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Can Guinea Pigs Eat Onions: Why This Vegetable Is Off-Limits to Your Cavy

Can Guinea Pigs Eat Onions

Guinea pigs require fresh produce to source valuable vitamins, trace minerals, and nutrients as part of a complete and balanced daily diet.

There are many wonderful vegetables and fruits you can offer to your guinea pig that will help round out the nutrition your pet gets from their regular diet of hay and grasses.

It is only natural to wonder if onion, which is a very popular vegetable that people love to eat, is also safe to offer to your cavy. After all, your guinea pig eats lots of vegetables that people also eat, so why not onion as well?

Unfortunately, onion is not safe or healthy for guinea pigs to eat. Read on to learn what makes onion toxic to guinea pigs.

Can Guinea Pigs Eat Onions

Guinea pigs, like all pets, cannot eat onions. As the RSPCA points out, both onions and onion grass are on the list of foods that you should never feed to your guinea pig.

In the following sections of this article, we will talk about why onions are not safe to feed to your guinea pig.

Learn About Unsafe Foods for Guinea Pigs

In this informative YouTube video, you can learn about what types of products and grasses are not safe to feed to your guinea pigs.

You will also learn about some surprising sources of toxins that may affect whether fresh foods are safe to feed to your guinea pig.

What Makes Onion Toxic to Guinea Pigs

As VCA Animal Hospital explains, onions come from the Allium family of plants.

All the plants in the Allium family are toxic to dogs, cats, and other companion animals, including guinea pigs.

The reason that this plant family is so toxic is because of certain naturally occurring chemical compounds called disulfides and thiosulphates.

As Pet Insurance explains, disulfides and thiosulphates can cause rupture of the red blood cells. When this happens, it is called hemolytic anemia.

What Are the Symptoms of Hemolytic Anemia in Guinea Pigs

While you can definitely control whether your guinea pig has access to onions inside your home, you may not be so lucky when your guinea pig is foraging around outside.

You may not even know if there are wild onion bulbs that are dormant in your yard or garden, left there by a previous owner or tenant.

This is why you need to learn the warning signs of hemolytic anemia so you can seek out urgent veterinary care if you see any symptoms in your guinea pig.

The main symptoms of hemolytic anemia are:

  • Rapid breathing.
  • Yellow or pale gums.
  • Rapid heart rate.
  • Trouble catching their breath.
  • Lethargy.
  • Abdominal pain.
  • Urine discoloration.
  • Vomiting.
  • Diarrhea.

Because guinea pigs are quite small, the symptoms might manifest more quickly depending on how much your pet ate. However, it can take some time for symptoms to develop if your cavy only ate a small amount of onion.

Other No-No Vegetables In the Onion Family That Your Guinea Pig Can’t Eat

As the popular Guinea Pig Forum for owners points out, onion is not the only vegetable that is on the no-no list for feeding to your guinea pig.

Onions are one of several vegetables or bulb plants in the Allium family. All plants in this family are toxic. The other most popular members include leeks, chives, and garlic.

However, there are more than 95 known and documented species in the Allium family. They all have two things in common: they are very strong in scent and flavor and they are all bulbs, which means they stay dormant underground for part of the year.

All varietals of leeks, chives, onion, and garlic – including ornamental (not to eat) varietals – are off-limits to your guinea pig. All can cause harm to the red blood cells and induce hemolytic anemia.

What Do Allium Plants Do to Your Guinea Pig

As VCA Animal Hospital goes on to explain, when your guinea pig ingests onion and the toxic compounds disulfides and thiosulphates, this starts an internal chain reaction.

Red blood cells are the oxygen couriers of your guinea pig’s body. The chemical compounds in onion cause the outer membrane of your guinea pig’s red blood cells to become oxidized, or increasingly thin and fragile.

When the membranes become thin enough, they burst open. This causes internal bleeding and deprives cells and organs elsewhere in the body of the oxygen they need to function. Clotting function, heart function, and breathing are also affected.

How Is Hemolytic Anemia Diagnosed in Guinea Pigs

There are lots of health conditions that might cause symptoms that are similar to hemolytic anemia in guinea pigs.

The important fact to remember here is not to wait. Guinea pigs, like most companion animals, will try to hide when they feel unwell or weak as part of their survival instinct. So by the time you see severe symptoms, it may be too late.

Your veterinarian will rely on your observations to start looking for the cause of the symptoms. This is why it is so important to never leave your guinea pig unsupervised in the yard or with a pet sitter who doesn’t understand how to feed guinea pigs!

The veterinarian will look for certain symptoms and can also do a blood test to detect Heinz bodies, which are small changes to the red blood cell membranes that indicate fragility.

Hidden Dangers of Onions to Guinea Pigs

Guinea pigs are smart and sociable and may learn to beg for foods you are eating that they want to try.

It is important to remember that most “people” foods are simply not safe for guinea pigs. It is quite common to add onions and other allium bulb vegetables as flavorings to processed foods in liquid, whole or powdered form.

Allium vegetables may also be present in health supplements, baby foods, sauces, soups, salad dressings, vegetable marinades, and more.

Because of this, the best rule to follow is to never mix your own food and your guinea pig’s food. Keep a portion of fresh produce cavy treats separated out in your refrigerator to make sure your guinea pig never encounters allium toxins in any form.

Treating Onion Poisoning in Guinea Pigs

It can be so upsetting to learn that your guinea pig has eaten onion and may be suffering from toxicity or poisoning.

The earlier you get treatment, the more positive your pet’s prognosis is likely to be.

Your veterinarian will treat your cavy based on the severity of symptoms. It may be necessary to induce vomiting to clear out the stomach of any remaining onion.

For serious anemia, your guinea pig may need intravenous fluids, oxygen therapy, and even an infusion to replace lost red blood cells.

It is important to know that even very small portions of onion can cause serious anemia for a small pocket pet like a guinea pig. And since symptoms can be delayed, it is vital not to delay seeking treatment at the very first sign that something is amiss.

How Much Onion Is Too Much For Guinea Pigs

If your guinea pig nibbled just a little bit of onion in the backyard, should you take your pet to the urgent care now?

There are no statistics on how much onion is too much for cavies. Just in case, it is smart to call your veterinarian.