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Can Guinea Pigs Chew on Cardboard?

Ruminating the Cavy Colon 

Nothing is as satisfying as realizing and accepting who you really are… deep down. That’s when a person can finally just relax and be at peace. We can learn a lot about just being by observing our guinea pigs. They know exactly who they are and what they need. They’re grazers, and when they’re left to do just that, they’re happy, healthy, and their lives are bliss.

The guinea pig digestive system is built for grazing. It can handle pulpy fiber, which it processes through the cecum. Cardboard is a pulpy fiber, so can guinea pigs chew on cardboard? Technically your piggy’s system can handle it. But be careful, large pieces could cause a choking hazard or intestinal blockage. Cavies naturally graze on grass, and leafy plants. Timothy Hay is the generally accepted substitute, and your piggy should be provided with an unlimited supply to aid in overall digestion and manage tooth length.  

Hay, It’s Not Cheap

When I adopted my first two piggies, Thelma and Louise, I marched right into the local pet store and purchased four bags of Timothy Hay. I was determined to ensure my little guys would never meet a hungry moment. 

However, I was quickly dismayed when they hoovered through the 48oz packages, for which I had paid $9.99 each, in less than two weeks! 

I feared my furry friends would quickly eat me out of house and home!

Amid my first cavy catastrophe, I scoured the internet in search of an economical solution. 

I knew their consumption of hay and grass was crucial for digestion, but my children needed to eat too! 

I considered shredding some cardboard boxes I had in the garage to defray the cost of my cavies special diet. But luckily for me, a friend of mine with horses suggested that I visit the local saddlery. To my delight, they sold me an entire bale of Timothy Hay for only $35.00.

I happily hefted my score into my minivan and headed to the hardware store. There, I picked up a rubber fifty-gallon trash can and lid for only $25. The can was only able to hold a little more than half of the bale, and I gave the rest to my friend who’d offered such a brilliant solution. 

My mind was at ease, and my financial woes were relieved. I had saved a bunch of cash, and my cavies were sure to have an unlimited supply of hay to assist them with healthy digestion.

Piggy Digestion

Guinea pigs, like most herbivore mammals, have a large (for their size) active cecum, which is attached to the colon. 

This sac breaks down bacteria and allows the digestion of cellulose. 

Cellulose is a major component in the chemical make-up of green plants and grass, the primary component of the cavy diet.

Cardboard is made from a cellulose pulp derived from wood and grass. 

So, while I prefer to keep my piggy away from processed foods, cardboard isn’t dangerous to their overall digestion, but it’s really just junk food. And remember, guinea pigs can overeat.

So keep in mind that natural vitamins and minerals are important parts of your guinea pig’s diet. 

A major consideration to be aware of is that they cannot store vitamin C, and even natural grass and plants don’t provide the amount your piggy needs to stay healthy.


As natural grazers, guinea pigs are genetically accustomed to spending their days munching on low-calorie plants and grasses. 

Cavy teeth are designed for lots of masticating. They have an open root, which means they never stop growing and are kept short by grinding them down when they chew on high cellulose foods. 

This activity manages both their digestive systems and dental health. 

While cardboard is an option, and Timothy Hay definitely meets the overall dietary need, I believe nothing is better than allowing your piggy to graze on a good old herbicide-free lawn occasionally. I typically lay weed killer and fertilizer on my lawn once every two months. 

After about three days, it should be safe for your piggy to do a little grazing. 

Personally, I keep one of the small, blue, hard plastic kiddie pools that I’ve cut the bottom out of behind the shed in my yard. 

I regularly take this nifty, “escape-proof” gadget out to the back lawn and put my piggies in for an old fashioned grazing party. Their immediate popcorning quickly lets me know that they appreciate the treat every time.


Our piggies have sensitive little systems they learned to manage through thousands of years of evolution. But they’re domesticated now, and proper care requires a bit of education and creativity. Luckily, there are countless sources out there dedicated to providing accurate and helpful information to our furry friends. Our little cavies bring a lot of joy into our lives, let’s keep them healthy and happy.


Digestive System https://www.ncbi.nlm.nih.gov/pubmed/7149278

Timothy Hay https://squidgypigs.com/2018/01/24/timothy-hay-vs-meadow-hay/

Cavy Teeth https://www.pbspettravel.co.uk/blog/guide-guinea-pig-teeth/