I have two ferrets called Teddy and Otter who are very cool pets but they're teeth are starting to go green and grey. Please tell me whats going on and what i should do.

What are you feeding them?

i feed them meat, ferret and cat dried food, salads, sometimes butter and a tinsy bit of melted chocolate.

Is that bad?

I would stick to the meat and ferret food, why on earth are you giving them butter and chocolate?
Ferrets are obligate carnivore meaning they can only digest meat

Chocolate is poisonous for ferrets.
Ferrets are MEAT eaters, do not feed them salad stuff.
The meat and ferret biscuits are sufficient. Always supply fresh water.
It does sound like the teeth are rotting though
A vet check would be advisable.
RAW bones are good for dental hygiene.
Butter (while I know they love the stuff) is loaded with salt, another thing not good for them unfortunately (I very very very occasionally give mine a lick of butter) and a lick is all!!! Unsalted butter is sometimes a temporary helper to put weight on an underweight ferret (high in calories)

how long have you had the ferrets? It sounds like they have been given dry food only, Id suggest giving them chicken wings and chunk meats so they have to really chew. I agree with others dont give them chocolate as its bad for them but you can give alittle oil (sun flower) on their meat every few days maybe twice a week, they'll love it.

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Everyone is entitled to be stupid, but some abuse the privilege.

My ferrets are fed mostly dried food (95%+) and their teeth are good and clean and white.
Raw bones can help with teeth.

\Raw bones help alot. I have seen it in 100% dry fed ferrets at 6 months old, their teeth are so bad.

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Everyone is entitled to be stupid, but some abuse the privilege.

My Ferret refuses to eat meat. she eats the crunchy ferret kibble(the dried up meat source) high in protein, but she loves chocolate, penut butter and all the stuff she should not have. She favors Honey Nut Cherios. All that extra crap could cause the teeth issues so I keep a good eye on her teeth. Can't get her to eat meat at all, any kind of meat. I'm going to look into the way the english in London feed their Ferrets I've heard that they feed them live food such as chickens(baby chicks). I'll be researching that to find out for sure after all Ferrets are carnivores. The thought of my sweet little Feebie attacking and killing then getting bloody sure does not appeal to me at all but if it will keep her healthy I may be willing to put a tarp over her cage and let her hunt. Crystal

DOC - day old chick - are usually bought FROZEN.
Feeding live prey in UK isn't legal unless it is detrimental to the animals health otherwise.