Comparison of nutritive value between intact and defatted black soldier fly larvae for animal feed

Abstract

In this study, the possibility black soldier fly (BSF) larvae as a novel feedstuff for animal was investigated. The objective of this study was to compare the nutritive value between intact and defatted BSF larvae for animal feed by means of chemical composition determination and in vitro rumen fermentation technique. The following treatments were tested: intact BSF (T1), BSF low in lipid by mechanical extraction (T2), BSF low in lipid by chemical extraction (T3), and soybean meal (T4). The samples were subjected to proximate analysis, Van Soest’s fiber fraction and cell wall nitrogen determination. The samples were further incubated in vitro with buffered-rumen fluid in four replicates, represented by two incubation units per replicate, and conducted for 48 h at 39°C. Parameters measured in the in vitro evaluation were total gas production and methane emission at regular time point intervals. Other parameters measured after the incubation were dry matter degradation, organic matter degradation, total volatile fatty acid (VFA), ammonia concentration and pH. Data were tested using analysis of variance (ANOVA) and if there was a significant different at P<0.05 then continued with Duncan’s multiple range test. Results revealed that removal of lipid from BSF larvae either by mechanical or chemical extraction increased dry matter degradability (DMD), organic matter degradability (OMD) and total gas production values as compared to intact BSF (P<0.05). However, these values were still lower than those of soybean meal (P<0.05). Concentrations of ammonia and total VFA were similar across all dietary treatments. It can be concluded that removal of lipid from BSF larvae by either mechanical or chemical extraction improves its utilization in the in vitro rumen fermentation system.