Why Is My Chinchilla Losing Weight?

Your chinchilla’s weight is vital for its health. Too thin or too heavy, and your chinchilla could get sick, or even die. So, if your chinchilla is losing weight, you have to figure out why as soon as possible.

New owner, don't know where to start? Or do you need a handy chinchilla reference guide? Check out our Chinchilla Care 101 eBook, or get what you need from our online store!

Your chinchilla’s weight is vital for its health. Too thin or too heavy, and your chinchilla could get sick, or even die. So, if your chinchilla is losing weight, you have to figure out why as soon as possible.

Why is my chinchilla losing weight? Your pet could have a health issue which stops it eating, or stops it absorbing the nutritional value of its food. Or, there could be an issue with your chinchilla’s food, e.g. it’s the wrong kind or there’s not enough. Monitor your chinchilla’s weight, correct the problem, and take your pet to the vet. 

Consistent weight loss over time is a severe negative sign for your chinchilla’s health. As such, you should take immediate action if you notice your chinchilla losing weight. To learn how to spot this problem, and what to do, read the guide below.

Why Is My Chinchilla Losing Weight?

Chinchillas have dense fur, so weight loss can be difficult to detect.

Chinchillas lose weight when they don’t get enough energy from their food, compared to the energy they need to expend. They begin to use up stores of fat, and later on, muscle.

There are many reasons why a chinchilla loses weight. They are related either to:

  • A health issue with the chinchilla which stops it from eating, or stops it from absorbing the energy in its food
  • An issue with your pet’s food, e.g. the wrong kind of food or the wrong amount of food

You must identify the issue and correct it. Otherwise, your chinchilla will use up all of its energy reserves. If left in such a state, it could potentially starve.

The most common reason why a chinchilla loses weight is that it has an issue with its teeth.

When your pet’s teeth have grown crooked, cause it pain, or have fallen out, it can’t eat properly. With your pet hardly eating it can lose weight quickly.

But as you’ll see, that’s far from the only reason your chinchilla might lose weight.

Key Issue: Chinchilla Won’t Eat/Not Eating Enough

It stands to reason that if a chinchilla doesn’t eat enough food, it will begin to lose weight. There are several reasons why a chinchilla might stop eating. If you spot that your chinchilla is getting thinner, then it’s likely one of these issues which is the cause. They include:

  • If the chinchilla is sick. When a pet is sick, it can go off its food. 
  • Your chinchilla has issues with its teeth. When your pet’s teeth hurt, it doesn’t feel able to eat food.
  • If you aren’t giving your pet the right food. You may be feeding a species-inappropriate food, or a food that doesn’t have enough energy in it.
  • One chinchilla is eating the other chinchilla’s food. Sometimes because of dominance issues, one chinchilla can hog the food and not allow the other to have enough. Over time, the subordinate chinchilla can lose weight.

To figure out what’s wrong with your pet, observe it for a while. As you observe it, you may see that it’s in pain or sick; or, you might spot that its cage-mate is taking all of its food. You can then correct the problem once you spot it.

Why Do Dental Issues Cause Weight Loss in Chinchillas?

chinchilla food pouches

Dental issues are the leading cause of weight loss not just in chinchillas, but in all rodents. That’s because of the role that a rodent’s teeth play in its diet and its life.

While teeth are important to all animals which have them, this is especially the case for rodents. These animals each have four large incisors at the front of their mouths.

While without one tooth, a person can continue to eat, without one of their incisors a chinchilla will struggle.

That’s because these incisors are essential to breaking into nuts and seeds, and to cutting dry hay into manageable, edible chunks. If your chinchilla can’t do this, or at least can’t do this as quickly or easily, it will gradually lose weight.

While these teeth are durable, they can crack, break or fall out. Chinchillas and other rodents can regrow these incisors, so the loss of one isn’t a death sentence. But it may make your pet lose weight.

Why Do Chinchillas Lose Weight When Sick?

Sickness affects a chinchilla’s diet in two ways. First, it discourages the chinchilla from eating. But the enhanced immune response necessary to fight off infections/other issues requires extra energy.

This means that a) chinchillas which stop eating when sick lose out on energy from food, and b) being sick requires even more energy than usual. These two factors combine to mean that a chinchilla rapidly loses weight when ill.

Some health problems can specifically affect the mouth, teeth and throat. These issues make it so that the chinchilla physically can’t eat because it’s in pain, the same as above with regards to its teeth.

Chinchillas can also experience diarrhea. Like in other animals, this is where the chinchilla’s stool is loose and runny. Often, diarrhea occurs when food is only partly digested. When this is the case, it means that the chinchilla isn’t absorbing all the nutrients it needs from its food. This makes it lose weight if it experiences repeated diarrhea.

Chinchilla Eating But Losing Weight

What may be even more worrying is if your chinchilla is eating normally, but is still losing weight. This is especially concerning because it means that even if you feed your pet more, it may still continue to lose weight.

Wrong Kind of Chinchilla Food

You may be feeding your chinchilla the wrong food mix. People can mistakenly feed their chinchillas food mixes intended for other rodents, for example. Or, they can pick low-quality ones which are packed with just one cheap ingredient, and lack a rounded, balanced supply of nutrients.

You should feed your chinchilla hay, such as timothy hay or orchard grass hay. Somewhere around 80-90% of your pet’s diet should be nothing but hay. This gives your chinchilla the right amount of fiber in its diet, which is essential for its digestive system.

If you were to feed your pet the wrong kind of food, it may experience weight loss or weight gain. Weight gain is more common because pellet mixes intended for other rodents can contain lots of seeds and nuts, which are too high in fat for your chinchilla’s general diet.

How Do Parasites Make Chinchillas Lose Weight?

Chinchillas can lose weight because of parasites. Like other animals, chinchillas can have internal parasites like roundworms. When parasites live in an animal’s gut, they feed on the food that it eats. This means that the animal gets less energy from its food, and can miss out on micronutrients.

Chinchillas can also get tapeworms. Tapeworms are worse than roundworms because they’re much bigger. They absorb even more of the nutrients your chinchilla is trying to digest.

If you think your chinchilla may have parasites, be careful. Roundworms can be transmitted to other pets, and even to humans. So, begin appropriate treatment as soon as possible. Wash your hands every time you handle your pet.

Talk to a vet if you need further advice.

Chinchilla Kit Losing Weight

A chinchilla baby (better termed a ‘kit’) can lose weight even when it feeds on its mother’s milk. This can happen because:

  • The other chinchilla kits are bigger and stronger, and make it difficult for the kit to get milk
  • The mother rejects the kit because there is not enough milk to go around

This is a reasonably common occurrence in animals which have larger litters. While chinchillas have smaller litters of between two and six babies, this does still happen.

When this occurs, you can try hand feeding the kit. This is a difficult task, no matter what kind of pet you have. You must feed the kit every 1-2 hours, because they need regular meals. And that doesn’t just mean daytime: it means around the clock.

You may also need to stimulate its gut with gentle rubs, and by rubbing its back/front with warm, damp cotton wool balls. This encourages it to digest. Throughout this time, weigh your chinchilla kit and compare it to the others which are feeding from their mother.

Even with this help, the chinchilla kit may still pass away. So, be prepared for this eventuality. Don’t assume that it will survive.

Chinchilla Losing Weight and Fur

Chinchillas will lose fur because of an issue called ‘fur slip’. This is the term for when a patch of your chinchilla’s fur falls out after handling. Stress and anxiety can make the issue worse, or make it more likely to happen.

This occurs because of the physiological reaction to stress, but also because of over-barbering, where a chinchilla chews its own fur or the fur of a cage-mate too frequently or too hard. This causes bald patches. As such, your chinchilla could be losing weight and fur at the same time because of stress.

If your chinchilla is both losing weight and fur, take it to the vet as soon as possible. They can further advise you as to your pet’s condition.

Need to Know FAQs

It’s good to know what might cause a chinchilla to lose weight. But knowing that is useless unless you know what a healthy chinchilla weight is, and how to correct the situation. Here’s everything else you need to know.

How Much Does a Chinchilla Weigh?

The average weight of a chinchilla varies depending on the sex, subspecies, age and genetically-determined size of your chinchilla. As such, there is no one answer. So, when is a chinchilla too skinny? Anything more than 550g/19.5 oz is a healthy weight.

Some owners say 450g+. The reason that there’s disagreement is that a chinchilla’s genes largely determine whether it is smaller or larger than usual, so there’s lots of variation.

What’s more important is that your chinchilla isn’t consistently losing weight. A small amount of weight loss and weight gain from week to week is no issue. But if your chinchilla is losing weight over time, that’s bad.

How to Weigh a Chinchilla

Take your kitchen scales and place them on a flat surface. Place your chinchilla in the bowl that comes with the scales. If you don’t have one, use a regular bowl.

With everything set up, there are two ways to gauge the weight of your chinchilla. Modern scales usually have a function which allows you to reset the readout to zero. The point is so that you can put a bowl on the scale, cancel out the weight, then take the weight of whatever you put in the bowl. If your scales have this function, do this before putting your chinchilla in the bowl.

If your scales can’t do this, don’t worry. Weigh the bowl on its own and make a note of the weight. Then, put your chinchilla on the scale inside the bowl. Take the first measurement away from the second one.

You don’t need any special kit to weigh your chinchilla. If you have a set of kitchen scales, you can use these. Ideally, you should use scales which have show the weight in grams. Grams are a metric measurement, but they’re small units so are more accurate than ounces. Plus, it’s common practise to weigh pets in grams, so you can compare more easily.

Chinchilla Food for Gaining Weight

If you want a chinchilla to gain weight, you should feed it food with a higher fat or protein content. Fat and protein contain more calories per unit of weight than carbohydrates/sugar. Therefore, your chinchilla can eat small amounts of high-fat or high-protein food to gain its weight back.

High quality food mixes may have small amounts of these foods in them already. But if you’re especially concerned, you can add in a small proportion of high-fat seeds. Unsalted sunflower seeds are a good choice, but don’t add too many, or your pet won’t eat the rest of its food.

Bear in mind that you don’t want your chinchilla to gain lots of weight at once. This would cause just as much trouble as it solves. You want your chinchilla to gradually gain its weight back over the course of weeks.

If your chinchilla is still losing weight even once you fix its diet, talk to a veterinarian. The vet can:

  • Recommend other foods that help a chinchilla gain weight
  • Identify any health issues that may make your chinchilla lose weight, and help to fix them
  • In the worst cases, put your pet to sleep (e.g. if it’s too sick to recover)

Remember: while you can take steps to help your pet, and learn lots of useful things about their health, there is no substitute for the advice and care of a vet.

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New owner, don't know where to start? Or do you need a handy chinchilla reference guide? Check out our Chinchilla Care 101 eBook, or get what you need from our online store!