Development of Multivalent Inactivated Vaccine of Avian Escherichia Coli with Compound Adjuvant

Multivalent inactivated vaccine of avian escherichia coli with compound adjuvant is developed by use of the advantageous pathogenic E coli bacterial fragments which were collected in Shanxi Province as antigen material,and complex composition immune adjuvant of mineral oil and astragalus polysaccharide.By the immune effect tests,immunologic defend time tests and vaccine keep time tests,the resulted is listed as following:7 days after immunization,the bird can produce a strong immune capability to E coli,while the conventional vaccine(the control group Ⅱ)required 14 days.About 6 weeks after the vaccine inoculation,the O78 serum antibody titers could achieved 1∶32(maximum 1∶53)and preserved more than 6 weeks,while the maximum value of the conventional vaccine was 1∶18.The immune protection period of vaccine kept more than 5 months(which of common vaccine was 4 months).When the vaccine is stored in 4～8 ℃,the period of validity was no less than 14 months.The results of laboratory and regional tests showed that the vaccine produced antibodies circulating in early time,with the virtue of security and high rate of immune protection.