Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet vs Royal Canin Canine Hypoallergenic | Dog food comparison

Compare ingredient differences and practical choice guidance. Replace A or B to explore another candidate.

A · Food to compare

Hill's

z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

B · Food to compare

Royal Canin

Canine Hypoallergenic

Compared using current public information

What matters for this choice

This pair includes a special-purpose diet. Check its intended purpose and your veterinarian’s feeding instructions before treating it as a replacement for an everyday food.

Who is it made for?

Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

Special-purpose diet — follow veterinary direction · Daily food · Adult · Kibble (Extruded)

Royal Canin Canine Hypoallergenic

Special-purpose diet — follow veterinary direction · Daily food · Adult · Kibble (Extruded)

If the intended use matches, compare the ingredients below with foods your dog has previously eaten well.

Animal protein: sources and forms

Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

The animal ingredients in the first five entries are Hydrolyzed Chicken Liver (#2), Hydrolyzed Chicken (#3). Their forms and label specificity are explained below. Hydrolyzed Chicken Liver (#2), Hydrolyzed Chicken (#3): proteins broken into smaller fragments. This differs from intact meat; the ingredient name alone does not make the finished food an allergy diet. Soybean Oil (#9), Coconut Oil (#13), Fish Oil (#14): fat/oil sources. An animal name in a fat ingredient does not make it an additional meat-protein source.

Royal Canin Canine Hypoallergenic

Named animal protein in the first five entries: Animal-Derived Protein (Chicken, Turkey) (#4). Clearly identified animal protein sources are a strength of this label. Animal-Derived Protein (Chicken, Turkey) (#4): supplies protein from the named animals in parentheses. The sources are disclosed, but grouping them hides their individual inclusion amounts and positions. Animal Fat (Chicken, Duck, Pork) (#3), Soybean Oil (#7), Fish Oil (#9): fat/oil sources. An animal name in a fat ingredient does not make it an additional meat-protein source.

The differing animal protein sources are: A: Hydrolyzed Chicken Liver, Hydrolyzed Chicken / B: Animal-Derived Protein (Chicken, Turkey). Check the named sources and forms against ingredients you need to avoid; shared names do not establish quantities or digestibility.

Is protein supplemented with plant ingredients?

Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

No processed plant protein source is identified in the available panel. Unverified panel coverage cannot establish that these ingredients are absent.

Royal Canin Canine Hypoallergenic

Soybean Meal (Hydrolyzed Soy Protein) (#2): separated or concentrated plant protein that contributes to the declared crude protein. This is a different ingredient role from whole grains or pulses. Plant protein sources account for 1 of the first five entries. This matters if you want animal-protein-focused food: a high crude-protein percentage is not a meat-content percentage.

Therapeutic diets may select protein sources for allergy or disease management. Follow the prescribed feeding purpose rather than replacing a diet solely because it contains plant protein.

What supplies carbohydrates and fiber?

Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

Corn Starch (#1): primarily supplies carbohydrate energy rather than supplementing protein. Powdered Cellulose (#5), Dried Beet Pulp (#7): supplies dietary fiber, contributing to the food’s fiber composition rather than supplementing protein.

Royal Canin Canine Hypoallergenic

Rice (#1), Borage Oil (#10): primarily carbohydrate energy sources, also contributing the protein and fiber naturally present in the ingredient.

The differing carbohydrate energy sources are: A: Corn Starch / B: Rice, Borage Oil. Listed dietary fiber sources: A: Powdered Cellulose, Dried Beet Pulp. No corresponding source was identified in the other available list. The choice is whether to retain a familiar carbohydrate source or avoid a particular ingredient.

Some panels lack verified complete coverage. We do not claim an ingredient is absent or the recipes are identical for those products.

The editor’s ingredient insights

A · Hill's

z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

Hill’s z/d Hydrolyzed Chicken starts with corn starch, hydrolyzed chicken liver, and hydrolyzed chicken, with moderate protein and high omega-3. It is worth considering for veterinarian-guided hydrolyzed-protein feeding, not for meat-density goals.

Commentary reviewed 2026-09-22

B · Royal Canin

Canine Hypoallergenic

Royal Canin Hypoallergenic is built around rice and hydrolyzed soy protein. Its animal fat and hydrolyzed animal protein are identified as chicken, duck, pork, and turkey derivatives. This is a prescription diet for a veterinarian-guided allergy food trial, not a meat-rich allergy food. At 21% protein, 19% fat, and 4,070 kcal/kg, it should not be treated as a low-fat sensitive-stomach or weight-control formula.

Commentary reviewed 2026-09-22

Your next step

A · Hill's z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

Product details

Follow veterinary feeding instructions rather than a general calculator.

B · Royal Canin Canine Hypoallergenic

Product details

Follow veterinary feeding instructions rather than a general calculator.

Affiliate links are disclosed in the purchase options. Commissions do not determine this comparison’s order or interpretation.

Reference: analysis scores, nutrients and ingredient evidence

Scores and nutrients are reference information. Meaningful differences in intended use and ingredients matter more than small numerical gaps.

Key nutrient comparison

Compare protein, fat, fiber, ash, moisture, phosphorus, sodium, and calories in the same modal. Undisclosed values are shown as empty bars.

Hill's

Royal Canin

Protein
20.1 %
21.0 %
Fat
14.5 %
19.0 %
Fiber
Undisclosed
1.10 %
Ash
Undisclosed
Undisclosed
Moisture
10.0 %
9.50 %
Phosphorus
0.60 %
0.60 %
Sodium
0.30 %
0.40 %
Calories
3505 kcal/kg
4070 kcal/kg

Score basis comparison

Reads the top ingredient structure and animal-forward build.

Hill's

Royal Canin

Scores summarize public data under a fixed method. Read the ingredient panels and intended use to understand similarity and suitability.

Hill's

Top ingredients: Corn Starch, Hydrolyzed Chicken Liver, Hydrolyzed Chicken
Strength: Prescription purpose: allergy/skin care
Watchout: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.

Royal Canin

Top ingredients are limited
Strength: Prescription purpose: allergy/skin care
Watchout: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.

Reads how much guaranteed and extra nutrient data is disclosed.

Hill's

82.5

Royal Canin

Scores summarize public data under a fixed method. Read the ingredient panels and intended use to understand similarity and suitability.

Hill's

82.5

Data grade: PARTIAL
11 disclosed nutrient items · Protein, Fat, moisture
Conservative point: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.

Royal Canin

Data grade: PARTIAL
14 disclosed nutrient items · Protein, Fat, Dietary Fiber
Conservative point: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.

Reads whether core nutrient caution checks like Ca:P balance and calcium/phosphorus ceilings are disclosed clearly and pass.

Hill's

Royal Canin

Scores summarize public data under a fixed method. Read the ingredient panels and intended use to understand similarity and suitability.

Hill's

0 warnings / 0 fails / 3 undisclosed
Watchout: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.
Ca:P and calcium/phosphorus ceiling disclosure reads relatively clearly.

Royal Canin

0 warnings / 0 fails / 2 undisclosed
Watchout: Prescription diets should be compared by clinical purpose and veterinary direction before standard ingredient ranking.
Ca:P and calcium/phosphorus ceiling disclosure reads relatively clearly.

Hill's

This brand has a confirmed recall history. The most recent public recall noted here was the 2019 vitamin D incident.
A past recall does not automatically disqualify the current recipe, but recency, cause, and follow-up response still matter.
Scope checked: FDA · AVMA · PetRecalls · PawDiet · Dogster · manufacturer sites

Royal Canin

This brand has a confirmed public recall history, with a recent 2023 mislabeling case in public sources.
Mislabeling or multi-line recalls are best read as part of operations and quality-control context, not just the recipe itself.
Scope checked: FDA · AVMA · PetRecalls · PawDiet · Dogster · manufacturer sites

Sources for interpreting ingredients

AAFCO · Ingredient definitions Tufts · Ingredient weight and nutrition AAFCO · Corn protein ingredient definition

A · z/d Hydrolyzed Chicken Flavor Dog Food | Hill's Prescription Diet

Label analysis 2/5 · 3505 kcal/kg

Corn Starch, Hydrolyzed Chicken Liver, Hydrolyzed Chicken, Ground Pecan Shells, Powdered Cellulose, Flaxseed, Dried Beet Pulp, Hydrolyzed Chicken Flavor, Soybean Oil, Dried Citrus Pulp, Dicalcium Phosphate, Lactic Acid, Coconut Oil, Fish Oil, Calcium Carbonate, Pressed Cranberries, Glyceryl Monostearate, DL-Methionine, Potassium Chloride, Iodized Salt, vitamins (Vitamin E Supplement, L-Ascorbyl-2-Polyphosphate (source of Vitamin C), Niacin Supplement, Thiamine Mononitrate, Calcium Pantothenate, Vitamin A Supplement, Riboflavin Supplement, Biotin, Pyridoxine Hydrochloride, Vitamin B12 Supplement, Folic Acid, Vitamin D3 Supplement), L-Tryptophan, Choline Chloride, minerals (Ferrous Sulfate, Zinc Oxide, Copper Sulfate, Manganous Oxide, Calcium Iodate, Sodium Selenite), Magnesium Oxide, Mixed Tocopherols for freshness, Natural Flavors, Beta-Carotene.

ingredients-1480 · db_list:ff3589ba

B · Canine Hypoallergenic

Label analysis 1/5 · 4070 kcal/kg

쌀, 대두박(가수분해 대두단백질), 동물성 지방(닭, 오리, 돼지), 동물성 유도단백질(닭, 칠면조), 사탕무박, 혼합광물질류 합제, 대두유, 프락토올리고당, 어유, 보리지유, 금잔화 분말

ingredients-1885 · db_list:b7eee047