Yes, you can feed kiwi to a guinea pig but moderation is the key because the kiwi fruit is high in sugar content. Even though they are also a good source of vitamin C it is important to limit the intake of this fruit as too much can cause digestive and other health issues.
As mentioned above moderation is key and also small amounts when you give this fruit as only a treat to your guinea pig.
Even if your guinea pig loves this fruit is important to note that there are many other fruits and vegetables that are better suited for their diet compared to kiwi’s. If you give too many of this fruit to your piggy it will cause weight gain, digestive issues and possibly other serious health issues after time.
The most important thing to do is provide your guinea pig with fresh high quality hay and fresh water at all times.
On top of that it is also a really good idea to provide your guinea pig with pellets from the pet store that are fortified with vitamin C.
A general rule of thumb for all fruits and vegetables is that a sensible amount should be given and if you are unsure please contact your veterinarian or your local pet store employee.