Document type: Article published in Agri Hebdo (Switzerland)
Author: ATS with AFP
Preview: Listen to your pig: In an effort to improve animal welfare, European researchers have developed a tool to decode the feelings expressed by pigs in their various grunts.
Split between Switzerland, Denmark, Norway, France and the Czech Republic, biologists studied more than 7,000 recordings from 411 pigs, from the brief squeak of satisfaction at feeding time to the desperate cries at slaughter, before classifying them into nineteen different categories.
"We show that it is possible to determine the emotions of pigs according to their vocalizations," explains to AFP the project leader Elodie Briefer, senior lecturer at the University of Copenhagen.
Measuring mental health
Thestudy, published in the journal Nature, offers a new avenue for improving animal welfare with a tool to categorize an emotion through the noise produced, according to the researcher.
"We also use a machine learning algorithm (...) that produces a spectrogram and trains to recognize negative and positive contexts," she says.
Once developed, this new type of monitoring will allow farmers, who only have tools on physical well-being, to ensure the mental health of their animals.
"If the percentage of negative sounds increases, then the farmer knows that something is probably wrong and can go and check on the pigs," says the researcher.
For the Danish Board of Agriculture - the Scandinavian country is home to 13.2 million pigs, a European record of more than 2 pigs per capita - the implications of the study are promising.
"This concept...could potentially be one useful tool among others in the work of monitoring the health and welfare of pigs," says Trine Vig, a spokeswoman for the council.
According to Briefer, "we achieve 92% accuracy in classifying valence, i.e., determining whether the call is negative or positive, and 82% accuracy in classifying the actual context in which the sounds were produced."
Very vocal pigs
According to the study's findings, positive feelings are expressed in short sounds while negative thoughts are most often expressed at length.
But why focus on the pig rather than the calf or the rabbit? For the study's authors, the pig, known for its wide range of squeaks and noises, was the perfect stud.
"They are very vocal, which makes them easy to study (...) they produce vocalizations all the time. Even in low-intensity situations, they continue to vocalize," the academic points out.
