Swim bladder stress syndrome in arctic charr (salvelinus alpinus)

• Main Author: Ricks, William Remmert
• Format: Thesis
• Language: English
• Published: University of British Columbia 1991
• Subjects: Arctic; Northwest Territories; Arctic charr; Salvelinus alpinus
• Online Access: http://hdl.handle.net/2429/30279

I investigated the condition known as Swim Bladder Stress Syndrome (SBSS) in a Nauyuk Lake, Northwest Territories strain of Arctic charr (Salvelinus alpinus). Induction of the condition was attempted through an extended period of acute sessions of applied handling stress. Water quality was controlled throughout the entire 5 month project. Blood analyses were performed (packed cell volume, plasma Cortisol and glucose) to confirm that the fish had been physiologically stressed. In addition, bacteriology, virology, histopathology and a tissue homogenate injection trial were performed in an attempt to ascertain the exact etiology of this condition. The charr were subjected to two stress treatments (stressed and non-stressed), both treatments occurring at each of two density levels (75 kg/m³ and 150 kg/m³). The incidence of SBSS in the treatment groups was not statistically significant (Log-likelihood ratio; P > 0.05), although seven out of a total of eight (87.5%) cases were fish from high density groups. Cortisol levels were higher in the low density groups as opposed to the high density groups for all three samplings, significantly so at the third sampling. Bacteriology, virology, histopathology and the tissue homogenate injection trial all failed to demonstrate any source of the condition. It is questionable whether Swim Bladder Stress Syndrome in Arctic charr is in fact due to stress as previously indicated in the scientific literature. Land and Food Systems, Faculty of Graduate