Comparative Fish Reproduction Conditions of Volgograd Reservoir Near Villages of Akhmat and Zolotoe Russia

2021 ◽  
Vol 14 (2) ◽  
pp. 866-870
Author(s):  
Dmitry Iu. Tiulin
Author(s):  
Dmitry Yurievich Tyulin ◽  
Aleksey Alekseevich Vasiliev ◽  
Anastasiya Andreevna Anuryeva ◽  
Roman Romanovich Radionov ◽  
Anastasiya Romanovna Plotko ◽  
...  

The main factor affecting the success of the reproduction of limnophilic fish is the level height and duration of the spring flood with uniform heating of the water. However, the efficiency of fish reproduction also depends on other factors, for example, on the development of the food supply for early juveniles. In 2020, in the water area of the Volgograd reservoir near the villages Akhmat and Zolotoye, according to the results of catches of fry net, developed very unfavorable conditions for the reproduction of commercial fish. The values of production indicators (net primary production and the rate of respiration of the plankton community) in 2020 turned out to be minimal. The dynamics of the abundance, and especially the biomass of benthic invertebrate communities, turned out to be very similar for both water areas in 2018 and very different in 2020. In terms of abundance, among benthic invertebrate communities, in the water area near the village Zolotoye in July 2020, was dominated by oligochaetes and chironomids, and oligochaetes in terms of biomass. At the station near the village Akhmat in July was dominated by chironomids in terms of numbers, and oligochaetes in terms of biomass. In August and September, both in terms of abundance and biomass, oligochaetes dominated in both water areas. There is a correlation between the state of production processes and the state of benthic invertebrate communities in the reservoir. However, the efficiency of fish reproduction correlates, first of all, with the level and temperature regimes of the reservoir during the spawning and feeding period. The decrease in the proportion of underyearlings of crucian carp and perch feeding on benthic invertebrate communities in the catch of fry net in 2020 may be due to both an unfavorable level regime and a drop in the feeding capacity of the water areas.


Author(s):  
S. Assylbekova ◽  
N. Badryzlova ◽  
L. Kushnikova

The article presents the results of the first research on artificial reproduction in industrial conditions of the endemic, narrow-areal subspecies of Brachymystax lenok Savinovi, which lives in lake Markakol, East Kazakhstan region. The indicators of the heat sum characteristic for each stage of development, the rate of development and growth of the Markakolsky lenok from the moment of pre-breeding to late juveniles are described. To develop technological approaches for artificial fish reproduction, one of the most important points is to determine the optimal conditions for each stage and assess the risks (loss of fish products). At the stage of insemination and transportation of eggs to the place of incubation, the loss was 50 %. The largest losses of fish products were registered during the incubation stage. The most painlessly passed the period of holding and lifting on the float, where the loss was only 3 %. When growing pre-larvae and larvae in the pool, the daily waste did not exceed 1 %. Small-sized animals that were unable to adapt to artificial feeds fell into the waste. Losses during this period amounted to 15 % of the previous stage. In General, the yield of juveniles from the moment of fertilization to the end of the experiment was 16 %. The crucial factor in the development and growth of Lenok Markakolosky is the temperature regime. For the period of embryonic development, the most favorable water temperature is 7–8 °C. From the moment of hatching, the water temperature must be increased to 10–12 °C, and the optimal temperature for the cage growing of fingerlings varies from 12 to 14 °C.


2010 ◽  
Vol 45 (2) ◽  
pp. 187-200 ◽  
Author(s):  
Joanne L. Parrott ◽  
L. Mark Hewitt ◽  
Tibor G. Kovacs ◽  
Deborah L. MacLatchy ◽  
Pierre H. Martel ◽  
...  

Abstract To evaluate currently available bioassays for their use in investigating the causes of pulp and paper mill effluent effects on fish reproduction, the responses of wild white sucker (Catostomus commersoni) collected from the receiving environment at the bleached kraft mill at La Tuque, Quebec, were compared with responses of fathead minnow (Pimephales promelas) exposed to effluent in a laboratory lifecycle test. White sucker collected at effluent exposed sites had increased liver size but none of the reproductive effects that had been documented in earlier field studies at this site. Exposure to 1, 3, 10, 30, and 100% bleached kraft mill effluent (BKME) in the lab led to significantly decreased length, but increased weight and liver size in male fathead minnow. Female length was also decreased and liver size was increased at high effluent exposures. Most effluent concentrations (1 to 30%) significantly increased egg production compared with controls. The fathead minnow lifecycle assay mirrored the effects seen in wild fish captured downstream of the BKME discharge. These results will be used to select short-term fish tests for investigating the causes of and solutions to the effects of mill effluents on fish reproduction.


2008 ◽  
Vol 43 (2-3) ◽  
pp. 161-171 ◽  
Author(s):  
Pierre Martel ◽  
Tibor Kovacs ◽  
Virginie Bérubé

Abstract Pulp and paper mill effluents have been reported to cause changes in reproductive indicators of fish in laboratory and field studies. These changes include reduced egg production and gonad size, and altered hormone levels and expression of secondary sex characteristics. We examined the performance of biotreatment plants for their potential in abating effects of pulp and paper mill effluents on fish reproduction under laboratory conditions. A bleached kraft mill effluent (BKME) treated in an aerated lagoon and a thermomechanical pulp mill effluent (TMPE) treated by aerobic sludge in a sequential batch reactor were selected for study. Mature fathead minnows (Pimephales promelas) were exposed to effluents before and after biotreatment under continuous renewal conditions for 21 days. Egg production was monitored daily, while morphometric parameters (length, weight, gonad size), secondary sexual characteristics, and steroid hormone and vitellogenin levels were measured at the end of the effluent exposure. The effluent from both mills before biotreatment impaired the reproductive capacity of minnows (egg production) at concentrations of 10 and 20% vol/vol, but not at 2% vol/vol. Exposure to biotreated effluents from both mills at concentrations of 2, 10, 20, and 40% vol/vol caused no significant differences in overall reproductive capacity of minnows as compared with controls. These results indicate that biotreatment can significantly improve the quality of a BKME and an effluent from a TMP mill with respect to the reproductive capacity of fish as determined in laboratory tests.


2021 ◽  
Vol 22 (12) ◽  
pp. 6478
Author(s):  
Lian Hollander-Cohen ◽  
Matan Golan ◽  
Berta Levavi-Sivan

From mammals to fish, reproduction is driven by luteinizing hormone (LH) and follicle-stimulating hormone (FSH) temporally secreted from the pituitary gland. Teleost fish are an excellent model for addressing the unique regulation and function of each gonadotropin cell since, unlike mammals, they synthesize and secrete LH and FSH from distinct cells. Only very distant vertebrate classes (such as fish and birds) demonstrate the mono-hormonal strategy, suggesting a potential convergent evolution. Cell-specific transcriptome analysis of double-labeled transgenic tilapia expressing GFP and RFP in LH or FSH cells, respectively, yielded genes specifically enriched in each cell type, revealing differences in hormone regulation, receptor expression, cell signaling, and electrical properties. Each cell type expresses a unique GPCR signature that reveals the direct regulation of metabolic and homeostatic hormones. Comparing these novel transcriptomes to that of rat gonadotrophs revealed conserved genes that might specifically contribute to each gonadotropin activity in mammals, suggesting conserved mechanisms controlling the differential regulation of gonadotropins in vertebrates.


Author(s):  
S. Milla ◽  
N. Wang ◽  
S.N.M. Mandiki ◽  
P. Kestemont

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