Frangos alimentados com dietas contendo gordura de larvas de inseto em substituição ao óleo de soja

Abstract

In poultry farming, the main source of lipids used in bird nutrition is soybean oil; however, alternative sources are important to increase the range of possibilities for the sector. In this context, black soldier fly larvae fat (BSLF) has become a possibility, as it presents an approximate yield of 40%, being rich in medium-chain fatty acids, such as lauric acid, which exhibits nutritional properties, in addition to antimicrobial functions and modulation of intestinal health. This research aimed to determine the effects of the increasing substitution of soybean oil (SO) by BSLF on parameters of lipid metabolism and the immune system, correlating them with the performance of broiler chickens. Five hundred broiler chickens were used, distributed in a completely randomized design, and five levels of soybean oil substitution by BSLF (0, 25, 50, 75 and 100%) in mash rations were evaluated. Each diet was evaluated in ten replicates with 10 birds each. Water and experimental feed were provided ad libitum from 22 to 38 days of age. The parameters analyzed were zootechnical performance, determined from 22 to 38 days of age, corresponding to feed consumption, weight gain, and feed conversion ratio of the chickens. On the 38th day of age, one chicken from each experimental unit was slaughtered to evaluate carcass and cut yield and to collect samples of pancreas, liver, and pectoralis major muscle, in which pancreatic lipase activity and the concentrations of hepatic fatty acid synthase and muscle carnitine were determined, respectively. In addition, during bleeding, blood aliquots were collected for subsequent quantification of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNF-α) levels. There was no difference (P > 0.05) in the zootechnical performance of the chickens. However, 100% replacement of OS with GBSF resulted in higher (P < 0.05) breast yield. There was no change (P > 0.05) in pancreatic lipase activity, hepatic fatty acid synthase concentration, or serum concentrations of IL-10 and TNF- α (P > 0.05). However, increasing the rate of replacement of OS with GBSF resulted in a linear reduction in carnitine concentration in the chicken breast. It is concluded that increasing replacement of OS with GBSF does not induce modulation of pancreatic lipase and hepatic fatty acid synthase enzymes and does not alter the immune system of chickens. Total replacement of GBSF does not impair zootechnical performance, increases breast yield, and reduces carnitine concentration in the breast.