ST. LOUIS (AP) — The manager of a Texas processing plant has pleaded guilty in a conspiracy to sell adulterated ingredients to pet food manufacturers.

Federal prosecutors say 48-year-old William Douglas Haning pleaded guilty to two charges Thursday in U.S. District Court in St. Louis. Sentencing for Haning has not yet been scheduled.

Haning was operations manager of a Wilbur-Ellis Co. processing plant in Rosser, Texas. The company has already paid more than $4.5 million in restitution.

Federal authorities say Wilbur-Ellis substituted lower cost ingredients for chicken and turkey meal in shipme...