Beef liver is higher in protein and more pungent — better for high-value training and picky eaters. Chicken liver is lower in fat and milder in smell — a better fit for dogs with fat sensitivity or owners who find the beef liver odor overwhelming. Neither is universally superior; it depends on your dog and your situation.
In this article
Nutritional comparison
| Nutrient (per 100g dry matter) | Beef liver | Chicken liver |
|---|---|---|
| Crude protein (min) | 60% | 65% |
| Crude fat (min) | 10% | 7% |
| Moisture (max) | 7.5% | 5% |
| Vitamin A | Very high | High |
| Iron | Very high (110 mg/kg min) | High |
| Vitamin B12 | Very high | High |
| Copper | High (10 mg/kg min) | Moderate |
Chicken liver comes in slightly higher on protein per dry matter, but both are exceptional protein sources — far higher than most commercial treats. Beef liver has meaningfully more fat and more copper, which matters for dogs with specific health considerations.
Smell and palatability differences
Beef liver has a stronger, more pungent smell. It persists longer on hands and in the training pouch. Chicken liver has a milder, softer smell — still clearly a high-value treat to dogs, but less aggressive for owners who find the beef liver odor strong.
On raw palatability testing across species, liver consistently ranks highest among organ meats. The difference between beef and chicken liver is meaningful but secondary to the liver-vs-muscle-meat distinction. Most dogs show clear preference for liver over almost any other treat regardless of species.
Training value: which motivates more?
In most dogs, beef liver edges out chicken liver as a training motivator. The stronger smell travels further (useful for distance recalls and outdoor work), and the more intense flavor seems to drive slightly higher drive and focus in most dogs tested by professional trainers. The difference is not dramatic — a dog that is not motivated by chicken liver is probably a dog with low food drive generally, not a dog that needs beef specifically.
For dogs who are mildly interested in chicken liver but highly excited about beef liver, the beef version is the better training choice. For dogs who respond equally, the chicken liver's lower fat content may make it the practical choice for frequent training sessions.
Dogs who do better with each type
Beef liver is better for: high-drive working dogs needing maximum motivation; recall training in distracting environments; dogs who are picky or food-indifferent; cases where you need the strongest possible reward.
Chicken liver is better for: dogs with confirmed fat-related issues (pancreatitis history, hyperlipidemia); dogs on copper-restricted diets; handlers who find the beef liver smell excessive; situations where you're using treats in very high quantities per session and want to reduce fat load.
Which Stewart products cover each option
Stewart makes both formats in their Pro-Treat line: beef liver and chicken liver, both freeze-dried, both single-ingredient. The chicken liver comes in smaller package sizes (the tub format in 3oz, 11.5oz, and 14.8oz). Both use the same manufacturing process in Dayton, Ohio and carry the same USDA-certification.