Domestication compromises athleticism and respiratory plasticity in response to aerobic exercise training in Atlantic salmon (Salmo salar)

• Published in: Aquaculture
• Main Authors: Zhang, Yangfan, Timmerhaus, Gerrit, Anttila, Katja, Mauduit, Florian, Jorgensen, Sven Martin, Kristensen, Torstein, Claireaux, Guy, Takle, Harald, Farrell, Anthony P.
• Format: Text
• Language: English
• Published: Elsevier Science Bv
• Subjects: socio; envir; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.1016/j.aquaculture.2016.05.015; https://archimer.ifremer.fr/doc/00334/44518/44214.pdf; https://archimer.ifremer.fr/doc/00334/44518/

Commercially selective breeding of Atlantic salmon (Salmo salar) primarily for rapid growth may compromise cardiorespiratory robustness and its related phenotypes. Therefore, a suite of respiratory indices was used to evaluate aerobic capacity and hypoxia tolerance to test the hypothesis that exercise training can improve the athletic robustness in both domesticated and wild strains of Atlantic salmon, but with the domesticated strain having a less cardiorespiratory plasticity and a lower athletic robustness than the wild strain. We also tested a second hypothesis that a constant acceleration screening protocol should segregate fish according to athletic robustness based on their swimming ability. These hypotheses were tested with parr from Bolaks (domesticated) and Lærdal (wild) strains of Atlantic salmon that were reared under identical hatchery conditions. After screening into either inferior (bottom 20%) or superior (top 20%) swimmers, the four groups of fish (two strains and two swimming performance levels) either were given an 18-day exercise-training regime (an incremental water current of 2.0–2.8 fork lengths s− 1), or were maintained at the control water current (0.5 fork lengths s− 1) for 18 days. Subsequently, fish were sampled for metabolic enzyme analysis in red and white swimming muscles (citrate synthase, CS, and lactate dehydrogenase, LDH; n = 15 from each group) and their individual respiratory capacities were comprehensively assessed by measuring the standard metabolic rate (SMR), maximum rate of oxygen uptake (ṀO2max), absolute aerobic scope (AAS), factorial aerobic scope (FAS), excess post-exercise oxygen consumption (EPOC), critical oxygen level (O2crit) and incipient lethal oxygen saturation (ILOS). Contrary to our expectations, the inferior and superior swimmers were indistinguishable in either strain and these data were pooled. While exercise training produced several tangible benefits for the wild fish, it produced very few for the domesticated fish. For example, the wild strain, but not ...