Supplementation of grape seed extract improves the gastrointestinal development of weaned beef calves

This experiment evaluated the potential benefits of grape seed extract (GSE) supplementation on digestive enzyme activity, gastrointestinal morphology and barrier function of weaned beef calves. A total of 30 Simmental crossbred male calves with similar age (68 ± 6 d) and body weight (83.47 ± 4.59 kg) were randomly assigned to 2 groups: control (CON) (fed basal diet) and GSE (fed basal diet and 4 g/d GSE per animal). The experimental period was 60 d. Compared with CON group, the serum diamine oxidase and lipopolysaccharide concentrations in GSE group were reduced (P < 0.05), while the activity of ruminal cellulase and ileal trypsin and chymotrypsin displayed an opposite pattern (P < 0.05) between the groups. The ruminal papilla height and surface area of GSE group were higher (P < 0.05) than those of CON group. A similar pattern of ileal villus surface area and villus-to-crypt ratio was observed between the groups. Also, GSE supplementation increased (P < 0.05) the secretory immunoglobulin A content in the jejunum and ileum. The rumen, jejunum and ileum of GSE calves displayed lower (P < 0.05) tumor necrosis factor-alpha and higher (P < 0.05) interleukin-10 mRNA expressions. Calves supplemented with GSE increased (P < 0.05) the expressions of occludin and zonula occludens-1 in the rumen and ileum. The findings in this study suggested that GSE improved the gastrointestinal development of weaned beef calves.