Effects of encapsulated cinnamaldehyde on villus height (A), crypt depth (B) and ratio of villus height and crypt depth (C) on duodenum, ileum, and jejunum in broilers. NC, negative control, birds fed with basal diet; PC, positive control, birds fed with 30 mg/kg avilamycin premix; EOL, birds fed 50 mg/kg encapsulated cinnamaldehyde; EOH, birds fed 100 mg/kg encapsulated cinnamaldehyde. Significant differences are indicated by letters (a, b).