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Guinea pigs’ weight is an important health indicator because it indicates how healthy they are. For guinea pig owners, losing weight can be a major source of concern. There are many guinea pig owners who struggle to find an answer to the question “why is my guinea pig losing weight?” Consequently, I decided to conduct some preliminary research and consult with a veterinarian friend in order to find the answers to all of your questions.Nutritional deficiency, an unsuitable diet plan, dental problems, stress, and other health problems can all cause weight loss in guinea pigs. Weight loss in guinea pigs can be fatal if it continues for an extended period of time. Always take your pet to the veterinarian if you notice any signs of illness in them, especially if they are losing weight.There can be a variety of factors that contribute to weight loss in guinea pigs, although a small variation over several weeks is to be expected (20-50grams).Anything weighing more than 100 grams should set off your alarm. There have been numerous reports of a high mortality rate in guinea pigs after they have lost weight continuously for a period of several days.If you notice any other signs of disease or notice that your guinea pig’s weight is decreasing with each passing day, you should seek professional advice immediately.

Interested in learning more about some common diseases in guinea pigs and the symptoms associated with them? Check out our article on the subject: guinea pig diseases. What are the most common health problems in guinea pigs?


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Signs that guinea pig is underweight?

Guinea pigs are supposed to be slim; however, if they are underweight, they can become excessively thin and deformed.

They are malnourished even if you only lightly touch their bodies, which is how you can tell. Experts, on the other hand, recommend that you weigh your guinea pigs once a week to keep track of their health.

Some guinea pig owners do not weigh their guinea pigs on a regular basis, and it can be difficult for them to determine whether their guinea pig is losing weight or maintaining its current weight.

This digital kitchen scale, in particular, appeals to me. I purchased a guinea pig scale from Amazon to use with my animals. I put them in this basket and set the basket on top of the scale. I’ll weigh them later. It’s fairly simple to accomplish this in this manner, and the scale is extremely accurate.

Weighing Your Guinea Pig: What You Should Know Before You Do It!

For this reason, if you haven’t recently weighted any of your animals or have only recently brought in a new animal, you should be on the lookout for these signs to determine whether or not your guinea pig is underweight.

  • Their ribs, spine & pelvis can be felt or seen prominently.
  • The abdominal curve seems to be caved in. (Usually, guinea pigs have a smooth feel, and you won’t be able to tell the difference between their last rib and abdominal cavity.
  • The coat and skin feel rough and puffed up.
  • You will notice less dropping around the cage.
  • They squeak a lot.

Lack of energy, unwillingness to move, and excessive sleeping are all signs of being underweight, as is being overweight.

You should be concerned if you notice any of these signs, as it indicates that something is definitely wrong with your guinea pig’s health. You should seek medical attention as soon as possible.

If you weigh your guinea pigs on a regular basis, you will be able to tell quickly whether or not your guinea pig is underweight.

The weight of your guinea pig will vary depending on the breed, age, and size of your guinea pig, however. Nonetheless, here is a rough outline:

  • An adult male guinea pig weighs between 900 and 1200 grams on average, depending on the breed.
  • An adult female guinea pig weighs between 700 and 900 grams on average, depending on her size.

If your guinea pig’s weight falls below these guidelines, you can consider them to be underweight.

What causes weight loss in guinea pigs?

Many factors can contribute to guinea pigs losing weight, and each factor is unique. While it is understandable for guinea pig owners to be concerned if their guinea pig is consistently losing weight, it is critical that the problem is addressed as soon as possible.

Many people are frequently stumped as to what is causing their guinea pigs to gain or lose weight. So I decided to consult with my veterinarian and to share some of the primary factors that can cause weight loss in guinea pigs that I learned about. Here are a few examples to get you started:

  • Overgrown teeth are often a common reason. Guinea pigs have continuously growing teeth, which can occasionally grow and cause discomfort to their food pipe or gums. This usually results in a great deal of discomfort, and as a result, they are unable to properly consume their food.
  • Malnourishment from an early age It’s possible that your guinea pig never reached their maximum body weight or experienced a robust growth because of this.
  • Gastrointestinal diseases & other health problems can frequently result in abnormal growth and a shabby appearance.
  • Improper diet or poor quality hay The nutrients are frequently out of balance as a result. It is highly recommended that you provide your guinea pigs with high-quality hay and pellets.
  • Dominant guinea pigs get all the food, Consequently, they are malnourished due to the fact that the dominant guinea pigs consume most of the food and leave the remaining for the other.
  • Stress In addition, guinea pigs may experience a loss of appetite. Stress in guinea pigs can be caused by a variety of factors, including an unhealthy living environment, loud noises, the presence of other pets such as dogs and cats in the home, and so on.

Aside from all of this, there can also be some serious health issues in guinea pigs that can result in them losing weight and eventually dying.

Some of these include metabolic issues, respiratory issues, urinary tract infections, and organ failures, to name a few. You should also be on the lookout for any other signs that your guinea pigs may be suffering from a different health problem at the same time.

Also read:

We will go over some of the most common scenarios that most business owners encounter in order to better understand it.

Do guinea pigs lose weight in summer or winter?

The weight of your guinea pigs has absolutely nothing to do with the time of the year. Your guinea pig’s weight will not be affected by the weather, whether it is summer or winter.

Although your guinea pigs may appear a little larger in the winter, this is due to the fact that they grow more fur during the winter. They do this to provide additional insulation, which allows them to remain warm even when the temperature drops.

They will shed their hair once more before the summer, which will make them appear lighter in color and slightly smaller in size. It is true that the extra fur has nothing to do with the weight, but it can cause a slight increase or decrease in weight by a few grams, which is insignificant enough to be noticed.

If your guinea pig is losing weight, it could be due to a variety of other factors, none of which are related to the weather.

Get to know more about guinea pigs’ shedding, as well as what you should do to ensure their well-being during this time.

Guinea pig losing weight & drinking a lot of water

This can be an indication of diabetes in guinea pigs if they are losing weight and drinking a lot of water (in excess of what is normal for them).

The disease of diabetes in guinea pigs is common, and the loss of weight is a common symptom of the disease. Keep an eye out for other signs and symptoms such as:

A guinea pig who exhibits any of these symptoms is most likely suffering from diabetes, according to the American Diabetes Association.

Guinea pigs – Emerson Animal Health on May 1, 2018 – Emerson Animal Health

Managing diabetes can be accomplished through dietary changes and medication administration. To get a more thorough diagnosis and prescription, it is recommended that you see a veterinarian as soon as possible.

Guinea pig losing weight but eating

Unless your guinea pig is eating a special diet, it is possible that he or she is losing weight for one of the following reasons:

  • Diabetes
  • Unable to extract nutrients
  • Lack of proper balance in their diet

In the event that your guinea pig is suffering from diabetes, he or she will lose a significant amount of weight quickly. It is recommended that you keep an eye out for any other signs of diabetes and that you consult a veterinarian as soon as possible.

Guinea pigs may be infected with worms or parasites in their gut from time to time. These parasites frequently deplete the nutritional value of the food that your guinea pigs eat.

Additionally, some guinea pigs have a weak digestive system, which makes them incapable of absorbing all of the nutrients from their food. You will notice that such guinea pigs will begin to consume a large amount of their own feces in order to reabsorb the extra nutrients; however, this may not be sufficient.

A veterinarian would be able to conduct a thorough examination of the guinea pig and provide you with recommendations for further treatment.

Weight loss in guinea pigs can be caused by a variety of factors, including an unbalanced diet.

In the event that your guinea pig consumes more vegetables and less hay, their body will not gain enough calories and fiber, both of which are necessary for them to maintain their body weight.

It would be necessary to make the necessary dietary modifications and consult with a veterinarian as well.

Top-Rated Guinea Pig Supplies: Our Top Picks! Recommended Guinea Pig Supplies: Our Top Picks!

Before you read on, here are some supplies for your guinea pigs that have been hand-picked by our experts and that you should add to your wish list right away:

Guinea pig losing weight and not eating

The reduction in appetite is inversely proportional to the reduction in body weight. If your guinea pig is not properly consuming their food, he or she will eventually become underweight. A lack of appetite can be caused by a variety of factors, including:

  • Dental problems
  • Respiratory and urinary infection
  • Poor quality food

If your guinea pig is losing weight and no longer eats, you should take him to the veterinarian as soon as possible. Depending on their diet, there could be some serious health issues with your Guinea pigs’ diet.

If your guinea pigs are not getting enough vegetables in their diet, we have an ultimate guide for you that will undoubtedly be of assistance.

Please see: Why is my guinea pig not eating their vegetables? for more information.

Guinea pig losing weight and hair

Weight loss in guinea pigs that is accompanied by hair loss is usually a sign of mite infestation. If you suspect that your guinea pigs are suffering from mites, you should keep an eye out for any other signs of illness.

  • Thick skin coat followed by yellowish and crusty skin
  • Lethargy
  • Unwillingness to move
  • Hair and weight loss

If left untreated, mites in guinea pigs can cause convulsions and even death if not removed. If you notice any signs of mites, you should take your pet to the veterinarian.

Hair loss in guinea pigs can occur as a result of shedding in some cases. It has no effect on the diet or weight of your guinea pigs, on the other hand. As a result, you may need to keep an eye out for signs of other diseases.

Old guinea pig losing weight

It is quite reasonable for old guinea pigs to lose weight. Once your guinea pigs pass a certain age(5-6years), some changes start to show up. The loss of weight can be because of various reasons, including:

  • Loss of appetite that happens naturally
  • Age-related illness
  • Slower gut-processing of food, thus not eating properly.

Whatever the reason, your guinea pigs will begin to lose weight as they grow in years. It is an unavoidable fact of life, and there is little we can do to prevent it other than to ensure that they are well cared for.

So, now that we understand the various factors that contribute to guinea pig weight loss, we can devise a plan to address the problem.

How to help guinea pig gain weight?

If your guinea pig has lost weight or is underweight, there are several things you can do to help them gain weight.

To be sure, consult your veterinarian about any health issues that may be causing weight loss in guinea pigs before undertaking any weight-loss regimen.

When you are losing weight, it is possible that you are suffering from gastrointestinal parasites, dental problems, or even stress.

Once everything is clear, we can experiment with different methods to see if we can help our guinea pigs gain some weight. Follow these pointers for success.

  • Add some extra pellets to your guinea pig’s diet to give him a more balanced diet. Make sure, however, that your guinea pigs do not have a history of bladder stones, as pellets can be harmful to guinea pigs with this condition.
  • If you are currently using hay from tractor supply or other low-cost sources, switch to third-cut timothy hay. (I personally prefer small pets, so I recommend purchasing one from Amazon.)
  • Never attempt to cram an excessive number of calories into their diet at once. If you decide to increase their weight all at once, things may get even worse because their digestive system may become unbalanced as a result. Food should be introduced slowly to allow for gradual weight gain.
  • Oxbow critical care or Sherwood pet recovery formulas should be fed twice a day, according to professional recommendations. It contains some essential nutrients that can aid in the process of gaining weight as well as losing weight.
  • Fresh fruits such as apple, banana, kiwi, and other similar fruits should be included as a treat on occasion.
  • You can also incorporate some oatmeal into their diet because it aids in weight gain while also being extremely nutritious..

Feeding a guinea pig Oxbow critical care

Always keep in mind that guinea pigs have a sensitive digestive system, and introducing new food quickly or frequent changes in their diet can lead to health issues in guinea pigs.

Best food for an underweight guinea pig?

A guinea pig’s balanced diet should consist of 80 percent hay and the remaining 20 percent should be a combination of vegetables, fruits, and pellets.

If your guinea pig is underweight, you should concentrate on providing high-quality hay, a cup of fresh vegetables, and a few extra pellets to supplement his diet. I would recommend starting with 3rd cutting timothy hay from a reputable brand as a starting point.

In terms of hay, I personally prefer small pet select because they have high-quality hay and they package it in bulk, which is especially beneficial for guinea pigs that are sick or in need of weight gain.

These hays are low in fiber but extremely high in protein and fat, which are exactly what the guinea pigs require at that time of the year. Aside from that, you’ll want to make sure your guinea pigs get a cup of vegetables every day.

As opposed to a single large serving of vegetables, it is preferable to divide the vegetables into two or three smaller portions.

Increase the amount of bell peppers, lettuce, tomatoes, cilantro, and other vegetables you serve. It would be best if you could also feed your guinea pigs the 1/6th cup of pellets on a daily basis.

Make certain that you only serve high-quality pellets. Pellets that have been fortified with vitamin C would be a better option.

High-calorie foods for guinea pigs

You can feed your guinea pigs a variety of high-calorie food mixes, some of which are listed below:

Vegetables Fruits
Corn kernel Banana
Peas Grapes
Carrots Nectarines
Bell peppers Watermelon
Lettuce(Except iceberg) Apple
Cilantro Pears

Be careful not to introduce new foods too quickly, though! Also, avoid feeding food more than once or twice a week because it contains a lot of sugar, which can lead to health problems in guinea pigs such as diabetes and cancer.

I would also strongly advise you to read through these articles if you want to learn more about the guinea pig’s diet.

Sources: CARING FOR YOUR GUINEA PIG, Weight Loss in Guinea Pigs, THE DEPLETION OF VITAMIN C, Discussion with a vet, Guinea Pig Size-O-Meter