Kirkland Signature Nature’s Domain Dog Food earns the Advisor’s mid-tier rating of 3.5 stars.
The Kirkland Signature Nature’s Domain product line includes three dry dog foods, each claimed to meet AAFCO nutrient profiles for all life stages.
The following is a list of recipes available at the time of this review.
- Nature’s Domain Turkey Meal and Sweet Potato
- Nature’s Domain Salmon Meal and Sweet Potato
- Nature’s Domain Beef Meal and Sweet Potato (3 stars)
Nature’s Domain Turkey Meal and Sweet Potato was selected to represent the other products in the line for this review.
Kirkland Signature Nature's Domain Grain Free Turkey Meal and Sweet Potato
Dry Dog Food
Estimated Dry Matter Nutrient Content
Ingredients: Turkey meal, sweet potatoes, peas, potatoes, canola oil, potato protein, potato fiber, natural flavor, flaxseed, ocean fish meal, salt, choline chloride, dried chicory root, tomatoes, blueberries, raspberries, Yucca schidigera extract, dried Enterococcus faecium fermentation product, dried Lactobacillus acidophilus fermentation product, dried Lactobacillus casei fermentation product, dried Lactobacillus plantarum fermentation product, dried Trichoderma longibrachiatum fermentation extract, vitamin E supplement, iron proteinate, zinc proteinate, copper proteinate, ferrous sulfate, zinc sulfate, copper sulfate, potassium iodide, thiamine mononitrate (vitamin B1), manganese proteinate, manganous oxide, ascorbic acid, vitamin A supplement, biotin, niacin, calcium pantothenate, manganese sulfate, sodium selenite, pyridoxine hydrochloride (vitamin B6), vitamin B12 supplement, riboflavin (vitamin B2), vitamin D supplement, folic acid
Fiber (estimated dry matter content) = 3.3%
Red items when present indicate controversial ingredients
|Estimated Nutrient Content|
|Dry Matter Basis||27%||16%||50%|
|Calorie Weighted Basis||23%||33%||44%|
The first ingredient in this dog food is turkey meal. Turkey meal is considered a meat concentrate and contains nearly 300% more protein than fresh turkey.
The second ingredient includes sweet potato. Sweet potatoes are a gluten-free source of complex carbohydrates in a dog food. They are naturally rich in dietary fiber and beta carotene.
The third ingredient includes 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.
The fourth 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 fifth ingredient is canola oil. Many applaud canola for its favorable omega-3 content while some condemn it as an unhealthy fat.
Much of the objection regarding canola oil appears to be related to the use of genetically modified rapeseed as its source material.
Yet others find the negative stories about canola oil more the stuff of urban legend than actual science.1
In any case, plant-based oils like canola are less biologically available to a dog than fish oil as a source of quality omega-3 fats.
The sixth ingredient is potato protein, the dry residue remaining after removing the starchy part of a potato.
Even though it contains over 80% protein, this ingredient would be expected to have a lower biological value than meat.
And less costly plant-based products like this can notably boost the total protein reported on the label — a factor that must be considered when judging the actual meat content of this dog food.
The seventh ingredient is potato fiber, a source of dietary fiber. Fiber in reasonable amounts can help stabilize blood sugar levels and reduce a dog food’s caloric content.
After the natural flavor, we find flaxseed, 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.
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 three notable exceptions…
First, we note the use of an ingredient listed as ocean 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.2
Unfortunately, this particular item is anonymous. Because various fish contain different types of fats, we would have preferred to have known the source species.
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 also 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.
Kirkland Signature Nature’s Domain Dog Food
The Bottom Line
Judging by its ingredients alone, Nature’s Domain Dog Food looks like an average dry kibble.
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 27% and a mean fat level of 16%. Together, these figures suggest a carbohydrate content of 50% for the overall product line.
And a fat-to-protein ratio of about 58%.
Near-average protein. Near-average fat. And near-average carbs when compared to a typical dry dog food.
However, when you consider the protein-boosting effect of the peas, potato protein, flaxseed (or pea protein and garbanzo beans found in some of the other recipes), this looks like the profile of a kibble containing a below-average amount of meat.
Kirkland Signature Nature’s Domain is a grain-free plant-based kibble using a below-average amount of meat or fish meals as its main sources of animal protein, thus earning the brand 3.5 stars.
Note: Although this recipe does not appear to have changed, we have lowered its rating due to the greater weight we now place on the use of plant-based meat protein substitutes.
Please note certain recipes are sometimes given a higher or lower rating based upon our estimate of their total meat content.
Rice ingredients can sometimes contain arsenic. Until the US FDA establishes safe upper levels for arsenic content, pet owners may wish to limit the total amount of rice fed in a dog's daily diet.
A Final Word
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Notes and Updates
07/06/2013 Last Update