Having grown up in a rural area I was always taught to have a very healthy respect for cattle. We were told never to enter a field of cattle (or horses for that matter) without carrying a decent size stick.
Watch any cattle farmer, they mostly all carry sticks
and it is not because they need to lean on them!
Basically waving a stick at an inquisitive cow can give it enough pause to allow you to carefully move away, as most cattle have met sticks and are a bit wary of them. You do not want to hit it, or challenge it at all. However a stick can work like an extension of your arm and keep it at a further distance.
I pick a stick from the hedgerow if I come across a field of cattle, and leave it at the other side of the field when I leave for someone else to carry.
Remember to check the ground every time you enter a new field. Fresh cow pats are the best indication there is cattle in the area.
In one area I walked, the farmer had made a few 10’ square enclosures along the side of the footpath every few hundred yards. I was puzzled about these, and it took me a while to realise they were almost certainly refuges which people could duck into if they felt worried by his cattle.