血清2型鸭疫里默氏杆菌制苗用菌株的筛选及灭活油乳剂疫苗的研制

SCREENING OF SEROTYPE 2 RIEMERELLA ANATIPESTIFER CANDIDATE STRAINS FOR THE DEVELOPMENT OF AN INACTIVATED OIL-EMULSION VACCINE

血清2型鸭疫里默氏杆菌(Riemerella anatipestifer,RA)分离株经雏鸭体内复壮、回收、鉴定后,选取其中2株细菌NJ3和Yb2进行毒力测定,结果表明其半数致死量分别为5.62×107CFU和1.07×105CFU。选取5株细菌制备灭活油乳剂疫苗后免疫鸭,并进行攻毒保护试验。结果表明不同菌株制备的疫苗均可使免疫鸭产生高水平的RA特异性ELISA抗体和攻毒保护力,但是攻毒保护性差异较大,NJ3免疫后的攻毒保护性最好。抗体检测及攻毒保护实验表明NJ-3是较理想的制苗用菌株。

Serotype 2 Riemerella anatipestffer strains were reisolated and characterized after inoculated into ducklings. Among obtained isolates, strains NJ3 and Yb2 were titrated in ducklings. The median lethal doses （LDs0） were 5.62-107CFU for strain NJ3 and 1.07x 10^5CFU for Yb2. Five reisolated strains （SC-2, Yb2, Th4, JY-1 and NJ-3） were selected to prepare inactivated oil-emulsion vaccines that were administered into Cherry Valley ducklings. All ducklings immunized with the above vaccines generated high ELISA titers. However, protection against challenge with either N J3 or Yb2 showed significant difference among 5 candidate strains. The best protection in ducklings was obtained when N J3 strain vaccine was used, indicating NJ-3 strain was an ideal candidate for the development of inactivated oil-emulsion vaccine.