Effects Of Astragalus Polysaccharides And Vitamin C On Egg Quality And Immune Function Of Laying Hens In High Temperature Environment

In recent years, antibiotic residues in animal foodstuff problem have attracted many attentions. Eggs are rich in protein, has been the important source of protein. But if the antibiotic is added in the laying hens feed, the eggs will also contain antibiotics and the drug resistance will be harmful to human beings. Therefore, it has become a hot topic to study how to use non-antibiotic additive to prevent the disease. The experiment was conducted to investigate the effects of Astragalus Polysaccharides and Vitamin C on egg quality and immune function of laying hens.144,40-week old Hyline Brown hens were randomly allocated into 3 groups (basal diet group, Astragalus Polysaccharides group, Vitamin C group),with 4 replicates of 12 hens in each. After 30 days, choose three hens in each group blooded. The results were as follows:Add APS and VC in diet had no significant effect on the protein height and the HA units, but the HA units had an increasing trend after adding APS (P> 0.05). At the later stage of the experiment, compared with the control group, the yolk color of the vitamin C treatment group increased by 8.6%(P> 0.05),both vitamin C and APS group significantly increased the strength of eggshell (P<0.05).Add APS and Vc in diet had no significant effect on MCH, MCHC, WBC, MCV, HCT, RBC, and HGB, but the RDW-CV significantly decreased.Add APS and Vc in diet had no significant effect on the laying rate, but in Vc group the laying rate increased at the end of experiment but not significant. During the whole period, the ADFI of APS group was lower than that of the other groups (P<0.05). During the first three weeks, the feed/egg ratio was significantly lower, and the difference was not significant compared with the control group in the fourth week.Add APS and Vc in diet had no significant effect on the antibody titer of the avian influenza vaccine, but the antibody titer had an increasing trend after adding APS (P> 0.05).In summary, astragalus polysaccharides and vitamin C can enhance the strength of eggshell, astragalus polysaccharide can reduce the feed intake of laying hens, maintain the laying rate, reduce feed egg ratio, and has adjuvant effect, increase antibody titer. Therefore,supplemented with 0.5 g/kg astragalus polysaccharide have a better effect than 0.2 g/kg vitamin C.