NEW Scots research shows that eating is an emotional and social process for rats, as they produce high pitched chirping sounds when feeding themselves.
The study was conducted by Scotland’s Rural College (SRUC) and laboratories from the French National Research Institute for Agriculture, Food and the Environment (INRAE), and published in the journal Frontiers in Behavioral Neuroscience.
The aim of the research is to measure behavioural diversity in rats and improve their welfare, as well as look into their inner emotional life to gain an understanding of how they feel about eating.
This is the first time scientists measured a specific type of ultrasonic vocalisations (USV) – high pitched sound produced by rodents – associated with the act of eating.
Previous studies have found that rats produce USVs during a positive emotional experience and when communicating with other rats.
This time, researchers recorded the rodents using an ultrasonic microphone when they were given a meal at the start of their activity phase, which is the equivalent of our breakfast.
Using audio editing software to transform the USVs into sounds audible to humans, the researchers found the rats were producing a new type of USV – a flat 40kHz frequency – when chewing their food pellets.
Vincent Bombail, SRUC Research Fellow Vincent Bombail, says: “The fact that rats chirp with their mouths full makes us realise feeding is more than about just filling their stomachs – it is also an emotional and social experience, even for laboratory animals.
“Just as we have our dinner table conversations, rats are also communicating something when they eat.”
