The article provides a comparative description of fish consumption by the population of Belarus in 2019, 2018 and 2017 according to the results of a sociological survey on the preference of fish species and their frequency of consumption. Trends in the preference for fish products by the population are reflected. The actual directions of fish farming related to population demand are shown.

As a result of the study the ratios of body parts and the exterior characteristics of two-year-old fifth generation breeding mirror carp were determined. Evaluation of breeding carp compared with the best mirror analogues and amur carp, grown together.

Tribal groups of carp of different species belonging to the Belarusian and foreign breeding, amur carp, originating from the Khanka population included in the collector's herd SPU "Isabelino" and hybrids of carp with the carp examined the complex fisheries biological characteristics. The article presents the results of the study of exterior indicators of carp of different origin and hybrids of carp with amur carp.

The article presents the results of a study of the ratio of edible and inedible body parts of two-year-old carp hybrids of the Belarusian and foreign selection with the collection population of the ninth generation amur carp grown in a pond farm of Belarus. Based on the study of interior indicators of hybrids, amur carp and carp of different origin, statistically significant differences were established when comparing certain characteristics of groups of different origins.

The article presents the results of genotyping at transferrin locus of 7 and 8 generations of the Amur wild carp (Khankai population), included in the collection gene pool of the Republic of Belarus, in comparison with the brood stock of the 4 generation.

The most effective complex microbial consortium, developed on the basis of the 3 most active strains of nitrogen-fixing and phosphate-mobilizing bacteria from p. Pseudomonas, isolated from the water and soil of fish ponds was found in model experiments. Single norms of microbial consortium for introducing it into fish ponds were determined.

The efficiency of the microbial fertilizer BaktoFish in nursery ponds are presented. Microbal fertilizer application leads to enrichment of the aquatic environment with nutrients, an increase in natural fish productivity and a reduction in the cost price of young carp at 4,0%.

Different-aged sterlet (fingerlings, two-year-olds, three-year-olds) on the majority of studied signs is characterized by insignificant and everage level of variability. The pronounced variability of body weight in sterlet of three generations was established, the coefficient of variation reached 36,65 %-39,83% and the population on basis can be characterized as heterogeneous. Found that sterlet three ages there is a positive correlation of body mass with the length of the fish and antedorsal distance , and two-year-olds and a three-year-olds sterlet in addition to these two signs still existed a very close relationship of body weight with the distance between pectoral and pelvic fins, girth of body and the maximum height of the body.

In technology of artificial reproduction of sturgeon fishes an important point is the sperm storage period as it is demanded by various technological situations (a delay of maturing of females, need of transportation, etc.). The known way of storage of sperm is its cryopreservation. The researche on the example of the Siberian sturgeon established that, unlike boric and wine acids which positive influence was established by us in the previous researches Zincum has no reliable impact on quality and quantitative indices of sperm of the Siberian sturgeon during short-term storage.

In this article are presented the results of application the fodder protein additive “Extra” at the feeding a different age carp in fishponds. The results are showed that established norms of input of fodder protein additive in compounding confirmed the possibility of using it in mixed fodder.

Scientific assessment of efforts for eel conservation in the Republic of Belarus is made. Complex system of measures was developed and under implementation in Belarus on protection and recovery of the stock of European eel, including measures on implementation of EU Council Regulation dated 18.09.2007 № 1100/2007. It is shown that Republic of Belarus has great potential on European eel world population conservation.

Current goldfish wide spread in Belarus is the result of purposeful acclimation started in 1948, when both unisexual and bisexual goldfish forms from the Amur river basin were introduced. The goldfish established in Belarusian waters by the second half of 1950s. The goldfish adaptation to the new conditions led to change of some populations reproduction type from unisexual to bisexual. We suppose it is the result of the crucian carp gradual replacement by goldfish.

Some hydroecological parameters of the Dnepr River within five districts of the Vitebsk, Mogilev and Gomel regions are considered. The established indicators make it possible to single out the pronounced upper and middle sections of the flow, with the formation of the transition in the sections of Shklov - Mogilyov. Concentrations of total nitrogen in the territory of Belarus from the border with the Russian Federation tend to decrease, which indicates an increase in the rate of self-cleaning processes. At the same time, there is a slight increase in the concentrations of nutrients below cities, which indicates secondary sources of pollution. The distribution of the main groups of hydrobionts is consistent with the hydrological conditions of the areas under consideration. A general tendency to a decrease in the value of oxyphilic forms of zoobenthos from upper to lower levels and an increase in the value of mollusks in macrobenthos was noted.

The issues of the current state and structure of the fish population of the Dnieper River on the transboundary Belarusian-Russian section of the Dnieper River are considered. It is established that the ichthyocenosis of the analyzed area of the river. The Dnieper is represented by 33 species of fish belonging to 9 families. Brief characteristics of the main biological indicators and the quantitative development of individual rare and most common fish species are given. Data are presented on stocking a section of the river with rare fish species in order to form their stable native populations.

There is presented influence of climate changes on the species composition and number of ichthyofauna of the Dnieper reservoirs

The introduction of the most effective phosphate-mobilizing (Pseudomonas lini BIM B-485D, isolates 1T, FM 1.3) and nitrogen-fixing (Rhizobium rhizogenes BIM B-486D, isolates 8AT, 11AT) bacteria increases the number of phosphate-solubilizing and nitrogen-fixing microorganisms in the pond water. These microorganisms are promising for use as components of microbial fertilizers for fish ponds to reduce the dose of applied NP-fertilizers to provide fish ponds with “biological” phosphorus and nitrogen and consequently increase pond productivity in environmentally friendly manner.

In modern society at the global level, there is the problem of pollution of atmosphere, hydrosphere or lithosphere. It is believed that the contaminating agents are regularly entering the human body, about 70% comes from food, 20% from air and 10% water. The nitrate problem is the problem of modernity. Therefore, the sounding range of issues on the problem of "nitrate", the awareness of them in society, disclosure of the effects of nitrate and nitrite on the processes of vital activity of biological objects should take on a regular basis.

The article informs about the results of the research on the contamination of carp (Cyprinus carpio L.) by invasive species of causative agents of gelment and bacterial nature, depending on the age of fish on the fishing farms in Belarus. The composition of alien species of gelments (Khawia sinensis (Hsu, 1935), Bothriocephalus acheilognathi (Yamaguti, 1934), Philometroides lusiana (Vismanis, 1966)) and bacteria (Shewanella putrefacies и Aeromonas hydrophila), their incidence in the population of carp was stated. The dependence of the change of contamination by invasive species of gelments and bacteria on the age of this kind of fish was identified. It was revealed that the incidence of gelments and bacteria in the population of carp increases with the age of carp.

Information on the cases of diplostomosis in fish breeding in aquaculture of Belarus is presented in this article. The analysis was carried out on the data obtained as a result of scientific research and business contracts by the staff of the Fish Diseases Laboratory of the RUE “Institute of Fisheries” from 2005 to 2019. A total of 5391 samples were examined, of which 1407 (26 %) were positive. The data obtained indicate that the causative agents of diplostomosis were and reman widespread among fish breeding in pond-type fish farms.

Studying the influence of stress of various origins on homeostatic and fish- breeding indicators of fish is an urgent problem, both for assessing reproductive potential and for developing measures to eliminate negative consequences. The dependence of the level of cortisol in the blood serum of trout from the time of capture is shown.

The formation of resistance in fur animals of farms depends on the influence of various factors, especially feed and their quality. The use of fish-containing feeds with increased acid and peroxide values leads to metabolic disorders in animals, accompanied by the development of pathological changes in the internal organs, antioxidant and immune systems. There is shown the effectiveness of the method of healing fur animals of farms.

The paper presents the results of studies on carp yearlings infestation by ectoparasites Lernaea cyprinacea and Dactylogyrus vastator in fish ponds farms in Lviv region. Established that fisheries indicators experienced significant fluctuations depending on the infection of ectoparasites.

The indices of fish infestation in the ponds varied greatly depending on location of growing and month of vegetative season.

An analysis of the fluctuating asymmetry of prussian carp in order to monitor the ecological status of the River Vovk in the city of Derazhnia, Khmelnitsky region.

The article shows a way to promote scientific and technical information at exhibitions through a visual demonstration of the activities and products of institutions. Reflects the problems of the effectiveness of exhibitions for scientific organizations. The aspects of the preparation and holding of the exhibition to improve its effectiveness are given. Examples of the best expositions presented by different countries at international exhibitions are analyzed.

The article reflects the peculiarities of the design of pavilions for participation in exhibitions of scientific organizations. The ways of decorating exhibition stands to improve the efficiency of the exhibition are recommended. The value of the visual and auditory way of attracting customers to the products shown is shown. Analyzed examples of successful design solutions pavilions and errors during the exhibition campaign. Showing photos of the best expositions presented at international exhibitions.