Exogenous dietary enzyme formulations improve growth performance of broiler chickens fed a low-energy diet targeting the intestinal nutrient transporter genes.

Diminishing the cost of broiler chicken diet is a critical issue in the poultry industry. Numerous studies were performed to achieve this pivotal objective by diet supplementation with alternative feed additives. In the current study, low-energy broiler rations were supplemented with different commercial multienzyme formulations to minimize the cost, and increase the digestibility and absorption of the digested macronutrients. Cobb Avian 48 broiler chicks (mixed sex, 1-d-old, n = 3120) were randomly allocated into six groups, and each group was subdivided into four replicates (130 birds per replicate). The birds were randomly allocated into a control group fed basal diet (CB); control group fed low-energy diet (CL); and birds fed low-energy diets supplemented with different enzyme formulations. The enzyme formulations used were Xylam 500® (CLX group), Hemicell® (CLH group), Avizyme® (CLA group), and Megazyme® (CLM group,) following the doses recommended by the manufacturers. The growth performance of CLA and CLH group birds was significantly improved when compared with CL. In comparison with CB, Avizyme® significantly (p < 0.001) increased the intestinal PEPT1, GLUT2, ACC, and IL-2 expression; PEPT1 facilitates the absorption of micronutrients. In conclusion, exogenous multienzyme complexes may be included in the low-energy diet to enhance the performance of broiler chickens (Avizyme® ˃ Hemicell® ˃ Megazyme®), and reduce the diet cost by up-regulating the expression of intestinal nutrient transporter genes, and improving the immunity and serum biochemical parameters of broiler chickens.