Document type: scientific article published in Animal Welfare
Authors: Lorenzo RA, Llonch P, González J, García del Arco JA, Font-i-Furnols M, Rotllant G.
Abstract in French (translation): Assessment of the impact of electrical stunning on the welfare and meat quality of the American lobster (Homarus americanus)
Sensitivity in decapod crustaceans has become a major issue in the field of animal welfare, partly due to the lack of legislation protecting their welfare, particularly at the time of slaughter. Electrical stunning has been shown to prevent or minimize pain and distress prior to slaughter. It is essential to study its effects on behavior, physiology, and meat quality to inform future legislation. This study evaluated the impact of electrical stunning using Crustastun™ on the American lobster (Homarus americanus) in order to: (i) determine the effect of two stunning durations (5 vs. 10 s) on recovery and behavior; (ii) assess the physiological alterations caused by stunning and observed during recovery; and (iii) evaluate the impacts on meat quality. Lobsters exhibited longer recovery times with 10-second stunning compared to 5-second stunning, as well as increased activity during recovery. Electrical stunning caused persistent disturbances in hemolymph glucose and lactate levels. Overall meat quality was not affected, with the exception of texture, which improved in stunned animals. Based on recovery, this study demonstrated the reversibility of Crustastun™, which distinguishes it from a terminal slaughter method. Stress induced by electrical stunning was evidenced by elevated lactate levels in the hemolymph, highlighting that this measure serves as an indicator of secondary stress responses. Reversibility implies that animals must be slaughtered before any signs of recovery appear, which, based on the righting response, should not occur more than 10 minutes after a short cycle and 40 minutes after a long cycle. However, the duration of unconsciousness should be confirmed using other indicators of consciousness, ideally based on neural activity.
Preview: Sentience in decapod Crustaceans has emerged as a major topic within animal welfare, partly due to a lack of legislation that protects their well-being, particularly at the moment of killing. Electrical stunning has been proven to prevent, or minimise, pain and distress prior to dispatch. Investigating its effects on behaviour, physiology, and meat quality is essential for informing future legislation. This study tested the impact of Crustastun™ electrical stunning on the American lobster (Homarus americanus) in order to: (i) determine the effect of two stunning durations (5 vs 10 s) on the recovery and behaviour; (ii) assess physiological alterations caused by stunning and during recovery; and (iii) evaluate impacts on meat quality. Lobsters showed longer righting times with 10 s stunning compared to 5 s, along with increased activity during recovery. Electrical stunning caused sustained disturbances in haemolymph glucose and lactate levels. Overall meat quality was unaffected, except texture, which was improved in stunned animals. Based on the recovery, this study demonstrated the reversibility of Crustastun™, distinguishing it from a terminal dispatch method. Stress induced by electrical stunning was evidenced by the elevated haemolymph lactate levels, highlighting this measure as an indicator of secondary stress responses. The reversibility implies that animals should be slaughtered before any signs of recovery which, based on the righting response, should be no later than 10 min after short and 40 min after long cycles. However, the duration of unconsciousness should be confirmed using other indicators of consciousness, ideally based on neural activity.
