The Omnivorous Dog Part 2: Macro Nutrient Requirements Don’t Lie

Last time, I gave you a very generalized overview on the dog’s [very limited] ability to physically digest plant materials.

This time we’re going to look at the macro nutrient requirements of the omnivorous dog.

As you know, macro nutrients are those nutrients required in the greatest amounts: protein, fats and carbohydrates.

Proteins and fats can be obtained from plant and animal sources with plants containing only a fraction of these nutrients when compared to animal sources.

Carbohydrates can only be found in plants.  Absent human adulteration of foods, by slathering on sauces, breading and other such unhealthy additions, you will not find a single carb in body or bone tissue of animal source foods.



In the case of the omnivorous human, the carbohydrate requirement is 3-4 times the requirement for protein, with fat being the nutrient required in the least amount.  The primary energy source for the human is the carbohydrate, the nutrient required in the highest amount.  Good carbs come from unadulterated fruits, vegetables and whole grains – not breaded fried chicken or Cheetos.  It is possible for the human to meet all 3 macro nutrient requirements just by targeting the carbohydrate requirement as long as whole grains, legumes and/or nuts (higher end protein sources for plants) are included in the mix.  If the world were to suddenly lose all meat sources, the human would be just fine on a diet of plants alone.



The dog has no nutritional requirements for carbohydrates.   Protein and fat together make up 100% of the  macro nutrient requirements. Unfortunately, very little research has been done to determine just what the protein and fat requirements are [more on this at another time].   The primary energy source for the dog is fat, which means fat (animal source) should be the nutrient required in the highest amount, but refer back to the lack of research.  Just like the human can satisfy all his nutritional requirements from one type of food (plants), so too can the dog – eating other animals.   If all plants disappeared from the planet, the dog would do just fine on a diet of other animals alone.  Remove all meats from the world (as well as all manufactured supplements used in vegetarian and vegan dog food diets), and the dog would die.  End of story.




That the ‘omnivorous’ dog physiologically tends highly carnivore, due to his digestive abilities and nutrient requirements, has been known since the dog was first used as a laboratory animal.  The earliest published scientific paper I have been able to find stating this was written by G. R. Cowgil in 1928.  The pet food industry, AAFCO, the NRC, all serious text books and reference material provided to hopeful vet school students … none deny that carbohydrates are not required by the dog.  It is also agreed that the most efficient source of all required nutrients is animal tissue.

Despite the facts agreed to by all, commercial dog foods continue to contain more carbohydrates than protein and fat combined.   Here’s how to calculate the carbohydrate content of your dog food:  From the Guaranteed Analysis, add the protein and fat content together, then subtract that number from 100.  The result will be the carbohydrate content. [This only works on kibble.  Canned foods use a different method.]  Go ahead and do the calculation, I’ll wait!

OK, so you’ve calculated the carbohydrate content of your dog’s food.  Is it more than the combined content of protein and fat?  

Knowing what you now know; that the dog’s ability to digest plant materials is extremely limited and that the dog has no nutritional requirement for anything plants – remember, this includes fruits and vegetables – have to offer, how does this make you feel about what you’re feeding your dog?

Next time I’ll show you how this all slipped by you in the past.  It isn’t that your research was faulty, it’s that you were asking the wrong questions.   I’ll show you where to look and what questions to ask.  



Until then, here’s your homework:  Familiarize yourself with Nutritional Requirements of Dogs and Cats (NRC 2006).  This book is the impartial cliff notes of all available research, at least up until publication.  It can be purchased on Amazon, which I highly recommend,  but most pages are available free on Google Here.  If, as I think you may, you go right to the Carbohydrate section, pay very close attention to what is NOT said.  I’ll give you a hint:  The same deficiency, pun intended, is not found in the sections on protein and fat. 






Preliminary Evaluation of The Barkista’s Beef and Turkey Muttloaves

The Guaranteed Analysis, as well as all minerals except Selenium and Iodine came back today.

On paper, using the measures of the ingredients, the analyses should be:

Beef Muttloaf                                                                            Turkey Muttloaf

Protein 51%                                                                               51%

Fat          21%                                                                               21%

Carb       28%                                                                              28%

Yup, they both should have come out the same.  In both cases, 83% of protein is provided from animal sources.  

Now let’s see what the lab said:

Dry Matter analysis =

Protein 38.72%

Fat          24.04%

Carb       32.26%


Dry Matter Analysis =

Protein 37.47%

Fat          19.96%

Carb       39.02%


I’m a little confused on several levels.

Since the loaves are mixed by hand, I would expect variance throughout the sample, but since a relatively significant sized sample was used for testing,  the variance extremes should have been reduced.  A 4% variance from prediction on any of the 3…  I wouldn’t have been concerned.

In the case of the beef, while cringing at the 4.26% higher than predicted carb content, I’m not even blinking at the 3.04% higher than predicted fat.  The 12.28% lower than predicted protein causes me serious pause.

The turkey is even more perplexing.   Again, fat is a non issue here, in this case showing as 1.04% lower than predicted.  I am confused over the 13.53% lower than predicted protein.  I am absolutely mystified over the 11.02% higher than predicted carb content because…  the amount of binder used, the rolled oats, was exactly the same as was used in the beef; 7 ounces measured on a fully calibrated digital scale.

This particular lab was only looking at Guaranteed Analyses and mineral content (excluding Iodine) [I have not run the calculations to evaluate mineral content yet].    The Turkey Muttloaf, from the exact same batch, was sent to another lab for more extensive testing, the results of which still are not in.  Among those items being tested are Amino Acid and Fat profiles, which will look more in depth at the protein and fat content of the sample.

If the profiles provided by the second lab shows closer to predicted (I never expected it to be spot on) contents, I think it safe to assume the lab performing the Guaranteed Analyses was in error.

If, on the other hand, the further analysis also shows significant variances from predicted, then

a) the raw ingredients used in the products sent to the labs were not mixed as thoroughly as I thought they were.

– this could explain the significant carb difference between the 2 samples when the identical measure of oats was used in both.

b) the labels on human grade foods are as misleading as labels on dog foods!

– if the label claims a certain percentage of protein, fat and carbs, but the analysis doesn’t back up the claim…need I say more?

Either way, even with the current, very disappointing (protein and carbs, specifically) Guaranteed Analysis, the Beef and Turkey Muttloaves still may be determined to be a food rather than a treat.  Final determination will be made after I get the mineral content calculations done, and I receive the report from the second lab.

There will be  many, many more discussions surrounding The Barkista’s Muttloaves.  Whether or not you are a Barkista customer, stay tuned as these discussions will help to teach you how to read between the lines of labels and learn what questions to ask the manufacturers of your dog foods and treats.

Incidentally…  are the manufacturers of your dog’s food and treats as transparent as The Barkista?