You can lead a horse to water and, it turns out, convince it to drink if the reward is great enough, researchers have found.
A new study has suggested horses are more intelligent than previously thought, having been observed to quickly adapt to a treat-based game with changing rules.
Researchers from Nottingham Trent University (NTU) said they were surprised by how the horses quickly grasped the game, busting previous theories that equine brains respond only to immediate stimuli and are not complex enough to strategise.
“This teaches us that we shouldn’t make assumptions about animal intelligence or sentience based on whether they are ‘built’ just like us,” she said.
If I remember correctly, play in both juvenile animals and humans is primarily about practicing for adulthood in all sorts of ways. Making it enjoyable is obviously of an evolutionary benefit. Like you said- puppies clearly enjoy playing, as do adult dogs since they have been bred to retain juvenile wolf features, and wolf pups also enjoy playing, but stop when they become adults.