Use of Corn Silk Meal in Broiler Diet: Effect on Growth Performance, Blood Biochemistry, Immunological Responses, and Growth-Related Gene Expression

SIMPLE SUMMARY: Corn silk meal (CSM), the outer thread-like material found under corn husks, is a by-product of corn cultivation, which has been documented as a traditional medicine with multiple benefits for human health. Broilers cannot produce the enzymes needed to hydrolyze non-starch polysaccharide (NSP), which has been found to increase gut viscosity, and reduce the digestion and utilization of nutrients, thereby resulting in poor animal performance. The objective of this study was to examine the effects of diets supplemented with CSM and NSP on growth performance, blood biochemistry, immunological and growth-related gene expression in broiler chickens. A total of 270 broiler chickens were divided into six experimental groups: (1) basal diets (BD) as control; (2) BD supplemented with 0.5 g/kg feed NSP enzyme; (3) and (4) fed a diet containing 40 and 80 kg/ton of CSM; (5) and (6) fed a diet containing 40 and 80 kg/ton CSM and supplemented with 0.5 g/kg NSP enzyme. The results showed that the dietary inclusion of CSM with the NSP enzyme can improve growth performance, intestinal histopathology parameters, modify plasma lipids, and enhance immune response in broilers. ABSTRACT: The objective of this study was to examine the effects of diets supplemented with corn silk meal (CSM) and non-starch polysaccharide (NSP) enzyme on growth performance, blood biochemistry, immunological response, and growth-related gene expression in broiler chickens. A total of 270 broiler chickens were divided into six experimental groups: (1) basal diets (BD) as control; (2) BD supplemented with 0.5 g/kg feed NSP enzyme; the other four groups are CSM diets as following; (3) and (4) fed diet contain 40 and 80 kg/ton of CSM; (5) and (6) fed diet contain 40 and 80 kg/ton CSM and supplemented with 0.5 g/kg NSP enzyme. Body weight gain (BWG), feed conversion ratio (FCR), protein retention and fiber digestibility were synergistically improved (p < 0.05) when fed CSM supplemented with NSP enzyme. Moreover, a synergistic decrease (p < 0.05) in the serum glucose and total cholesterol were found. Immune organ weights and Newcastle disease virus titers were increased with CSM diets. Interestingly, the relative mRNAs of the growth hormone receptor (GHR) and insulin growth factor (IGF) were increased (p < 0.05) with the CSM and NSP enzyme: the relative mRNA expressions of cholecystokinin (CCK) and leptin were decreased by feeding CSM diets with the NSP enzyme. It could be concluded that the dietary inclusion of CSM with the NSP enzyme might improve growth performance, modify plasma lipids, and enhance immune response in broilers.