I heard a story about a vegan household that kept pets. They tried to keep their cat on a vegan diet and didn't realize they need tuarine to survive. The cat was going bald and blind from lack of proper nutrition. They kept birds as well. The cat got the bright idea to eat one of the birds, the owners, sat it down and lectured it, telling it that it needed to live in harmony with its "brother" bird...
People need to understand that when you take an animal from the wild, or take on the responsibility of caring for an animal. You take on the role that of Caretaker and in a way, "god". You need to ensure it has all it needs to be happy, healthy.
IF a person cannot do that, or will not do that... they should not keep any thing live but themselves.
Carol