Effect of extracts from bursa of fabricius on mouse immunity

In experiment,several immunal parameters including organ indexes,number of WBC,quantity of lymphocytes,number of ANAE + lymphocytes,histological change of spleen,PRV antibody level,challenge results of mice inoculated with different doses of BF′s extracts and PRV inactive vaccine were measured to indicate effects of BF′s extracts on mice immunity.In conclusion,moderate dosage (0 25 mg per mice)of BF′s extracts can promote the humoral and cell immunity in the mice and muscle injection is better way than oral inoculation way.Nevertheless,high dosage of BF′s extracts(1 mg per mice)positively affect humoral immunity,but negatively affect cell immunity.These effects are related to dosages,inoculative routes and time.