A completed full-system (scientific-applied) ecological-histophysiological study of the hypothalamo-hypophysial neurosecretory system (HHNS) participation in fish reproduction was established. With the help of light-, electron-microscopy and immunocytochemistry it is established for the first time that at the beginning migrations of passing fish there is a mass accumulation of neurosecretory products in neurohypophysis, which indicates to the inhibition of the normal level of their excretion into the bloodstream. At the same time, they are actively synthesized in the pericarions of the neurosecretory cells in the preoptic nucleus and excretioned into the cavity of the III brain ventricle. Firstly it is a sign of a violation of their basic osmoregulatory function, which should cause a change in habitat. Secondly, the synchronous excretion of neurohormones into the brain’s liquor should cause their neurotropic effect on the CNS behavior centers in the form of a dominant state of arousal in the form of “migration impulse”. At the beginning of spawning, regardless of its season, HHNS also initiates spawning behavior and completes spawning by participating in the body’s protective-adaptive reactions to natural physiological stress. The functional role of the HHNS in fish reproduction is to initiate energy-intensive reproductive processes of migratory and spawning behaviors, and to complete spawning by suppressing the hyperactivity of the target glands, which ensures the body’s transition to energy-saving plastic exchange. The analysis of this key role of HHNS in the integration of fish reproduction by the principle of self-regulation has allowed to define the principles of effective reproduction and cultivation fish management, primarily in the form of finding the most effective impacts on the centers of integration of managed functions or modeling their effects, which should be carried out in natural periods of functional lability of the body. A constructive working scheme neuroendocrine integration of fish reproduction has been presented and the possibility of applying method of comparative analysis to further develop the system management biotechnics of fish populations reproduction is considered.

The participation of the hypothalamo-hypophysial neurosecretory system (HHNS) in fish reproduction was shown by histomorphological and electronic microscopical studies with the use of quantitative morphometry. The activation of HHNS at the beginning of spawning and the following decrease of its functional activity was revealed in all studied one-time spawning fish species independently of the spawning season (based on spring-, autumn- and winter-spawning genera: Acipenser, Oncorhynchus, and Lota respectively). The diphasic reaction of HHNS corresponding to stages of “an alarm and resistance to stress”, is considered to be the reflection of its participation in protective-adaptive reactions of an organism to a physiological stress. In monocyclic species, right after spawning, there becomes the blockade of neurohormone releasing function from neurohypophysis corresponding to supernatural inhibition of system at disstress. At the beginning of spawning nonapeptide neurohormones (NpNh) of HHNS initiate spawning behavior and the appearance of “mating attire” by exposure to the central nervous system, pituitary gland and complex visceral organs. Then they promote ovulation and spermiation by stimulating the contraction of the smooth muscles of gonad. By the end of reproduction, they participate in the implementation of the body’s adaptations, aimed at overcoming physiological stress-spawning. Maintaining the body’s metabolic equilibrium is ensured by the pronounced anti-gonadotropic NpNh effect by inhibiting the gonadoliberin secretion and stimulating at the same time its antagonist – adrenocorticotropin secretion, as well as their direct effect on endocrine and generative gonad’s functions. This effect is crucial for the normalization of the physiological body state after spawning, as it allows to radically affect the nature of metabolic processes, by “switching” them from generative to plastic metabolism. A constructive working scheme of neuroendocrine regulation fish reproduction – its initiation (stimulating neurohormonal effect) and completion (inhibitory effect) by the self-regulation principle is presented. The important HHNS functional role in the integration of fish reproduction and the intended mechanisms for its participation in spawning migrations are discussed.

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With a view to year-round valuable fish farming a control system terming their breeding and growth, protected by USSR inventor’s certificates and Russian inventor’s patents, was developed. The management principle is fish contents in “critical” salinity along with the simultaneous thresholds “signal” factors (temperature and light) and subsequently obtaining offspring and juveniles in complex of optimal ecological conditions. For the implementation of the proposed industrial biotechnology and year-round fish farming a new installation of water recycling system (WRS) hatcheries and farms was developed by means of the underground conditioning of fish cultivation medium. Their essence is that fish farm water supply systems are additionally provided by underground, or in a half in ground large volume tank-sump tanks. Such WRC, being isolated from climate conditions, allow to conserve and use natural seasonal water resources and first consensually resolve earlier alternative volume-dependent energy problem (requiring lower volumes of water) and water purification (requiring its increasing) in septic tank-sump tanks. The basic principle of their operation is filling one tank-conditioner by “cold” water and the other by “warm” at the appropriate seasons and by additional water supply fish farm systems water circulation. Techno-economic calculation shows, that with the increasing volume of such water air conditioning heat transfer will be proportionally reduced, but productivity increases and reduces its system specific cost while maximizing reliability.

According to presently used biotechnics of salmon farm reproduction, producers are withdrawn (fishing out) from spawning (fish spawning grounds), and the survival rate of one-year-old farmed juveniles in nature (in the form of “spawning return”) is half of the standard. To exclude these most important biotech imperfections, a new biotechnological approach based on the identification and use of species potencies of reproduction, survival and growth in an adequate species-specific complex of optimal habitat conditions are developing. The purpose of our full-system research is to develop effective biotechnics for the artificial reproduction of salmon fish populations in the North-West. To refine the previously developed basic full-system method of reproduction of salmon and sturgeon fish populations to the possibility of its industrial use is the main task of the work. The new “Method for production offspring of sturgeon and Atlantic salmon in seawater” includes the maintenance of brood-stock and the production of offspring of migratory fish in a wide range of salinity of the brood pond. To do this, at the onset of spawning temperatures, producers are sorted according to the degree of readiness for spawning and physiological (hormonal) stimulation of the mature producers gonads maturation are carried out with a natural hormonal preparation — an isolated anterior pituitary lobe, in established species temperature-dependent doses. And immature producers are subjected to environmental (ecological) stimulation of maturation by a periodic influx of fresh water and, upon reaching readiness for spawning, they are stimulated by preparate of the isolated anterior pituitary lobe. The method provides the efficiency increase of natural and artificial reproduction of migratory fish by expanding the possibilities of obtaining offspring from producers in the marine habitat.