Bob C: Diet in the Wool Questions (6) Q: If carbs are so bad and you don't think ferrets should eat them what do they eat instead? I thought the ferret had a super fast metabolism aren't carbs are needed [for energy]!? Q: I don't understand if ferrets need glucose to live, how can they get it from protein? If they don't eat carbohdrytes, can they get malnourished? Q: Our ferrets should do as much exercise as possible but the fact is that most of them spend long hours caged, so again, they won't need the same amount of nutrients or the ratio could vary [from wild polecats]. A: There are those of us that think, those that exercise, and those that think of exercise. As for me, thinking IS exercise. Wait, I just had a thought crap, now I m all sweaty and tired and I need a nap. Excellent, profound questions! Ok, food consumption basically accomplishes two functions: it provides energy for life and it provides materials for growth, repair, maintenance, and fighting disease. The ferret's energy needs are expressed as caloric requirements, while material needs are expressed as nutritional requirements. If a ferret were a car, then the energy needs would be the gas, while the material needs would be the parts, oil, and supplies used to build the car, as well as keep it in repair and running. The nutritional requirements of ferrets vary somewhat during their lifespan and they include water, protein and associated essential amino acids, fat and associated fatty acids, and various minerals and vitamins. Yes, energy is also a nutritional requirement, but I'm keeping it separate for this discussion. Ferrets have no--as in zero--carbohydrate requirement, meaning they can live their entire lifespan without a need to consume them. This reflects their evolutionary history; polecats might consume carbohydrates contained within the gastrointestinal tract of their prey, and I am sure they consume some fruit in a limited amount on a seasonal basis, but the amounts ingested over a year is less than 5% of their diet and a portion of that is indigestible. For much of the year, such as when polecats specialize on amphibians, or in the early spring when the body condition of prey species is poor and available prey is at the yearly low point, the carbohydrate being consumed is only a fraction of a percent. The nutritional requirements of growing kits are very high in order to fuel and supply their steep growth curve. This is why kits eat--and poop--so much; they are running food through their digestive system about as fast as they can. This is also why many nutritional studies show carbohydrates in the diet increase size and weight of growing carnivores; the extra energy in the food (when compared to a protein source of energy) changes the slope of their growth curve, maximizing growth and size. This makes a big difference when growing mink for their pelts, but they hardly live longer than a single season so the long-term effects are considered unimportant and are largely unknown. Once a ferret has reached adulthood, nutritional requirements more-or-less stabilize as the body goes into maintenance mode and only worries about warding off disease, maintaining the body and replacing worn-out parts. At this time, if a ferret needs a little more nutrients, it can eat just a little more and things are fine. It is possible older ferrets have slightly increased or decreased nutritional requirements, depending on the nutrient, but if so, the evidence is thin. There is no compelling evidence that suggests a healthy ferret has a decreased protein requirement as they age. During growth spurts and pregnancy, a ferret will generally eat more food, meeting their nutritional needs provided the food is adequate and nutritious. However, many ferrets become anorexic during illnesses and if the illness lasts a considerable length of time, they often fail to meet their nutritional needs. Frequently, these ferrets are thin, light, and weak: all signs of mild to moderate under-nutrition, or even malnutrition. There are basically four degrees of nutrition: malnutrition, under-nutrition, adequate nutrition, and over-nutrition. Malnutrition is when you don't have enough nutrients for the body and it is endangered as a result of self-cannibalism; that is, the body is utilizing its own tissues for energy and other needs (sorry, losing weight is not the same thing; you ARE cannibalizing fat, but that doesn't make you malnourished--but it was a good try!). Under-nutrition is when you don't have quite enough nutrients, so you use body reserves to make up the difference and the body is not being cannibalized. Adequate nutrition is when you have the exact amount of nutrients and are not using your reserves. Over-nutrition is when you have more nutrients than you need so that many are left over and wasted, or converted to fat. If the nutrition problem is related to starving, that is, both a protein and calorie deficiency, then it is called marasmus. If the malnutrition is due to a lack of protein in the diet, but the ferret has enough calories (generally from carbohydrates), then it is called kwashiorkor. It is important to note that the health of the ferret is not an issue with under-nutrition; healing and growth could be a bit slower, but as long as the condition doesn't develop into malnutrition, the ferret will recover quickly as body stores are replenished. Remember, in under-nutrition, the ferret is not getting enough nutrients, but can make up for the loss by utilizing body reserves. That means that even though the body reserves are being depleted, the ferret is meeting their nutritional obligations. In terms of the nutritional requirements during exercise, I am sure there are differences, but the real question is, How significant are those differences? In terms of micronutrients, proteins, or fatty acids, they would be a bit more, but not outside a few more mouthfuls of food per meal. Ferrets certainly have the ability to manage those differences on their own simply by eating a little more or less. The real difference would be in terms of energy needs. [Posted in FML issue 4595]