Amino acid digestibility in housefly and black soldier fly prepupae by growing pigs

Abstract

An experiment was conducted with the objectives of determining the coefficient of ileal apparent digestibility (CIAD) and the coefficient of ileal standardized digestibility (CISD) of amino acids (AA) in housefly (HF) and black soldier fly (BSF) prepupae meal by growing pigs. Ten pigs fitted with a T-cannula in the distal ileum with an average initial body weight of 25.05 kg were housed individually in metabolism cages equipped with a feeder and a nipple drinker. The pigs were randomly assigned each to one of two diets formulated to contain 976.7 g/kg of HF or BSF as the sole source of nitrogen. A nitrogen-free (N-free) diet was also formulated to estimate the basal ileal endogenous loss (BEL) of AA. All experimental diets contained 2 g/kg titanium dioxide as an indigestible marker. The daily feed allowance was offered in three equal meals that were fed at 0830, 1400 and 1930 h. Each experimental period lasted for 7 days, the initial 4 d for diet acclimation, followed by 3 d for ileal digesta collection and the digesta samples were collected continuously for 12 h. The CIAD of all AA for HF and BSF are more than 0.726 and 0.641, respectively. The values for the CISD of all AA range from 0.870 to 1.608 and from 0.767 to 1.177 for HF and BSF, respectively. Moreover, the values for the CIAD of all AA in HF are greater (P < 0.05) than in BSF. The dispensable AA account for the most proportion of the endogenous fraction and the BEL of proline is the greatest. The values for the CISD of all AA except methionine and cysteine in HF are also greater (P < 0.05) than in BSF. It is concluded that the digestibility of all AA in HF is greater than in BSF in pig.