Many of these foods are labeled as “grain free” with main ingredients like peas, lentils and potatoes.
The investigation started in July 2018.
This week, the FDA released its third report in the investigation which includes 16 pet food brands linked to more than 500 cases of canine heart disease.
Those brands include Blue Buffalo, Natural Balance, Nutro and Rachel Ray Nutrish.
The FDA is asking pet owners and veterinarians to report any cases of canine heart disease.