Effects of dietary xylooligosaccharides supplementation on the intestinal morphology, nitrogen metabolism, faecal ammonia release, antioxidant capacity, and immune organ indices of broilers

Abstract

This aim of the present study was to evaluate the effects of dietary xylooligosaccharides (XOS) on the intestinal morphology, nitrogen metabolism, faecal ammonia release, antioxidant capacity, and immune organ indices of broilers fed corn-soybean meal diet. A total of 240 healthy 1-day-old Arbour Acres (AA) broilers were randomly divided into four treatment groups receiving XOS supplementation of 0 (Control), 150, 300, and 450 mg/kg to basal diet for 6 weeks. Six replicates with 10 birds each were prepared for each treatment. Results showed that the villus height of duodenum, jejunum, and ileum and the villus height to crypt depth ratio of jejunum were increased significantly in the broilers receiving 150 mg/kg XOS compared with those in the Control (p < 0.05). Nitrogen utilisation from day 19 to 21 was higher in the 150 mg/kg XOS group than in the Control (p < 0.05). Moreover, the addition of 150 mg/kg XOS reduced the nitrogen excretion from day 40 to 42 (p < 0.05), and all XOS treatments increased the nitrogen utilisation from day 40 to 42 (p < 0.05). All dietary XOS supplementations decreased the faecal ammonia concentration on day 21 (p < 0.05), and the addition of 150 and 450 mg/kg XOS induced a lower faecal ammonia concentration compared with that of the Control on day 42 (p < 0.05). Dietary supplementation of 300 and 450 mg/kg XOS enhanced the activity of serum total antioxidant capacity compared with that in the Control and 150 mg/kg XOS groups at the age of 42 days (p < 0.05). Supplementation with 450 mg/kg XOS significantly increased the index of thymus (p < 0.05) and the content of total protein compared with those of the Control at the age of 21 days (p < 0.05). Therefore, dietary supplementation with 150 mg/kg XOS have a beneficial effect on broilers. Highlights Dietary supplementation with XOS increased the villus height of duodenum, jejunum and ileum, and the VH/CD ratio of jejunum. Dietary supplementation with XOS enhanced nitrogen metabolism and reduced faecal ammonia release.