It's probably sensitive or even painful in that area. He could have some sort of skin problem or something under his skin thats bothering him. Check his collar for rough edges/underside and if it persists take him to the vet.

No, thats not normal. Take him to a vet. I had a puppy several months ago who died of those and a few other symptoms. It could be due to a variety of health reasons including hereditary problems, organ failure, intestinal parasites, or even the dreaded disease: Parvo, which is highly contagious and very often … Read more