Conservation of the Sturgeon Fish in Lower Volga

Author(s):  
S. A. Maltsev
Keyword(s):  
Author(s):  
Angelika Vyachislavovna Kovaleva ◽  
Petr Petrovich Geraskin ◽  
Vadim Alekseevich Grigoriev ◽  
Gennadiy Fedorovich Metallov ◽  
Elena Nikolaevna Ponomareva

Physiological state of the stellate sturgeon female species ( Acipenser stellatus ) caught in spring in the fishing area in the Lower Volga delta and the female species farmed at the Bertyulckiy and Lebyahzje sturgeon fish-factories in the Astrakhan region were evaluated by biochemical parameters of blood taken in fish after hypophysial injection. At each sturgeon fish-factories there were revealed 2 groups of fish with different biochemical status. At the Bertyulskiy sturgeon fish-factory in the first group blood values were normal, in the second group the level of serum protein, β-lipoproteids, cholesterol and hemoglobin in blood was lower by 1.5, 4.3, 1.7 and by 1.2 times, correspondingly. At the Lebyahzje sturgeon fish-factory in female species of one group the level of serum protein, β-lipoproteids and cholesterol was even lower: in 1.8, 2.5 and 2.3 times. In the group of stellate sturgeon females with a lower concentration of biochemical components in blood there was revealed excessive total bacterial contamination: at the Bertyulskiy fish-factory - in 3 times, at the Lebyahzje - in 8 times. The results obtained allow to suggest the dependency of the bacterial contamination level on physiological status of fish. Study of stellate sturgeon females caught in spring in the lower reaches of the Volga and females used for fish breeding at the sturgeon fish-factory showed that under equal physiological status the level of total contamination of fish was much higher at the fish-factory, i.e. fish in natural habitats were more resistant to infection. The comparative analysis of physiological status of stellate sturgeon males and females caught in spring in the lower Volga and having similar physiological status revealed, that females during spawning run had higher level of total contamination. The study results can be used for the diagnosis and correction of the physiological state of sturgeons cultivated in ponds with closed water supply systems with the application of artificial feed.


Author(s):  
Elena Nikolaevna Ponomareva ◽  
Maria Mikhailovna Belaya ◽  
Alexandra Andrianovna Krasilnikova ◽  
Alexander Nickolaevich Nevalennyy

The research on the sterlet roe artificial insemination using cryopreserved sperm was carried out in the research base of the RAS Southern Scientific Centre (the Rostov region). Reproductive cells (including cryopreserved cells), larvae, sterlet fry ( Acipenser ruthenus Linnaeus, 1758) were taken as an object of research. A half of the roe (1.7 kg) taken from female starlet was inseminated by native sperm (control group); another half was inseminated by defrosted sperm of two males, which was stored in liquid nitrogen at -196ºC during 3 years (pilot group). Incubation lasted 5 days at water temperature 14.5-18.2ºC, with daily fluctuations of temperature 1.9ºC. Roe insemination in the control group made 90%, in the pilot group - 70%. Roe embryonic growth in the control group was faster, but embryogenesis duration in the pilot group met the standard time limits. Hatching prolarvae in the control group started one hour earlier, than in the pilot group; it made 75% and 60% of all incubated roe, correspondingly. Waste during the period of larvae maturing before they pass to mixed feeding was negligible - 2% in the control group and 3.4% in the pilot group. According to the test results, "open field" of reactivity of the central nervous system in the pilot group fry didn’t change from the control group fry, but more active response to stimuli was noted in the pilot group, which is very important for fry adaptation to the conditions in natural water basins. It was established that sterlet offspring obtained with use of defrosted sexual cells does not differ from the offspring obtained using native sperm and has higher morphometric characteristics. The test results prove the possibility and practicability of using sexual cells stored in liquid nitrogen for artificial restoration and formation of sturgeon fish broodstocks.


Author(s):  
E. A. Vertikova ◽  

In a competitive variety trial, promising selection lines of sugar sorghum were studied in the Lower Volga region. Based on a set of signs, the best lines were identified, which are recommended for transfer to the State Variety Testing. Breeding lines, which are distinguished by high values of commercially valuable traits, can be used in planned crosses to create highly productive varieties and hybrids of sugar sorghum.


Author(s):  
I. V. KORNIENKO ◽  
◽  
T.G. FALEEVA ◽  
G.G. MATISHOV ◽  
◽  
...  
Keyword(s):  

2015 ◽  
pp. 26-37
Author(s):  
V. B. Golub ◽  
V. V. Bondareva ◽  
A. N. Sorokin ◽  
L. F. Nikolaychuk

Plant communities with reed domination (Phragmites australis agg.) occupy the large areas in the Lower Volga Valley and especially in the river delta. We have set the task to reveal the diversity of these communities in the Lower Volga Valley. For this purpose, we applied the database that is registered in the Global Index of Vegetation-Plot Databases (GIVD) under the EU-RU–002 index (http://www.givd.info/) and includes 14871 relevés made during the period from 1924 to 2013. Communities with the dominance of reed were defined as such, if the coverage of this plant was more than 50 %. We have found 375 such relevés in the database. At first, one basal community, 3 associations and 3 subassociations with domination of Phragmites australis agg. were distinguished in the Lower Volga Valley. All processing and analysis of relevés were performed using the software package JUICE 7.0. (Tichý, 2002). The «Cocktail» method was applied to establish the sociological groups that indicate environmental conditions (Bruelheide, 2000). The expert system for selection from the database of relevés by means of these groups was created. It is allowed us to ascribe relevés to earlier distinguished associations, subassociations and basal community. 171 relevés have been identified by the expert system and they were assigned to association, subassociation or the basal community. 204 relevés were not referred to any association, subassociation or the basal community. We wanted to answer the question: are there among these 204 relevés, which could be interpreted as the new syntaxa, giving them the proper ecological characteristics? For this purpose, the cluster analysis of 204 relevés has been carried out. The optimal level of clustering was determined by calculating the index of “crispness of classification” (Botta-Dukát et al., 2005). The greatest “crispness of classification” was reached at allocation of 13 clusters. Consideration of the floristic composition of allocated groups had shown that 11 of them were the transitional plant communities among the earlier established syntaxa. Only two clusters were differed in rather original structure that we could explain by the influence of environment factors. We have identified them as new associations Rubio tataricae-Phragmitetum australis and Cynancho acuti-Phragmitetum australis. All associations with the dominance of Phragmites australis agg. distinguished in the Lower Volga Valley were included in the alliance Phragmition communis Koch 1926, order Phragmitetalia communis Koch 1926. In literary sources from the ecological point of view these syntaxa are defined as the wetland communities, which are closely linked to water bodies (Šumberová et al., 2011; Ermakov, 2012). However, in many cases this definition does not correspond to the ecology of plant communities with the dominance of reed in the lower reaches of the Volga River. Ecotops of these communities are flooded for up to 2–3 months in a year and then they dry out. In the autumn, the ground water level can drop to a depth of one meter (Golub et al., 2011). The plant satellites of the reed here are often mesophytic plants such as Rubus caesius, Calamagrostis epigeios, Phalaris arundinacea, Rubia tatarica, Althaea officinalis, and Rumex stenophyllus. Therefore, the inclusion of phytocoenosises with domination of the reed in the lower reaches of the Volga River in the alliance Phragmition communis is rather relative. A correct placement of these plant communities in the system of vegetation syntaxa of the arid areas can be made only if it is based on original data obtained from much bigger territory than the Lower Volga Valley. In future geobotanical studies, it is desirable to divide the aggregation of Phragmites australis agg. into smaller species taxa.


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