If you want to know what ferrets eat, the best thing you can do is look at its closest wild relatives; the black footed ferret in the US and the European polecat.
A polecats meal can consist of small rodents like mice, rats voles and rabbits. Amphibians like frogs and toads are also and the menu. A smaller part of their diet, let’s call it their snack list, consists of small birds and insects. Any kind of soy, wheat, rice or other grain they ingest has already been digested by the prey animal. In other words, your fuzzy is as much a carnivore as a tiger.
They eat the whole prey. Meat, organs, fur, feathers and bones.
If they can get their paws on bird eggs, they'll happily devour them as well.
90% of the meals of the black footed ferret consist of prairie dogs. Which is quite amazing considering the prairie dog is about the same size. They attack them at night in the burrows when the prairie dogs are asleep.
Other animals they eat are small rodents and reptiles and also eggs.
So now you know an answer to the question 'what do ferrets eat in the wild'. Next, you’ll want to look at a ferrets anatomy.
Their intestinal tract is about five times their body length. If you compare this to a cats, which is also a real carnivore, their intestinal tract is ten times its body length.
As a result, food takes about 3 hours to go from the food dish to the litter box. Which is very short. With a cat it takes almost twice as long. This means the food needs to be easy to digest as it passes through the body so quickly. Anything a ferret eats has to have a high level of fat and animal protein to keep the fuzzy healthy.
Because their intestines do not contain the necessary bacteria to digest complex carbohydrates. Simple carbohydrates like sugar (yummy) and starches can be digested.
In other words, if you feed your fuzzy a bean, 3 hours later there will be an unchanged bean in the litter box.
As their little bodies don't know what to do with this kind of food, it can cause blockages. Meaning you'll have to rush your fuzzy to the vet, hoping for a happy ending.
Now you know what do ferrets eat in the wild, you'll have a better understanding of what you can and can't feed your domesticated ferrets.