Vitamin C is of utmost importance to guinea pigs, as they are unable to manufacture their own (much like humans). Without enough vitamin C in their diets, guinea pigs can become very ill with scurvy. The amount of vitamin C required varies somewhat depending on the reference source used, but most guinea pigs probably need about 10-30 mg/day. Pregnant, nursing, young, and ill guinea pigs need more.
- If you feed a good selection of vegetables high in vitamin C along with a good, fresh guinea pig pellet, you can probably meet the vitamin C needs of the average guinea pig.
- Many guinea pig pellets have vitamin C added but, unfortunately, vitamin C is quite unstable and will degrade over time. Keeping the pellets in a cool dark place helps preserve the vitamin C. You can also get pellets with a stabilized form of vitamin C.
- The best way to supplement with additional vitamin C is to use vitamin C tablets. You can buy vitamin C tablets specifically for guinea pigs (e.g. Oxbow's GTN-50C), or buy human chewable 100 mg tablets (note: make sure you are getting just vitamin C rather than a multivitamin formula). A quarter of a 100 mg tablet daily is a recommended dose for most adult guinea pigs. The guinea pig tablets are 50 mg, but since vitamin C is a water-soluble vitamin, small excesses over that daily requirement are easily excreted. Many guinea pigs will take the tablets like a treat and eat them, or they can be crushed and sprinkled on vegetables or pellets.
- Vitamin C can be added to the water, but there are problems with this method. The vitamin C quickly loses its potency in water (a fresh supply must be made at least daily, if not twice daily). Also, guinea pigs may refuse or reduce their consumption of water with added vitamin C due to the taste, and this may lead to other health problems. It is also very hard to know if your guinea pigs are getting enough vitamin C using this method of supplementation. Feeding a variety of fresh veggies high in vitamin C and/or supplementing directly with tablet forms of vitamin C are better options.