A subtle white "line" can be seen when a wolf is sitting

If you get close enough to it and pay attention you will see a white "line" on his texture, look:

There is a whole white section on the texture that look like a box, it can be seen clearly on spectator mode. Video showing the bug by GonzoStudioz:

Steps to reproduce:

1. Spawn or find a wolf

2. Tame the wolf

3. Make the wolf sit

4. Spectator mode makes it easier to see it