Risk factors associated with clinical Bacterial Kidney Disease (BKD) in marine farmed Atlantic salmon (Salmo salar L.) in New Brunswick, Canada

In a retrospective study of a large number of Atlantic Canadian salmon aquaculture sites between 2006 and 2012, more than half experienced cases of Bacterial Kidney Disease (BKD) (Boerlage et al., in press). Salmon infections with Renibacterium salmoninarum can be subclinical or clinical. In the latter case there are increased levels of mortality and/or clinical signs (Murray et al., 2011). Transmission of BKD can occur vertically (Evelyn et al., 1984; Lee and Evelyn, 1989) and horizontally (Balfry et al., 1996; Evenden et al., 1993). Little analytical research has been done to establish risk factors for mortality attributed to BKD in marine salmon aquaculture. Objective was to identify production and environmental factors associated with infection transmission leading to clinical BKD at marine sites in eastern Canada.