Pigs' grunts reveal how they're feeling, new analysis says

Pigs' grunts reveal how they're feeling, new analysis says.

A database of thousands of grunts, oinks, snuffles and squeals, gathered and recorded from hundreds of pigs at every stage of their lives, will be used to help farmers better understand their animals' emotional states and improve their welfare in the future, according to a new study.

The researchers used an artificial intelligence system that determines with high accuracy whether the vocalizations made by pigs are expressions of positive or negative feelings, and even the circumstances where the sounds are made -- including situations such as nursing piglets, meeting their mothers or littermates, waiting around, being surprised, and huddling together.

"We decided to focus on pigs because they are very vocal," said animal behaviorist Elodie Briefer of the University of Copenhagen in Denmark, who co-led the study published last week in the journal Scientific Reports. "They grunt all the time."

It turns out that pigs are among the most talkative farm animals, so their vocalizations have often been studied to find out what they're saying.