Peaches
The flesh of a peach is a great source of fiber and vitamin A, but the pit contains cyanide. Cyanide interferes with cellular oxygen transport, preventing your dog’s blood cells from getting the right amount of oxygen.
Signs of cyanide poisoning include dilated pupils, red gums, and difficulty breathing. Other pitted fruits like cherries and plums pose the same problem. Be sure to cut the fruit into small pieces before feeding your dog.