Abstract The effects of two stunning methods (carbon monoxide asphyxia, CO, and electroshock, E) on blood plasma parameters, rigor index, fillet pH and shape changes, ATP breakdown and Adenylate Energy Charge (AEC) in muscle immediately post mortem were investigated in rainbow trout (Oncorhynchus mykiss) kept in tanks containing water set at 8 °C or 12 °C. Both the methods here adopted induced a stress-response which, however, was not able to affect the rigor mortis development and fillet pH. The fillets from the E group showed the strongest length contraction and width increase at 48 h post mortem. The CO stunning method exhibited the highest levels of both ATP and AEC in the muscle immediately after death, equal to 2.28 µmol/g and 0.83, respectively, while 1.12 µmol/g and 0.64 values were found in the E group. In addition, we found that the water temperature might interact with the stunning method and minimise the stress response. In the present trial, the most suitable use of the CO stunning method would be coupled with 12 °C of rearing water temperature to better preserve ATP and AEC in muscles. Highlights CO stunning preserves ATP and AEC in trout muscle better than electrical stunning Water temperature might interact with the stunning and minimise the stress response CO stunning is suggested to be coupled with 12 °C of water temperature Electricity should be avoided at 8 °C of water temperature

中文翻译：

---

击晕方法对在两种不同温度下养殖的虹鳟鱼（Oncorhynchus mykiss）的前期严酷变化的影响

摘要 研究了两种击晕方法（一氧化碳窒息，CO 和电击，E）对死后肌肉中血浆参数、严密指数、鱼片 pH 值和形状变化、ATP 分解和腺苷酸能量电荷 (AEC) 的影响。虹鳟鱼 (Oncorhynchus mykiss) 保存在水温为 8 °C 或 12 °C 的水箱中。这里采用的两种方法都会引起应激反应，但不能影响尸体僵硬的发育和鱼片的 pH 值。E 组的鱼片在死后 48 小时显示出最强的长度收缩和宽度增加。CO 击晕方法在死后立即显示肌肉中最高水平的 ATP 和 AEC，分别等于 2.28 µmol/g 和 0.83，而在 E 组中发现的值为 1.12 µmol/g 和 0.64。此外，我们发现水温可能会与击晕方法相互作用并最大限度地减少应激反应。在目前的试验中，最合适的 CO 击晕方法是与 12 °C 的饲养水温相结合，以更好地保存肌肉中的 ATP 和 AEC。亮点 CO 击晕比电击晕更能保护鳟鱼肌肉中的 ATP 和 AEC 水温可能与击晕相互作用并最大限度地减少应激反应 CO 击晕建议与 12 °C 的水温相结合 8 °C 的水温应避免电击温度