From http://www.dogfoodinsider.com/4health-dog-food-review.html:
4Health dog food is a private label brand made for the Tractor Supply Company. It is manufactured by Diamond Pet Foods, Inc., owned by Schell and Kampeter, Inc. They are a U.S.-based pet food manufacturer with plants located in Meta, Missouri, Lathrop, California and Gaston, South Carolina. The company is a family-owned, privately-held enterprise, still managed by the Schell and Kampeter family.
The headquarters for Diamond are in Meta, Missouri and the company was founded in 1970. At that time brothers-in-law Gary Schell and Richard Kampeter bought Milling Meta Co., a producer of livestock feed and dog food. Early distribution was limited to within 100 miles of Meta, Missouri and only about 5 percent of the company’s production was dog food. Diamond expanded its manufacturing to include plants in San Joaquin County California in 1999 and Gaston, South Carolina in 2002.
TSC launched 4Health as a premium private label dog food in early 2010. The food is marketed as an affordable pet food that provides dogs of all ages and sizes with nutritional ingredients for optimal health. Since the launch they have added a grain free formula.
4Health was part of a large voluntary recall by Diamond due to Salmonella in May 2012.
