Влияние температуры воды на структуру расхода обменной энергии у рыб

Abstract

The paper gives the analysis of the influence of water temperature on the structure of metabolic energy in carp and silver carp of different age groups. The thermophilic species 
 of carp and spotted silver carp cultivated in the polyculture with natural nutritive base served as the material for a research conducted in a hatchery “Individual Enterprise of Alekseeva M. V.” in Kuzovatovsky district of the Ulyanovsk region. Analysis of fish metabolic energy was made using the mean of live weight of yearlings and two-year-old species of carp and silver carp. As a result, there have been obtained the values of the metabolic energy in fingerlings and two-year-old species of carp and silver carp at different ranges of water temperature. Metabolism in carp and silver carp species being representatives of thermophilic fish is most effective at temperatures within +18-+30°С. The study showed that a decrease in water temperature by 5°C (from 20 to 15°C) causes a decrease in food activity, the daily feed intake of yearlings and two-year-old species of carp and silver carp decreased by 35-40%. Expense for the basal metabolism and growth did not change. Metabolic energy was used by 10.8-13,3.0 kJ less. Also, yearlings and two-year-old species of carp and silver carp spent less energy on motion activity than in the warmer water. Thus, under a decrease in the water temperature in the pond the costs of maintaining thermal homeostasis in fish increased, while the costs of basal metabolism, on the contrary, decreased. Situation is quite different when the water is warmed up.