Cachexia in dogs is severe loss of body weight, fat, and muscle. It can be caused by various causes, which are characterized by producing a negative energy balance in the animal. To correct cachexia, it is necessary to make a diagnosis of the specific cause that produces it and establish a specific treatment that allows correcting the energy deficit and favors the animal's weight gain.
What is cachexia in dogs?
Cachexia consists of the severe loss of body weight, fat and muscle. It is a syndrome (set of clinical signs) that can appear associated with various pathologies, which have in common to cause a negative energy balance.
When, for reasons that we will explain later, an animal enters an energy deficit, it begins to consume the glycogen that is in the storage or reserve organs (liver and muscle). These deposits are limited and provide energy for 2 or 3 days. After this time, the body begins to metabolize the fat (subcutaneous and abdominal) and, when it has been consumed, it catabolizes the proteins (first the muscle proteins and then the glandular tissues).
Types of cachexia in dogs
There are some types of cachexia that are associated with specific pathologies, which is why they are known by a “proper name”. The best known are:
- Cardiac cachexia: consists of weight loss in dogs with Congestive Heart Failure (CHF). In these patients, energy consumption increases as a consequence of sympathetic activation, increased work of breathing and tachycardia.
- Tumor cachexia: consists of weight loss as a consequence of the development of a tumour. In cancer patients, there is an increase in basal metabolism because the tumor requires a lot of energy to grow, which is why it rapidly metabolizes carbohydrates and proteins. In addition, many cancer patients receive chemotherapy, which contributes to weight loss.
However, there are many other causes that can cause cachexia, which we explain below.
Causes of cachexia in dogs
The causes that cause cachexia in dogs include those that involve an insufficient intake of nutrients, those that involve an increase in energy requirements and those that involve a loss of nutrients (digestive, urinary, etc.). Next, we detail the main causes of cachexia in dogs:
- Anorexia: Although anorexia (complete loss of appetite) seems to be more a consequence of cachexia than a cause, it is true that In cachectic animals, a positive feedback loop occurs between the progressive weakening and the lack of appetite, so that they aggravate each other. That is, cachexia causes anorexia, and vice versa. If you want to read more about Anorexia in dogs, we recommend that you take a look at this article on our site.
- Deficiency diets: they lead to an insufficient intake of nutrients that leads to a negative energy balance maintained over time.
- Increased Basal Metabolic Rate: Occurs in fever, infectious diseases, trauma, and tumors. In the case of tumors, we speak of "tumor cachexia". You can learn more about tumors in dogs, here.
- Congestive Heart Failure (CHF): in patients with heart failure there is an increase in energy requirements due to activation of the Sympathetic Nervous System, increased work of breathing and tachycardia. In these cases, we often refer to the cachexia as “cardiac cachexia.”
- Malabsorption syndrome: can appear in infectious and parasitic diseases, neoplasms, inflammatory processes (enteritis), lymphagiectasias and intestinal obstructions. In all these cases, the digestion of food is carried out correctly, but there is an alteration in the absorption of nutrients, which causes nutritional deficiencies and significant weight loss.
- Nutrient loss: it can be the loss of glucose in the urine in diabetes, the loss of protein in the urine in kidney disease or the loss of proteins through the digestive system in enteropathies, in major burns or in massive digestive parasites, for example.
Consequences of cachexia in dogs
Some of the consequences of cachexia in dogs are related to different apparatus and body systems such as:
- The musculoskeletal system: since muscle proteins are catabolized.
- The reproductive system: There are alterations in spermiogenesis (sperm production) in dogs and in the estrous cycle in bitches. In case of pregnancy, miscarriages frequently occur.
- The immune system: There is both cellular and humoral-based immunosuppression.
- Blood: Decreases hematopoiesis (production of blood cells) and plasma proteins.
- The digestive system: there is a progressive atrophy of the intestinal mucosa that gives rise to a malabsorption syndrome. Consequently, a picture of diarrhea appears that aggravates the cachexia.
Also, if it is young animals, the growth rate will decrease. In the case of cachectic animals that must undergo surgery, we must also consider that the level of tissue regeneration will be decreased.
Diagnosis of cachexia in dogs
When severe weight loss is detected, we should first check if there is a decrease in appetite or if the appetite is normal In case the appetite is decreased (hyporexia or anorexia), we will have to determine the cause of the anorexia. If the appetite remains normal, the animal's ration should be reviewed since the cause of cachexia may be a deficient diet.
If the diet is correct, we must direct the list of differential diagnoses towards those processes that can cause an increase in the metabolic rate or a loss of nutrients by some means. In any case, the person who will make this diagnosis will be the veterinarian that we go to as soon as possible. This will involve carrying out a diagnostic protocol which must include:
- A detailed history.
- A complete physical examination: in which special attention should be paid to the animal's body condition.
- Carrying out complementary diagnostic tests: depending on the list of differential diagnoses that we have prepared based on the anamnesis and physical examination, laboratory tests may be carried out (such as blood and/or urine tests, coprology, cytology, etc.) and diagnostic imaging tests (X-ray, ultrasound, CT or MRI).
In any case, it is important that our veterinarian make an early diagnosis to improve the prognosis and the effectiveness of the treatment.
Treatment for cachexia in dogs
The treatment of cachexia in dogs will depend directly on the cause that is originating it. In this sense, we can differentiate three types of treatment:
- In the event of anorexia: a treatment must be instituted depending on the cause of the anorexia.
- In case of deficiency diets: it will be necessary to establish a diet according to the nutritional and energy needs of our dog, taking into account the age, physical activity and physiological status. In this case, it will be especially important to consult a veterinarian specialized in animal nutrition, to guarantee a he althy, complete and balanced diet for our dog.
- In the case of pathologies: that cause an increase in metabolic expenditure or a loss of nutrients by some means, treatment must be instituted specific to the pathology in question.
