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Stealth, thanks for the references. However, my problem with that book is that it already *Assumes* dogs are omnivores, and doesn't really look critically at it
ratio of GI tract length to total body length is 6:1 for dogs, 4:1 for cats, 10:1 for rabbits, and 20:1 for some herbivores
Wouldn't this data point towards a heavy carnivore sway?
"True carnivores are limited to what is available from prey tissues such as skeletal muscle and liver to provide energy and nutrients, including protein, taurine, arginine, arachidonic acid, and niacin. Consequently, carnivorous animals developed more efficient pathways to use these nutrients, and have lost the ability to synthesize them from precursors. Being omnivorous and receiving a varied diet of plant and animal tissue, dogs maintained or improved the ability to synthesize nutrients from precursors."
Do they provide any data that proves this improved ability?
dogs digest starch efficiently via pancreatic enzymes and salivary enzymes (amylase)
Digest? Okay I can believe that, if they are pushed to it by being fed grains in the first place. But absorb? Hmmm.
Here are a few other sources...
Dogs and cats have the internal anatomy and physiology of a carnivore ( 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.) 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.
And re: amylase
"Dogs do not normally produce the necessary enzymes in their saliva (amylase, for example) to start the break-down process of carbohydrates and starches; amylase in saliva is something omnivorous and herbivorous animals possess, but not carnivorous animals. This places the burden entirely on the pancreas, forcing it to produce large amounts of amylase to deal with the starch, cellulose, and carbohydrates in plant matter. The carnivore's pancreas does not secrete cellulase to split the cellulose into glucose molecules, nor have dogs become efficient at digesting and assimilating and utilizing plant material as a source of high quality protein. Herbivores do those sorts of things"
Canine and Feline Nutrition Case, Carey and Hirakawa Published by Mosby, 1995
ratio of GI tract length to total body length is 6:1 for dogs, 4:1 for cats, 10:1 for rabbits, and 20:1 for some herbivores
Wouldn't this data point towards a heavy carnivore sway?
"True carnivores are limited to what is available from prey tissues such as skeletal muscle and liver to provide energy and nutrients, including protein, taurine, arginine, arachidonic acid, and niacin. Consequently, carnivorous animals developed more efficient pathways to use these nutrients, and have lost the ability to synthesize them from precursors. Being omnivorous and receiving a varied diet of plant and animal tissue, dogs maintained or improved the ability to synthesize nutrients from precursors."
Do they provide any data that proves this improved ability?
dogs digest starch efficiently via pancreatic enzymes and salivary enzymes (amylase)
Digest? Okay I can believe that, if they are pushed to it by being fed grains in the first place. But absorb? Hmmm.
Here are a few other sources...
Dogs and cats have the internal anatomy and physiology of a carnivore ( 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.) 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.
And re: amylase
"Dogs do not normally produce the necessary enzymes in their saliva (amylase, for example) to start the break-down process of carbohydrates and starches; amylase in saliva is something omnivorous and herbivorous animals possess, but not carnivorous animals. This places the burden entirely on the pancreas, forcing it to produce large amounts of amylase to deal with the starch, cellulose, and carbohydrates in plant matter. The carnivore's pancreas does not secrete cellulase to split the cellulose into glucose molecules, nor have dogs become efficient at digesting and assimilating and utilizing plant material as a source of high quality protein. Herbivores do those sorts of things"
Canine and Feline Nutrition Case, Carey and Hirakawa Published by Mosby, 1995