The Forced Swim Test (FST) is a behavioural test conducted on animals in laboratories around the world, including Australia. It involves the dropping of a mouse or a rat into a beaker of water to observe its ability to swim, unable to escape. At first, animals panic and 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, until eventually, they start to float.
The strength of the validity of the FST is now widely disputed. Instead of giving a true indication of mood or depression, the FST, in effect, really only records the time the animal takes to give up its struggle to swim to survive.