Researchers trained an artificial intelligence (AI) algorithm with 7,414 recordings of pig noises, gathered throughout the life stages of 411 pigs – including slaughter. The algorithm could potentially be used to build an app for pig farmers that detects whether the animals are happy just from the noise they're making. As already revealed in previous research, there are more high-frequency calls from pigs (such as screams and squeals) in negative situations. At the same time, low-frequency calls (such as barks and grunts) occurred both in situations where the pigs experienced positive or negative emotions. With an even more thorough analysis...