Reasons Why Your Guinea Pig is Not Eating and What to Do

Updated: June 7, 2023

Whether your guinea pig is very young and has never eaten fortified food before, or if your adult guinea pig is suddenly refusing their fortified food, ensuring that your pet eats their daily allotment of pellets is vital. Fortified food contains many vitamins and minerals not found in your guinea pig’s hay, greens, or treats, making them essential to your pet’s daily nutritional requirements.

Why Your Guinea Pig Isn’t Eating: Starting With The Basics

While there could be many reasons for your guinea pig to refuse their uniform food related to normal changes in appetite and personal taste preferences, consider the following to start troubleshooting:

Are you offering a uniform, nutritionally-complete fortified food, or a muesli mix?

If your pet is eating a muesli mix or a type of food that is not species or age-appropriate, we highly recommend changing their food by slowly transitioning diets. You can learn more about the importance of species and age-appropriate foods through our All About Fortified Foods information sheet!

Have you recently changed your pet’s fortified food?

Sudden changes to your pet’s diet can sometimes lead to refusal, which can result in serious gastrointestinal issues. Small animals are prey species and may naturally refuse food if they detect changes that seem suspect. Refusal can be compounded if your pet has always been a particularly picky eater. Refusal can commonly occur during the following situations:

• When a pet parent offers a different brand than what the pet is used to
• When the pet parent offers a different product line within a brand
• In some cases, when pet parents shift from an old bag of food to a new bag of food within the same product line

If you intend to transition your guinea pig’s food from one brand to another, it’s essential to understand the pros and cons of doing so to ensure your small friend doesn’t suffer from any GI upset or simply refuses to eat.

Is your pet behaving and eating normally otherwise?

If your pet is acting lethargic, is not urinating or producing normal fecal matter, or is refusing hay, treats, and greens in addition to refusing fortified food, it is pertinent that your pet is seen by an exotics veterinarian immediately. As prey species, small animals adapted to mask any sickness they might have, so as to not be an easy target for predators. This instinct remains even though your pet lives in the comfort of your home, which means they often will not appear ill until they are so sick that they can no longer mask their illness. The symptoms listed above may point to your small pet being very ill, and not receiving treatment for these symptoms could prove to be fatal.

How To Rewire Your Guinea Pig’s Brain

Changing your guinea pig’s eating habits can take time and patience. The following tips can help speed up the process of teaching your pet to more readily accept their food.

• Remove your pet’s food bowl for a short amount of time
• Offer a few pellets in place of a treat
• Show excitement when offering your guinea pig his food

Remove your guinea pig’s food bowl for a short amount of time.

Offer the bowl and pellets to your little one a few hours after taking it out to see if their interest in the food has changed. If the fortified food has not been replaced in the past day, try disposing of the old pellets and offer food fresh from the packaging. The hay aroma from the newly-replaced pellets may entice your little one. It may also help to change where you are placing the pellet bowl within the habitat. For example, if you are placing the bowl far away from your pet’s hiding spot, place it closer to their hide, since this is where small pets tend to feel safest. Treating fortified food like it’s a hot commodity, rather than as part of the unmoving scenery of your pet’s habitat, might help them come to think differently about their pellets.

Offer a few pellets to your pet in place of a treat.

Measure out your pet’s fortified food beforehand and take 5-6 pellets from this allotment. Hand-feed the pellets to your pet while interacting with them, such as during couch time or while teaching them a new trick. Acting like your pet’s pellets are a reward can help to rewire your small pet to think their pellets are a treat, helping ensure later on that they eat their uniform fortified food every day.

Use your “excited voice” when giving your pet fortified food.

If you already use a higher-pitched tone of voice while praising your small pet, using that same voice can be an effective method to help get your pet excited about their food. As many pet parents know, small herbivores can heavily rely on audio cues to help predict when food is on the way (think of how some guinea pigs lose their minds when the fridge opens!). Some pet parents have developed a phrase that their pets recognize to mean “food time” (one of our own employees’ guinea pigs recognize the phrase, “Is it time for piggy dinner?”). Since small animals quickly learn that bag crinkling, fridge doors opening, or a change in their pet parent’s voice can signal that food will arrive soon, this behavior can be used in such a way to help change your small pet’s perception about how exciting uniform pellet food can be.

Other Options To Help Your Pet Eat

Working to restructure how your guinea pig perceives their uniform fortified food can help keep your pet from refusing their food long after they’ve gone through the re-learning process. However, reconditioning small animals does not happen overnight. It will likely take time, and that is time that your pet may still have a tepid-at-best interest in their fortified food. While you are working to alter the long-term behavior of your pet, here are a few methods that might help in combination with the methods above:

• Dilute a bit of organic apple juice with drinking water and use a spray bottle to lightly spritz the dilute solution onto a daily allotment of your pet’s pellets. The pellets should be thinly spread on a clean plate or cookie sheet first. After you have sprayed the pellets once or twice with the solution, allow the pellets to dry, then serve them to your pet. The small amount of solution can help bring out the hay aroma of your guinea pig’s fortified food, and can also add a bit of sweetness to the pellets. It’s very important to not give your pet any non-diluted apple juice, as the high amount of sugar can upset their stomach. We recommend a dilute solution of 1 part apple juice, 3 parts drinking water. After 8 hours, dispose of the spritzed pellets. If you decide to keep the solution in the spray bottle rather than mixing a new solution each time, store the solution in the refrigerator. Make sure to avoid juices that have added sugars, as these are not healthy options for your pet.
• Sprinkle a small amount of dry Critical Care Herbivore onto the pellets, mixing the powder throughout the bowl. Offering uniform food in this way can make the pellets more interesting to your guinea pig, especially if they already love the different flavor offerings of Critical Care. Critical Care Herbivore is currently offered in Anise, Apple-Banana, and Papaya flavors.
• If your guinea pig is eating their greens, you can try mixing the greens with pellets in order to make a small salad! We recommend that pet parents shred the greens into smaller pieces first, making it easier to mix the pellets in. Unless a vet recommends it, do not withhold greens in hopes that they will eat their fortified food instead. Greens are an essential part of your pet’s daily diet and help keep your little one hydrated.

It’s important to remember that if you use any of the three methods mentioned above, you need to slowly transition your pet away from the method you chose. Suddenly ending these methods of presenting pellets might cause your pet to go back to refusing their fortified food, meaning you’ll have to start the process over.

If the methods above are attempted and fail to help, it’s worth exploring the possibility of offering a different line of pellets to your little one. Since some pets are especially discerning individuals, Oxbow has two fortified food lines for young guinea pigs, and three pellet lines for adult guinea pigs. All of Oxbow’s food is nutritionally complete, and one line is not necessarily “better” than another. The different lines are simply available to both provide pet parents with options that align with their personal values, as well as to provide different flavor profiles that appeal to small animals’ individual taste preferences. Here’s A Side-By-Side Look at Oxbow Fortified Foods.

Other Notes and Considerations

Guinea pigs are highly scheduled animals. Offering pellets at the same time every day may help your pet anticipate when food will be provided, and by extension might help them become more interested in pellets over time. You might even find that your guinea pig will get very excited (or become very demanding) at the approximate time of day that you feed them pellets!

If your guinea pig is under 6 months old, offering alfalfa hay (if it is not present already) can help ensure that your young pet is receiving some of the nutrients their growing body needs. Alfalfa hay is legume hay and therefore high in calcium, so while you accustom your little one to fortified food, mixing alfalfa hay into their grass hay can help fill in a couple of nutritional gaps. Alfalfa hay tastes sweet, so pet parents may find that their young pet takes to it quickly! Keep in mind, alfalfa hay should only be offered to adult herbivores as an occasional treat and should not be a regular part of their diet due to its high calcium content.

If you have tried many of these methods and your pet is still not interested in their uniform food, schedule an appointment with your qualified exotics veterinarian. Your pet might be refusing their food for a reason that is not easily seen without the aid of a professional’s eye. Your veterinarian may also provide additional resources and advice to make sure your guinea pig is getting enough vitamins and minerals to stay happy and healthy.