New study reveals exactly how much pain fish feel when being killed and it's traumatizing people

Warning: This article contains discussions of animal cruelty which some readers may find distressing

A new study has revealed fish can experience intense pain when they're killed, and the heartbreaking fact is traumatizing people and likely making them consider vegetarianism.

While the suffering of animals sent to slaughter is well documented, with measures in place to try to make the process as 'humane' as possible, there's a silent suffering among fish where seemingly, the world turns a blind eye.

More than two trillion wild and farmed fish are caught and killed to feed the human race each and every year, according to Earth.com. Yet a lesser known fact is that the aquatic species suffer just as much as land animals do.

The outlet adds rainbow trout can suffer immensely when dying, from a 'prolonged and intense form of distress' when kicks in as they suffer air asphyxiation - the most common way they are killed.

Trout can suffer for a long time (Getty Images)

The insight comes from the journal Scientific Reports which reveals fish endure a slow and stressful decline once pulled from their habitat, prompting them to frantically gasp while oxygen disappears and carbon dioxide hikes up.

Shockingly, scientists say the fish could be in this panicked, painful state for as long as 25 minutes before reaching unconsciousness.

Of these 25 minutes, researchers estimate the average trout endures 10 solid minutes of pain that can be categorised as disabling, hurtful or excruciating.

To add to the trauma, death by air is the most common way fish are killed, and sometimes they're chilled in ice or a slurry which might sound kinder, but in reality may be delaying the loss of consciousness for even more agonising minutes.

The ice might be making things worse (Getty Images)

Exposure to the ice, even for fish that live in cold waters, can increase the extent of the suffering, risking tissue damage, thermal shock and prolonging fear - not to mention their transportation and cramming in alongside other panicked, gasping fish.

Dozens have since taken to Reddit to share their disgust at the unnecessary harm caused when fishing.

"Thats way more f**ked up than how we kill mammals and poultry," one comment read, as another said: "This is why I hate fishing. It’s just animal torture that’s treated as a fun activity."

"Letting fish flop around the deck until they slowly die, like they do on commercial fishing boats, has never passed the eye test for me," a third sympathetic person penned.

Meanwhile, scores of others suggested that killing the fish humanely would be in our best interests as consumers, too.

Many say they've been left traumatized by the thought (Getty Images)

"It’s wild because fish are so easy to humanely kill, and they taste better when done so," said one while another pointed out a theory that the fish taste worse when left in prolonged states of suffering.

Citing the verdict of a Japanese study, the Redditor said researchers discovered fish that were kept on a hook for hours 'had ridiculously elevated levels of stress hormones' that 'was evident in the taste,' concluding that fish should be killed as soon as possible.

Another said they had been on a sport fishing excursion and noted how the fishermen were 'diligent' about 'landing killing blows on the fish as soon as we reeled them into the boat'.

"It was violent but WAY more humane than letting the fish slowly die in pain," they added.

As per the study, it recommends electrical stunning to curb suffering, but even this method has setbacks.