Guinea pigs and rabbits look like close feeding cousins, but one deep difference separates their diets: a guinea pig cannot manufacture vitamin C. Like people, guinea pigs lack the enzyme that finishes vitamin C production, so every bit of it must arrive in the food bowl. Rabbits make their own, which is why rabbit pellets are formulated with little or no added vitamin C at all.
The Shortfall That Causes Scurvy
Fed rabbit food week after week, a guinea pig's vitamin C stores quietly drain, and scurvy follows. The signs tend to creep in rather than crash in: a coat that turns rough and thin, tender or swollen joints that make the pig reluctant to move, sore gums, loose teeth, slow healing, and an appetite that fades as eating becomes uncomfortable. Young, pregnant, and recovering pigs run short fastest because their bodies are spending vitamin C as quickly as it arrives. A pig showing several of these signs needs a veterinarian promptly, because scurvy that is caught early is far easier to put right than scurvy that has reached the joints and teeth.
More Than One Nutrient Is Wrong
Vitamin C is the headline problem, not the only one. Rabbit pellets balance protein, fibre, calcium, and energy for a rabbit's digestion and growth pattern, and those ratios sit wrong for a guinea pig even before the vitamin gap is counted. Some rabbit feeds, particularly medicated feeds intended for young meat rabbits, have historically included additives that are unsuitable or unsafe for guinea pigs, whose gut bacteria react badly to ingredients a rabbit tolerates. Seed-heavy rabbit mixes add a further mismatch: guinea pigs pick out the rich pieces, eat a lopsided diet, and wear their constantly growing teeth unevenly.
What a Guinea Pig Bowl Should Hold
The safe pattern is built from three parts. First, unlimited grass hay, available around the clock, because it drives the chewing that wears the teeth down and keeps the gut moving. Second, a measured serving of guinea pig pellets with added vitamin C, following the portion guidance for your pig's age and weight rather than filling the bowl to the brim. Third, about a cup of fresh vegetables daily, chosen partly for vitamin C: bell peppers of any colour are a standout, and leafy greens, broccoli florets, and small pieces of kiwi or orange all contribute. Weigh your pig weekly on kitchen scales, because steady weight is the quickest proof that the corrected diet is landing well. Vitamin C in pellets fades with storage, heat, and light, so buy smaller bags, keep them sealed and cool, and do not rely on vitamin drops in the water bottle, which degrade quickly and can put a pig off drinking.
If Rabbit Food Has Already Been Served
One accidental meal of rabbit pellets will not cause scurvy on its own, because the deficiency builds over weeks, not hours. Simply switch back to the correct diet, make the change across two or three days if your pig is a fussy eater, and watch appetite, movement, and droppings over the following week. If the rabbit food was the main diet for several weeks, or your pig already moves stiffly, eats less, or has a rough coat, book a veterinary check rather than waiting to see whether fresh vegetables alone repair the shortfall. KinsLe's Care Teams helps the whole household hold the corrected diet steady, because each feeding duty names the guinea pig pellets, hay top-up, and vegetables for that day and is ticked off with a timestamp once it is done.