Hill’s Prescription Diet D/D Canine Dog Food is not rated due to its intentional therapeutic design.
The Hill’s Prescription Diet D/D Canine product line includes three dry recipes, each designed to help in the treatment of food sensitivities that can cause skin or digestive issues.
The following is a list of recipes available at the time of this review.
- Hill’s Prescription Diet D/D Canine Potato and Duck
- Hill’s Prescription Diet D/D Canine Potato and Salmon
- Hill’s Prescription Diet D/D Canine Potato and Venison
Hill’s Prescription Diet D/D Canine Potato and Duck was selected to represent the other products in the line for this review.
Hill's Prescription Diet D/D Canine Potato and Duck
Dry Dog Food
Estimated Dry Matter Nutrient Content
Ingredients: Potato, potato starch, duck, potato protein, pork fat, soybean oil, natural flavor, dicalcium phosphate, lactic acid, fish oil, powdered cellulose, potassium chloride, iodized salt, calcium carbonate, duck by-product meal, choline chloride, vitamins (vitamin E supplement, l-ascorbyl-2-polyphosphate (source of vitamin C), niacin supplement, thiamine mononitrate, vitamin A supplement, calcium pantothenate, biotin, vitamin B12 supplement, pyridoxine hydrochloride, riboflavin supplement, folic acid, vitamin D3 supplement), dl-methionine, taurine, minerals (ferrous sulfate, zinc oxide, copper sulfate, manganous oxide, calcium iodate, sodium selenite), l-tryptophan, mixed tocopherols for freshness, phosphoric acid, beta-carotene, natural flavors
Fiber (estimated dry matter content) = 1.7%
Red items indicate controversial ingredients
|Estimated Nutrient Content|
|Dry Matter Basis||18%||16%||58%|
|Calorie Weighted Basis||16%||35%||50%|
The first ingredient in this dog food 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 second ingredient is potato starch. Potato starch is a gluten-free carbohydrate of only modest nutritional value to a dog.
The third ingredient is duck. Although it is a quality item, raw duck contains about 80% 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 fourth 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 fifth ingredient is pork fat, a product from rendering pig meat.
Commonly known as lard, pork fat can add significant flavor to any dog food. And it can be high in linoleic acid, an omega-6 fatty acid essential for life.
Although it may not sound very appetizing, pork fat (in moderate amounts) is actually an acceptable pet food ingredient.
The sixth ingredient is soybean oil, which is red flagged here only due to its rumored (yet unlikely) link to canine food allergies.
However, since soybean oil is high in omega-6 fatty acids and contains no omega-3’s, it’s considered less nutritious than flaxseed oil or a named animal fat.
After the natural flavor, we find dicalcium phosphate, likely used here as a dietary calcium supplement.
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, this recipe includes fish oil. Fish oil is naturally rich in the prized EPA and DHA type of omega-3 fatty acids. These two high quality fats boast the highest bio-availability to dogs and humans.
Depending on its level of freshness and purity, fish oil should be considered a commendable addition.
Next, powdered cellulose is a non-digestible plant fiber usually made from the by-products of vegetable processing. Except for the usual benefits of fiber, powdered cellulose provides no nutritional value to a dog.
In addition, we find duck by-product meal, a dry rendered product of slaughterhouse waste. It’s made from what’s left of a slaughtered duck after all the prime cuts have been removed.
In addition to organs (the nourishing part), this stuff can contain almost anything — feet, beaks, undeveloped eggs — anything except feathers.
On the brighter side, by-product meals are meat concentrates and contain nearly 300% more protein than fresh duck.
In any case, although this item contains all the amino acids a dog needs, we consider duck by-products an inexpensive, lower quality ingredient.
Next, we find no mention of probiotics, friendly bacteria applied to the surface of the kibble after processing to help with digestion.
And lastly, the minerals listed here do not appear to be chelated. And that can make them more difficult to absorb. Non-chelated minerals are usually associated with lower quality dog foods.
Hill’s Prescription Diet D/D Canine Dog Food
The Bottom Line
Although this is a prescription product, our review has nothing to do with the accuracy of claims made by the manufacturer as to the product’s ability to treat or cure a specific health condition.
So, to find out whether or not this dog food is appropriate for your particular pet, it’s important to consult your veterinarian.
With that understanding…
Judging by its ingredients alone, Hill’s Prescription Diet D/D Canine appears to be a average dry product.
But ingredient quality by itself cannot tell the whole story. We still prefer to estimate the product’s meat content before concluding our report.
As a group, the brand features an average protein content of 18% and a mean fat level of 16%. Together, these figures suggest a carbohydrate content of 58% for the overall product line.
And a fat-to-protein ratio of about 88%.
Below-average protein. Near-average fat. And above-average carbs when compared to a typical dry dog food.
When you consider the protein-boosting effect of the potato protein, this looks like the profile of a kibble containing a limited amount of meat.
Hill’s Prescription Diet D/D Canine is a plant-based dry dog food using a limited amount of duck, salmon or venison as its main sources of animal protein.
Hill’s Prescription Diet 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.
- Hill’s Science Diet Dog Food Market Withdrawal of November 2015 (11/29/2015)
- Hill’s Science Diet Dog Food Recall June 2014 (6/3/2014)
To learn why our ratings have nothing to do with a product’s recall history, please visit our Dog Food Recalls FAQ page.
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A Final Word
The descriptions and analyses expressed in this and every article on this website represent the views and opinions of the author.
The Dog Food Advisor does not test dog food products.
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Each review is offered in good faith and has been designed to help you make a more informed decision when buying dog food.
However, due to the biological uniqueness of every animal, none of our ratings are intended to suggest feeding a particular product will result in a specific dietary response or health benefit for your pet.
For a better understanding of how we analyze each product, please read our article, "The Problem with Dog Food Reviews".
Remember, no dog food can possibly be appropriate for every life stage, lifestyle or health condition. So, choose wisely. And when in doubt, consult a qualified veterinary professional for help.
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Notes and Updates
06/26/2015 Last Update