Copper Reference — Confirmed Data Only · Draft 1.0

How to Use This Reference

This document is intended to support informed discussions with a veterinarian — not to provide feeding recommendations. Copper values should be interpreted in the context of a dog's total daily caloric intake, individual medical history, and veterinary guidance.

Comparisons in this document are relative within the subset of products evaluated and do not represent a comprehensive ranking of all available dog foods. Highlighted products represent a subset of evaluated formulas and should not be interpreted as a ranked or recommended list. Lower or higher copper values do not determine suitability for any specific dog. Individual entries labeled as "lowest" or "highest" refer only to comparisons within a specific brand or evaluated subset and should not be interpreted as cross-market rankings.

Common misinterpretations to avoid: "Lowest copper" does not mean "best" or "recommended." Copper content alone does not determine diet suitability. mg/kg values are not directly comparable across products without caloric normalization — mg/Mcal is the preferred comparison metric. Absence of a product from this reference does not imply higher or lower copper content.

Data Scope

This reference contains only values reported as provided by manufacturers via direct email correspondence or their official publications. No survey-based, community-reported, or unverified data is included. All source attributions include manufacturer name and month/year of confirmation. Absence of data for a given product or brand does not imply higher or lower copper content.

Note: Companies vary in how they report copper values. Some disclose only the supplemented amount while others report both supplemented and naturally occurring copper. Where known, the reporting approach is noted in the brand section. Petcurean explicitly reports both; others may not.

mg/Mcal Conversions

Where only mg/kg DM was provided by manufacturer, mg/Mcal was calculated using published kcal/kg caloric density per product. Values marked ~ are calculated estimates. Where kcal/kg was not available, no mg/Mcal is stated rather than estimate.

Wet Food / High-Moisture Products

For canned wet food and similar high-moisture products, as-fed copper values appear lower than dry or air-dried products due to dilution by moisture (~74–84% water). DM values and mg/Mcal are the appropriate comparison metrics across formats. Do not compare as-fed values between wet and dry products directly.

Guaranteed Analysis vs Typical Analysis

Guaranteed analysis values represent declared minimums or maximums — they are regulatory floors or ceilings, not actual measured content. Typical analysis values represent averaged laboratory measurements and are more useful for precise copper management. This reference uses typical analysis values wherever available. Where only guaranteed analysis is available, this is clearly noted and estimates are labeled accordingly.

Treat mg/treat Calculations

Calculated from confirmed mg/kg as-fed values and treat weights derived from published kcal/treat ÷ published kcal/kg. Values marked ~ are estimates. For biscuit treats, the same mg/kg value produces vastly different per-treat copper amounts depending on biscuit size; always use the per-treat value for the specific size fed.

Evidence-Based Risk Stratification

Well-established predisposition (strong, consistent peer-reviewed evidence):

Bedlington Terrier — COMMD1 mutation; strongest genetic evidence for primary copper storage disease ^[1]. Labrador Retriever — hepatic copper accumulation and genetic modifiers (ATP7A/ATP7B) well documented ^{[2] [3]}. Doberman Pinscher — chronic hepatitis with copper involvement ^[4].

Moderately established (consistent reports, often multifactorial or secondary):

West Highland White Terrier — breed-associated copper accumulation ^[5]. Dalmatian — hepatic copper accumulation ^[6]. Skye Terrier — chronic hepatitis with copper storage ^[7]. American Cocker Spaniel — chronic hepatitis patterns ^[8].

Limited or inconsistent evidence (occasional reports, weak or mixed data):

Dachshund — reported in broader chronic hepatitis cohorts; no strong breed-specific causal data. Clumber Spaniel — sporadic case reports only.

Anecdotal / occasionally reported, not widely accepted in authoritative lists:

Welsh Corgi (Pembroke & Cardigan) — mentioned occasionally in case reports and clinical discussions; no peer-reviewed consensus establishing predisposition.

CAH can develop in any breed or mixed-breed dog, particularly with increased dietary copper exposure ^{[9] [10] [11]}. The absence of a breed from the above list does not eliminate risk. Consult a veterinarian for breed-specific guidance. This list is not exhaustive and reflects the state of published evidence at the time of compilation.

References include peer-reviewed veterinary literature (PubMed-indexed) examining breed predisposition, hepatic copper accumulation, and genetic factors associated with canine copper-associated hepatopathy.