More dog food is being recalled across the nation after potentially toxic levels of vitamin D were discovered.

Hill's Pet Nutrition expanded the recall after it received complaints of pet illnesses.

The USDA issued an alert about the recall of 33 varieties of canned dog food made by Hill's.

According to the FDA "Vitamin D is a nutrient that helps dogs regulate the balance and retention of calcium and phosphorus, but it also can cause serious health problems in dogs when too much is consumed"

The expansion came after the FDA requested Hill's test samples that were not part of the original recall, the agency said Thursday in its statement. Hill's conducted that testing, which led to the expanded recall.