Evaluation of different inclusion levels of a novel ingredient combination on growth performance, nutrient utilization and gene expression in Penaeus vannamei

Nowadays, due to the high demand and cost of conventional ingredients like fishmeal, as well as the need to create nutritionally effective diets for shrimp, alternative ingredients are being actively explored. In this study, novel feed ingredients were selected, and an eight-week feeding trial was carried out to assess the impact of diets formulated with different inclusion levels of novel ingredient combination. The study evaluated the growth performance, digestibility, digestive enzyme activity, and IGF-I and IGF-II gene expression in Penaeus vannamei. Four isonitrogenous (crude protein, 36%), isolipidic (crude fat, 6%), and isoenergetic (gross energy, 16 MJ/Kg) diets were formulated. The ingredients, namely poultry byproduct meal (PBM), insect meal (IM), rapeseed meal (RM), peanut meal (PM), fish waste (FW) and single cell protein (SCP) were incorporated into the diets at 24.82% (Diet 1), 28.82% (Diet 2), 32.82% (Diet 3) and 36.82% (Diet 4). A total of 420 shrimps (average initial weight of 1 g) were distributed into 12 tanks (35 shrimp per tank). The experimental diets were fed to triplicate groups of P. vannamei three times a day until satiation for 60 days. Among the dietary groups, significantly (p < 0.05) higher weight gain, final weight, ADG and SGR were observed in shrimp fed with Diet 3 and 4 than other diets. FCR, PER and survival remain unaffected with no significant difference (p > 0.05). In hepatopancreas, digestive enzyme such as lipase shows significantly higher activity in shrimp fed with Diet 4, which was not different from Diet 3 (p < 0.05). In the intestine, significantly higher amylase activity was found in Diets 3 and 4, which was not different from Diet 1. Likewise, lipase activity was significantly higher in Diets 3 and 4 in the intestine (p < 0.05). No significant difference (p > 0.05) was found in whole-body proximate composition, gene expression activities and apparent digestibility coefficients of shrimp fed with varying inclusion levels of novel ingredient combination. The results of this study revealed that the growth performance and nutrient utilization of P. vannamei remain unaffected, even with the inclusion of novel ingredient combination at a level of 36.82%. Therefore, this research suggests that the potential of the novel ingredient combination as a sustainable and cost-effective alternative to conventional, increasingly expensive ingredients without adverse effects. Even at maximum inclusion levels, the combination proved beneficial for shrimp, making it a promising solution for future feed formulations.