Oh yes this is ringworm, we get it a lot in our parts due to the mild damp seasons we have here with a ton of rain. We deal with it every year. You should treat him with a pour on dewormer. When it gets this bad, because this is actually a pretty bad case, I actually put used motor oil on the spots to suffocate it. You can google about it. You'll read mixed reviews but our old vet swore by it and it works. With a mix of dewormer, oil on the spots and keeping him dry and letting this dry out it will clear up. If you have any other cows around him, they probably have it to. You have to treat your whole herd.