The forced swim test, which has been carried out since the 1950s, is as cruel as it is worthless. Experimenters often dose mice, rats, guinea pigs, hamsters, or gerbils with a test substance and drop them into 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 start to float.
This absurd experiment is supposed to tell us something about the effectiveness of experimental antidepressant drugs in humans, based on how long the animals swim before floating.
But the test has been heavily criticized by 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.
Forcing animals to swim for their lives inside containers is a poor model for human mental health. These experiments do nothing more than terrify animals.
The test is so worthless that it is actually less predictive than a coin toss. This is what PETA scientist Dr. Emily Trunnell found after analyzing its use by major pharmaceutical companies. Her study was published in Drug Discovery Today.