Taming a ocelot to make a cat give hearts every fish and they won't.....

I got some ocelots in a 7x7 pen got some fish tryed to tame one it took the fish had hearts flying off it, it would not take a new fish till hearts go away. It took over 30 fish before it changed to a cat. ocelot 2 took a hole stack of 64 so far still feeding it.
I expected they would take a fish every time I clicked on them then have hearts fly off when changed to a cat, not take forever to feed and change. And take so many fish to turn to a cat. have not tryed the dogs yet.

edit: now it works fine can not duplicate. change to a glich?