Advanced Nutrition and Your Dog
Bob Fritz, Animal Naturals
The Case for Scientific Canine Nutrition. Human-grade dietary supplements, formerly reserved for pro athletes and hospitals, are powerful tools for increasing canine performance and health. This seemingly recent breakthrough--actually decades old--is worthy of serious examination by animal health professionals. A review of the scientific literature reveals a long, yet little known record of effectiveness.
The use of specific human-quality dietary supplements for dogs may seem new. However, this is not true. Only the widespread application of these "super supplements" for dogs is recent. Actually, human-quality supplements have been used on dogs for many decades. For 70 years, teams of scientists at prestigious universities have established the ability of certain nutrients to enhance canine performance and health to unprecedented levels.
If such convincing evidence of the remarkable effectiveness of super-supplements exists, why haven’t you heard about these breakthroughs until now? There are two main reasons.
Reason 1, most of these studies use dogs as test subjects for humans. In other words, dogs were "animal models" for providing insights into human metabolism. Although numerous, these studies generally are hidden in obscure scientific journals. Since these journals pertain to human metabolism, some do not even use the word "dog" in the title. Moreover, some studies are so old they don’t appear on modern computer searches.
Reason 2, veterinarians, the link between nutritional research and you, are largely unaware of these discoveries. Understandable when you recognize that veterinarians are rewarded for practicing medicine, not reading isolated scientific journals outside their field. And for good reason--this rapidly evolving area is not taught in veterinarian school, nor is it required reading after graduation.
Medical Research (1600 Until Present) Since at least the 17th century, dogs have been used to study digestion and absorption. In 1816 the noted French scientist Dr. Magendie studied the effect of feeding sugar, olive oil and water to dogs, resulting in nutritive failure. Dogs have a long history of use as models for modern advances in insulin therapy, heart transplant and other medical developments. Significantly, much of the fundamental understanding of the metabolic alterations caused by infection, burns and trauma derive from canine models.
Medical Foods, powerful and specialized nutritional tools for meeting exceptional metabolic demands, were first successfully tested on dogs. In 1910, Drs. Abderhalden and Loewi examined the efficacy (scientific validity) of feeding predigested proteins to dogs, decades before this was standard for stressed humans., Building on this pioneering canine work, medical notables such as Drs. Abbott and Rose continued to develop medical foods, which in time, became "defined" formulas.
The primary organizing principal of medical foods is their predigested nature. That is, energy sources that are partially predigested into smaller, more easily usable molecular units. Predigested nutrients offer important advantages to stressed individuals. In addition to protein, predigested carbohydrates and fats were also tested on dogs with similarly positive results.
The first medical food formally defined was likely by Dr. Elman in the early 1940s, and was used to boost survival rates in premature infants and burn patients. Medical foods have evolved into many variations used to treat conditions ranging from post-surgery to food allergies to digestive diseases. The primary recipients of medical foods are hyper metabolic. In other words, individuals with abnormally rapid metabolic rates which cause wasting of muscle tissue. These individuals typically have energy and nutrient needs 30% to 200% greater than normal, but often have depressed appetites and lowered digestive capabilities. To these individuals, predigested medical foods are literally lifesavers.
NASA Space Foods (1962-1970) The next major advance occurred in the early 1960’s in conjunction with the NASA manned space program. At the time, space flight was unknown and terrifying. Little was understood about how the body would respond to weightlessness. Dr. Winitz and others took medical foods out of hospitals and investigated their benefits on another stressed population--astronauts. This was a major leap forward because it marked the first time medical foods were used to enhance performance and health, not fight disease or muscle wasting states.
Results of this research were positive and highly significant. As one example, a group of 24 healthy young males, eating 2,100 to 3,700 calories in medical foods, were closely monitored. The following benefits of medical foods were noted.
High nutrient density. Medical foods are extremely concentrated in nutrients. With virtually no fillers or food bulk, they are 2-5 times more concentrated than ordinary foods.
Extreme ease of digestion. Since the best medical foods contain energy sources that are partially predigested, less digestion is required. This is very important in stressed individuals who often have reduced ability to digest ordinary foods.
Greater absorption. Predigested energy sources are absorbed at high rates. And, absorption is generally very rapid, often appearing in the bloodstream within 12 minutes. This rapid availability of energy and nutrients is highly advantageous to stressed individuals.
Lowered fecal output. The "low residue" and enhanced absorption of medical foods translate into greatly reduced fecal output. The amount of feces may be decreased by half. This reduction is important in dogs during stress conditions.
Flexibility. These formulas can be easily modified and tailored according to specific needs. Portability is nearly total, and taste properties can be adjusted to please almost any palate.
Positive nitrogen balance easily achieved. Studies support the ability of the combined advantages of medical foods listed above to combine to produce a state of positive nitrogen retention. Positive nitrogen balance refers to the body’s status of potentially building more tissue and vital compounds than are being broken down (anabolism). Without medical foods, positive nitrogen balance is extremely difficult to achieve in hyper metabolic individuals, and so muscular tissue wasting is common.
Sports Science (1920 Until Present) Advances in conditioning and nutrition enabling drug-free performances unthinkable just a decade ago trace much of their origins to canine research. The use of dogs to measure metabolic alterations of exercise and nutrition dates back to the earliest days of modern exercise physiology. Scientific notables Drs. A.V. Hill, Dill and others helped build the foundation of modern-day exercise physiology with canine work. In numerous studies, dogs have been used to examine general exercise metabolism, and in more specific studies, lactic acid, amino acid and fat kinetics, among other metabolites.
Surprising to many, a significant number of today’s most efficacious and powerful sports nutrients and practices were first proven on dogs. Creatine-an important muscle energy nutrient abundant in wild diets but depleted in modern foods—is one example. Recent studies in humans show Creatine supplements increase physical performance, the rate of recovery after workouts and protein (muscle) synthesis to a significant degree.
However, it is not widely known that the first major study revealing the anabolic properties of Creatine resulted from canine research. In 1923, Dr. Benedict of Cornell reported his findings on healthy dogs given Creatine supplementation. They noted a sharp increase in nitrogen retention in dogs receiving a modest amount of Creatine. Creatine is naturally found in high amounts in wild prey species, but is found in very low amounts in commercial dog foods because of processing.
Similarly, the modern widespread use of lactose-reduced whey (lactalbumin) protein for medical foods, human athletes and infant formulas is based on dog studies. In the 1930s, investigators noted the very high biological value (BV) of whey proteins when predigested into small amino acid groups and given to dogs, which has also been found to be the case in human subjects.
Glucose polymers and medium-chain triglycerides, the predigested nutritional forms of carbohydrates and fats respectively, have been used successfully on dogs with metabolic advantages essentially identical to that noted in human subjects.
Important insights for optimally effective timing and use of sports supplements and foods has resulted from canine research. The beneficial use of carbohydrate supplementation during exercise has been repeatedly demonstrated in human studies. Carbohydrate supplements given during exercise delay fatigue, spare glycogen stores and help fight post-workout muscle breakdown. However, it is not widely known that the first study demonstrating these performance-enhancing benefits occurred via canine research.
In the 1930s, Dr. Dill used the famous "Joe" dog to determine if exogenous (extra) calorie sources in the form of carbohydrates could help support blood sugar and extend endurance capacity. Without extra carbohydrates, Joe was able to exercise about two hours to near exhaustion. But when provided carbohydrates in water every 30 minutes with a very brief break, Joe was able to exercise for 17 hours!
More recently, research on dogs has proved the timing of medical foods to be of extreme importance. Taking in high quality predigested medical foods after workouts—within 30 minutes-greatly increased the degree and rate of recovery in dogs after strenuous workouts lasting 150 minutes. The rate of protein synthesis (muscle repair and growth), generally depressed after exercise, was 30% greater in dogs taking in medical foods immediately after workouts. This study confirms earlier research on rats and human subjects.
Canine Research (1900 Until Present) The canine body has not fundamentally changed in a very long time. However, the understanding of the canine body is undergoing a modern revolution.
This major breakthrough in understanding stems from two main areas of investigation. First, a fresh recognition of the evolutionary food habits of dogs has contributed enormously. The second contribution comes from discovering the many parallels between human and canine exercise metabolism.
The common denominator to these seemingly unconnected discoveries is what scientists refer to as a "unifying theory". In other words, a new way of looking at old information that suddenly makes sense of it all--helps explain "why" things are. The unifying theory for dog nutrition is as old as dogs themselves. It comes from answering a single question:
What are Dogs Genetically Designed to Eat? In other words, through merciless "natural selection" over eons, what food preferences and traits have dogs evolved to enable their survival? This is not merely an academic question. Until the recent ascent of man destroyed habitats and natural food chains, wild dogs covered more of the world than any other land predator. Clearly, wolves and wild dogs are one of nature’s best-selling genetic designs for survival, and therefore discovering what and how they eat is important.
To understand this eating behavior, a brief review of the biological evolution that’s resulted in modern wild and domestic dogs is in order. Anthropologists generally agree that the ancient lineage of dogs can be traced back to a little creature called a Miacid. This small, meat-eating mammal is thought to be the precursor (ancestor) of cats, dogs, bears and related species. Miacids were highly carnivorous, a fact borne out by their teeth and skull remains. However, somewhere about 5 million years ago, dogs began to diverge from this family tree, becoming more generalized in feeding as evidenced by evolving dental features.
Tooth structure and features help experts determine how animals make their living and what they eat. For example, cats, which feature almost exclusively sharp tearing and puncturing teeth, can live their entire adult lives on meat and water meeting all their needs.
In contrast, dogs have much more generalized teeth; powerful and sharp in the front, broader and grinding in the back. Unlike cats, dogs can survive on almost anything, or almost nothing. Not just meat as with cats, but dogs can also supplement the diet with bugs, berries, roots, old road kills, whatever. Dogs can survive on food items that more specialized cats would not touch.
Dogs are carnivores. However, this catchall phrase is more often used to sell dog food than to provide clarity. Like cats, bears, hyenas and others, dogs belong to the order Carnivora. But there are degrees of carnivorous behavior, ranging from pure eaters like cats to much more opportunistic, omnivorous feeders like bears and dogs.
Grizzly and related Brown Bears are the largest land predators. These remarkably powerful animals can weigh up to ¾ of a ton, and have awesome teeth and jaws capable of quickly killing any animal in their world. Yet television wildlife specials reveal that for much of the year, these large animals forage on berries, roots and whatever food sources are available. Similarly, Russian scientists have reported that Polar Bears, which under ideal conditions will consume 200 pounds of seal per day, can resort to eating seaweed rather than starve when times are tough.
What Do Dogs Eat in the Wild? Equally important, how do they eat--in what order do they feast on the different body parts of prey species? And what do these food preferences mean to today’s dogs and medical foods? Ironically, the two groups with the most light to shed on what wild dogs eat--native people and wildlife biologists--have been ignored.
Native peoples throughout the world have lived around wild dogs for millennia. Their intimate knowledge of what and how wild dogs eat has been passed though their folklore for countless generations. Yet because they typically lived in relatively simple cultures, experts considered their observations tainted with mystic significance, and so generally disregarded their valuable insights.
Wildlife biologists are another group with in-depth knowledge of wild dog food habits that are also largely ignored. In general, observations from native peoples and wildlife biologists are in agreement regarding food habits of wolves and wild dogs.
This is What Dogs are Genetically Designed to Eat. If fortunate enough to make a large kill, wolves and wild dogs generally follow a stereotypic pattern of opening the lower body cavity, often before consuming internal organs or muscle meat.
From the stomach and upper intestines, they greedily extract the partially digested grasses and vegetable matter (digesta) eaten by the prey animal. Since prey species are generally herbivores that can be browsers or grazers, this digesta covers a wide range of grasses, sedges and other vegetable matter.
When they eat small prey such as mice, lemming or even larger fare like hares and rabbits, they "wolf" prey items down, generally whole. In this way, wolves and wild dogs also consume the stomach contents of the prey animal.
Seen through the lens of "evolutionary adaptation", the preference for digesta makes survival sense. Inside the intestine and plant matter is a wide array of nutrients including vitamin C, FOS and trace minerals, probiotics and enzymes.
Wolves and wild dogs obviously enjoy and benefit from eating meat. Nutrients in meat that promote canine survival and health include amino acids, Carnitine, Creatine, vitamins and minerals.
But clearly, wolves and wild dogs have evolved to seek and benefit from the consumption of non-meat dietary components derived from wild diets.
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