The Canine Digestive System

The Digestive System of a Dog


The following article was contributed by Robert McDowell, a Medical Herbalist from Australia and owner of Herbal Treatments


The Digestive System of a Dog is Different:

Dogs are primarily carnivores not herbivores like horses or cows. They have a much shorter and faster digestive tract and they don’t usually eat weeds.

How can we assume that they will respond to herbal medicines in the same way as say Horses, or even Humans?

The answer, I believe, is to be found in observing the environment, the dog’s place in it and its interaction with it. After all, this is where we find the answers to almost all of our other dilemmas, so why not this one.

The dog is a scavenger and hunter.

The herbivore has a long slow Gastro Intestinal Tract (G.I.T.) designed to extract nutrients from a large bulk of difficult to process plant material. The cow even has several stages of chewing in its chemical factory. A dog on the other hand, has a short and fast digestive system designed to quickly extract nutrients from flesh and other animal products.

The herbivore spends most of its time grazing, protecting itself with its bulk and its herding instincts. The carnivore spends only a small proportion of its time eating. It is designed to be able to go for long periods without food and it must be able to be on the move all the time.

Dogs of course do live off herbs and plants in the final analysis. It is just that most often some other animal has digested them first. We do see dogs favoring the partly digested stomach contents of their prey and in the wild this would be their primary source of plants and grains. We do occasionally see a dog eating fresh plant material but this is usually for a very specific purpose and in response to an instinctive need to treat an immediate health problem.

A herbivore depends on a digestive system, which is very stable. The animal chooses almost every mouthful, with a view to maintaining stability within the chemical factory, which is its gut.

All its instincts are tuned to this task. The changes, which occur in the feed available, are slow changes. The available feed varies week by week with the passage of the seasons and the weather so the gut is able to adapt slowly to these changes.

The carnivore on the other hand eats irregularly and mostly has very little choice. It eats whatever it can get.

This can be the fresh raw flesh or stomach contents of a warm-blooded animal, a rotting carcass or long dead bones, the feces of another animal or at a pinch, fallen fruit or nuts, insects or whatever else it comes across.

Dogs, (and humans) can gulp their food.

One facility of the dog’s digestive system is that it can gulp a large amount of food quickly due to danger or to competition.

However, for ideal health and whenever circumstances permit, it shouldn’t. We all know a dog would rather spend a whole afternoon under a bush somewhere, salivating and chewing on a bone or a bit of dried up meat and skin. (Not the sort of thing you want happening on your living room carpet.)

The dog puts into its gut whatever it can, and then adapts its digestion to make the best of it.

For most of the time the stomach of a dog should be empty, waiting to see what will be next on the menu.

Dogs don’t have digestive complaints.

Of course they do seem to have digestive system problems at times, but this is only in domestic dogs, whose diet has been hugely subverted by us humans.

As a herbalist I don’t find myself using all those herbs which I routinely use for digestion problems in both humans and horses. I never need to prescribe Chamomile or Slippery Elm for stomach ulcers or colic. I am not prescribing Liquorice, Senna, Fennel, Dandelion, Alfalfa, Aloes or Blue Flag for indigestion constipation or diarrhea.

Everything happens so quickly in the dog’s gut, that unless they are poisoned and the whole metabolism is thrown into turmoil, digestion of the last meal is all over and done with and the stomach is empty and waiting.

Most dogs health problems are dietary.

Just about all the conditions I routinely treat domestic dogs for are derived from the effects of over eating, poor diet, inappropriate exercise, stress and confinement.

In the case of racing and show dogs, we can add supplement abuse to this list.

This abuse of the frequency, variability and quality of feed does produce severe health problems in dogs from premature arthritic problems in their youth, skin and obesity in middle age, and an increasing variety of cancers which are rare in other animal species and probably almost unknown in the wild.

When treating a dog I always first have to consider the effects of their diet. If their diet has not been one based on raw meat and bones, if it has not had the benefit of variability, irregularity and ripened (you may say ‘rotten’) treats, you first need to sort out the diet.

The two most common effects of our dogs diet and lifestyle are blood toxicity and minerals balance problems. It is these two basic areas from which most of the health problems I treat are derived.

Blood Cleansers.

The results of denying the dog its natural rhythm of eating and its natural variety of input can be seen primarily as blood toxicity. The dogs metabolism functions by absorbing nutrients as fast as it can into the system and then spending the fasting times, when there is nothing in the gut, utilizing and rationalizing all these nutrients and clearing toxins from the system.

With regular and rather complex meals, little variety, little exercise and no fasting at all, the dogs system becomes toxic and most of my canine herbal treatments are heavily dependent on a class of herbs called alternatives.

Alterative’s are blood cleansers and are usually high in Iron or Sulfur and they are tonic in their affect. They assist the primary systems in the body to dispose of waste products. This is to say they stimulate the blood quality through the Liver, the Lymph and the Kidneys.

The most common the these which find their way into my treatments are Garlic, Liquorice, Rosehips, Dandelion, Echinacea, Red Clover, Violet Leaves, Parsley, Yarrow, Nettle, Fennugreek and Horsetail.

The main illnesses which I believe to directly result from blood toxcicity problems are skin problems and cancers involving the lymphatic system (Lymphomas). My standard preventative and curative treatments, which involve some of the blood cleansing herbs above are:

  • Skin Problems/ Blood Cleanser
  • Blood Poisoning (Skin Sores & Hot Spots)
  • Lymphoma Cancer Support

However, since most dog’s problems come from our own lack of common sense and our own bad practices, we must first consider these, before setting out to treat our dog.

Do your dog a favor.

If your dog’s health is not as good as it should be, first change its diet and feed it once only a day with raw meaty bones and with cooked up grains, vegetables and greens. In addition fast your dog a couple of days each week. Give it no commercial dog food at all and keep this program up for a month.

At the end of this month on the new diet, look at the dog’s coat and its eye, look at its vitality and ask yourself how it is feeling. If you have to admit that it looks and feels great, you can be sure you have made a big step toward better health and life quality.

If some health problems still persist you should then consider professional help from a vet or herbalist to identify and correct the underlying factors responsible for these problems.

Robert McDowell Herbalist Nov 1st, 2001

Robert McDowell has been treating animal problems for the last 12 years and is an experienced authority in the support and treatment of these conditions and the side effects of modern Chemotherapy and Radiotherapy treatments (he and his treatments helped in an 18-month remission in our female Golden Retriever.  Robert also offers health consultations online.  Please go to his website at  Read about Robert and his treatment programs and the testimonials about those treatments.  Remember also that such treatments are equally effect for humans.