Lyme disease would be a long shot. Other animals, primarily dogs, usually don't get the target lesion seen in people. Not sure that there is enough known of Lyme in cattle to say they do or don't develop one, but this looks more like a hair loss/epithelial skin cell lesion then a change of skin color. You could argue that maybe it is still anaplasmosis, but if your only evidence that it has a tick borne parasitic blood disease (anaplasmosis) is based on the fact that it looks similar to lesions seen in a tick borne bacterial infection (Lyme) in an entirely different species, then you can stretch your imagination farther than I can.
Treat it like ringworm and come back and curse me if it starts to get sore joints.