IMMUNOLOGICAL REACTIONS OF YOUNG HAFLINGE R HORSES DUE TO CONTROLLED ORAL AND INHALATIVE CHALLENGE WITH FUNGI AND MITES

Six Haflinger horses (age ranged between 11 and 16 months) were repeat edly exposed to a mixture of moulds and forage mites (Aspergillus flav us, Penicillium viridicatum and Acarus siro) first by ingestion, follo wed by inhalation and finally subcutaneous injection. Before, during a nd after these challenge periods serum samples were harvested in defin ed intervals and analyzed for antigen-specific antibodies in an ELISA- system especially developed for this study. None of the animals develo ped clinical signs of allergy. While the sera taken after subcutaneous injection gave strong positive reactions in the ELISA, none of the ho rses showed an increase in antibody-concentration after the oral chall enge. Only one of the six horses indicated a slight increase in mite-s pecific-antibody-titer upon inhalation challenge.