DEVELOPMENT OF ANTIBODIES IN MICE, RABBITS AND PIGS AFTER ADMINISTRATION OF AN INACTIVATED OIL VACCINE CONTAINING ROTAVIRUS AND ESCHERICHIA-COLI STRAINS WITH FIMBRIAL ANTIGENS K88, K99 AND 987P

In trials with mice, rabbits and weanling piglets, four experimental charges of a combined inactivated oil vaccine against diarrhoeas in mammals were tested: the vaccine was to be implanted to sows and it contained porcine rotavirus (PRV); two charges also contained bovine rotavirus and bacterins of enterotoxicogenic strains of E. coli with protective antigens K88, K99 and 987P. At low starting antibody titres the twofold i. m. implantation of 0.2 ml vaccine stimulated in mice the production of antibodies to reach the average titre value of 1:128 against PRV and of 1:256 against BRV; in rabbits the twofold i. m. implantation of 2 ml vaccine stimulated the antibody development to reach the average titres of 1:508 or 1:500, and in weanlings after the twofold i. m. implantation of the vaccine the titres were 1:1028 or 1:469; in mice agglutination antibodies to antigen K88 had the average value of 1:68, to antigen K99 the value of 1:44 and to antigen 987P the value of 1:8192; in rabbits the respective titres were 1:285, 1:136 and 1:6006 and in pigs 1:570, 1:631 and 1:8192. The antibodies to antigen 987P persisted at the same level in pigs for six months. Even though there was a gradual decrease in the antibodies to antigens K88 and K99, at that time the values were 9.8 times, or 15.2 times higher than the starting values, and only the antibodies to PRV dropped to the pre-vaccination level. Repeated administration of vaccine to pigs after six months from revaccination induced, with the exception of antigen 987P, an increase in antibodies in a fortnight to reach such titres that were recorded after revaccination.