Brand Comparison

Hill's Pet Nutrition vs Royal Canin

Hill's and Royal Canin dominate the veterinary Rx channel in both the US and UK — both WSAVA manufacturer-selection compliant, both with DACVN nutritionists on staff, both running AAFCO feeding trials and peer-reviewed research. For food-allergy work specifically, Hill's Prescription Diet z/d uses hydrolysed chicken liver; Royal Canin Hypoallergenic HP uses hydrolysed soy. Dogs that react to one Rx hydrolysed diet sometimes tolerate the other — if a dog reacts to z/d, switching to HP is a reasonable step before moving to amino-acid-level elemental diets (z/d Ultra Allergen Free, Royal Canin Anallergenic). In the UK, both are available through veterinary practices and Pets at Home Vets (prescription required). Pricing is comparable at the Rx tier (typically £60-80 for 10+ kg bags in the UK; $80-150 in the US). Hill's runs slightly broader breed-specific and senior-condition coverage; Royal Canin has deeper breed-specific depth especially for small and toy breeds. Both had significant recalls historically (Hill's 2019 elevated vitamin D; Royal Canin 2007 melamine), with no comparable recall since.

Factual comparison based on AAFCO definitions, FDA enforcement archive, and corporate disclosures. Not medical advice. Not an endorsement of either brand.