Kirkland Signature dog food is a well-known and loved brand. It’s owned and sold by Costco.
The brand has two product lines: Kirkland Signature Super-Premium and Kirkland Signature Nature’s Domain dog foods.
The range, on the whole, won dog owners’ hearts by offering better-than-average ingredients at an affordable price.
This struck a chord with anyone trying to balance the price and quality.
However, affordability always includes some compromise. And Kirkland Nature’s Domain is no exception.
In this Kirkland Nature’s Domain dog food review, we will look at the nutritional profile, online reviews, and alternatives to one of the formulas in this product line.
Ready? Let’s go!
Nature’s Domain Dog Food Overview
Kirkland Signature Nature’s Domain is an affordable brand line of grain-free dog food.
Diamond Pet Foods produce this dog food on behalf of Costco.
All the products in Nature’s Domain dog food line are grain-free formulas. There are 5 dry foods and 2 canned dog foods.
The recipes within Kirkland Signature Nature’s Domain include:
- Kirkland Signature Nature’s Domain Salmon Meal & Sweet Potato Dry Food
- Kirkland Signature Nature’s Domain Turkey Meal & Sweet Potato Dry Food
- Kirkland Signature Nature’s Domain Beef Meal & Sweet Potato Dry Food
- Kirkland Signature Nature’s Domain Organic Chicken & Pea Dry Food
- Kirkland Signature Nature’s Domain Puppy Chicken & Pea Dry Food
- Kirkland Signature Nature’s Domain Organic Chicken with Vegetables Canned Food
- Kirkland Signature Nature’s Domain Turkey & Pea Stew Canned Food
In this Nature’s Domain dog food review, we will take a closer look at Salmon Meal & Sweet Potato recipe.
Recipe and Label Analysis
Below you can see the ingredients and the guaranteed analysis of Kirkland Nature’s Domain Salmon Meal & Sweet Potato recipe. Other formulas are pretty similar to this recipe.
Kirkland Signature Nature’s Domain Salmon Meal & Sweet Potato Dog Food
Ingredient List: Salmon Meal, Sweet Potatoes, Peas, Potatoes, Canola Oil, Ocean Fish Meal, Pea Protein, Potato Fibre, Natural Flavour, Flaxseed, Salt, Choline Chloride, Dried Chicory Root, Tomatoes, Blueberries, Raspberries, Yucca Schidigera Extract, 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 (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.
* Bold denotes controversial items
Guaranteed Analysis
- Crude Protein 24% Minimum
- Crude Fat 14% Minimum
- Crude Fiber 3% Maximum
- Moisture 10% Maximum
- Calories: 3,590 kcals/kg (336 kcals/cup)
Ingredient Analysis
The first ingredient is a salmon meal. Salmon is good for your dog — besides a high-quality protein, it will also provide Omega-3 fatty acids.
But, meat meals are somewhat controversial. They can be either great sources of protein — or pretty bad.
How do you know which one it is? Usually, when the meat is specified, the protein is probably good. However, if you see an unspecified “meat and bone meal” or “meat by-products,” this might point to low-quality dog food.
In Nature’s Domain case, the meat, i.e. salmon, is specified. So that means we know exactly what we’re dealing with.
The second ingredient are sweet potatoes. They are complex carbohydrates and common in grain-free formulas.
Sweet potato formula is good for dogs. It is a good source of stable energy. Furthermore, sweet potato also contains dietary fiber. This improves digestion and absorption of nutrients.
The next ingredient are peas. Peas are also widespread in grain-free recipes. They have a high fiber content and even carry a certain amount of protein.
There are two potential problems with peas.
First, since they have protein, they will raise the overall protein in the formula. In other words, even though the label states 24% crude protein for this recipe, the total animal protein is probably lower because of peas.
The second problem is a little more insidious.
Peas, rice, and lentils can be split into several components within the ingredients list. This process is called “ingredients-splitting.” It pushes other ingredients to the forefront.
So, let’s say a brand uses a lot of peas in its formulas. If they want meat as the first ingredient, they just have to break down peas into pea flour, peas, pea starch, and other components. The more components, the smaller the individual amounts. And further down the ingredient list they go.
We know — it’s not what we would want to see in the ingredients list, either. But this practice is allowed.
Peas are followed by regular potatoes. They are ok for dogs, although the sweet potato is more nutritious. The regular ones here are probably used as filler.
The fifth ingredient is somewhat debated canola oil. Canola oil does have Omega-3 and Omega-6 fatty acids, which are beneficial to dogs. Omega fatty acids contribute to heart health, shiny fur, and healthy skin.
However, canola oil often comes from GMO crops. So if you are looking for more natural dog food, you might want to skip this one.
Furthermore, canola oil quickly turns rancid if left out in the open. Rancidity will destroy the healthy omega fatty acids ratio and turn them into unhealthy fats. Feeding your dog regularly with that kind of fat is dangerous.
The next ingredient in Nature’s Domain recipe is an ocean fish meal. The fish meal itself can be beneficial as a protein source and because it contains healthy Omega-3 fatty acids.
But we don’t like the generic name of this fish meal. Dog food brands use cheaper ingredients under general terms like “meat meal,” “poultry fat,” or “ocean fish.”
“Ocean fish” could refer to the menhaden fish, which is extremely healthy because it is less exposed to mercury. Or it could be some other type of fish with a much worse nutritional profile.
Though rare, mercury poisoning in dogs can be fatal.
The next ingredient, pea protein, is a pea derivative. Put simply; these are dried peas.
We are not particularly happy about this ingredient because it seems that there has been ingredient splitting in the formula. Meaning, the absolute quantity of peas in Nature’s Domain was split into two components.
The thing with pea protein is that it contains 55% protein. Isn’t that good? Nope. It’s harder for your dog to digest it, AND it does not contain all the amino acids your dog needs.
It does serve one purpose — to raise the overall protein. So, it’s a cheap protein-filler (if there is such a word). Think about it — what costs more? Peas or salmon? Exactly.
The next ingredient — potato fiber — contributes to the suspicion of ingredient splitting. Dietary fiber itself is good and beneficial for your dog’s digestive system.
But the ingredients splitting means that the ingredients list probably should have looked a little different.
The ninth ingredient is a generic natural flavor. Natural flavor can mean a lot of things (FDA). It is essential to specify precisely which compound we are talking about. That way, we can establish how nutritious it is (or isn’t).
The tenth ingredient is flaxseed. Flaxseeds are a common ingredient in dog food recipes and a valuable source of Omega-3 fatty acids. We’re glad to see them here. True, they are not as expensive, but they are beneficial to a dog’s health.
The formula also contains sodium selenite, which is a controversial ingredient. It provides selenium, which is essential for healthy cells in animals. However, too much of it can be toxic.
Truth be told, many vitamins and minerals are toxic in excessive amounts. Dog owners are worried about this mineral because the border between a healthy and a toxic dose is somewhat closer than with other elements.
Other Notable Ingredients
Nature’s Domain dog food contains a few exciting and high-quality ingredients further down the list worth mentioning.
Let’s look at the ingredients for a healthy digestive system first.
Higher up on the Nature’s Domain ingredient list, we can see that the formula contains dried chicory root. Costco’s website mentions that this ingredient is sourced from Belgium because it is rare.
Chicory root is rich in inulin. Inulin introduces healthy bacteria to your dog’s gut and makes it run more smoothly. The dog can then absorb other nutrients faster and more efficiently.
The formula also contains canine probiotics. These live cultures are slowly making their way into dog food products because they are essential to the healthy gut microbiome.
Finally, Nature’s Domain dog food also has a Yucca Schidigera extract. The extract comes from a dried plant root, and it neutralizes the odor of dogs’ feces. So, you might argue it’s a good thing.
In addition to digestive health, the formula includes many vitamins and chelated minerals.
This recipe has vitamin A, vitamin D, and vitamin E supplements. The formula also features many B-vitamins: B6, Vitamin B12 Supplement, riboflavin (vitamin B2), and folic acid.
Minerals are chelated, which is great for dog food. Basically, chelation means that a mineral is attached to a protein. This way, dogs can more easily absorb it and use it.
Finally, we should mention the ingredient missing in Nature’s Domain. Since this is a grain-free formula, there is some concern about dilated cardiomyopathy.
The 2019 FDA report stated that many dogs on grain-free diets experienced DCM due to decreased taurine levels. Most grain-free recipes nowadays add taurine to address this problem.
This formula, and the others in Kirkland grain-free recipes, do not contain taurine. In some cases, this won’t be a problem — but every dog is unique. We recommend you discuss it with your vet before feeding them to your dog.
Nutritional Analysis
Nature’s Domain Salmon Meal and Sweet Potato formula has 24% crude protein. The percentage is well above the AAFCO guidelines (18% minimum for most dogs). This means that your dog should get the complete amino acids and proteins for daily activities.
Yet, remember that most of the protein comes from a salmon meal? Meat meals are better protein sources than meat by-products, but whole meats are generally preferred.
Most Nature’s Domain dog food recipes use meals as the primary protein sources. Nature’s Domain Organic Chicken and Puppy formulas are exceptions, with whole meats as the first ingredients.
Furthermore, since there are plenty of peas in Nature’s Domain Salmon Meal & Sweet Potato dog food, some protein will come from vegetable sources.
It’s worth reiterating that vegetable protein is inferior to animal one and harder to digest.
What does all this mean? Considering that many of the Nature’s Domain dog food formulas use loads of peas, we are leaning towards those with whole meats as the first ingredient. For example, Nature’s Domain Organic Chicken recipe.
The Salmon Meal & Sweet Potato recipe also contains 14% crude fat. This amount is within the healthy range prescribed by AAFCO (10-20%).
The fat in this dog food comes mainly from canola oil, salmon meal, fish meal, and flaxseed to a minor extent.
It seems that there will be plenty of Omega-3s in this particular dog food, based on the sources. However, do not leave the dog food out in the open. There is a chance it will turn rancid because of canola oil.
The Nature’s Domain nutrient profile also mentions 3% crude fiber. This is within the AAFCO guidelines (<5%), but generally considered low.
The amount of fiber should contribute to healthy digestion in dogs, especially when combined with chicory root and probiotics.
Fiber mainly comes from sweet potatoes and peas in this recipe. But, going back to ingredients-splitting — the total quantity of peas is probably higher than what you might suspect at first glance.
So, if your dog is sensitive to legumes, you should keep an eye out for any digestive distress.
The last thing we should discuss here are calcium and phosphorus. These are not featured in the guaranteed analysis of the formula, but they are available on the Costco website.
Both Kirkland Super-Premium and Nature’s Domain dog foods tend to have a little too much of one or both in their formulas.
According to the Costco website, the Salmon Meal & Sweet Potato recipe has 1.2 Ca and 1 P. AAFCO raised the calcium-phosphorus ratio to these precise numbers (previously they have been 0.8 and 0.9).
However, some Kirkland dog food formulas have much more phosphorus — going up to twice the allowed amount. Kirkland Signature Super-Premium Adult dog formulas are an example of this. Such an amount could potentially be a problem.
Higher calcium and phosphorus amounts are ok for growing and lactating dogs. BUT they are not needed for maintenance.
If your dog is suffering from kidney and liver conditions, make sure to check with your veterinarian before feeding them Nature’s Domain food high in either calcium or phosphorus.
Nature’s Domain Dog Food Reviews
Kirkland Nature’s Domain dog food is a well-known and popular product line. The price is affordable compared to other grain-free dog food, and you get high-quality ingredients.
Many Nature’s Domain dog food reviews have been very positive. People say that dogs with food allergies love the food, and their coat is shinier.
It’s also common that a vet recommends Nature’s Domain dog food for its health benefits.
However, recent dog food reviews reveal that the food might have changed. Many people ask if the Nature’s Domain dog food recipes have been altered.
Here is one dog food review from the Costco website that perfectly sums all of these:
“This used to be our go-to dog food — great ingredients, great price. The last bag we bought, the kibble was thinner and it smelled different, and our dog will no longer eat it. Wish the recipe hadn’t changed — we’ll be looking for a replacement.”
You can read more Nature’s Domain dog food reviews on the Costco website.
Nature’s Domain Dog Food Recalls
Kirkland Signature Nature’s Domain dog food has had one recall so far.
In 2012, Diamond Pet Foods recalled several products, including Nature’s Domain dog food, because of possible salmonella contamination (FDA).
Diamond Pet Foods had been previously recalled — in 2007, during the melamine crisis (FDA). Many pet foods were a part of this recall. Nature’s Domain, however, was not one of them.
You can check all the recalls of pet foods on the official FDA webpage.
Alternatives
Maybe you are unsure about the Kirkland dog food, and want better ingredients? Check out the options below.
Blue Buffalo Wilderness Chicken Recipe Grain-Free Dry Dog Food
Kirkland Signature dog food is often compared to Blue Buffalo, and for a good reason.
The prices are similar — Kirkland is a little cheaper. But the ingredients in Blue Buffalo are better.
The crude protein is much higher and comes from whole meat sources. Furthermore, all the Omega-3 sources are specified.
Taste of the Wild Pacific Stream Grain-Free Dry Dog Food
This is probably the most comparable food to Kirkland Nature’s Domain Salmon Meal & Sweet Potatoes. The price is slightly higher, and the ingredients are very similar — but there are a few important differences
Specifically, the first ingredient is the whole salmon and not a salmon meal. The second ingredient is also an animal source. There are also other salmon components down the ingredients list, which shows more salmon than in Kirkland’s recipe.
Unlike Nature’s Domain, this formula contains taurine.
Merrick Real Texas Beef + Sweet Potato Grain-Free Dry Dog Food
This formula is more expensive than Nature’s Domain, but not that much.
However, what you get with Merrick is worth it. We are talking about multiple animal sources, whole meat as the first ingredient, pork fat, beef liver, taurine, and many other nutritional goodies.
Our Verdict
This dog food review concludes that Nature’s Domain dog food is an above-average affordable option. It is a pretty sweet bargain, and there are no super-concerning ingredients.
The main problem is the lack of animal protein sources and the exclusion of taurine. Additionally, be careful with the calcium and phosphorus ratio in Nature’s Domain formulas.
Domain’s Nature dog food is a great option if we are looking strictly at the affordability-to-quality ratio. Some of the ingredients, like dried chicory root and probiotics, are amazing for the price.
They are fantastic additions — but there are better alternatives for the stuff that dog foods should focus on.
