# Chitinase improves the available energy, amino acids digestibility of black soldier fly and fecal microbiota of growing pigs

## TL;DR

Adding chitinase to black soldier fly diets improves energy and amino acid digestion in pigs and enhances gut health.

## Contribution

Demonstrates that chitinase supplementation enhances energy and amino acid digestibility and modifies fecal microbiota in pigs fed black soldier fly.

## Key findings

- Chitinase increased digestible energy and metabolizable energy of black soldier fly by 2.34 and 1.37 MJ/kg, respectively.
- Chitinase improved apparent ileal digestibility of amino acids like methionine, leucine, and glutamate.
- Chitinase promoted beneficial bacteria and inhibited pathogenic Sarcina in pig fecal microbiota.

## Abstract

The main objective of this study was to determine the energy value and digestibility of amino acids in growing pigs fed black soldier fly (BSF) with chitinase supplementation and its effect on fecal microbiota.

In Exp. 1, eighteen barrows with initial body weight (BW) of 31.6±1.2 kg were randomly assigned to 3 treatments to determine the digestible energy (DE), metabolizable energy (ME), and nutrient digestibility, including the corn-soybean meal basal group, the BSF (14.6%) with 1,500 mg/kg or without chitinase groups. Fresh feces were collected on day 10 of feeding for analysis of microbial diversity. In Exp. 2, six barrows (36.7±4.2 kg BW) with ileal T-cannulas were arranged in a 6×3 Youden square design, pigs were allotted to 3 dietary treatments to determine the digestibility of the amino acids, including the nitrogen-free group, the BSF with or without chitinase groups.

Supplemental chitinase improved (p<0.05) the apparent total tract digestibility (ATTD) of crude protein and dry matter in the BSF diet, improved (p<0.05) the ATTD of crude protein, ether extract and acid detergent fiber in the BSF, and increased the BSF's DE and ME by 2.34 MJ/kg and 1.37 MJ/kg, respectively. Chitinase supplementation improved (p<0.05) the composition of fecal microbiota of growing pigs, promoted (p<0.05) the colonisation of Bacilli, Lactobacillaceae, and Lactobacillales, and inhibited (p<0.05) the proliferation of pathogenic bacteria Sarcina. Adding chitinase enhanced the apparent ileal digestibility and standardized ileal digestibility of most amino acids in BSF, such as methionine, leucine, and glutamate (p<0.05).

Adding chitinase can increase the effective energy value and amino acid ileal digestibility of BSF, regulate the composition of fecal microbiota and improve the intestinal health of growing pigs.