Outstanding in her field

I saw something odd in a field. It stood out because of color, but it was still odd. I had to see it in flashes, for I was driving, but it wasn't clear to be either a cow or a trough. At the last glance, it turned its head -- a cow, out alone, quarter to half mile from any building. There were no other cows. I'm not sure it was a "happy cow", but it was outstanding in its field.