Globally the hemp industry production has increased due to the discovery of its nutritional and medicinal benefits. Hemp seed meal (HSM) has shown promise as an alternative protein source in aquaculture feeds due to its sustainable production and nutritional qualities, especially essential and non-essential amino acids. Therefore, the purpose of this digestibility trial was to evaluate HSM as an alternative protein source for largemouth bass ( Micropterus nigricans).
An 11 -week digestibility trial was conducted to investigate the digestibility of two HSM ingredients P30 and P50, with P50 having higher protein content . Four diets were formulated: reference, soybean meal (SBM), P30, and P50. Once a week fecal matter was collected from each of four replicate tanks with 20 fish each through the stripping method. Fecal matter was pooled by tank, dried at 65°C for 24 hours, and stored at 20°C pending chemical analysis. The apparent digestibility coefficient (ADCs) of dry matter, crude protein, phosphorus, and various essential and non-essential amino acids were assessed. The study revealed significantly lower ADCs of crude protein in the reference treatment when compared to the SBM, P30, and P50 diets. Additionally, the P50 diet exhibited significantly higher dry matter ADCs when compared to the reference diet. Further analysis of ADCs for specific amino acids, including Aspartate, Serine, Cysteine, and Arginine, indicated higher ADCs in P50, P30, and SBM diets when compared to the reference diet. This research sheds light on the potential of HEM as a complementary source of nutrients and energy in largemouth bass feeds.