Vaccines for duck cholera and duck plaque. II. Relationship of agglutinating antibody titer and protective produced by duck cholera vaccines
1985
Areerat Pongsopida | Santi Thoongsuwan | Vimolmas Lipipan (Chulalongkorn Univ., Bangkok (Thailand))
Whole cell and cell components of Pasteurella multocida serotype 8 : A were tested against duck cholera. Three immunizing agents were prepared from whole cell (agar), capsule and protoplast. The whole cell (broth) was obtained from Department of Livestock. The immunity response was evaluated by both agglutination test using autoclaved culture as antigen and the in vivo protection test to determine the relationships of serum antibody and the protective immunity. All vaccines stimulated the highest immunity at one week after first vaccination but provided lower immune response when the booster dose was administered. Whole cell (broth) vaccine induced higher antibody titer than whole cell (agar) vaccine. The active protection of the whole cell (agar) vaccine and whole cell (broth) vaccine against P. multocida were 100 % while the protoplast and capular vaccines provided only 80 % and 50 % protection. All control ducks died within 24 hrs after challenge. The serum antibody titer of every dead duck before challenge was 20 and so did some survival ducks. The results were not sufficient to explain the correlation between the serum antibody and the resistance of ducks against P. multocida.
显示更多 [+] 显示较少 [-]