Hair and fur consist of keratin, which is the same structural protein that creates skin and nails. The scientific term for the wooly or hairy covering of mammals is pelage, and science makes no distinction between hair and fur – both are simply pelage.
More detailed descriptions are meaningful to groomers, breeders, and dog show judges. Terms like “hair” and “fur” are widely accepted.
The hairs in undetermined length (UDL) coats grow until they break or are cut. In his book, Happy Dog (New American Library, 2009) celebrity dog groomer Billy Rafferty helped popularize UDL breeds as “hair dogs.” Examples include Afghan Hounds, Cairn Terriers, Maltese, Irish Terriers, and Poodles.
Pre-determined length (PDL) coats grow to a certain length and stop. Rafferty calls PDL breeds “fur dogs,” and they include Beagles, Boxers, Jack Russel Terriers, Labrador Retrievers, Rottweilers, and Weimaraners.
His third category, “multi-length fur breeds,” describes dogs with both UDL and PDL traits. Examples include Alaskan Malamutes, Border Collies, Cavalier King Charles Spaniels, Golden Retriever, Newfoundlands, and Great Pyrenees.
Hair is usually described as longer, finer, often wavy or curly, and has a longer growth cycle, while fur is described as shorter, denser, and has a shorter growth cycle, resulting in more frequent shedding. Your groomer can describe your dog’s coat in detail and explain which grooming products and methods will work best for its length, growth rate, texture, and shape.
For example, hair dogs like Poodles require monthly or bimonthly haircuts, while short-haired fur dogs like Labrador Retrievers don’t need much more than frequent brushing and occasional baths.
Hair dogs may produce less dander and shed less than fur dogs but hair coats can mat and tangle more, requiring conditioning and detangling, while many fur dogs benefit from de-shedding treatments.