The Forced Swim Test: A Cruel, Ineffective Experiment in Which Small Animals Are Trapped in Beakers of Water Until They Stop Swimming

The forced swim test is a widely used experiment that’s as cruel as it is worthless. In this test, experimenters put mice, rats, guinea pigs, hamsters, or gerbils in inescapable containers filled with water. The panicked animals try to escape by attempting to climb up the sides of the beakers or even diving underwater in search of an exit. They paddle furiously, desperately trying to keep their heads above water. Eventually, they’ll start to float.

Some form of this test has been carried out since at least the 1950s, when notorious Johns Hopkins University experimenter Curt Richter forced rats to swim in cylinders of water until they drowned. It was popularised in 1977 by an experimenter named Roger Porsolt, who called it the "behavioral despair test". Porsolt found that rats who'd been given human antidepressant drugs would struggle and swim for longer than other rats before starting to float, and he concluded that those who swam for less time were in a state of "despair". But the test has been heavily criticised by other scientists who argue that floating is not a sign of despair but rather a positive sign of learning, conserving energy, and adapting to a new environment.

More than 40 years later, in university and pharmaceutical laboratories, animals are being dosed with drugs and then dropped into cylinders of water so that experimenters can measure how long they struggle.

The forced swim test doesn’t accurately predict whether a drug will work as a human antidepressant. It yields positive results for compounds that aren’t prescribed as human antidepressants, such as caffeine, and negative results for compounds that are. Importantly, antidepressant compounds that might work in humans may be mistakenly abandoned based on the test.

The bottom line is that the forced swim test is bad science. These experiments do nothing more than terrify animals and delay the development of new effective treatments that are so desperately needed.

After hearing from PETA entities and kind supporters like you, government agencies, universities, and many of the world’s top pharmaceutical companies have pledged not to permit, conduct, or fund the forced swim test. It’s time for India to reaffirm its role as a world leader in biomedical research and regulatory testing by shifting away from failed, cruel experiments on animals and embracing human-relevant models that will bring desperately needed treatments, cures, and vaccines.

Take action and please sign our petition to show your support for the Research Modernisation Deal and request to establish a clear policy mandating an end to animal experimentation and provide a strategy and timeline for achieving this goal.

Help Stop These Cruel Tests

Appeal:

I was horrified to learn that your company hasn't officially implemented a policy against using the notorious forced swim test – also known as "the behavioral despair test" – to test potential antidepressant drugs. It involves placing animals in an inescapable cylinder of water and forcing them to swim until they're near drowning. They try to escape by attempting to climb up the steep sides of the beaker and diving underwater to look for an escape route. They paddle furiously, until they eventually float.

The forced swim test is mired in scientific controversy as well. While some interpret the animal's floating behaviour as despair or depression, others believe that it indicates an adaptive survival strategy. Importantly, your company's use of the test hasn't helped you produce any new, approved antidepressant treatments for humans.

I urge you to ban the use of the cruel and worthless forced swim test. 

Sincerely,

[Your Signature]

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