A dog's collar is as important as a person's clothing. Neither should leave home without wearing it. The pet identification, dog license number and rabies vaccination data on a dog's collar could save a pet's life or bring a lost dog home quickly. And whether a dog is on or off leash, its owner has better control of it when the dog wears a collar. Yet sometimes a dog's collar can cause problems --- most commonly, hair loss around the neck. A careful consideration of the type of collar used, and how it's used, can help prevent this from occurring.
Check your dog's collar for a proper fit. A collar that is too loose or too tight may cause friction or irritation that can trigger hair loss, especially if a dog has sensitive skin. Two fingers' length is the proper gap between your dog's neck and collar. Don't keep it any tighter, unless there's danger of the dog's head slipping out.
Choose a collar made from a material not likely to cause allergic skin reactions. Keep in mind that any part of the collar could cause contact dermatitis, which often results in hair loss. Metals such as nickel; materials like rubber, plastic or wool; or any materials containing certain chemical dyes can cause a reaction.
Try using a rolled leather collar with a smooth lining. In addition to a properly fitted collar, one with a rolled shape could cut down on friction that causes hair loss around the neck.
Improve your dog's diet for better nutrition. Consult with your dog's veterinarian for guidance. Some types of hair loss result from improper nutrition and can manifest on a dog's neck, where collars chafe.