I agree. This most likely isn't her first go around with wolves. I'm thinking She must be an old Cow, look how long her head is!
I have 3 photos. The first the calf was behind the small pine and the last pic the cow was half out of the screen heading into the water. I'm guessing the wolf lost them once they were in the water. It's a corner of a lake so they may have swam for a while and I'm sure they can swim much faster than the wolf.