by Bob Church
Three people asked me to comment on the idea that Cherrios and chopped vegetables and fruits are good ferret treats. It appears to have been a question in a recent issue Ferrets magazine. I haven't read the original article yet, so can't comment directly. But I am happy to offer my opinion on the matter in a general sense.
When discussing the diet of the ferret, I find it useful to forget that our pets are domesticated wimpies, and instead concentrate on the polecat progenitor. After all, ferrets ARE polecats in much the same way that dogs are wolves and humans are just big apes with an attitude and carrying weapons. So you have to ask yourself two basic questions. 1. What do polecats eat? 2. What is available to feed ferrets that approximate the polecat diet? You cannot easily answer the second question without answering the first. Well, you can bottle ferrets into bubbles and collect every last molecule of waste products and look to see what happens when you fed them certain foods. When finished, you can see if the ones still alive can reproduce. That works, if you have the time, money and a number of disposable ferrets. But outside of that, about the best thing you can do is to study what the wild progenitor of our domesticated polecats eat and offer an approximate diet to ferrets.
The number one thing you notice when investigating the polecat diet is they do NOT eat grains, especially processed cereal grains. Some nutritionists have argued that polecats DO eat some grains that are found in the gastrointestinal tract of prey animals, but realistically, that is more than stretching the point on three counts. First, wild European polecats are anuran specialists; they tend to eat a LOT of frogs and toads. So much so that in many parts of Europe, anurans constitute the majority of the yearly diet. I don't know a lot of frogs and toads that eat cereal grains, although I admit some have a fondness for algae. Second, there is a concept called optimal carnivory, which suggests carnivores eat the most nutritious part of the prey carcass FIRST, just in case they are chased away from their meal. Polecats will generally eat the brains first, then turn the animal over and start consuming muscle groups, heart, liver, spleen and kidneys, and then, if enough time exists, they MAY eat the gastrointestinal organs. In other words, there is little or no guarantee the polecat will get to eat those "processed" grains found in the rodent or lagomorphs gut.
Finally, how much grain can a mouse hold in their intestines? In relationship to body weight, not a lot. You don't have to be able to do quadratic formulae in your head to know the percentages are minor, and an insignificant part of the diet.
Do polecats eat fruits and vegetables? Ferrets do; we have all heard stories of ferrets stashing potatoes and devouring broccoli and going bonkers over raisins. Well, ferrets have a built-in desire to eat sugars, and polecats are no different. Sugars are the currency on which the economy of the body runs. Sugars represent calories, and just about every mammal has a predisposition to crave sugar (and salt). Polecats have been recorded eating honeycomb (every year skunks raided my dad's hives), and will certainly consume fruits when encountered. But if you look at the physiology of the ferret, you discover they can manufacture sugar from protein, without any adverse health problems. Humans can't do this for very long; neither can most mammals. In most mammals, ketones and other breakdown products of protein glucogenesis can severely damage the kidneys and other organs. In humans, it can lead to "rabbit fever' and death. But the ferret is absolutely immune from the effects, and can obtain their caloric currency from protein alone, which simply means carbohydrates are such a small aspect of their diet that they don't make a difference.
To be able to get nutrition from a vegetable, you must first be able to grind the food to a pulp; ferrets cannot masticate their food--they cut it into chunks and bolt it like a cat, and their teeth are formed into cutting blades rather than grinding surfaces. Then you must be able to have a prolonged gastric digestion, but ferrets have a gastric emptying time measured in minutes (designed to process proteins as soon as possible so the stomach can be rapidly refilled). In order to break down the cellulose and get to the goodies, you need a long, complex intestine, and a region inhabited by symbiotic bacteria; ferrets lack a visual caecum and have a short, simplistic intestine. Since cellulose sucks up a lot of water, herbivores need an efficient water-absorbing large intestine to keep water requirements as low as possible; the ferret large intestine is hardly different from the small, and is not very efficient at resorbing water. The point of this exercise in ferret digestive physiology is that ferrets are incapable of obtaining nutrition from minced vegetables, and can only obtain minor amounts of nutrition-mostly sugars-from fruits.
Still, not wanting the reputation of a fuss-budget, what about the quality of the foods as TREATS? In tiny amounts, fed infrequently, they are not life threatening. So if your healthy ferret really likes them, let them have some enjoyment. I wouldn't feed them to ferrets with insulinoma, gastrointestinal diseases, or immunity problems (especially the Cherrios). I would sincerely worry about the impact Cherrios and fruits have on the teeth, especially for their role in the development of caries or tartar, as well as their impact on ferrets with insulinoma. They are absolutely NOT the best treats you can come up with. But they can hardly hurt a healthy ferret if fed in small amounts, such as a half a Cherrio or raisin at a time, or a couple of small chunks of melon (which could be marketed as a ferret laxative). If your ferret is eating the equivalent of three Cherrios a day, I would consider it excessive.
Better treats, and just as popular (once ferrets get used to them) are meaty or oily foods (ferrets crave fat as much as sugar or salt). Mine go bonkers over dried rainbow trout or beef, chunks of beef heart, boiled beef ribs and the ever popular frozen mice. Other treats include chicken baby food (I WANT them to love it because I use it to feed them medicines, so I give it as a treat), boiled chicken necks and backs (the bone is harmless), flaked tuna, boiled egg, or tiny chunks of cheese. The hard, fibrous fat you cut off your steak is a perfect treat, once you teach your ferret it is edible. It's a tough connective tissue, so as the ferret pulls and cuts it, it cleans the teeth. It is full of fat (and essential fatty acids and vitamins), so it is nutritious. No other food as many calories per pound, so it is better than cream for helping ferrets get their weight back after surgery or illness. Plus it satisfies the ferret's instinct to chew. It may be impossible to convince an older ferret of its value, but if you start with a kit, they will rapidly become fanatical over the stuff. You can try chicken fat with older ferrets, which isn't as fibrous so you may not get as many benefits for chewing and teeth cleaning, but since a lot of ferret food uses chicken, it might be easier to convince a ferret to try. Or you can try my favourite trick; I get the ferret hooked on chicken fat, then feed them some beef fat that had been stored in chicken grease. It fools the ferret into thinking the beef is a chunk of chicken.
By the way, one of the main reasons ferrets "crave" vegetables, crackers, breads, and Cherrios is because of the odour. Ferrets who eat dry kibbled or extruded foods are olfactory imprinted on cooked carbohydrates. The craving a ferret may display for a cracker or a chunk of potato may have more to do with subsisting on a commercial diet rather than because it is a "natural" behaviour. Also, ferrets have instincts to hunt and kill, but they have to be TAUGHT what animals are suitable for those purposes by their parents, which include human owners. If a kit sees you eating a carrot, and you give them a piece, you are in essence TEACHING them carrots are good to eat. That is exactly HOW polecats learn what foods are meant to be consumed; the mommy polecat teaches them by eating some and offering the rest. I have investigated a number of cases where a person will claim their ferret loves veggies, and in almost every case, the human allowed their ferret to nibble or eat the vegetable as a kit. Of course they will like the food as a treat when older; they were taught it was a good food when growing up! That is hardly a normal behaviour. You can use this technique to teach ferrets to try some foods. I bring the ferret up to my face so they can clearly see what is going on, eat some of the food, then put some in their mouth. It doesn't always work with the older ferrets that are severely olfactory imprinted, but it works great with the young ones.
Personally, I would need some convincing before I would say Cherrios or vegetables were good treats. Small chunks of fruit are somewhat better, but not on my "A" list. They may not be bad in a healthy ferret if fed infrequently in small amounts, but there are so many foods which are superior.
One thing I forgot to discuss is dried meats. I offer beef jerky, dried shrimp and fish (mostly salmon or trout), and chicken or turkey jerky to my ferrets as treats, which they love. The Late, Great Bear would bite your finger if you tried to take his beef jerky away! I don't offer commercial products manufactured for humans because of the high salt content, and the seasonings are unnecessary. I make my own simply by cutting the meat into strips and drying it in a dehydrator (you can get one for about 50 bucks). Also, I don't dry it to a rock-hard consistency, just until it is tough, but still bendable. I package the dried meats in ziplock bags and store them in the freezer until needed. I only thaw what is needed at a single time. This method has completely eliminates problems with fungus or other spoilage.
Even so, the ferret may require extra water to process the dried meats, which is ok as long as your ferret is healthy (discuss dried meats with your vet if your ferret has cardiac, kidney or water retention problems). Usually, I crumble some up and add it to chicken baby food for my sickies. As a treat it is wonderful, but the calcium/phosphorus ratio is off, so don't feed it expecting it would be a complete meal. Kits raised on a diet of beef jerky would likely end up with rickets.
One finally word of warning. Feeding beef jerky-even home-made, unseasoned stuff-results in extremely dark scat which could mimic tarry poop caused by gastric bleeding. Muscle meats are full of myoglobin, which has a lot of iron. It's the iron in the blood which makes stools turn black and tarry, and a diet of concentrated muscle tends to do the same thing. If your ferret gets black stools from eating dried beef, it won't hurt them. Aside from the presence of fur and bone, wild carnivore scat can be distinguished from pet poop because of the dark color. However, if your ferret is prone to bouts of ulcers, and it is important to watch the stools for the first sign of bleeding, I would suggest skipping the beef jerky and sticking to dried fish or chicken. The beef won't harm them; it just makes it hard to watch for the symptoms of bleeding.