Ask the Experts: The Risks of Spoiled Vegetables for Guinea Pigs

Getting diet right plays a huge role in ensuring the health and happiness of our guinea pigs. One common concern among piggy parents revolves around the variation and quality of vegetables in their pigs’ diet – specifically, the risks associated with spoiled vegetables. This topic has been the focus in one of our printed “Ask the Experts” features, where our panel of Experts delve deep into the questions and concerns raised by our readers.

Join us, as we bring this particular Q&A to the blog!

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Reader Question: Why is spoiled veg toxic for guinea pigs?

“Could you explain why vegetables need to be discarded quickly if not eaten? Do they become toxic? What could happen if a piece of cucumber we forgot to discard gets eaten? My guinea pigs take and stash veggies all over the place. I’m worried about them eating overnight veggies and getting sick.”

Guinea Pig Magazine Expert, Katharine Frayling

Reply from Katharine Frayling:

“Serving healthy, fresh vegetables to your guinea pigs means they won’t spoil as quickly, giving them a longer time before starting to decay. Vegetables begin to decompose once exposed to light, moisture, temperature, air, and microbes. Feeding just enough vegetables to be eaten right away prevents them from being left lying around. You might try feeding smaller amounts more frequently so they finish what is given. Generally, if the weather isn’t too hot, wet, or cold, then vegetables should be fine overnight.”

Reply from Wiebke:

“You should only feed as much as your pigs can eat in one sitting. They should also eat grass and hay, which should make up at least 95% of their daily food intake. Even hay should be regularly changed. Spoiled or spoiling vegetables can cause digestive upsets like bloating or diarrhoea. If you have outdoor guinea pigs, be aware that leftover vegetables and pellets can attract other wildlife, including rodents like mice and rats, which significantly increases the risk of illnesses that can be passed onto your guinea pigs.”

Guinea Pig Magazine Expert and moderator of The Guinea Pig Forum, Wiebke Wiese-Thomas

Guinea Pig Magazine Expert, Abi Edis
Guinea Pig Magazine Expert, Abi Edis

Reply from Abi:

“The concern about discarding uneaten vegetables stems from the fact that they can spoil. This largely depends on the vegetable and the environmental temperature, which is why we often keep vegetables in the fridge. Overnight is unlikely to cause harm, unless it’s the middle of the summer, but uneaten fresh food should preferably be picked up at least daily.”

Reply from Dr Alison Wills:

“I think the advice to remove uneaten food is to prevent it from spoiling and then being consumed. I wouldn’t worry too much if there are a couple of bits left overnight (especially outdoors, where it’s likely cooler, depending on where you live and the time of year), but try to pick up what you can. Generally, I find that my guinea pigs don’t tend to leave much ‘leftover’, and usually, after an hour, there isn’t any evidence that the vegetables ever existed. If you’re finding a lot of waste, you could revisit the quantity you are feeding.”

Guinea Pig Magazine Expert, Dr Alison Wills

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Issue 79 is OUT NOW!

Sci-fi Geeks Salivate – We’ve Got an AI Special! What’s Inside the latest issue of Guinea Pig Magazine

Issue 79 is officially out, and it’s packed with piggy content that’s bound to make you WHEEK! But before we delve into the details, let’s ensure you have your copy in hand…

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Now, back to the important info! What’s inside Issue 79 of Guinea Pig Magazine?

Can AI Really Look After Guinea Pigs?

Can AI Really Look After Guinea Pigs?

We put it to the test! In an innovative experiment, Young Ambassador Kat is entrusting ChatGPT with the care of her guinea pigs, Smartie and Raisin!


Squeak Dreams are Made of These – The Real Celeb Piggies of YouTube!

Meet Phoebe, Roxy, Callie, and Nacho! In the world of Real Celeb Piggies, the piggies of @SqueakDreams are up there with the best. We interview their human and social media manager, Sarah Birtley.

Vet Agata Brings Us Part 2 – An in-depth insight into Reproductive System Disease

In the second part of this series, we continue exploring the reproductive system diseases which can affect sows and advance our understanding of spaying guinea pigs.

Something Is Not Quite Right About a New Cage Mate…

Find out what in our Kakazuma Comic Strip.

The Piggy Whisperer – Behaviours in Their Context. Part 5: Dominance

Guinea pigs live in a hierarchical society. Dominance behaviours are therefore at the heart of every daily interaction. Wiebke Wiese-Thomas takes a close look at these for us.

This, plus all of our regular, fantastic reader piggy pages!

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