The variety of dog hair is vast, ranging from shaggy to short, curly to straight. If you have a dog, you’re familiar with the constant presence of their hair on your couch and in your clothes. But have you ever wondered why dogs have different coat types?
The differences in coat type can be attributed to their genes. There are three main features that determine a dog’s coat: the length of the hairs, whether they are curly or straight, and whether they have additional “furnishings” like a moustache or shaggy eyebrows.
These three features combine to create seven different coat types in dogs: short, wire, wire and curly, long, long with furnishings, curly, and curly with furnishings. Through a study of over 1,000 dogs, researchers have discovered that only three genes are responsible for the variety in coat types.
The gene responsible for long hair (FGF5) is recessive, meaning dogs must have two copies of the mutated gene to have long hair. Curly coats are related to a gene called KRT71, which affects keratin and is also found in cats with hairless or curly-haired breeds. The gene responsible for furnishings (RSPO2) is involved in establishing hair follicles.
While these three genes explain the majority of coat types in dogs, there are still some breeds, like the Afghan hound, whose long coat cannot be explained by these genes. Further research is needed to identify less common mutations and genes that control coat type in these dogs.
In addition to coat type, dog coats can also be single or double. Double-coated breeds, like Labradors, have a longer coarse layer of hairs and a softer and shorter undercoat. This double coat is a result of a mutation in chromosome 28 and was likely selected for in Labradors bred to retrieve fishing nets in Canada.
The type of coat a dog has is important, especially with climate change causing hotter temperatures. Dogs with double coats are less able to tolerate heat stress as their hair prevents heat loss. A study found that most breeds at higher risk of heat-related illness had double coats, with a death rate of 23%.
Grooming is also affected by a dog’s coat type. Dogs with long or curly hair with furnishings require more time and effort for grooming. Designer dogs, which are cross-breeds often mixed with a poodle, are likely to have curly coats with furnishings. Owners of designer dogs reported that grooming was more challenging than expected.
Proper grooming is essential for a dog’s well-being. If grooming is neglected, it can lead to welfare problems. Training dogs from an early age to enjoy being brushed can help prevent grooming difficulties. It’s also important to ensure their first experience at the groomer is positive to avoid future issues.
Regardless of a dog’s hair type, keeping them well-groomed is crucial for their comfort and overall happiness.
