EFFECTS OF DIETARY SUPPLEMENTATION OF SYNBIOTICS ON GROWTH, INTESTINAL BARRIER FUNCTION AND CECAL MICROORGANISMS OF CHERRY VALLEY DUCKS

The present study was set out to explore the effects of diets supplemented with synbiotics, as a possible antibiotic substitute, on growth performance, intestinal barrier function and cecal microorganisms of Cherry Valley ducks. Briefly, a total of 540 Cherry Valley ducks (one-day-old) were randomly categorized into 3 groups for 42 days: control group (basal diets free from the antibiotic), antibiotic group (basal diets supplemented with 40 mg/kg bacitracin zinc), and synbiotic group (basal diets supplemented with 1 000 mg/kg synbiotic). Each group consisted of 6 replicates of 30 ducks each. In synbiotic group, average-day-gain (ADG) throughout the trial period (p≤0.05) and average-day-feed-intake (ADFI) during the starter and grower periods (p≤0.05) were increased as compared with the control group. Moreover, dietary synbiotics enhanced ileal villus height to crypt depth (V/C), decreased ileal crypt depth compared with the control group (p≤0.05). In addition, the synbiotics increased numbers of Intraepithelial lymphocytes (IELs) and goblet cells in the small intestine (p≤0.05), and secretory IgA (sIgA) concentration in the duodenum and jejunum (p≤0.05) of 42-day-old ducks as compared with the control group. Furthermore, synbiotics supplementation increased the mRNA expression of jejunal mucosal occluding (OCLN) and the population of Bifidobacterium in cecal chyme (p ≤ 0.05). In conclusion, diets supplemented with synbiotics could improve growth performance and intestinal morphology, enhance intestinal barrier function, and modulate the cecal microorganisms in Cherry Valley ducks.