Abstract
The effects of immersion administration of levamisole on the activation of nonspecific defense mechanisms were examined in carp Cyprinus carpio. Survival rates after a challenge with Aeromonas hydrophila were enhanced by immersion in levamisole (10μg/ml, 25°C, 24h). The effectiveness appeared 1 day after administration and lasted for at least 2 weeks. Chemotactic ability, phagocytic activity and production of active oxygen (chemiluminescence) in head kidney phagocytes were activated by immersion.
This phagocyte activation might give levamisole-administered carp enhanced protection against an A. hydrophila challenge, at the beginning of the infection.
