Fish are vertebrates, just like humans and many other animals. Like humans, they have a well-developed central nervous system and brains which regulate and register fear and pain. In experiments, fish have been shown to respond to negative stimuli so we know that fish suffer when they are placed on ice when alive or are removed from the water. Just like any animal in the food industry, fish deserve the least stressful and painful, and the most humane method of slaughter.
HOW FISH ARE TREATED
Most people still believe that fish do not feel fear and pain. We now know that this is not true. Nevertheless, fish are treated badly, from the capture methods at sea to the treatment they receive on fishing vessels. Thrown about on board they are then put on ice and slowly asphyxiate to death in extreme stress and pain. Scientific findings published in Worse things happen at sea: the welfare of wild-caught fish (2010) estimate that, depending on the species, fish take between 55 and 250 minutes to lose consciousness during which they feel pain and fear and are aware of their surroundings. Research is currently underway to find more humane methods of slaughter.
ANIMAL WELFARE ON YOUR PLATE
The debate about the environmental impact of the meat industry has grown over the last few years. More and more people are starting to realise the meat industry’s ecological impact. The media and various campaigns are drawing attention to this issue, as are international celebrities. They all plea for reducing meat consumption and all provide healthy, environmentally friendly, alternatives.
These days, food is more than what is on your plate. Food has become a concept that includes ethics, the environment and nature. But this concept is largely restricted to terrestrial animals. Marine animals need to be included in this picture as the issues are the same as with terrestrial animals – animal welfare, contamination of meat, climate change, species extinction. Fortunately, conservation and animal welfare agencies are starting to have an impact.
NEUROANATOMY: the BASICS
All vertebrates such as mammals, birds and fish have the same general brain structure. Like the others, fish have a forebrain, midbrain and hindbrain. The only difference between fish and other vertebrates is that their brains are smaller in relation to their body size and the structure is less complex.
Mammals’ cerebral cortex has six layers, of which the neocortex is associated with higher functions such as sensory perception and awareness. Because fish do not have a neocortex, it is assumed that they are unable to feel pain. But the Panel on Animal Health and Welfare contradicts this as one brain function can be performed by different structures in different families of animals. For example, birds and fish process visual stimuli differently. Equally, dolphin brains work completely differently from primate brains while they both have great cognitive abilities.
It can thus be assumed that fish brains have developed ‘functional analogue’ structures which, like higher order vertebrates, regulate fear and pain. Analog organs perform the same functions, and they have been found in fish. Tests show that parts of the brain of certain fish species react when the fish receive pain triggers, and structures in the forebrain of bony fish have the same function as the amygdala and hippocampus in mammals which are related to emotions, fear and memory.
Similarly, fish too have a thalamus, which receives information from the sensory organs and transmits it to the cerebral cortex. It is an important node in the brain that all vertebrates have and which makes them aware of their surroundings and what happens to them.
As the study of fish brains is so recent, there is still so much to discover and it means that some researchers are sceptical about the findings to date. Much of their scepticisms rests on what ‘pain’ actually is. They believe that responding to stimuli is purely nociception – an automatic, unconscious response rather than pain. In contrast, the International Association for the Study of Pain defines pain as ‘a conscious sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage’.
To draw a parallel, how can we scientifically prove that human foetuses experience pain in the womb? There was a time when foetuses and newly born babies underwent medical treatment without anaesthetics because their experience to pain was not proved beyond a doubt. We now think differently and take precautionary measures just in case babies do feel pain. Should we not take the same precautionary measures in the fishing industry?
Text: Danny Haelewaters
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- Ethisch Vegetarisch Alternatief (EVA) vzw