Тваринництво та технології харчових продуктів (Jul 2020)
REARING RAINBOW TROUT JUVENILE FISH OF THIS YEAR AT DIFFERENT LEVELS OF PROTEIN IN FEED STUFFS
Abstract
The article considers the efficacy of using complete feed stuffs with different protein levels for rearing rainbow trout juvenile fish up to 10 g. The purpose of the experiment was to establish the influence of different protein nutrition levels on trout productivity indices. For this purpose, five experimental groups of this year juvenile fish were formed by the method of analogues. The control group of fish consumed feed stuffs with the protein level of 52%. During the comparative period, the experimental fish consumed feed of the control group. In the main period, the level of crude protein in trout feed stuffs ranged from 48 to 56% per 1 kg. As a result of the study performed, it was found that the use of feed stuffs with high protein nutrition (56 %) in feeding of this year trout is accompanied by an increase in their weight by 12.3 % (p < 0.01) and their growth intensity - by 7.1-15.7 % , compared to the analogues who consumed feed with the protein level of 52 %. Reduction of this index to the level of 48% contributes to a probable reduction (p < 0.05) in weight by 11.5 %, and a decrease in growth intensity by 5.8-13.8 %. It has been proved that the cost of feed per 1 kg of weight gain in this year trout, which consumed feed stuff with a protein content of 56 %, was lower by 5.5 %, and with its content at 48 % - by 7.4 % higher, compared to fish that consumed feed stuff with the protein content of 52 %. At the same time, the safety of the experimental fish throughout the experiment was compliant with the normative indices in trout farming and was within the range of 75.2-78.1 %. The analysis of the obtained fish farming results showed that the most economically feasible is rearing of this year trout juvenile fish, who consume feed stuff with the protein nutritional value of 52 %, compared to a decrease or increase in this index to 48 and 56 %, respectively
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