Animals can traspass stone walls.

I have a little space for some cows and sheeps.

As you know, animals can push each other.

So, if one of them is in the corner of the room, and then, another animal go to the same corner, the first one is going through the stone wall.

This doesn't happen with fences.

For the pictures I have used more animals, but with less than 0,25animals per square block you can get this bug. (I mean, with 6 animals in 5x5 room it will happen)

I have browsed for this bug, and I didn't found it, but if it's duplicated, I'm sorry.