Submitted to: American Fisheries Society Book Series
Publication Type: Book / Chapter
Publication Acceptance Date: June 21, 2012
Publication Date: N/A
Yersinia ruckeri, the causative agent of Enteric Redmouth Disease (ERM), is a disease of salmonid fish species that is endemic in areas of the world where salmonids are intensively cultured. The disease causes a chronic to acute hemorrhagic septicemia which can lead to high rates of mortality particularly to farmed rainbow trout. ERM in rainbow trout has been successfully controlled by immersion vaccination for years but recent losses in vaccinated fish have occurred and have been associated with new strains of the pathogen thought to be resistant to vaccination. This book chapter describes the disease caused by Y. ruckeri including information on its geographical range, host species, epizootiology, clinical signs and methods for its diagnosis. The emergence and spread of vaccine resistant forms of Y. ruckeri poses a threat to salmonid culture and thus monitoring of these strains has become increasingly important.