Earlier this year the farm by the approach track to Beinn a'Chochuill and Beinn Eunaich near Dalmally grazed some rather protective cows in a section of lower ground that needed crossed. Being springtime, there were a good few calves being supervised by some fiesty, full grown cattle. Opening the gate, I alerted the cows to my presence. My dog was kept on his lead and walked by my side furthest from the cattle. In my other hand I had extended a walking pole and held it low and wide, tapping the ground and speaking to the cows in a calm but confident manner helping them see I was not a threat. I gave them as wide a berth as possible, making sure not to walk near any of the youngsters. Things would have been made far easier had the farmer not placed a circular feeding cage right upon the track, a few cows considered mobbing us but were content to see me walk in the opposite direction. We made it past unscathed, and on the way back out at the end of our walk they seemed quite unfazed by our presence.
I'd agree that once under attack it's common sense to drop the dog's lead, but until such time the handler should keep control of their dog using the lead. A dog running free around cattle is only going to trigger an offensive reaction from those with young to protect.
Other areas where cows are an obstacle, are the approach roads to Beinn Bhuidhe near Loch Fyne and at Kenknock Farm, Glen Lochy. Also the stretch of the WHW between Falls of Falloch and Crianlarich has some defensive cattle to contend with.
At Beinn Bhuidhe they are Highland Cattle which in my experience seem more docile than the shorter coated roan cattle at Dalmally.
Thankfully, the Dalmally cows have recently been relocated and the short section of gated pasture is now open to the hillside.