Weight growth of different generation of the trout Parasalmo mykiss on Lake Imandra
Journal Title: Вестник МГТУ - Year 2018, Vol 21, Issue 2
Abstract
The averaged indicators of the weight growth of four generations of trout at different temperatures in the time interval of the life cycle from the transfer of larvae to cultivation until the fish reaches a portioned commercial weight of 400 g when the first withdrawal of products for sale takes place have been analyzed. It has been shown that fish of different generations passes into the weight category "goods" sequentially, but after reaching different ages, while there is no direct correlation between the terms "generation formation" – "first withdrawal for sale". According to our data the most intensive weight growth of fish has been noted in the temperature range equal to 8–13 °C. An increase in the water temperature in the cages to 15–18 °C has led to a slowdown, and then to the suspension of the accumulation of fish biomass. In cages operating in the area of Kola NPP heated water trout of April generation gains the commercial weight of 400 g in 7–8 months after landing of larvae for cultivation, November trout – after 15 months. Trout of October and January generation reaches commercial weight at 11 and 9 months, respectively. The stretching of timing of biomass accumulation is most pronounced in the autumn generation of trout. It has been found that the greatest increase in weight per unit body (145.1 mg per day) is provided by the trout of the January biological group, the smallest – by the November trout (75.8 mg per day). The energy reserve of heat allowing for differently derived individuals to reach a commodity weight of 400 g, is in the range from 3 320 to 5 300 degree-day.
Authors and Affiliations
N. R. Kalinina, V. S. Anokhina, P. P. Kravets, O. S. Tyukina
Keywords
Related Articles
- EP ID EP352765
- DOI 10.21443/1560-9278-2018-21-2-270-27
- Views 128
- Downloads 0
Methods of optimizing technologies and recipe of oatmeal cookies
Oat has a special position among grain crops due to its amino acid and fatty acid composition which confirms the value of its use in nutritional aims. The healthy properties of oat are caused by presence in its compositi...
Effect of extraction technology on antioxidant activity of black chokeberry Aronia melanocarpa, cranberries Vaccinium vitis-idaéa, blueberries Vaccinium myrtillus, raspberries Rubus idaeus, cherries Prunus subg. cérasus, black currant Ribes nigrum
Foods rich in antioxidants and antioxidant activity reduce the risk of many diseases. To solve the urgent task of creating an optimal technology for extracting a complex of substances with antioxidant action from fruits...
Sequence of REE-Th-U minerals in the Litsa uranium ore area (the Kola Region)
Mineralogical and petrographic study of REE-Th-U mineralization in rocks of the Litsa uranium ore area has been carried out to detail the sequence of formation of rare-earth, uranium and thorium minerals in rocks. The st...
On the background values of heavy metal content in bottom sediments of the Barents Sea
Based on the long-term data the background content in the number of heavy metals in bottom sediments of the Barents Sea has been estimated. For the purpose to estimate the up-to-date state of the geochemical background t...
Ti-Zr placer mineralization in Neoproterozoic (Upper Riphean) rocks of Kildin Formation and in contemporary beach sands of Sredny and Rybachy Peninsulas, Kola Region
Concentration mechanisms of titanium-zirconium placer mineralization in Neoproterozoic terrigenous rocks of Zemlepakhtinskaya Formation, Kildin Group, and in contemporary beach deposits from Sredny Peninsula and Motka Ca...