Apparent nutrient digestibility, metabolizable energy and apparent ileal amino acid digestibility of commercial partially defatted Hermetia illucens meal for laying hens

Abstract

Abstract A digestibility study with laying hens was carried out to determine the nutritional value of a commercial and representative (batch to batch variance adjusted) insect meal based on Hermetia illucens (HI) larvae, (from black soldier fly) which was the objective in this study. A basal diet (BD; CP 15%), formulated and fed as such and an experimental diet (HD; CP 21%) consisting of BD with inclusion of 18% of the HI meal were used in the study. The BD and HD were fed to eight and six replicate metabolic cages, respectively, with eight Dekalb White laying hens each from 25 to 27 weeks of age. Diets (pelleted with TiO2 as marker) and water were available for ad libitum intake. Excreta was collected during the last three days to determine AMEn and apparent total tract faecal nutrient digestibility coefficients (ATTDC). Distal ileal content was collected at the last day of the experiment to determine apparent ileal amino acids digestibility of diets and HI meal. Using table values for endogenous losses standardised ileal amino acids digestibility coefficient (SIDC) of HI meal were also calculated. Analysed nutrients (g/kg) in HI meal were: 47 moisture, 529 crude protein, 71 ash, 135 fat and thus 218 was calculated as carbohydrates. Determined AME AMEn for HI meal was 3,846 kcal/kg dry matter (DM) and AMEn was 3,498 3,671 kcal/kg DM and ATTDC AFD for crude protein, crude fat and carbohydrates was 0.830, 0.940 and 0.680, respectively. Average SID coefficient for the 18 amino acids was 0.861 86.1%. Among indispensable amino acids SIDC ranged from 0.790% for threonine to 0.950% for phenylalanine and was 0.840% for lysine. These findings highlight that HI meal is an interesting alternative protein source for soybean meal (SBM). Besides market prices and availability, demands for more sustainable poultry production will determine the use of HI meals as alternative for SBM in poultry diets in the near future, especially in regions where SBM is imported from overseas.