I find it very despairing seeing animals locked up in a zoo! If only you had gone a little higher to see the despair on that tiger/lion's eyes... The post on the left you could have cropped out a little more as well. But otherwise a good photo, good luck.
It does seem cruel to hold them in cages, but when other humans care nothing of their habitat or importance, the despair of their existance really shows through. A good concept to capture but I don't think this photo truly shows it.
He's happy, entertains the visitors, doesn't have to hunt for a meal, ensures the survival of his species, and brings in money to the town. Nobody loses here. :)