Cattle appear to be rather static animals from the car window, but a few minutes’ observation reveals that grazing demands a lot of activity and movement from the cow. Grazing cattle constantly swing their heads and necks from one side to the other as they crop the grass in a swath, and are always moving forward, slowly but surely. As their weight shifts forward they move each of their four legs in turn. This constant movement means that spatial arrangements of the parts of the cow are always reconfiguring themselves and this presents a constantly-changing motif to the painter.
One approach to solving this difficulty is to take a photograph of the cow, thereby fixing its position in an image, and then to paint from the photograph. I think this is a mistake. Painting a cow, and painting a photograph of a cow are two completely different activities. I don’t see how the products cannot be completely different either. Patience and careful observation are the remedy for the problems of drawing cattle.