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My Dog Keeps Losing Weight, What's Wrong?

My Dog Keeps Losing Weight-What's Wrong?

If your dog keeps losing weight, it's quite normal to be concerned. When a dog starts losing weight it's suggestive that the dog's metabolic use of nutrients falls short of his energy intake. Weight loss, especially of the unexplained type, can be indicative of disease and should prompt veterinary evaluation. Generally, weight loss in dogs is first noticed by dog owners who become aware of changes in their dog's body conformation. The dog's ribs may be become more prominent or dog owners may notice a reduction in pounds when taking their dog's weight. The decrease in body weight (generally a 10 percent or more weight loss) is therefore based on several factors such as measurements, owner perception, and reliance on standardized weight charts. Following are several reasons why your dog keeps losing weight.

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My Dog Keeps Losing Weight Despite Excess Hunger

A dog losing weight despite having a ravenous appetite of course is concerning because things do not add up. Where is all the food going?

When dogs lose weight despite eating well, one should worry about several conditions that cause loss of nutrients or perhaps the nutrients are not being properly assimilated as they should.

Conditions to blame may include hypermetabolic conditions (conditions that cause an increased rate of metabolic activity) as seen during pregnancy or lactation or in medical conditions such as heart failure, fever, chronic infections and cancer.

In several of these medical conditions, the dog's metabolism increases and utilizes nutrients to combat disease.

Presence of parasites in the digestive tract may also be a culprit considering that parasites "steal" nutrients and may cause a dog to always feel hungry.

Did you know? Dogs suffering from arthritisand not moving around much may suffer from loss of muscle mass due to disuse and therefore some level of weight loss is expected. If your dog is suffering from degenerative joint disease, consult with your vet.


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My Dog Keeps Losing Weight and Not Eating

In the case of a dog losing weight but not eating, it makes more sense for the weight loss to happen considering the decrease in nutrient intake. There are several conditions that may cause a dog to lose his appetite. The anorexia may be triggered by infectious or inflammatory diseases, neurological disorders, exposure to toxins, organ failure, digestive disorders (see below) or metabolic abnormalities. Unfortunately, often cancer is a cause of weight loss in dogs. 

Dogs with a loss of appetite and weight loss may be suffering from dental disease which makes chewing painful and leads to weight loss due to the negative association between chewing and the painful experience.

A dog's environment should also be evaluated when dealing with weight loss considering that stressful events may cause a dog lose appetite and not eat.

Dog Losing Weight With Digestive Problems

Digestive problems are often a common cause for a dog to lose his appetite and weight. The dog may be eating properly but losing weight because the food is not being absorbed or the dog may be losing weight because he has lost his appetite and is not eating.

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Nausea, regurgitation, vomiting and diarrhea can cause rapid weight loss as the dog suffers from nutrient loss, especially when the underlying conditions aren't addressed in a timely matter.

Vomiting and diarrhea are often self-limiting, meaning that they tend to last a short period of time. Once the dog's body gets rid of the offensive food or other item ingested, the body should recover with a brief fasting followed by a bland diet and. However, repeated vomiting and diarrhea is often a sign that there's an underlying problem that is not being addressed such as an intestinal blockage where an object is mechanically blocking the passage of food.

When a dog is suffering from repeated regurgitation, vomiting and diarrhea, it's therefore important to seek veterinary assistance in order to find the underlying cause.

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Dog Losing Weight and Fever

 My dog keeps losing weight, what's wrong?

My dog keeps losing weight, what's wrong?

When a dog is losing weight, getting the dog's temperature may help the veterinarian determine what may be going on. A dog's normal temperature is 101 to 102.5 degrees Fahrenheit. When a low-grade fever or high fever is found in a dog who is losing weight, it's important to determine what may be causing these symptoms.

Dogs suffering from weight loss and fever may therefore be affected by bacterial or viral infections, inflammatory conditions (such as a bout pancreatitis), immune disorders, exposure to toxins, and certain types of cancer (lymphoma). As with other types of weight loss, a dog losing weight with a fever requires veterinary evaluation to help sort out the underlying cause.

The lowered absorption of nutrients in a dog with a fever may be caused by the impact on metabolism caused by the fever and underlying condition itself (increased energy demands) or its associated loss of appetite or both.

Dog Losing Weight from Malnutrition

In some cases, the dog loses weight not because of a specific underlying medical condition, but because he is not receiving the correct amount of calories. This may not be much common nowadays with dogs fed commercial diets, since feed regulations are enforced by state and federal regulatory officials, but problems may still occur if dogs aren't fed an appropriate diet or in the correct quantities.

If you are bringing your dog to the vet for weight loss, it's therefore important informing the vet about what the food you are feeding, the exact amounts fed and frequency of feeding. It's also important to provide information about any supplements or medications your dog is taking.

There may be chances you may be feeding a low calorie diet or a diet that is poor quality or perhaps you may be underestimating your dog's energy needs. If you purchase dog food in bulk, there may be chances that it has spoiled and not providing adequate amounts of nutrients.

Did you know? Dogs kept outdoors in the cold months of the year require extra calories and therefore dietary adjustments. Consult with your vet for dietary recommendations.


"An adult dog which is losing weight for no obvious reason and is not eating is always a cause for concern and this actually is quite a common scenario in a vet's consulting room. While occasionally it can be something simple and so easily corrected there is always the possibility it might be something more serious."~Dr. Scott Nimmo

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