Effects of chicory polysaccharides on the production performance, immunity and intestinal health of laying hens in the late phase of the laying cycle

Chicory polysaccharide (CP) is one of the important functional active substances in chicory. This experiment was aimed to investigate chicory polysaccharide on production performance, immunity and intestinal health of laying hens in late laying period. The 540-day-old Dawu Golden Phoenix were divided into two groups randomly, including control group and chicory polysaccharide group (1.5%), the test period was 30 days. The Results were as following : Adding Chicory polysaccharides increased laying rate (P<0.05) and reduce average egg weight (P<0.05), but had no impact on feed-to-egg ratio(P>0.05). The blood sugar content in the serum biochemical index was higher in the chicory polysaccharide group than in the control group, and the antioxidant index was also generally improved. Besides, spleen immune factors () were significantly increased (P<0.05), the CD4+/CD8+ ratio was elevated. Moreover intestinal tight junction proteins Occludin, ZO-1 and ZO-2 were significantly increased in the chicory polysaccharide group. Despite the species diversity of intesinal flora had no difference between the two groups, the relative abundance of microorganism at phylum level and genus level were both changed. At the phylum level, the relative abundance of Firmicutes in the chicory polysaccharide group increased(78.53%-88.30%), and the relative abundance of Actinobacteria decreased (12.85%~.06%). At the genus level, the relative abundance of Lactobacillus was imporved (18.23%~57.74%). This indicated that chicory polysaccharide enhanced the intestinal barrier function and improved the diversity of intestinal flora. In conclusion, chicory polysaccharidecould improve laying rate, splenic immune function, intestinal barrier function and diversity of intestinal flora of laying hens in the late laying period.