Feeding guinea pigs and rabbits together

Sharing a hay supply between guinea pigs and rabbits is actually fine — both need unlimited timothy hay as the foundation of their diet, so that part works out nicely. The critical difference comes with everything else: guinea pigs cannot synthesise vitamin C and must get it through their food and fresh veg, while rabbit pellets contain none. If your guinea pigs are eating rabbit pellets, or a mixed blend, they'll quietly develop a deficiency. Before I point you in the right direction — how many guinea pigs and rabbits do you have, how old are they, and are you currently feeding them from the same pellet bag?

That's a really common mistake and the labelling on those 'small animal' bags is genuinely misleading. Four months on a vitamin C-deficient diet isn't ideal, but at 18 months your guinea pigs are young and resilient — switching them now will sort things out. Your rabbit can stay on the same pellets or move to a good rabbit-specific brand; he's not in the same risk category. The fix is simple: separate pellets for each species, same hay for all, and a bit of fresh veg daily for the guinea pigs. I'd go straight to Oxbow Essentials Adult Guinea Pig Food — it's properly formulated with stabilised vitamin C, the pellets are uniform so they can't selectively eat the tasty bits and skip the nutritious ones, and it's the brand most small-animal vets in the UK recommend. A 1.8kg bag typically lasts two guinea pigs around six to eight weeks.

Skip the water drops — vitamin C degrades very quickly in water, especially in light, so by the time they drink it most of the benefit is gone. It also makes the water taste odd and some guinea pigs drink less as a result, which causes its own problems. The pellets plus fresh veg is the right approach. A small piece of bell pepper daily is one of the best natural sources — a thumbnail-sized chunk each covers their needs easily. Leafy greens like romaine lettuce, curly kale, and parsley are good rotation options. Just avoid iceberg lettuce and go easy on spinach and kale if feeding daily as they're high in calcium.

One bag is genuinely fine. Timothy hay is the gold standard for both species — it supports healthy digestion and keeps their continuously growing teeth worn down properly. The only nuance is that young rabbits under six months do better on alfalfa hay, which is higher in calcium and protein for growth, but your three-year-old rabbit is well past that stage. For adult rabbits and guinea pigs of any age, straight timothy hay works perfectly. If you want a practical tip: Oxbow Western Timothy Hay is consistently good quality with low dust, which matters if anyone in the house has allergies or if the animals are kept in a living space. Buy the largest bag that fits your storage — it keeps well in a cool, dry spot.