FOOT-AND-MOUTH-DISEASE VACCINE FOR SWINE

  • 1 January 1976
    • journal article
    • research article
    • Vol. 40  (1) , 67-74
Abstract
An inactivated vaccine containing purified foot and mouth disease virus type O1, strain Brugge, emulsified with incomplete Freund''s adjuvant was studied in swine. The antigen mass ranged from 0.02-416 .mu.g in 0.25 ml of vaccine. At 90 days postinoculation (DPI) 33-100% of the swine which had been inoculated with .gtoreq. 0.72 .mu.g of antigen were protected against challenge. There was little protection at 182 DPI although the neutralizing titers obtained with 2.9, 34.6 and 416 .mu.g doses of antigen were similar to those observed at 90 DPI. The 50% protective dose for swine was .apprx. 2.3 .mu.g of antigen, whether used in a freshly prepared state or after storage at 4.degree. C for 105 or 259 days. Significant protection was afforded when small volumes (0.1 and 0.5 ml) of vaccine were applied with a jet injector gun to the ear or neck of swine. Initial tissue reactions at the site of inoculation were minimal with these small doses of vaccine and generally disappeared by 90 DPI.