Tony
If you check my first post on this thread, you will notice I mentioned it is probably natural hoof trimming. Looks like my diagnosis was correct.
Now a small piece of advice.
For folks new to cattle, or those who have very few and tend to hover over them like a mother hen - everything about them is noticed and noted and often worried about.
One must remember these animals have literally 100's of thousands of generations of development. Unless there is dramatic pain or very obviously some difficulty - it is often worthwhile to relax and let Mother Nature help things along.
Cattle are not only a tough critter when speaking in general terms, they are quite able to look after themselves. Very often it is us and our handling that gets them all discombobulated.
Enjoy your animals and let them do the work - it really reduces the stress levels.
Take care,
Bez