Risk factors for abdominal adhesions in Atlantic salmon, Salmo salar L.

• Published in: Journal of Fish Diseases
• Main Authors: Vågsholm, I., Djupvik, H. O.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1999
• Subjects: Norway; Slaughter; Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1046/j.1365-2761.1999.00137.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1046%2Fj.1365-2761.1999.00137.x; https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1365-2761.1999.00137.x

The risk factors for abdominal lesions at slaughter in Atlantic salmon, Salmo salar L., were examined in a cohort study in Hordaland County, Norway, in which 187 slaughter‐groups consisting of 5000 salmon were followed from seawater introduction in April 1994 until slaughter in February 1996. There were major differences in the risk of abdominal lesions between egg suppliers. Salmon vaccinated with a vaccine using plant oil adjuvants appeared to be at lower risk (relative risk, RR = 0.5) of abdominal lesions. The occurrence of epitheliocystis on the smolt farm was associated with an increase in the risk of abdominal lesions (RR = 3.0). An increase in smolt weight from 0.047 to 0.107 kg increased the risk of abdominal lesions and spinal deformities (RR = 1.5). If salmon were raised in a fjordic instead of an oceanic site, the risk of abdominal lesions increased (RR = 3.6). An increase in the number of days at sea decreased the risk of lesions (RR = 0.6). Hence, it appears that the observed frequency of abdominal lesions might have more determinants than the type of vaccine and vaccination procedure.