Abstract
Gut health is important for digestion and absorption of nutrient for animals. The purpose of this study was to investigate the therapeutic effect of enzymes and probiotics alone or in combination on the gut health of broilers fed with newly harvested corn diets. A total of 624 Arbor Acres Plus male broiler chickens were randomly divided into 8 treatment groups (PC: normal corn diet, NC: newly harvested corn diet, DE: NC + glucoamylase, PT: NC + protease, XL: NC + xylanase, BCC: NC + Pediococcus acidilactici BCC-1, DE + PT: NC + glucoamylase + protease, XL+BCC: NC + xylanase + Pediococcus acidilactici BCC-1). Each group was divided into 6 replicates, with 13 birds each. On d 21, intestinal morphological, intestinal tight junction and aquaporins gene expression, cecal short-chain fatty acid concentrations, and microflora were measured. Compared with the newly harvested corn diets (NC), supplemental glucoamylase (DE) significantly increased the relative abundance of Lachnospiraceae (P < 0.05) and decreased the relative abundance of Moraxellaceae (P < 0.05). Supplemental protease (PT) significantly increased the relative abundance of Barnesiella (P < 0.05), but the relative abundance of Campylobacter decreased by 44.4%. Supplemental xylanase (XL) significantly increased the jejunal mRNA expressions of MUC2, Claudin-1, and Occludin (P < 0.01), as well as the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). Supplemental DE combined with PT increased the ileal mRNA expressions of aquaporins (AQP) 2, AQP5, and AQP7 (P < 0.01). Supplemental BCC significantly increased the jejunal villus height and crypt depth (P < 0.01), the jejunal mRNA expressions of MUC2, Claudin-1 and Occludin (P < 0.01), and the relative abundance of Bacteroides (P < 0.05). Supplemental xylanase in combination with BCC significantly increased jejunal villus height and crypt depth (P < 0.01), the ileal mRNA expressions of AQP2, AQP5 and AQP7 (P < 0.01), and the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). This suggests that inclusions of supplemental protease (12,000 U/kg), glucoamylase (60,000 U/kg), or Pediococcus acidilactici BCC-1 (10(9) cfu/kg) individually or in combination with xylanase (4,800 U/kg) in the newly harvested corn diets can alleviate diarrhea in broilers, and be beneficial for the gut health.