It would appear as though this is a universal issue as I have had it on pocket edition and have met people who've experienced it on win 10 as well. The sooner they fix this the better.
@aspergerian I interact with all my animals and the still deswawn. Even tamed horses with saddles and armor, but I am on the latest version of PE on single player.
I am having the same issue on IOS as well. It is so frustrating. It makes me not want to play the game for fear of the despawning.
I've had this issue on IOS as well.