copper sulfate
Copper sulfate is the standard copper supplement — an essential metal with a genuinely live veterinary debate about how much of it dog food should carry.
Also appears on labels as: copper sulphate · cupric sulfate · copper sulfate pentahydrate
What it is
The inorganic workhorse form of copper, an essential trace metal (enzymes, iron transport, pigment). The interesting story is the dose debate: veterinary hepatologists have raised real concerns about copper-associated liver disease in dogs and whether modern food copper levels run higher than ideal — an unresolved, evidence-based conversation, not an internet scare.
Why it's in pet food
Meeting the copper requirement reliably; deficiency is unequivocally harmful. The debate is about ceilings, not floors — some breeds (Bedlington terriers historically, with others under study) store copper pathologically, and hepatic copper findings in ordinary dogs have kept the question open.
How Bowlmark scores it
Scores are deterministic math over the printed label — the rules below apply to every product identically, and nothing estimates or fills in a blank.
Neutral in the engine — supplement levels aren't readable from an ingredient list, so the score doesn't guess. What a label CAN'T tell you: the milligrams. A dog with diagnosed copper-associated liver disease needs a prescription low-copper diet chosen with a vet; everyone else needs a complete food and no home copper math.
For dogs
Copper-storage susceptibility is breed-influenced and diagnosed by biopsy, not by label reading. If liver enzymes raise questions, the copper conversation belongs to your vet.
Foods that list copper sulfate
Ranked by score where scores exist. Placement here is never sold.
- Kettle Creek Farmhouse Chicken & Sweet Potato94
- Copperfield Cats Kitten Heritage Chicken & Oat Recipe93
- Meadow Farms Chicken & Oatmeal Puppy93
- Whisker & Pine Wild-Caught Salmon & Lentil Recipe93
- Copper Hollow Lamb & Brown Rice Sensitive Skin & Stomach92
- Silverbirch Feline Science Metabolic Trim High-Fiber Formula92
- Blue Buffalo Life Protection Formula Adult Dry Dog Food - Chicken & Brown Rice91
- Copper Hollow Whitefish & Potato Limited Ingredient91
Sources
Related ingredients
Further reading
Cite this page
Bowlmark. "Copper sulfate in pet food — what it is and how it scores." https://www.bowlmark.com/ingredient/copper-sulfate
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