Application And Generalization Newcaste Disease Vaccine Immunity Enhancement Effect Of Astragalus Polysaccharide To Chicken

The Astragalus Polysaccharide(APS)is one of main active constituents of Chinese herbal Astragal that functions in the promoting antibody formation,and the inducibility of interferon produces,improving immune response.APS had been mainly applied to injection purpose,and gotten short time for immunity.However,non-typical Newcastle Disease(ND)occurred unceasingly in recent years,which had been still not to be able to be controlled although using the vaccine many times.Therefore it is necessary to develop new type APS to be used to enhance the chicken immunity,and the vaccine immunity effect,to effectively control this disease.APS extracted from Chinese herbal Astragalus with the aqueous extract,CaO aqueous extract and Na₂CO₃ aqueous extract respectively were computed the receiving rate and cost,and determined the APS content with the phenol-sulfuric acid method.The results indicated that the APS extraction rate and the content of CaO aqueous extract were remarkable higher than the aqueous extract and Na₂CO₃ aqueous extract(p＜0.01).The cost of CaO aqueous extract was remarkable lower than the aqueous extract(p＜0.01)and Na₂CO₃ aqueous extract(p＜0.05).The diagnosis chicken immunity function change Monitor method-hem agglutination inhibition test,thymus dependent lymphocyte erythrocyte rosettes assay and the acida-naphthy acetate esterase determination experiment were established through the broiler ND immunizing experiment.While respectively immune broiler and young layer which were aged 7 days with NDâ…£vaccine,oil-emulsion vaccine,â…¡vaccine andâ… vaccine(at the age of 30 days),the coordinate use different dosage APS solution to drink water,with the oil-emulsion vaccine,mix or the distinction hypodermic injection,as a diluent to dilute NDâ…¡vaccine,then to drop eyes and nose,with NDâ… vaccine mix or the respectively intramuscular injection,through determining and comparing immune function changes on 10,20 and 30 days after immunity,it was discovered that increase 20mg/only APS was the best dosage,It indicated that enhanced function effect obviously to different type vaccine immunity of chicken ND,and made the antibodies level higher.Different forms of prepared APS with only 20mg per chicken for drinking, hypodermic injection,and intranmseular injection,drop eyes and nose as chicken were injectedâ…£vaccine of chicken ND at 7 days.The results showed that the immune body level of test groups were higher than the control groups after using different forms of APS on 10,20 and 30 days,but the test groups were not responded remarkably.The experiment showed that the APS was beneficial to drink with water,avoid catching stress,save the manpower,so was the best form.Acute and chronic toxicity tests also indicated that APS was safe to chicken,there were no any toxic and side effect.The potency test showed that APS might enhance thymus dependent lymphocyte E-rosette formation rate and bursa dependent lymphocyte formation rate.It indicated that APS might enhance cell immunity function and humeral immunity function of chickens.The field test and regional test through 27000 chicken and young layers indicated that chickens were well immune with ND vaccine around 3 days at the age of 7 days,meantime with drinking 2%APS solution might strengthen organism immunity function,reduced the incidence and death rate.It had remarkable economic efficiency.