MINNEAPOLIS (WCCO) — The FDA says a type of dog food that WCCO first reported on last fall has contributed to the death of hundreds of dogs.

Top veterinarians and the FDA are exploring a potential connection between grain-free dog food and a form of heart disease known as DCM.

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No specific brands are involved, just grain-free kibble.

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One working theory is that it’s not the lack of grains causing an issue, rather what companies put in place of it.

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The FDA says at least 75 dogs died since 2014. The agency is continuing to test pets suspected to have DCM.