Failure to Gain Weight in a Canine

Failure to gain weight can be the symptom of a serious problem in both puppies and adult dogs. While an overweight dog isn't healthy, being underweight can present a number of health problems as well. The problem sometimes can be corrected with veterinary care and medication, so a proper diagnosis can return the pet to a healthy, thriving dog.

  1. Infectious Causes

    • Failure to gain weight can be evident when a sick puppy is surrounded by healthy siblings.

      When very young puppies -- less than a month old -- show signs of failing to gain weight, this is also known as fading puppy syndrome or failure to thrive. Unfortunately, this can be fatal when it strikes puppies, as it is often accompanied by other problems such as continuous crying and withdrawing from their mother and siblings. There are several different causes for this -- they could have a bacterial infection or virus that they contracted from their mother while still developing, or it may be the result of a genetic flaw. In all situations, the puppy will clearly be developing at a much slower rate than littermates, most obviously in the failure to gain weight as quickly as the other puppies.

    Hereditary Conditions

    • Puppies born with a chest bone deformity can also have trouble gaining weight and typically also have difficulty breathing and eating. This is a hereditary condition found most often in breeds that have other breathing difficulties because of their short noses and flat faces. Some breeds, such as the beagle, the border collie and the schnauzer can be susceptible to a condition in which the body fails to absorb B12; this condition usually manifests when the dogs are still young, and will result in a generally lethargy, ill appearance and failure to gain weight.

    Hyperthyroidism

    • Although rare, an adult dog can develop hyperthyroidism much like cats and humans. The dog will show signs of failing to gain weight in spite of a healthy diet and appearing to eat a normal amount of food. Hyperthyroidism can cause the dog to be extremely hungry and consume large amounts of food just to keep their weight at a consistent level; when left untreated, there will be addition symptoms like an unhealthy coat and appearance. The thyroid is responsible for functions throughout the dog's body, and a diagnosis of hyperthyroidism is usually the precursor to another underlying problem.

    Prognosis

    • The prognosis for all the causes of failing to gain weight varies not only on the condition and reason for the weight difficulties, but also on the individual dog and the speed at which the condition is noticed, diagnosed and treated. Even some genetic conditions such as failure to absorb B12 can be successfully treated with medicine. The key to continuing the long and healthy life of the dog is to get veterinary help as soon as a problem is noticed. In many cases, failure to gain weight, hyperthyroidism or the susceptibility to bacterial and viral infections can be a symptom of another underlying problem, and the prognosis will be determined by medical findings.