Hair loss in dogs is nothing to worry about. In fact, it is completely normal that old hair sheds and gets replaced by newly grown hair. Many dogs lose lots of hair all throughout the year. The reason for this is that lots of dogs sleep indoors, where it is always warm and they therefore do not need an extra-thick coat. The shedding is determined by hormones, and these in turn are stimulated by the external temperature and light intensity. And with dogs that stay mostly indoors their hormones don´t register the decrease of the temperatures or the light intensity in autumn. As a consequence, dogs lose hair all over the year. But that’s no reason for concern.
Nevertheless, you should always have an eye open to check your dog´s fur and skin conditions. Is the skin rough and dull? Is the skin reddened or itchy? Is there any dog dandruff, eczema, or bald spots? If there are any of these symptoms, the veterinarian should be consulted.
The veterinarian usually investigates if there are any dog parasites, because hair loss and other dog skin problems are often caused by ectoparasites. Sometimes even parasites inside your dog’s body may be responsible for your dog´s hair loss.
Endocrine and metabolic disorders are some other common causes of hair loss. Bitches often shed after the birth of their puppies, whereas male dogs often lose lots of hair after castration. These conditions usually return to normal again soon after.
If your dog has severe hair loss with an unknown cause, the veterinarian will probably check the thyroid and kidney function, as diseases of these organs could potentially be the reason. Diseases of the gastrointestinal tract can result in the fact that certain nutrients are not absorbed or utilized. So, the dog might suffer from deficiency symptoms.
Actually, the most common causes of hair loss are allergies. More and more dogs are particularly affected by food allergies. In this case only a change of nutrition will make a difference.
Hair loss in dogs can also have psychological causes: stressed dogs often react not only with hair loss, but also exhibit a compulsive grooming behavior. This in turn can lead to irritated skin or skin eczema.