Thyroid diseases affect not only humans but also animals. They are increasingly being diagnosed in dogs, in which – as in humans – they can significantly impair the quality of life. Symptoms are not always specific and easy to recognise. Aware of this risk, a carer should keep a close eye on their pet and, if they notice anything worrying, consult a vet. Making a correct diagnosis and implementing appropriate treatment and management can quickly improve the well-being of the pet.
The thyroid gland in the dog is a small gland that is responsible for the production of two hormones that are extremely important for normal growth and development: thyroxine (T4) and triiodothyronine (T3). Their role is to regulate skin function and cell metabolic activity. Thyroid problems in the dog can have different origins and thyroid disorders can have different courses. Hyperthyroidism, i.e. the production of too many hormones, is possible. However, it is far more common to have hypothyroidism in the dog, a condition where there are too few hormones. It is worth noting that this is one of the most common endocrine diseases that occur in four-legged dogs.
Thyroid diseases in the dog and their causes
Hypothyroidism in the dog is a condition that is not yet well understood. The causes of its onset are not clear, although specialists cite several factors that may be relevant. In most cases, it is thought that the disease is a consequence of autoimmune lymphocytic thyroiditis, which leads to reduced hormone production. This form of the condition is called primary hypothyroidism and is by far the most common. It occurs mainly in middle-aged dogs. In addition to this, we can have congenital or central hypothyroidism. However, these forms are much rarer.
Currently, it is difficult to pinpoint why a dog’s thyroid gland is not working properly. However, it has been noted that the tendency to hypothyroidism is greater in some breeds than in others. Genetically predisposed breeds include Irish Setters, German Shepherds, Golden Retrievers, Labrador Retrievers, English Bulldogs, Newfoundlands, Bernese Mountain Dogs, Belgian Shepherds, Dachshunds, Schnauzers and several other breeds. Thyroid tumour, radiation, stress, poor air quality and inadequate diet are also cited as probable causes of the disease. Foods containing excessive amounts of cereals can be harmful. Therefore, a wet dog food composed of high-quality ingredients, chosen in the right proportions, plays a very important role in nutrition.
What are the symptoms of hypothyroidism in the dog?
Hypothyroidism in the dog affects the functioning of the entire body. Symptoms can be non-specific and vary in severity. Some are subtle and barely noticeable, while others are typical and easily recognisable by the vet, as well as the carer if he knows what to look out for. His vigilance should be aroused by an apathetic, sad dog. A lack of interest in the environment and an unwillingness to play are observed. Some of the most common symptoms are sluggishness and lack of energy. In addition, an increase in body weight while not giving more food happens. Discolouration of the skin, as well as a dulling and loss of the coat, may also indicate the disease. Characteristic is baldness on the sides of the body and on the tail, which is referred to as ‘rat tail’.
A diseased thyroid gland in a dog is very often diagnosed on the basis of dermatological problems. In addition to alopecia and dulling of the coat, skin thrush, abundant sebum production and excessive keratosis of the epidermis may occur. Other symptoms include a slowed heartbeat and reduced performance. Hypothyroidism in the dog can also lead to neurological symptoms. Sometimes there is atrophy of some facial muscles and drooping of the eyelids, and this gives the quadruped a ‘sad look’. Limb paresis, laryngeal paralysis and vestibular syndrome (head turning to one side, balance problems) also occur. In adults, decreased libido, impaired oestrus and infertility can occur. Conversely, congenital hypothyroidism in puppies can lead to dwarfism.
How to treat hypothyroidism in a pet?
Since a diseased thyroid gland in a dog does not always give clear and easily noticeable symptoms, it is worth remembering to systematically perform preventive blood tests on your pet. These should include a basic blood count as well as tests for thyroid disease. If it is confirmed that your pet is suffering from hypothyroidism, it will be necessary to introduce an appropriate feeding plan and drug therapy. As many pets suffering from this condition experience an increase in appetite, it is imperative to monitor food intake and weight gain.
The good news is that with the right treatment, the progression of the disease can be halted or even reversed and the quality of life significantly improved. However, it is important to remember that hypothyroidism in dogs is incurable. This, in turn, implies the need for constant medication, specifically thyroid hormones and sometimes iodine supplementation. What can be somewhat difficult and time-consuming is to select a dose of hormones that will ensure adequate levels in the body. Once this is done, however, we will notice a visible improvement in the dog. Importantly, with proper treatment, hypothyroid dogs can live long and happy lives. The therapy itself, on the other hand, has no negative side effects for them.
