Costco Kirkland Signature Dog Food receives the Advisor’s second-highest tier rating of 4 stars.
The Kirkland Signature product line includes 6 dry dog foods.
Each recipe below includes its related AAFCO nutrient profile when available on the product’s official webpage: Growth, Maintenance, All Life Stages, Supplemental or Unspecified.
Important: Because many websites do not reliably specify which Growth or All Life Stages recipes are safe for large breed puppies, we do not include that data in this report. Be sure to check actual packaging for that information.
- Costco Kirkland Signature Adult Chicken [M]
- Costco Kirkland Signature Puppy (4.5 stars) [A]
- Costco Kirkland Signature Small Dog (4.5 stars) [M]
- Costco Kirkland Signature Adult Lamb (3.5 stars) [M]
- Costco Kirkland Signature Mature Dog (4.5 stars) [M]
- Costco Kirkland Signature Healthy Weight (3 stars) [M]
Costco Kirkland Signature Adult Chicken recipe was selected to represent the other products in the line for this review.
Kirkland Signature Adult Chicken
Dry Dog Food
Estimated Dry Matter Nutrient Content
Ingredients: Chicken, chicken meal, whole grain brown rice, cracked pearled barley, chicken fat (preserved with mixed tocopherols), egg product, dried beet pulp, potatoes, fish meal, flaxseed, natural flavor, brewers dried yeast, millet, potassium chloride, salt, choline chloride, carrots, peas, dried kelp, apples, cranberries, rosemary extract, parsley flake, dried chicory root, glucosamine hydrochloride, dried Lactobacillus acidophilus fermentation product, dried Bifidobacterium animalis fermentation product, dried Lactobacillus reuteri fermentation product, vitamin E supplement, iron proteinate, zinc proteinate, copper proteinate, ferrous sulfate, zinc sulfate, copper sulfate, potassium iodide, thiamine mononitrate, manganese proteinate, manganous oxide, chondroitin sulfate, ascorbic acid, vitamin A supplement, biotin, niacin, calcium pantothenate, manganese sulfate, sodium selenite, pyridoxine hydrochloride (vitamin B6), vitamin B12 supplement, riboflavin, vitamin D supplement, folic acid
Fiber (estimated dry matter content) = 4.4%
Red denotes controversial item
|Estimated Nutrient Content|
|Dry Matter Basis||29%||18%||45%|
|Calorie Weighted Basis||25%||37%||39%|
The first ingredient in this dog food is chicken. Although it is a quality item, raw chicken contains up to 73% water. After cooking, most of that moisture is lost, reducing the meat content to just a fraction of its original weight.
After processing, this item would probably account for a smaller part of the total content of the finished product.
The second ingredient is chicken meal. Chicken meal is considered a meat concentrate and contains nearly 300% more protein than fresh chicken.
The third ingredient is brown rice, a complex carbohydrate that (once cooked) can be fairly easy to digest. However, aside from its natural energy content, rice is of only modest nutritional value to a dog.
The fourth ingredient is barley. Barley is a starchy carbohydrate supplying fiber and other healthy nutrients. However, aside from its energy content, this cereal grain is of only modest nutritional value to a dog.
The fifth ingredient is chicken fat. Chicken fat is obtained from rendering chicken, a process similar to making soup in which the fat itself is skimmed from the surface of the liquid.
Chicken fat is high in linoleic acid, an omega-6 fatty acid essential for life. Although it doesn’t sound very appetizing, chicken fat is actually a quality ingredient.
The sixth ingredient is egg product, an unspecified (wet or dry?) form of shell-free eggs. Quality can vary significantly. Lower grade egg product can even come from commercial hatcheries — from eggs that have failed to hatch.
In any case, eggs are easy to digest and have an exceptionally high biological value.
The seventh ingredient is beet pulp. Beet pulp is a controversial ingredient, a high fiber by-product of sugar beet processing.
Some denounce beet pulp as an inexpensive filler while others cite its outstanding intestinal health and blood sugar benefits.
We only call your attention here to the controversy and believe the inclusion of beet pulp in reasonable amounts in most dog foods is entirely acceptable.
The eighth ingredient is potato. Potatoes can be considered a gluten-free source of digestible carbohydrates. Yet with the exception of perhaps their caloric content, potatoes are of only modest nutritional value to a dog.
The ninth ingredient is fish meal, another protein-rich meat concentrate.
Fish meal is typically obtained from the “clean, dried, ground tissue of undecomposed whole fish and fish cuttings” of commercial fish operations.1
Unfortunately, this particular item is anonymous. Because various fish contain different types of fats, we would have preferred to have known the source species.
From here, the list goes on to include a number of other items.
But to be realistic, ingredients located this far down the list (other than nutritional supplements) are not likely to affect the overall rating of this product.
With five notable exceptions…
First, flaxseed is one of the best plant sources of healthy omega-3 fatty acids. Provided they’ve first been ground into a meal, flax seeds are also rich in soluble fiber.
However, flaxseed contains about 19% protein, a factor that must be considered when judging the actual meat content of this dog food.
Next, brewers yeast can be a controversial item. Although it’s a by-product of the beer making process, this ingredient is rich in minerals and other healthy nutrients.
Fans believe yeast repels fleas and supports the immune system.
Critics argue yeast ingredients can be linked to allergies. This may be true, but (like all allergies) only if your particular dog is allergic to the yeast itself.
In addition, a vocal minority insists yeast can increase the risk of developing the life-threatening condition known as bloat. However, this is a claim we’ve not been able to scientifically verify.
In any case, unless your dog is specifically allergic to it, yeast can still be considered a nutritious additive.
What’s more noteworthy here is that brewers yeast contains about 48% protein, a factor that must be considered when judging the actual meat content of this dog food.
In addition, we find peas. Peas are a quality source of carbohydrates. And like all legumes, they’re rich in natural fiber.
However, peas contain about 25% protein, a factor that must be considered when judging the meat content of this dog food.
Next, chicory root is rich in inulin, a starch-like compound made up of repeating units of carbohydrates and found in certain roots and tubers.
Not only is inulin a natural source of soluble dietary fiber, it’s also a prebiotic used to promote the growth of healthy bacteria in a dog’s digestive tract.
And lastly, this food contains chelated minerals, minerals that have been chemically attached to protein. This makes them easier to absorb. Chelated minerals are usually found in better dog foods.
Costco Dog Food Review
Judging by its ingredients alone, Kirkland Signature Dog Food looks like an above-average dry product.
But ingredient quality by itself cannot tell the whole story. We still need to estimate the product’s meat content before determining a final rating.
As a group, the brand features an average protein content of 28% and a mean fat level of 15%. Together, these figures suggest a carbohydrate content of 49% for the overall product line.
And a fat-to-protein ratio of about 54%.
Near-average protein. Near-average fat. And near-average carbs when compared to a typical dry dog food.
Even when you consider the mild protein-boosting effect of the flaxseed, peas and brewers yeast, this looks like the profile of a kibble containing a moderate amount of meat.
Costco’s Kirkland Signature is a plant-based dry dog food using a moderate amount of named meat meals as its main sources of animal protein, thus earning the brand 4 stars.
Please note certain recipes are sometimes given a higher or lower rating based upon our estimate of their total meat content and (when appropriate) their fat-to-protein ratios.
Those looking for a lite kibble from the same company may wish to visit our review of Kirkland Healthy Weight Formula dog food.
Kirkland Dog Food
The following list (if present) includes all dog food recalls since 2009 directly related to this product line. If there are no recalls listed in this section, we have not yet reported any events.
- Kirkland Dog Food Recall (5/5/2012)
Readers interested in Costco Kirkland dry dog food may also wish to check out these popular pages, too…
Important FDA Alert
The FDA has announced it is investigating a potential connection between grain-free recipes and dilated cardiomyopathy. Click here for details.
A Final Word
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Notes and Updates
07/16/2018 Last Update
- Association of American Feed Control Officials ↩