It was ascertained that the brood material of rainbow trout available in the Republic of Belarus represents the valuable genetic material adapted to the conditions of fish breeding farms of Belarus quite capable of producing proper offspring. There are defined reproductive properties of selected ensemble (25 females) of rainbow trout. There was ascertained the correlation dependence between a female body weight and its industrial fecundity.

There were presented the comparison results of relative weights of trout females and males body parts from two populations adapted to the conditions of Belarus generated from the genetic material imported to Belarus.

There is provided a description of exterior morphometrical properties of trout underyearlings taken from two populations imported from the Russian Federation and France at the phase of impregnated row. There were discovered the differences between the underyearlings of various origin in terms of absolute and relative properties.

The paper provides the data on biochemical composition (content of dry substance), moisture, fat, protein and minerals in the muscles of two years bions of trout. There is described the variability of the said indicators of the representative sampling, there is shown the comparison of the data obtained with rated standards. Using Spearmen’s rank order correlation there was ascertained the interrelation of some biochemical indicators with fish mass and Foolton’s coefficients of condition.

There are presented the results of comparison estimation of carp female fecundity of belarussian selection lines and broods imported to Belarus. There was ascertained high variability in terms of female industrial and relative industrial fecundity which made possible to select some bions showing the increased fecundity. From the selected females there was formed a group used then as a genetic pool for further selection activities.

By now in the Republic of Belarus there has been formed a collection genetic pool of carp lines and broods of domestic and foreign selection, including Amur Cyprinus carpio from Khankai population. For recruit-stocking of replacement repair school there is ensured annual obtaining of purebred of fsprings on the basis of which by means of mass selection method in compliance with breed standard there is generated junior replacement repair for collection broods and lines. There is provided fishery characteristic of un deryearlings for collection carp schools.

The essay provides the charts of reciprocal crossings, morphopmetrical properties of carp pertaining to various broods and also the data on reproductive qualities of carp females. The imported broods are marked by the improved phenotypical qualities as compared to the broods of belarussian selection. The offspring obtained as the result of crossing these broods with the domestic ones shall have the improved merchantability due to heredity of the European broods used.cr

There has been performed summary analysis of the situation with fish diseases in the Republic of Belarus: there were defined the causes for development and spreading of fish diseases, listed the most hazardous aspects for fish breeding establishments, emphasized the importance of diagnostics and preventions of the diseases in due time manner. There was identified the role of ichthyopathology in modern economy, its relation with other spheres of fish breeding, set force the main tasks which are to be solved in future.

There has been produced the medicinal product Diplocide for prevention and treatment of fish diplostomoze. The efficiency of the medicinal product against the said diseases was confirmed by the tests and in industrial conditions. Death of pathogenic agents metacercaria p. Diplostomum at the result of medicinal product application attained 100%. There was elaborated regulation documentation application of the medicinal product Diplocidew in fish breeding farms.

The article provides the data on combined fodder production in the Republic of Belarus. There was shown the comparison analysis of combined fodder production volume with account of their quality parameters for various types of fish, there were analyzed the existing defects at production of fodder and defined the relevant trends of scientific researches for the prospects.

There was ascertained the positive influence of B12 vitamin, hydrolactive, amber acid and epibrassinolide for Lena surgeon ich fry for the time of holding prior to shifting to exogenous feeding that was manifested in increase of ich fry body length and body and their survival ability. Vitamin C, hydrolactive and amber acid had favorable impact on morphological and biological indicators of Lena sturgeon ich fry during growing which was manifested in decrease of organic and somatical indicators of heart, liver and kidneys and improvement of hematological indicators.rp

There are described the results of growing commercial two years carp at low densities of stocking. It was ascertained that use of large size carp stocking material (50) contributes to better implementation of growing potential at the second year of life and to obtain two years bions of greater mass (over 500 g) at less fodder consumption as compared to intensive growing technology.

Hematological researches performed demonstrated that the maximum level of hemoglobin concentration was attained at eight years old bions of paddlefish which occurred due to male puberty. The concentration of hemoglobin, erythrocytes and leucocytes with nine years old paddlefish bions is higher as compared to eleven years old paddlefish bions. At the result of studying paddlefish blood serum samples it was discovered that nine years old paddlefish more intensely are subjected to stresses and physiologically are more unbalanced as compared to eleven years old bions

There was demonstrated the efficiency of sylvinite application in the ponds as the desorbing substance which causes the mobilization of biogenes from the soils that contributes to photosynthesis intensification in the ponds, increase of natural fodder supply and fish capacity at decrease of fodder consumption and also costs and expenses for application of mineral fertilizers for a unit of pond area.

There were worked out the technological methods of growing the merchantable carp of increased weight conditions at two years circulation allowing to obtain two years old carps of mass over 500 g in the conditions of the Republic of Belarus with capacity from 8.5 to 10.6 c/ha.

On the grounds of the experiments carried out under production conditions on extending the feeding period of carp underyearlings it has been ascertained that withdrawal of yearlings from hibernation is within the rated limits and body weight loss is by 1.46-1.75 times less as compared to carp body weight with the limited feeding period.

There was studied the growth of carp Cyprinus carpio underyearlings in pond conditions of the Republic of Belarus. There was suggested a new calculation method for defining the content of moisture, dry mass and also energy value of carp underyearlings. Its application demonstrated the possibility of defining the values of these indicators in the process of growing the fishes without regular biological investigations in place.

The article stresses that maintaining of sturgeon population in Dnieper river is now directly dependent on the performance of the only in Ukraine specialized enterprise - Dneprovskiy sturgeon fish breeding factory. During the 30- year period (1985 - 2014) of its work in the lower Dnieper and Dnieper-Bug Estuary were introduced 48,080,000 ind. of juvenile of Russian sturgeon, 1,780,000 ind. Of stellate, 40,000 ind. of Beluga, 40,050,000 ind. of starlet.

At sturgeon fish-breeding plants on the captive breeding in the Astrakhan region at cultivation of young fishin ponds a negative factor is contamination their listonogy crayfish (leptesteriya and shchitn) which oppress development of valuable fodder organisms in nursery reservoirs. The applied a chloric method of fight against listonogy crayfish has an essential shortcoming - lime chloride negatively influences on body height and development of the main valuable objects of a delivery of the sturgeon. The offered intensifikatsionny actions based on non-chlorine processing of nursery ponds allow to improve their food supply and to raise a ryboproduktivnost of reservoirs.

There is investigated the effect of the cage culture fishery line formed in the lake on biogenic contamination of water reservoir. There is available the data on hydrochemical conditions of water reservoir prior and after establishing cage culture fishery line, development of phyto and zooplankton, level of biogenic stress introduced. There was shown that the main contamination of ecological system is caused by the fodder used and fish metabolite, but sufficient amount of dissolved forms of mineral phosphorous even the excessive increase of mineral nitrogen does not cause structural recombination of trophy elements of the water reservoir.

There were reviewed some peculiarities in dynamics of species composition and quantitative development of phytoplankton in two small lakes at biological manipulation with application of predatory fish in progress. There was estimated the qualitative importance of dynamics and there were set force the possible assumptions on the interconnection between the changes discovered with hydrochemical condition and development of backboneless plankton.

There is investigated the effect of the cage culture fishery line formed in the lake on biogenic contamination of water reservoir. There is available the data on hydrochemical conditions of water reservoir prior and after establishing cage culture fishery line, development of phyto and zooplankton, level of biogenic stress introduced. There was shown that the main contamination of ecological system is caused by the fodder used and fish metabolite, but sufficient amount of dissolved forms of mineral phosphorous even the excessive increase of mineral nitrogen does not cause structural recombination of trophy elements of the water reservoir.

The article provides the comparison analysis of biological diversity of ichthyo- fauna in some areas of Amur river basin differing by the degree of human induced load. There were discovered the differences in quantity and quality describing the biological diversity of ichthyofauna of Zabelovka River basin and bottomland water reservoirs of water basins of Tungusska, Bira, and Bidzhan rivers.

All 7 ponto- caspian species of fish-immigrants found in Belarus (monkey goby, goad goby, round goby, tube-goby, starry goby, needlefish and small southbansticle) are observed only in the bottom area of Dnieper river within Bragin region. Upstream of Dnieper river the quantity of species immigrants is decreased and at top region (Dubrovenski region) of water flow only one species monkey gody is observed.

There were investigated 22 water flows of Pripiat Polessie. At the result of work there were discovered and mapped spawning grounds of main commercially important species of fish. There is also available brief description of the said spawning grounds (their location) with indication of species composition of spawning fishes

Deterioration presently observed (first of all in terms of quantity) the state of populations of some representatives of original ichthyofauna of the internal water reservoirs of Ukraine determines the necessity of compensation activities on stocking. Full scale planting of viable fingerlings of pike perch, pike, catfish and European grayling shall ensure 13-68% recruitment increase and taking into account the availability of free ecological niches shall significantly affect the reproductive capacity of their populations.