Since you have such strong feelings about veterinary nutrition and prescription diets, I will be looking forward to the post you submit here AFTER you've completed the second year veterinary clinical nutrition and gastroenterology couses. I'm sure the other veterinarians who frequent this blog regularly will be just as intrigued.

Quite. Where exactly is the "proof" on catinfo, as opposed to rhetoric? I am tired of the 'dry food kills cats' argument being presented entirely sans data. My anecdoate is as good as anyones and it suggests dry food is fine. The right diet for a specific cats might be dry or wet depending on their requirements.

[fifth attempt, seriously I am getting CAPTCHA rage]

Exactly (what the other posters said). My dog had blood coming out of both ends for a good year as I tried high-end food after high-end food after homemade meals after raw food. Only when she was put on Hill's I/D did her tummy settle down, and she's been a healthy, happy pooch ever since. Hill's is a friggin' miracle in my book. May not work for everyone, but I certainly won't quit buying it.

There's also a very, very small mark up on commercial pet foods, so your vet is not getting rich off of them. The mark up barely covers the cost associated with ordering and stocking the foods (so much so that many vets are turning to vetcentric and other such services-its just too much hassle).
Your vet recommends foods based on what they feel, after 8+ years of higher education and X number of years of experience, is best your your pets medical condition. But hey, if you know better after reading on a few websites that probably have information from dubious (i.e. not peer reviewed) source, you go right ahead. Good luck with that.

I think we can assume good will on the part of those of us who come here seeking information -- veterinary professionals and laypeople alike. We can agree that vets do not get up in the morning twirling their mustaches and scheming to retire early on the profits from dog food. We can also agree that lay status itself does not disqualify the resulting opinions, and that not all laypeople obtain their information on the Internet from Joe-Bob's Pet Tips.Com. No need to get snarky either way.

Research leads some of us to conclude that dogs and cats are not being best served by diets (commercial or homemade) containing large amounts of grain and other carbohydrates. Carbohydrates are supplied in commercial pet foods as an inexpensive source of "energy" (calories); they are necessary to make the kibble extruder machines function. This being so, the ingredients list on the cans and bags of pet food might cause a bit of concern.

With regard to Hill's specifically, it seems the corporation has ignored some research relative to more recent evidence indicating protein-sparing diets for kidney patients may be ineffective or harmful, and when challenged has been less than forthcoming about the rationale for its KD diets.

Maybe the "kickbacks" allegation refers to the practice of treating vet staff to lunch (by food manufacturers and drug companies alike) and the ubiquitous presence of some pet food manufacturers in vet school nutrition programs. Not wrong on its face, but interesting to note among other facts when evaluating information.

- Catherine
Some quick research notes below:

According to The Waltham Book of Dog and Cat Nutrition, "There is no known minimum dietary carbohydrate requirement for either the dog or the cat.”

In the early 90s one in 400 cats was found to have diabetes. Today the rate has doubled. (Deborah S. Greco, DVM, PhD, Diplomate ACVIM, Associate Professor at the College of Veterinary Medicine and Biomedical Sciences at Colorado State University.) "The cat is an obligate carnivore and as such is unique among mammals in its insulin response to dietary carbohydrates, protein and fat.... (T)he cat is uniquely adapted to a carnivorous diet and is not metabolically adapted to ingestion of excess carbohydrate."

Purina research shows that reducing the amount of dietary carbohydrate in diabetic cats' diets will get more than half of them off insulin. (Purina introduced a DM, a "low carb" prescription food specifically to address this.)

In the Journal of the American Veterinary Medical Association. Debra L. Zoran, DVM, PhD, DACV addressed feline conditions that might be related to inappropriate consumption of foods high in dietary carbohydrate, including obesity and diabetes: “Dietary recommendations extrapolated from recommendations for humans and dogs are to feed affected cats diets high in insoluble or mixed fiber. However, with the increased understanding of unique protein and (carbohydrate) metabolism in cats, these recommendations have been challenged. High-protein, low-(carbohydrate) diets and low-fiber diets are highly beneficial in the management of cats with diabetes, resulting in a reduction of greater than 50 percent in the amount of insulin required in 8 of 9 cats in one study. In another study, complete cessation of insulin administration was reported for one-third of the cats. In another study, 49 researchers reported that contrary to what is observed in dogs, cats fed diets containing soluble or insoluble fiber had altered glucose tolerance. Another study reported that feeding typical adult maintenance diets to cats resulted in development of greater postprandial hyperinsulinemia, even in cats with normal body weights, compared to cats consuming a high-protein diet...reduction in dietary starch will substantially reduce the insulin requirement (endogenous and exogenous) in affected cats.”

“Canine Nutrition”, DS Kronfeld, University of Pennsylvania, School of Veterinary Medicine, 1972?, excerpt from article, “Some Nutritional Problems in Dogs”, page 32-33:
“No lower limit or minimal requirement for carbohydrate has been established in the dogs. Ketosis and associated sodium depletion occur in humans suddenly shifted to low carbohydrate diets. Dogs are much more resistant than humans to ketosis when fasted and fed 100% fat. Sled dogs fed a high fat (66% energy) and zero carbohydrate diet at twice maintenance has very low blood levels of acetoacetate and betahydroxybutyrate 3 and 9 weeks. There is no evidence that dogs have an essential nutrient requirement for glucose, using nutrient in the strict sense of something assimilated from the diet. Tissue utilization of glucose accounts for about 25% of the total resting metabolism in dogs and other animals. Clearly this can be synthesized from nutrient precursors of glucose, (e.g. amino acids and glycerol, in dogs fed zero carbohydrate). In this respect, dogs resemble ruminants, chicks, rats, and cats. Even in man, the metabolic changes that immediately follow dietary intake of carbohydrate deprivation abate with time. Thus, there is no minimal daily intake of carbohydrates recommended for man. It has been suggested that some unassimilated carbohydrate is beneficial mechanically in facilitating regular bowel movements. Regularity is synonymous with health in the eyes of anally-oriented people. The anthropomorphic projection of this ideal to dogs has no established medical basis. The small, foul smelling and infrequent productions of a dog fed a low fiber diet may be less desirable than the bulky, relatively pleasant herbivore-like scatterings of dogs fed high fiber diets. Or they may be more desirable. This is a matter of esthetics.”

The National Research Council (NRC), which sets the standard for nutritional needs of dogs, does not list a carbohydrate requirement. They do include a long list of amino acids, and these are found complete in animal proteins. Fat is also listed, along with specific minerals. Meat, bones, organ meat, dairy and eggs can supply all of these requirements
Dogs and cats have the internal anatomy and physiology of a carnivore (Feldhamer, G.A. 1999. Mammology: Adaptation, Diversity, and Ecology. McGraw-Hill. pg 260.). They have a highly elastic stomach designed to hold large quantities of meat, bone, organs, and hide. Their stomachs are simple, with an undeveloped caecum (Feldhamer, G.A. 1999. Mammology: Adaptation, Diversity, and Ecology. McGraw-Hill. pg 260.). They have a relatively short foregut and a short, smooth, unsacculated colon. This means food passes through quickly. Vegetable and plant matter, however, needs time to sit and ferment. This equates to longer, sacculated colons, larger and longer small intestines, and occasionally the presence of a caecum. Dogs have none of these, but have the shorter foregut and hindgut consistent with carnivorous animals. This explains why plant matter comes out the same way it came in; there was no time for it to be broken down and digested (among other things).