Few dog food ingredients spark more controversy than "by-products." Many pet owners see them as garbage ingredients to avoid at all costs. But the reality is more nuanced — and understanding what by-products actually are may change your perspective.
Quick Answer
| Ingredient | What It Is | Quality |
|---|---|---|
| Chicken By-Product Meal | Organ meats, necks, feet from chickens | Can be nutritious |
| Meat By-Products | Organs from various unnamed animals | Concerning (vague) |
| Chicken By-Products | Fresh organs from chickens | Can be nutritious |
| Animal By-Product Meal | Unknown animal sources | Avoid (too vague) |
Key distinction: Named by-products (chicken, turkey, beef) are often nutritious. Unnamed by-products (meat, animal, poultry) are concerning.
What Are By-Products, Exactly?
AAFCO Definition
According to AAFCO, chicken by-products are:
"The clean parts of slaughtered chicken such as heads, feet, viscera (internal organs), free from fecal content and foreign matter, except in such trace amounts as might occur unavoidably in good factory practice."
What's Included
Chicken by-products contain:
- Liver — Highly nutritious, rich in vitamins A, B, iron
- Heart — Excellent protein source, high in taurine
- Gizzards — Lean muscle meat
- Kidneys — Good protein and B vitamins
- Lungs — Protein source
- Necks — Meat and cartilage (natural glucosamine)
- Feet — Cartilage and collagen
What's NOT Included
Contrary to popular belief, by-products do NOT contain:
- Feathers — Specifically excluded by AAFCO
- Beaks — Not in quality by-products
- Feces — Explicitly prohibited
- Floor sweepings — A persistent myth
- Diseased tissue — Must be from healthy animals
The Nutritional Value of Organ Meats
Here's what many people don't realize: organ meats are often MORE nutritious than muscle meat.
Nutrient Comparison
| Nutrient | Chicken Breast | Chicken Liver |
|---|---|---|
| Protein | 31g per 100g | 27g per 100g |
| Vitamin A | 0% DV | 267% DV |
| Vitamin B12 | 6% DV | 281% DV |
| Iron | 5% DV | 50% DV |
| Folate | 1% DV | 140% DV |
Liver is a superfood — packed with vitamins, minerals, and bioavailable nutrients.
What Dogs Ate Historically
When dogs (and their wolf ancestors) killed prey, they ate the organs FIRST:
- Liver and kidneys for vitamins
- Heart for protein and taurine
- Stomach contents for fiber and plant matter
The "premium" muscle meat we prize is actually what wild canids eat last.
Named vs. Unnamed By-Products
This is the critical distinction most people miss.
Named By-Products (Generally Fine)
- Chicken by-product meal — From chickens only
- Turkey by-products — From turkeys only
- Beef by-products — From cattle only
- Pork liver — From pigs only
You know exactly what animal the ingredient comes from. Quality can be verified and traced.
Unnamed By-Products (Avoid)
- Meat by-products — What animal? Unknown
- Poultry by-products — Chicken? Turkey? Duck? Unknown
- Animal by-product meal — Could be anything
- Meat and bone meal — Vague and low quality
When the source isn't named, you can't verify quality. It could vary from batch to batch.
Why This Matters
Named sources allow:
- Traceability if problems arise
- Consistent nutrition across batches
- Verification of quality standards
Unnamed sources may include:
- Variable animal sources
- Lower quality control
- Potentially problematic ingredients
By-Product Meal vs. By-Products
By-Products (Fresh)
- Contains moisture (~70%)
- Found in wet foods or fresh pet food
- Weighed before processing
- Similar issues to fresh chicken (see Chicken Meal vs. Chicken)
By-Product Meal (Rendered)
- Dried, concentrated (~10% moisture)
- Found in dry kibble
- More concentrated protein
- Position on ingredient list accurately reflects content
Both can be quality ingredients when properly sourced and named.
Why Premium Brands Avoid By-Products
Marketing, Not Nutrition
Many premium brands proudly state "no by-products" because:
- Consumers perceive by-products negatively
- "By-product" sounds unappetizing
- "Deboned chicken" sounds better than "chicken by-products"
- Allows for higher price positioning
The Reality
Some "premium" formulas without by-products:
- Use pea protein to inflate protein numbers
- Rely on plant proteins over animal proteins
- Cost more without providing better nutrition
Meanwhile, some affordable foods with by-products:
- Provide genuine organ meat nutrition
- Have better amino acid profiles
- Include natural sources of vitamins
Price ≠ Quality
When By-Products ARE a Problem
Red Flags
- Unnamed sources
Meat by-products, Animal by-product meal, Poultry by-products
- Primary ingredient is by-products
Chicken By-Product Meal, Corn, Wheat, Chicken Fat...
By-products as #1 without other meat sources is concerning.
- Combined with other cheap ingredients
Meat by-products, Corn Gluten Meal, Soybean Meal, Animal Fat...
Multiple low-quality ingredients suggest cost-cutting.
Quality Indicators
- Named by-products lower on list
Chicken, Chicken Meal, Brown Rice, Chicken By-Product Meal...
By-products supplement other quality proteins.
- Specific organ meats listed
Chicken, Chicken Liver, Chicken Heart, Chicken Meal...
Individual organs are the best of both worlds — you know exactly what's included.
Reading Labels: By-Product Examples
Example 1: Quality Use
Chicken, Chicken Meal, Brewers Rice, Chicken By-Product Meal, Chicken Fat
Protein: 26%
Analysis: Multiple chicken sources, named by-products in position 4. This is supplementing other proteins with nutritious organs. Fine.
Example 2: Acceptable Use
Chicken By-Product Meal, Corn, Wheat Flour, Chicken Fat, Corn Gluten Meal
Protein: 24%
Analysis: By-products first isn't ideal, but they're named (chicken) and provide real protein. The corn and wheat are filler concerns, but the by-products aren't the problem here.
Example 3: Concerning
Meat By-Products, Soybean Meal, Corn Gluten Meal, Animal Fat, Wheat
Protein: 21%
Analysis: Unnamed "meat by-products" + multiple cheap fillers + unnamed "animal fat" = low quality formula. The vagueness is the issue.
Example 4: Misleading "Premium"
Deboned Chicken, Peas, Pea Protein, Chickpeas, Chicken Fat
Protein: 28%
Analysis: No by-products sounds good, but this is pea-heavy. After chicken's water cooks off, legumes dominate. "No by-products" doesn't mean quality.
Common Myths Debunked
Myth: By-Products Contain Beaks and Feathers
Reality: AAFCO definitions specifically exclude feathers. Quality by-products from reputable manufacturers contain organs, not waste.
Myth: By-Products Are "4D" Meat
Reality: "4D" (dead, dying, diseased, disabled) animals are supposed to be excluded from the human food chain. Major pet food manufacturers source by-products from USDA-inspected facilities processing animals fit for human consumption.
Myth: By-Products Are Floor Sweepings
Reality: This persistent myth has no basis. By-products are defined organ meats from slaughtered animals, processed in regulated facilities.
Myth: Premium Brands Are By-Product-Free for Quality Reasons
Reality: Most avoid by-products for marketing reasons. Consumers will pay more for "no by-products" regardless of actual nutritional differences.
Myth: Dogs Shouldn't Eat Organs
Reality: Organ meats are among the most nutritious foods for dogs. They provide vitamins, minerals, and amino acids that muscle meat lacks.
What About "Human-Grade"?
The Term
Some brands claim "human-grade" ingredients. This means:
- Ingredients are edible by humans
- Processed in human-grade facilities
- Meet FDA standards for human food
The Reality
"Human-grade" doesn't automatically mean better:
- Many pet food ingredients already come from human food facilities
- The term adds significant cost
- Organ meats in pet food are the same as those sold for human consumption (liver, heart, kidneys)
Is It Worth It?
For most dogs, "human-grade" claims don't justify significantly higher prices. Quality non-human-grade foods using named by-products can be equally nutritious.
Our Recommendations
Accept Named By-Products When:
- They supplement other quality proteins
- The formula has good overall nutrition
- The price/value is appropriate
- You understand they're nutritious organs
Avoid By-Products When:
- Sources are unnamed ("meat by-products")
- They're combined with multiple cheap fillers
- Quality is unverifiable
- You want to eliminate specific animal proteins (allergies)
Don't Pay Premium to Avoid:
- Named by-products in quality formulas
- Foods using "no by-products" as a selling point while loading up on legumes
Brand Examples
Brands That Use By-Products (and Can Be Quality)
- Purina Pro Plan — Uses chicken by-product meal in some formulas
- Royal Canin — Uses various by-products for specific nutrients
- Hill's Science Diet — Contains by-products for balanced nutrition
- Eukanuba — Includes by-products for organ nutrients
These are research-backed brands with veterinary nutritionists on staff.
Brands That Avoid By-Products
- Blue Buffalo — Markets "no chicken by-product meals"
- Wellness — "No meat by-products"
- Merrick — Emphasizes "deboned meat first"
- Orijen/Acana — Uses whole prey ingredients
These can be quality too, but "no by-products" isn't the reason.
Frequently Asked Questions
Are by-products bad for my dog?
Not inherently. Named by-products from quality sources (chicken by-product meal from a reputable brand) can be nutritious. Unnamed by-products (meat by-products) should be avoided.
Why do by-products have a bad reputation?
Marketing by premium brands created this perception. "No by-products" became a selling point, and consumers assumed by-products must be bad. The reality is more nuanced.
Should I avoid all foods with by-products?
No. Look at the full ingredient list, brand reputation, and whether by-products are named. A well-formulated food with chicken by-products may be better than a poor formula without them.
Are named by-products better than pea protein?
From a nutritional standpoint, yes. Chicken by-products provide animal protein with a complete amino acid profile. Pea protein is a plant protein added mainly to boost numbers cheaply.
Do wild dogs eat by-products?
Yes — wolves and wild dogs prioritize organ meats when eating prey. Hearts, livers, and kidneys are eaten before muscle meat.
Is chicken by-product meal the same as chicken meal?
No. Chicken meal is rendered muscle meat and skin. Chicken by-product meal is rendered organ meats, necks, and feet. Both can be quality protein sources, but they're different parts of the chicken.
The Bottom Line
By-products have been unfairly demonized by pet food marketing:
What by-products ARE:
- Organ meats (liver, heart, kidneys, gizzards)
- Nutritious parts of animals dogs naturally eat
- Often more vitamin-rich than muscle meat
What by-products ARE NOT:
- Beaks, feathers, or waste products
- Inherently low-quality ingredients
- Something to avoid at all costs
What matters:
- Named sources — Chicken, turkey, beef (not "meat" or "poultry")
- Overall formula — By-products should supplement, not replace quality protein
- Brand reputation — Trustworthy companies source responsibly
- Your dog's health — The proof is in how your dog thrives
Don't reject a well-formulated food because it contains "chicken by-product meal," and don't assume "no by-products" means quality.