Horses and Loading Chunks

When riding a horse the world loads much slower and oftentimes will freeze (My horse and I can move but no other entities move and no chunks load). I have to go back some ways before the world works like normal. I have a map out and it does not update properly when this happens (either my marker does not move, or it does but no terrain loads).

I cannot dismount my horse when the world freezes like this. If I leave the game and rejoin, I am in a different area I had been in previously (I'm assuming the last place it saved before the world froze) and my horse is nowhere to be seen.