The skin can show abnormalities caused by a variety of causes. Unfortunately, the signs are often non-specific to the cause. Abnormalities include hair loss, itching, spots, red areas and flaking to name a few common signs seen. Beagles can be affected as commonly as many other breeds with skin problems. As a breed, there can be allergy issues and hypothyroidism running in some families.
Some skin conditions are curable as they are caused by external factors which can be removed such as fleas and mites. Parasites cause itching and irritation and if they are dealt with the dog will stop scratching and the skin will return to normal.
Other skin conditions are treatable but it is more a question of controlling the underlying cause as they cannot be cured.
Investigation of skin signs involves the vet taking a good history from the owner and examining the dog carefully to see if there are any obvious causes. Very often it will be a question of working through a list of common causes and if they are eliminated then testing may be required for less common causes.
The most common causes of itching are external parasites, allergies and hormone imbalances. Even if there are no obvious signs of parasites like fleas for dogs with recurrent skin lesions it is a good idea to have a good parasite control regime as they are often sensitive to flea saliva.
There are various hormones that are involved in skin quality and an imbalance of levels causes problems. The thyroid gland can become underactive for various reasons, one common one is caused by the body developing antibodies that significantly reduce the hormone levels. Dogs with hypothyroidism gain weight, lose hair and look in poor condition. Is condition is not curable and can be easily managed with thyroid supplements.
Other hormone conditions include Cushing disease which will be discussed in more detail elsewhere.
Allergy problems are very common in the canine population. They can be caused by several different triggers and all produce the same symptoms of itching and hair loss. It may take a while to work through the list of possibilities. Food sensitivities can be eliminated by 4-6 weeks of a so-called novel diet such as rabbit or venison and potato. It needs to be done with no other food or titbits eaten at all during that time.
If that makes no difference to the dog then other causes will need to be checked out. Common non-food triggers are house dust mites, biscuit mites and pollens. It may be possible to develop a vaccine to help immunise against these.
Skin problems can be hereditary and it is wise to think carefully about breeding from dogs with repeated skin issues.