There is examined the current biological state of fish populations, which consist the base of commercial harvest in the Kakhovka reservoir. There are analyzed basic trends, which characte- rize the change of age structure of exploited populations and repartition of catches by mesh size in fishing gears. There are assessed dynamics of commercial stocks recruitment and formation of fish base for commercial harvest. There are proposed optimization ways for commercial exploita- tion of the Kakhovka reservoir.
There are determined and analyzed basic indices, which characterize reaction of bream popu- lation of the Kiev reservoir on effect of commercial harvest at current level of its organization. There are determined parameters of commercial load, which have to be regulated for rational exploitation of bream population.
There has been analyzed the current state of roach commercial stock of the Kanev reservoir. With the aid of cohort analysis, there were estimated fishing mortality, possible number, and bio- mass of commercial stock of this species for 2005–2006. There were modelled yields per recruits of silver bream using a Thompson and Bell type model. According to results, the roach commercial stock of the Kanev reservoir is exploited irrationally.
Influencing of hydrological conditions on morphological indications of roach from different reservoirs was considered. It was concluded that significant determination of some of plastic indications or their groups for typical river or lake roach’s forms is not possible.
There was studied the state of spawning grounds of the Kremenchuk reservoir. There are presented results of studies on determination of areas of shallow water sites of the Kremenchuk reservoir, which are suitable for reproduction of fish and their juveniles. It was found that major spawning grounds were upper and lower parts of the reservoir.
Resulted taking on specific composition of fish of the Kachovka storage pool in a period to close of flow of Dnepr and on the modern stage. It is set that for period of existence of storage pool specific composition of fish changed substantially. Presently clupeonella and silver carps come forward the most numerous users of plankton of the Kachovka storage pool. The changes of their age structure are in this connection analysed during 1992–2005 it is Set that statistical information on the issue of silver carps in a storage pool, during the last years does not answer reality.
Nutrition spectrum and bolus composition of bream of the Kremenchuk reservoir during it’s the most intensive feeding period was studied in comporative-temporal aspect with the aid. There were revealed the dominating role of preferred food (larva and pupa of Chironomidae) and decrease of detritus and sand content in fish bolus. This fact allows ascertaining that there are favorable conditions for bream fattening in Kremenchuk reservoir.
There was examined the change of basic biological indices of perch population of the Dniester River reservoir for a long period. There were determined and analyzed factors, which defined the dynamics of its number and particularities of perch distribution over the reservoir area. There were proposed measures for optimization of ichthyofauna structure of the Dniester River reservoir as a fisheries water body.
Results of investigations of levels of radioactive pollution abiotic and biotic components of hydroecosystems of river Desna in limits of Ukraine are shown.
The method is used for finding optimal ways to rehabilitate natural water objects with mini- mum costs expenditure. Under present conditions the most effective is the minimum program: the and reservation of local fish restoring sites, the recreation of natural spawning and hibernation pockets, the arrangement of water protecting strips and their physical introduction into reality, the use of natural relief elements for restoring fish and post treatment of waste waters, the fight against poachers.
Content of chlorine organic pesticides in fish of the Dnieper river, Dniepers reservoirs and Dnieper–Bug Estuaries (on our and literature data) are presented in this articles.
The article contains results of larvae ongrowing and black carp fingerlings growing in polycul- ture with grass carp. Optimum indexes are got at larvae ongrowing with the density 100 thousand fish/ha duration 20 days. Maximal fish-productivity and survival of fingerlings is attained at growing of them from ongrown fry with a density 20 thousand fish/ha.
It is investigated series of physiological-biochemical parameters of a reed mace platyphyllous and yellow water lilies on a background anthropogenic influence on an ecosystem of separate sections r. Ros. The obtained data allow judging a level of ecological trouble of the polluted sec- tions of the river.
The sexual products of paddlefish (Polyodon spathula (Walbaum)) females in their first year of maturation were of low quality. The highest reproductive indices were observed in broodfish that had been used repeatedly. Testing different hormonal substances indicated that the best paddlefish , arti- ficial reproduction was observed with the application of LHRH-A to stimulate female maturation. The method of obtaining mature oocytes by puncturing the female abdominal wall near the genital opening was noted to be very efficient. There were conducted successful experiments with low-temperature preservation of paddlefish sperm. Survival rate of defrosted sperm cells was not less than 77%.
In the article the questions of efficiency of commodity fish growing in ponds in different technologies, quality and production cost price are expounded. It is determined, that growing of two-years old carp hybrids at the density of one-years about 2100–2200 fish/hа provides the receipt of two-years with individual weight 820–1050 g and fish-productivity 1040–1297 kg/ha.
Demonstrated is effectiveness of growing up carp and silver carp larvae in spawning ponds with limited water supply (10–15 litres per min) density level is not more than 1–2 mln. larvae per hectare; determined is possibility of using plastic traps to control growth intensity of larvae, their survival and influence of feeding base (zooplankton).
Resulted results of growing of 0+ and 1+ grass carp in a monoculture at the use of forages of vegetable origin in the ponds of stock company “khmel’nytskrybgosp” in 2007.
The characteristic of scaleless of a common carp of the Transkarpatian plant line of the second generation of selection by exterior and reproductive indexes is presented. It is shown that param- eters of a constitution of breeders F2 in comparison with the Lyubin frame carp and reproductive indexes — in comparison with the carp Frasinet are considerably improved.
Results of research hematological indicators of young-of-the-years and yearlings carp-like fishes are resulted. It is established, that change of those or other parameters of internal of yearlings testifies to certain changes of a physiological condition young and can be considered as a specific signal for working out of corresponding preventive actions and optimization of technological parameters at the organization of process of cultivation two-year-olds.
It was shown that under influencing of limphosarcomatose the activity of lactatdehydrogenase and alkaline phosphatase in liver and spleen of pikes is considerably increased.
In work the results of selection and accumulation of bakteriofagiv are presented from the cultures of microorganisms which were selected in the laboratory of ikhtiopatologii of UAAN from the different types of fishes with the signs of disease and from a navkolishn’go environment. Research of their properties and selection of lizogennikh mutations with the purpose of their use as a biological method, for the fight of freshwater fishes bacterial illnesses.
The resulted is given theoretical ground of alternative method of of microtome of tissues of hyd- robionts. Shown expedience of the complex use of angular method of cutting and arched reception of histological objects. The question of subsequent introduction of arched microtome is affected in research practice with the purpose of study of features of histological structure of fishes.
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