Hill’s Prescription Diet Z/D Canine (Dry)


Rating: ☆☆☆☆☆

Hill’s Prescription Diet Z/D Canine Dog Food is not rated due to its intentional therapeutic design.

The Hill’s Prescription Diet Z/D Canine product line includes two dry dog foods, each designed to help with the support of pets with skin or food sensitivities.

Hill's Prescription Diet Z/D Canine

Dry Dog Food

Estimated Dry Matter Nutrient Content

Protein = 19% | Fat = 15% | Carbs = 58%

Ingredients: Corn starch, hydrolyzed chicken liver, powdered cellulose, soybean oil, calcium carbonate, dicalcium phosphate, lactic acid, potassium chloride, glyceryl monostearate, choline chloride, iodized salt, 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, minerals (ferrous sulfate, zinc oxide, copper sulfate, manganous oxide, calcium iodate, sodium selenite), taurine, mixed tocopherols for freshness, natural flavors, beta-carotene

Fiber (estimated dry matter content) = 4.3%

Red items indicate controversial ingredients

Estimated Nutrient Content
Guaranteed Analysis19%15%NA
Dry Matter Basis19%15%58%
Calorie Weighted Basis17%31%52%
Protein = 17% | Fat = 31% | Carbs = 52%

The first ingredient in this dog food is corn starch, a starchy powder extracted from the endosperm found at the heart of a kernel of corn. Corn starch is most likely used here to thicken the broth into a gravy.

Corn starch isn’t a true red flag item. Yet we’ve highlighted here for those wishing to avoid corn-based ingredients.

The second ingredient is hydrolyzed chicken liver, organ meat that’s been chemically broken-down into its component amino acids. Hydrolyzed proteins are considered hypoallergenic.

The third ingredient is powdered cellulose, 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.

The fourth ingredient is soybean oil 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.

The fifth ingredient is calcium carbonate, likely used here as a dietary mineral supplement.

The sixth ingredient is 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 two notable exceptions

First, 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 Z/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, you must consult your veterinarian.

With that understanding…

Judging by its ingredients alone, Hill’s Prescription Diet Z/D Canine Ultra looks like an 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.

The dashboard displays a dry matter protein reading of 19%, a fat level of 15% and estimated carbohydrates of about 58%.

And a fat-to-protein ratio of about 76%.

Below-average protein. Near-average fat. And above-average carbs when compared to a typical dry dog food.

Free of any plant-based protein boosters, this looks like the profile of a kibble containing a limited amount of meat.

Bottom line?

Hill’s Prescription Diet Z/D Canine is a plant-based dry dog food using a limited amount of hydrolyzed chicken liver as its main source of animal protein.

However, due to its intentional therapeutic design, this dog food is not rated.

Hill’s Prescription Diet Dog Food
Recall History

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.

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Notes and Updates

09/24/2016 Last Update