FISH feel pain in a "strikingly similar" way to mammals including humans, a new study claims.

Injured fish will attempt to soothe their wounds, hyperventilate and even starve themselves due to pain, researchers say.

3 Injured fish feel pain and avoid damaging stimuli, a study reveals Credit: Getty - Contributor

The existence of pain in mammals is a long-known fact, and helped give rise to veganism and vegetarianism.

But many diets exclude meat but include fish, often due to a lack of evidence over whether fish feel pain.

Now a study claims that fish do feel pain in similar ways to mammals – including humans.

Fish given an electric shock in one part of the tank stopped feeding there, researchers from the University of Liverpool reported in the Philosophical Transactions of the Royal Society B journal.

3 People who fish should treat their catch more humanely, researchers now urge Credit: Alamy

The fish would refuse to feed for three days, effectively starving themselves.

Another type of fish called a perch would not feed as frequently after its mouth had been damaged by a fishing hook.

This indicates that the fish had been hurt by the injury.

Other fish were documented hyperventilating, waving their injury tails and rubbing parts of their body after an injury.

Now experts say fish should be treated more humanely.

This includes using less damaging hooks to catch fish, and killing fish more quickly after being caught, researchers say.

"When subject to a potentially painful event, fishes show adverse changes in behaviour such as suspension of feeding and reduced activity, which are prevented when a pain-relieving drug is provided," said Dr Lynne Sneddon, of the University of Liverpool.

"When the fish's lips are given a painful stimulus, they rub the mouth against the side of the tank – much like we rub our toe when we stub it.

"If we accept fish experience pain, then this has important implications for how we treat them.

"Care should be taken when handling fish to avoid damaging their sensitive skin.

"And they should be humanely caught and killed."

Pain – the simple facts Here's what you need to know... Pain is defined as a feeling of distress caused by "an intense or damaging stimuli"

In medicine, pain is seen as a symptom of a condition – rather than being a condition itself

Although pain is uncomfortable, it works as a self-preservation tool

It motivates humans to withdraw themselves from damaging situations

It also works as an incentive to protect damaged areas of your body while they heal

And it acts as a deterrent, helping you avoid damaging experiences in the future

Pain generally stops once the underlying cause is removed. However, sometimes pain can be present even when detectable stimuli are absent

3 Peta director Elisa Allen said the news makes it 'harder for humans to justify sticking a fork' in fish Credit: PETA

Scientists believe that almost all animals can detect when they've been injured.

But there has been uncertainty around whether fish feel pain, because they have a much simpler brain.

So researchers examined decision-making and behaviour after injuries – and used painkillers in an attempt to "fix" this.

For instance, zebrafish exposed to hot temperates wouldn't swim as far. But this behaviour changed after morphine was introduced to the water.

Also, zebfafish and trout reacted in similar ways to acidic chemicals that create a burning sensation.

"Anyone who has seen fish gasping for air while trapped in a trawler's net, impaled at the end of a line, or floundering on the deck of a boat is sure to recognise that these animals experience fear, pain, and distress – just like humans do," said Peta director Elisa Allen, in a statement given to The Sun.

"Fish are intelligent, have unique personalities, and value their own lives, and the more we learn about these fascinating animals, the harder it is for humans to justify sticking a fork in them.

"Renowned marine biologist Sylvia Earle said, 'I wouldn't deliberately eat a grouper any more than I'd eat a cocker spaniel. They're so good-natured, so curious.'

"Delicious fish-free fish fingers, faux fishcakes and even vegan prawns are all readily available.

"And not only are these better for animals and the world's oceans, they also offer all the taste but none of the toxins or cholesterol found in cruelly obtained fish flesh."

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Do you ever think about animal suffering when eating meat or fish? Is it important to you? Let us know in the comments.

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