2. It is safe for ferrets to consume large amounts of carbohydrates. FALSE. Fundamentally, carbohydrates are long chains of sugar, which is why they are such excellent sources of energy. Simplistically, there are two types of carbohydrates: those that can be digested, and those that cannot. The former category includes digestible starches and sugars, the later indigestible starches and cellulose. Herbivores have a digestive system modified to shear, crush, hydrolyze, and otherwise prepare indigestible starches and cellulose for bacterial fermentation, which takes place in the gastrointestinal tract (in various places depending on the species). Even so, the process is inefficient, and the herbivore is required to eat tremendous amounts of food to meet protein and energy needs. The ferret digestive system lacks this ability, as well as the colonies of bacteria that are capable of shearing the molecular bonds found within indigestible starches and cellulose. In short, ferrets are incapable of digesting most vegetable materials. However, during the extrusion process, hard to digest starches are converted into easily digested ones. Ferrets are animals that generally eat to meet energy needs, which means they eat until several physiological mechanisms are triggered. Here's a puzzle for you; why do ferrets that consume meat only eat a few times a day, while ferrets that crunch kibble will eat every few hours? The answer is simple: starch. Starch causes blood sugar fluctuations that spur feelings of hunger. The mechanism is simple, relating to blood sugar levels as well as the presence of a hormone, CCK (cholecystokinin). As the kibble bolus is hydrolyzed in the stomach, the resulting chyme is squeezed through the pyloric sphincter into the duodenum, resulting in the production of CCK. The gall bladder and pancreas are stimulated into releasing bile and pancreatic juice. Pancreatic juice contains bicarbonates and digestive enzymes, including lipase, protease, and amylase. Amylase is an enzyme used to break starches into complex sugars that are further hydrolyzed by specific enzymes, such as maltase, or lactase. The presence of starches in the intestinal mucosa causes additional excretion of CCK, simulating the external secretory activity of the pancreas, especially the production of amylase (CCK has several other functions beyond the scope of this discussion, including specific effects on satiety, and the stimulation of other digestive enzymes). The reason ferrets that eat kibble have to eat so frequently is threefold. First, kibble swells as it starts to be digested, so it doesn't take a lot to fill the stomach, triggering feelings of fullness. Second, as kibble is digested, it drastically raises blood sugar, reinforcing the feeling that hunger has been abated. Third, as the kibble-derived chyme enters the duodenum, it stimulated the production of CCK, which triggers receptors in the brain, shutting down the hunger sensation. When ferrets eat meat, because far less starch is present, this process takes much longer, so they eat more. Here's the rub, and why high levels of starch isn't particularly healthy for ferrets to consume on a regular basis. Ferrets that eat kibble are making the acini cells of their pancreas work overtime to try and manufacture enough amylase to convert the excess starch in their intestines into complex sugars (disaccharides: lactose, maltose, sucrose). That's the first domino. Complex sugars are converted into simple sugars (monosaccharides: fructose, galactose, glucose). Ultimately, all starch-derived sugars are converted to glucose (also called dextrose, blood sugar, corn sugar, or grape sugar). What this means is ALL the digested starch in kibble is ultimately converted into glucose (blood sugar). That's the second domino. Blood sugar levels are controlled by the pancreas, which excretes insulin and glucagon to maintain a constant level. Insulin is released when blood sugar is elevated and glucagon when blood sugar is depressed. The question is, how does a pancreas that evolved specific modes and rates of excretion of enzymes and hormones designed for an all meat diet respond to a diet suddenly rich in starches? That is the million dollar question, and the key to understanding insulinoma. The bottom line is the ferret digestive system evolved supplying enzymes and hormones to a meat-eating specialist. It was not designed to process the large amounts of carbohydrate present in contemporary dry, extruded foods (kibbles). Is this a triggering event for other disease processes, or a direct cause of insulinoma? That question is unknown, but there is little doubt a correlation exists between consuming kibble and increased rates of insulinoma, as to obesity. Even if the question of insulinoma cannot be answered, the fact that frequent feeding of a sugar-rich food directly leads to obesity, and THAT by itself makes the feeding of starch to ferrets unhealthy. Bob C [Posted in FML issue 3938]