Stunning and slaughter methods in gilthead seabream: Animal welfare and muscle quality
海鯛的致昏和屠宰方法：動物福利和肌肉質量
Abstract
European Union directives and international guidelines emphasise the need for humane slaughter practices, with particular attention to the proper stunning of fish prior to slaughter. This study investigates the impact of various combinations of stunning and slaughter methods on the welfare of gilthead seabream (Sparus aurata), a widely farmed species in the Mediterranean and Black Sea regions. Specifically, the study explores electrical stunning, anaesthesia, and no stunning, followed by slaughter using either ice-slurry or the ikejime (hand-held spike tool) technique. Fish were monitored for visual signs of consciousness, heart rate, internal temperature, plasma stress and osmotic parameters, and muscle quality parameters. The findings revealed that electrical stunning, although inducing brief unconsciousness, did not sustain it long enough to be effectively combined with ice-slurry, resulting in stress responses and muscle quality parameters comparable to those observed in unstunned fish. In contrast, anaesthesia effectively reduced stress and improved meat quality. The ikejime technique, despite its labour-intensive nature, demonstrated significant advantages, including reduced physiological stress and superior muscle quality outcomes. These results suggest that the viability of electrical stunning as a humane option for industry implementation has important limitations, while ikejime, with further refinement and automation, could offer a humane and effective solution to optimise both animal welfare and meat quality in industrial settings.
歐盟指令和國際準則強調了人道屠宰做法的必要性，特別注意在屠宰前對魚類進行適當的電擊。本研究調查了電擊和屠宰方法的各種組合對地中海和黑海地區(qū)廣泛養(yǎng)殖的物種金魚鯛（Sparus aurata）福利的影響。具體而言，該研究探討了電擊、麻醉和非電擊，然后使用冰漿或ikejime（手持刺入工具）技術進行屠宰過程中，監(jiān)測魚類的意識視覺體征、心率、體溫、血漿壓力和滲透參數以及肌肉質量參數。研究結果表明，電擊雖然會導致短暫的昏迷，但并不能持續(xù)足夠長的時間，無法與冰漿有效結合，從而導致應激反應和肌肉質量參數與未經電擊的魚類相當。相比之下，麻醉有效地減輕了壓力，提高了肉質。盡管ikejime技術具有勞動密集型的性質，但它顯示出顯著的優(yōu)勢，包括減少生理壓力和提高肌肉質量。這些結果表明，電擊作為工業(yè)實施的人道選擇的可行性存在重大局限性，而ikejime通過進一步的改進和自動化，可以提供一種人道有效的解決方案，以優(yōu)化工業(yè)環(huán)境中的動物福利和肉類質量。
Keywords
Compassionate killing，Aquaculture Animal care，Unconsciousness，Alternative methods
