Comparative analysis of results of using different food rations in juvenile wels (Silurus glanis) culture

Abstract

Groups of “small” (65 ± 10 g/indiv.) and “large” (110 ± 10 g/indiv.) wels (Silurus glanis) kept for 49 days in cages in cooling water, were fed with semi-extruded feed offered in 5 different doses (1%, 1.5%, 2%, 2.5%, 3%), calculated relatively to the individual metabolic fish weight (W0.8). The feed contained 48.5% crude protein, 14.4% lipids and 20.97 KJ/g gross energy. The experiment showed that, at the water temperature range of 24-28°C, the daily feed demand was identical in both groups of wels and amounted to 2% W0.8, while at 18-23°C it did not exceed 1.5% W0.8.