Ferrets, like cats, are obligate carnivores. This means they absolutely require meat in their diet. A ferret-appropriate diet should have a high level of fat as its main source of calories, and also be rich in highly digestible meat-based protein. Vegetable protein is poorly digested by ferrets, and can actually lead to certain medical issues, such as bladder stones, skin diseases, GI disease and poor growth. It is also important to note that ferrets cannot digest fibre, so high levels of grains should also be avoided when choosing a diet for your new pet.
The absolute best diet for a ferret is whole prey foods, such as mice and rats, similar to a snake. Understandably, many owners may not feel comfortable feeding that to their pet, so the next best option would be either a specialized ferret diet made specifically for their nutritional requirements or a high-quality kitten food you would find at a vet clinic. If you do buy a special ferret diet, make sure to check the ingredient list that it is appropriate and isn’t fish based. They need the best quality nutrients because they have a very short GI tract and simple gut bacteria, or “flora”, so there are only 3-4 hours for their body to digest their food and absorb its nutrients.
If you want to give your ferret a treat, the best option would be a small piece of high-quality meat, such as chicken or turkey. Avoid the ferret-specific treats on the market, because most of them have no meat in them at all, but rather mostly grains and sweeteners. Feeding this to a ferret can be quite dangerous to their health. Even though they may like the taste of sweet foods like fruits, it is best not to feed them those as treats either.
It is a very good idea to allow your ferret to experience a variety of different foods at an early age so they become accustomed to different flavours and diets. If you change food or flavours abruptly with an adult ferret, that could potentially make them sick.
If ferrets are being fed an appropriate high-quality diet, they likely won’t require any supplements other than maybe a fatty acid supplement to help with dry coat and flaky skin.
Fresh water should be available to your ferret at all times and changed regularly.