PROTECTION OF VACCINATED PIGS AGAINST HOMOLOGOUS AND HETEROLOGOUS EXPERIMENTAL HAEMOPH1LUS PARASUIS INFECTIONS

摘要

Fifteen serotypes of Haemophilus parauis (Hps) have been described (1). Protection by vaccination against polyserositis caused by Hps has been described (2, 3). Polyserositis caused by Hps (Glasser's disease) is of increasing importance. Due to the very inconsistent occurrence of outbreaks in the herds it is very difficult to find suitable hosts for field experiments. By challenge experiments using pigs without antibodies to Hps. the clinical and pathological picture is very similar to acute or peracute spontaneous cases. The serological status can be measured by ELISA using an Hps type 5 cell extract as antigen. This paper describes a series of experimental infections of seronegative pigs with Hps of serotypes 1, 5, 12, 13, and 14, respectively. In our hands these serotypes have been among the most pathogenic and are among the most frequently isolated types. Simultaneously we describe the efficacy of a new vaccine containing Hps serotype 5 antigen and Diluvac Forte as adjuvant.