Oral and injectable applications of erythromycin in salmonid fish culture

Erythromycin is a macrolide antibiotic effective against Renibacterium salmoninarum, causative agent of bacterial kidney disease in salmonids. Although erythromycin is used on an experimental basis in private and conservation hatcheries, the drug is not registered with the US Food and Drug Administration for use in fish culture. Residues of erythromycin are retained in the tissues of juvenile and adult salmon for some time following administration of oral or injectable forms of the drug, a characteristic that may be important in the drug's efficacy against the slow growing R. salmoninarum pathogen. Before erythromycin can be registered, additional information must be collected about efficacy, toxicity, and environmental consequences of administration.