Farinha de larvas da mosca soldado-negro (Hermetia illucens) na dieta de alevinos de Jundiá (Rhamdia quelen)

Abstract

Black soldier fly (Hermetia illucens) larvae meal (BSLF) has stood out as an alternative ingredient in fish diets due to its high protein, lipid, and mineral content. However, there are still no studies with native Brazilian species, such as the jundiá (Rhamdia quelen). This thesis is structured in two chapters. Chapter I evaluates the zootechnical performance and body composition of jundiá fry fed diets containing levels of BSLF meal, and Chapter II verifies the effects of inclusion on the biochemical and hematological profile, as well as intestinal and hepatic histological alterations. For the collection of experimental data for both chapters, 240 fry (1.94 ± 0.02 g) were used, distributed in a water recirculation system with 20 experimental units, with individual oxygenation, interconnected to each other and to a mechanical filter and a biological filter. The experiment was conducted in a completely randomized design with five treatments (diets with 0%, 1.5%, 3.0%, 4.5%, and 6.0% inclusion of BSLF) and four replicates. The fish were fed for 87 days. To evaluate the productive performance of the animals, at the end of the experiment all animals were fasted for 24 hours, anesthetized, weighed, and measured. Five animals from each experimental unit were then used to determine body composition (moisture, protein, ether extract, and mineral matter). Blood biochemical, hematological, and histological parameters were also evaluated in the same fish. The results were subjected to analysis of variance (One-Way ANOVA), followed by Tukey's multiple mean comparison test, with a probability level of 5%. The results of the experiment demonstrated that the inclusion of 3% BSLF provided greater final weight, weight gain, daily weight gain, body size, better condition factor and specific growth rate, as well as a higher hepatosomatic index (P<0.05), compared to fish that received the diet without the inclusion of the flour and those that received the diet containing the highest level of inclusion, equaling the other treatments. The parameters of feed conversion, feed efficiency and survival were not influenced (P>0.05) by the inclusion of BSLF in the fish diet, as well as the body chemical composition. Therefore, the inclusion of up to 3% BSLF as an alternative ingredient in the formulation of diets for jundiá fry is recommended. Regarding the biochemical and hematological profile of the animals' blood, the results obtained showed that the inclusion of BSLF flour does not alter the analyzed parameters, indicating stability in the evaluated indices (P>0.05). In the histological evaluation, the length of the intestinal villi remained stable between treatments, suggesting an absence of morphofunctional impairments. Regarding the liver, mild to moderate alterations were observed, including fatty degeneration and discrete nonspecific inflammatory infiltrates. Therefore, the inclusion of up to 6% black soldier fly larvae meal in the diet of jundiá fry proved to be safe, not compromising the metabolic, hematological health or histological integrity of the species. In general, the inclusion of up to 3% of BSLF in the diets of jundiá fry is recommended for better productive performance, guaranteeing the metabolic, hematological health and intestinal histological integrity of the species.