“…Decreasing temperature and providing moderate amounts of carbon dioxide as an anesthesia prior to slaughter can reduce the stress to fish and improve muscle quality. Stunning larger fish with a blow to the head is effective, although some animal welfare advocates, out of ignorance, particularly in Europe, consider this to be cruel and are in favor of electroshock, which instead is a more stressful method even under the best of conditions for freshwater fish (Holiman & Reynolds, 2002), resulting in hemorrhaging, muscle bruising and gaping, and is clearly highly stressful for large marine fish such as tuna (Soto et al, 2006). In aquaculture, harvest techniques are generally less stressful than for wild harvest of the same species since capture occurs under conditions that are usually easier to control, although some stress always occurs.…”