Cows show their affection for each other by licking each other's heads, shoulders and backs. Taking them away from their friends often makes them stressed and sad. It is not difficult for cows to recognize each other because voice and smell are not interchangeable. In addition, they are highly intelligent and can recognize as many as 100 other animals in a herd. Not only can they solve puzzles, but they also really enjoy it. Once they figure out how to open a gate with their heads, they jump in the air and let loose.