SHOREVIEW, Minn. – Land O’Lakes Purina Feed LLC voluntarily recalled certain varieties of poultry feed products due to lack of added vitamin D in the products.

The omission of vitamin D occurred because of a formulation software conversion, according to the company. There have been no reported animal illnesses involving the recalled products. The feed was manufactured between May 23 and July 20 at plants in Milford, Ind., Nashville, Tenn. and St. Joseph, Mo. feed plants, and distributed nationwide under the Purina and DuMOR brand names.

"We are working diligently with retailers and distributors to notify customers about this issue and, as a precautionary measure, we urge customers to not feed their flocks these products," said Dave Hoogmoed, chief operating officer. "Instead, please return them to the point of purchase for a refund and replacement feed. We deeply regret the concern and inconvenience this is causing."

Birds with inadequate levels of dietary vitamin D for more than 2 to 3 weeks may have bone weakness, and can be vulnerable to fractures or joint problems or risk death. Birds living outdoors may not experience symptoms because natural vitamin D occurs within the bird’s body with daily exposure to direct sunlight.