The Daily Racing Forum has reported that the California Horse Racing Board has lifted a ban on the use of feed products made by Purina Mills at its Turlock, California plant.

The ban was instituted last month after the company’s products resulted in 48 positive tests for the banned medication zilpaterol, which is used to build mass in livestock.

Purina executives and third party testers have made assurances that the feed no longer contains zilpaterol, and licensed feed vendors will be allowed to distribute Purina products that were milled since March 27th.

The positive tests occurred at the four racetracks operating in the state – Cal-Expo, Golden Gate Fields, Los Alamitos, and Santa Anita. The California Horse Racing Board has agreed to dismiss the 48 cases, all of which were found since March 1st.

Purina Mills Inc. is not affiliated with Agribrands Purina Canada Inc., which is the manufacturer of Purina brands in Canada.