Weight loss

By nature, guinea pigs should be on the ‘plump’ side but should not be overweight as this can cause health problems. However, unexplained weight loss can be a serious clinical sign that something is wrong with your guinea pig.

The obvious and first question (which is sometimes overlooked), is does the guinea pig have enough food to eat? Has their food been changed recently or a new bag opened that may taste slightly different? Has the company changed the ingredients in the food at all? Is the food still within the Best Before date? Guinea pigs can be very picky with anything that tastes slightly different to what they are used to, so it is best to rule these things out quickly.

Have you recently introduced another guinea pig who may be eating more of the food? Is the companion guinea pig getting larger? This may indicate that the other guinea pig is eating more than their fair share of the food and possibly bullying the other guinea pig, so they are unable to get to the food.

It is important to have ruled out these obvious causes prior to your veterinarian commencing any diagnostic tests. If none of the above apply then a medical reason is likely to be causing the weight loss.

Weight loss can be caused by a vast array of reasons, but dental disease is by far the most common cause of weight loss in guinea pigs. Any guinea pig who finds it painful to eat is unlikely to eat enough food to take in enough calories and will therefore begin to lose weight. The molar teeth can overgrow and ‘bridge’ over the tongue, making it impossible for the guinea pig to chew and eat. There may be no other signs of dental disease other than weight loss, but the guinea pig may show excessive salivation, attempt to pick up and eat foods, but then leave them or have a foul smell come from their mouth.

Tumors and cancer take away vital nutrients leading to weight loss and renal, liver and heart disease can all cause weight loss too.

Guinea pigs that have mites may be so itchy that they spend a vast amount of time and energy itching and scratching, leading to weight loss. If you notice any signs of mites, including bald patches, scaly skin, flaky skin, sores or wounds, then you need to contact your veterinarian to determine which mite is responsible and receive the correct treatment.

Firstly it is important to rule out common causes. A thorough dental examination, which should include a clinical examination and x-rays to assess the tooth roots is vital. This needs to be done under sedation or general anesthesia, and if the guinea pig is not physically well enough to undergo a sedation/GA then supportive treatment by the way of syringe feeding, fluid therapy, pain relief and prokinetic medication to support the gastrointestinal tract should be implemented first to stabilize the guinea pig, which helps to make the anesthetic safer.

Blood work may be needed to assess the guinea pigs renal and liver parameters and may also have to be performed under sedation.

Diagnostic imaging such as x-rays, CT scan or MRI scan may be required if a tumor is suspected.

Your veterinarian will be able to decide what tests, and in what order they should be run, after clinically assessing your guinea pig.

If your guinea pig is insured then they should be covered for the costs, but it is a wise idea to check with your insurance company first.

Your veterinarian will select the most appropriate treatment depending upon the cause of the weight loss. It is important to remember that weight loss itself is a symptom of a disease process and not a disease in itself and the underlying cause needs diagnosing and treating regardless of what this is found to be. Some causes of weight loss are easier to treat and manage than others. For example, mild dental disease can be managed with alterations to the diet and regular dental treatments but can often not be cured.

Tumors, depending upon the location and type of tumor, may be surgically removable. Renal, heart and liver disease may be managed with medications, again depending upon the cause and severity, and how well the guinea pig tolerates treatment.

Whilst your veterinarian is diagnosing the cause of the weight loss, the guinea pig should be offered syringe feeding and fluid therapy to try and increase their calorie and fluid intake. Other medications may be prescribed by your veterinarian who will be in the best position to know what is best for your guinea pig.

Some older guinea pigs may struggle, especially during the colder months of the year, to keep adequate weight on them. Increasing the calories in the diet by increasing the pellet ration should help with this problem. You could also consider bringing them into a warmer environment, such as the house or an unused garage/shed. This will help them to stay warm without using as many calories to do so and always ensure they have at least one guinea pig companion to snuggle up to, to help them keep warm.