Assessment of the effect of activated carbon on the body of rainbow trout (Oncorhynchus mykiss)

The purpose of this study was to evaluate the effectiveness of using activated charcoal at dosages of 1, 2, and 3 g/kg of feed in the feeding of one-year-old rainbow trout ( Oncorhynchus mykiss ). The study was conducted in a cage farm. The fish were divided into four groups: a control group and three experimental groups. The results showed that 2 g/kg of activated charcoal in the feed was the best dosage for increasing live weight by 19.6% (p≤0.01) and the energy value of the product by 24.8%, while the feed conversion ratio decreased by 12.5%. There was a significant decrease in several toxic elements, such as Cd, As, Sr, and Al, while Pb increased. The use of activated charcoal at dosages of 1 and 3 g/kg of feed did not lead to changes in fish farming and biological indicators, except for an increase in energy value (by 22.6–23.5 %), while the feed coefficient increased to 15.8 %. However, in all experimental groups, there was a noticeable decrease in a number of amino acids in the fish muscle tissue, including the essential amino acids leucine and isoleucine.