While playing, I realized that I cannot feed most animals I encounter.  Most Recently, I have attempted to breed Pandas. I have found that about 1 in every 4 can even be fed.  The issue applies to all other animals in my world, including: Mooshrooms, turtles, cats, dogs, and villagers.  All other requirements are met. 

Two additional notes which may relate: 

1) cats and dogs can not be interacted with in any way. (no sitting, attacking or following is working, it's like they are not even there)

2) Animals tamed from the wild will not follow, this applies to parrots and Ocelots/cats.