Farinha de black soldier fly (Hermetia illucens) em dietas para larvas de tilápia

Abstract

Insect meal consists of an important alternative source of protein in aquaculture, due to its nutritional value, in addition to presenting an ecologically sustainable production. The present study aims to evaluate the effect of replacing fish meal (FM) protein with black soldier fly (BSF) (Hermetia illucens) meal protein for tilapia sp. The experiment was carried out at the Fish Farming Station of the Federal University of Lavras. The test was conducted in a randomized block design, with four treatments: control diet (FM) and BSF 33 flour; 66 and 100% and eight repetitions. For this, 960 tilapia larvae were distributed in 32 glass aquariums with a capacity of 15 L, at a density of 30 fish/aquarium, kept in a closed system of water recirculation. The animals were fed eight times a day, with an interval of one hour between meals, for a period of 30 days, and the amount of feed provided was weekly standardized according to biomass. At the end of the experiment, six animals per aquarium were euthanized by immersion in water and ice. Whole fish samples were collected for enzymatic activity analysis and histological analysis. The data obtained were submitted to ANOVA analysis of variance and the differences between the averages determined by applying the Tukey test, with a significance level of 5% (P<0.05). The results of this work indicated that there was a significant difference (P<0.05) between treatments. The total replacement of FM by BSF flour led to higher enzymatic activity of alkaline phosphatase (39.26 μmol), amylase (756.11 μmol) and chymotrypsin (472.57 μmol) when compared to larvae that consumed control diet (FM) and diet with lower replacement levels (33 and 66%). As for the histological analysis, the total replacement of FM by BSF flour led to a reduction in total height (163.03 μm), villus height (144.50 μm) and lamina propria height (108.20 μm) when compared to larvae that consumed FM and diet with lower substitution levels (33 and 66%). it was possible to conclude that it is feasible to replace fish meal protein with protein from black soldier fly (Hermetia illucens) for tilapia larvae, at levels of up to 66% without causing changes in intestinal villi and increasing enzymatic activity.