An analysis of protein metabolism in the organism of cross-bred carp of the first generation from crossing Antoninsko-Zozulenets and Lubin intrabreed types of Ukrainian framed breed was performed for the first time. Practical value. Protein metabolism defines physiological-biochemical homeostasis of fish organism in a significant degree. Therefore, protein concentration in tissues as well as the ratio of some protein fractions play an important role in the evaluation of biological peculiarities of the examined carp groups and reflect the functioning of major metabolic systems in fish organism.