Rat tickling improves animal welfare, gets rats used to handling, and creates a bond between people and rats. It also calms rats down and helps them get through stressful situations. Labs tickle rats to improve experimental validity and animal welfare. A rat that has been tickled for at least 3 days will be used to human touch, and understand humans to be fun friends. So, when a rat needs an injection or some other form of experimental manipulation, it doesn’t get as stressed out by it. As part of My rat tickling certification, I saw the difference in how a tickled rat and a non-tickled rat respond to receiving injections. The non-tickled rat was freaked out, it was reacting like it was in pain, and afterwards it looked quite stressed. The rat that got tickled and then given the injection was relaxed, mostly happy, and after being put back in its enclosure, immediately went back to exploring. Rat tickling is also a great way to produce 50hz vocalisations, which are the most accurate measure of rat happiness. So if your experiment is investigating animal welfare, you can use tickling and vocalisations as your dependent variable. For example, you might be testing an antidepressant on depressed rats. You want to know how effective the antidepressant is, so after dosing the rat, you tickle it and count its giggles. A happy rat will giggle more.