Comparison between organic and inorganic selenium employed in the diet of silver catfish (Rhamdia quelen) fingerlings

Abstract

Selenium is an essential mineral for fish performance. As a nutrient, a concentration of 0.1 to 0.5 mg/kg of diet dry weight is required. The deficiency of it may cause reduction in growth, fertility and antibodies production. The objective of this experiment was to evaluate the effect of diet supplementation with organic and inorganic selenium on the raising of silver catfish (Rhamdia quelen) fingerlings, by comparing the performance of three groups of twenty fingerlings (98.0 ± 12.0 mg), with four replications, and diet supplemented with: 0.3 mg inorganic selenium/kg + 0.3 mg organic selenium/kg (T1); 0.6 mg inorganic selenium/kg (T2); and 0.6 mg organic selenium/kg (T3). After 55 days of cultivation, the group that received diet with only organic selenium supplementation (T3) showed results significantly higher of survival index, final average weight and group uniformity. Thus, it was concluded that organic selenium enhances the performance of silver catfish fingerlings.