Physiological Stress Responses to Prolonged Exposure to MS-222 and Surgical Implantation in Juvenile Chinook Salmon

AbstractThis study simulated large-scale monitoring program operations to evaluate the responses of age-1 Chinook Salmon Oncorhynchus tshawytscha to tricaine methanesulfonate (MS-222; 80 mg/L) exposure and intracoelomic acoustic microtransmitter implantation. The MS-222 exposure effects and appropriate exposure times for juvenile Chinook Salmon undergoing intracoelomic implantation were determined using blood analytes (Na+, K+, Ca2+), blood pH, plasma cortisol, and survival immediately following anesthetic exposure (3, 6, 9, and 12 min on day 0) and over a recovery period (days 1, 7, and 14). In addition, effects were examined in surgically implanted and nonimplanted fish (but exposed to MS-222 for 3 min) over a 14-d recovery period. Regardless of anesthetic exposure time, there were no mortalities during exposure on day 0 or over the recovery period. On day 0, MS-222 exposure treatments of 9 and 12 min resulted in significantly higher Na+ and Ca2+ and lower K+, indicating a reduced ability to maintain os...