THE USE OF BAYPAMUN N IN CROWDING ASSOCIATED INFECTIOUS RESPIRATORY-DISEASE - EFFICACY OF BAYPAMUN N (FREEZE-DRIED PRODUCT) IN 4-10 MONTH OLD HORSES

The efficacy of an immunomodulator, Baypamun N, was tested in 4-10-mon th-old horses which were exposed to stress by weaning, transport and c ommingling with yearlings from different breeders (crowding). Verum (n = 26) and placebo animals (n = 27) received three intramuscular injec tions of the investigational preparations (days 0, 2, 9) starting at t he day of commingling in one stable. The incidence of acute respirator y disease was high during the first 4 weeks after commingling. Approxi mately 50% of ail horses showed seroconversion due to field infection by EHV1 and EHV4 during the observation period. The clinical scores in the Baypamun N group were significantly reduced by 40.3% (P < 0.05) c ompared to the placebo group. The proportion of horses with purulent n asal discharge during the observation period (4 weeks) was also signif icantly reduced by 58.7% (P < 0.01) in the Baypamun N group. Fifty per cent of the horses injected with Baypamun N showed no purulent nasal discharge and therefore no signs of complicated disease of the upper r espiratory airways in contrast to only 14.8% in the non-protected plac ebo group. The challenge conditions studied in this investigation were rather severe because of the permanent exposure of Baypamun N treated individuals to the non-separated and untreated horses (n = 51). This indicates that treatment with Baypamun N is a successful tool to avoid severe clinical consequences of stress in young horses.