Comparative Study Of The Effects Of Eucommia Leaves And Probiotics On Immune Function Of Laying Hens

〔Objective〕Livestock immune suppression and product residue problem which caused by the abuse of antibiotics aroused wide concern in the industry. Improving the animal immunity by using the nutrition way is an important measure for the sustainable development of animal husbandry in China. This experiment explored effect comparison of probiotics and eucommia leaves on the immune function of laying hens.〔Method〕Five hundred and forty Hy-Line brown laying hens aged 23 weeks were selected and randomly allocated into 3 treatments with 6 replicates of 30 birds. The dietary treatments included the control group, fed the basal diet,whlie the experimental group that were fed with probiotics of 0.5% and eucommia leaves of 0.5% diets. Newcastle disease vaccine was injected at the beginning of the prefeeding period,while avian influenza vaccine was injected at the beginning of the formal testing period. The experiment lasted for 9 weeks, which included the prefeeding period of 1 weeks and the formal experimental period of 8 weeks. The test index for different experimental group were laying hens’ production performance,egg quality and immune indexes(IgA,IgG,IgM,avian influenza antibody titer, newcastle disease antibody titer, immune organ index and related gene expression).〔Result〕1.Production performance:Addition of probiotics and eucommia leaves in diet significantly increased the laying rate of laying hens(P<0.05), significantly reduced the average daily feed intake(P<0.05) and significantly reduced the feed egg ratio(P<0.05),while the difference between eucommia leaves and probiotics group was not significant(P>0.05).The average egg weight was not significantly different(P>0.05). The characteristic is to extend the trial period, the effect is more obvious.2.Egg quality:The difference of egg quality(eggshell strength, eggshell thickness, egg shape index, high protein, ha’s unit and egg yolk color) was not significant(P>0.05).3.Immunoglobulin:Addition of probiotics and eucommia leaves in diet significantly increased the Serum IgA,Ig G,IgM levels of laying hens(P<0.05). In the trial period 4W, IgA that diets added eucommia leaves group was significantly higher than that of probiotics group,whlie IgG that diets added probiotics group was significantly higher than that of eucommia leaves group(P<0.05). In the trial period 8W, IgM that diets added eucommia leaves group was significantly higher than that of probiotics group(P<0.05).4.AI and ND antibody titer: Diets adding of eucommia leaves and probiotics could slow the rate of decline of AI antibody titer ND antibody titer. Eucommia leaves group’s peak higher and faster than probiotics group, and could slow the rate of decline, while the effect of eucommia leaves was better than probiotics. In the trial period the 1W,2W, AI and ND antibody titers that added probiotics group, eucommia leaves group and control group were not significant(P>0.05). In the trial period the 4W, AI antibody titers those diets added probiotics and eucommia leaves were significantly higher than those of the control group(P<0.05), while ND antibody titers those diets added eucommia leaves were significantly higher than diets added probiotics and the control group(P<0.05). In the trial period the 8W, AI and ND antibody titers that diets added eucommia leaves group and probiotics group were significantly higher than that of control group(P<0.05) and eucommia leaves group was significantly higher than probiotics group(P<0.05).5.Immune organ index:Adding eucommia leaves and probiotics, test final laying chicken liver index and spleen index were increased, but the difference was not significant(P>0.05).6.Related gene expression:Expression of IFN-γgene in chicken spleen that adding eucommia leaves group and probiotics group were significantly higher than the control group(P<0.05), and eucommia leaves group gene expression was significantly higher than probiotics group(P<0.05).〔Conclusion〕1.Eucommia leaves and probiotics in the diet had obvious effects on the production performance of laying hens,while no significant effect on egg quality.2.Eucommia leaves and probiotics could significantly improve the immune function of laying hens and eucommia leaves were better than probiotics. This effect may be related to the increase of serum immunoglobulin levels and the regulationthe of IFN-γgene expression.