Heart of America DHIA was formed in 1995 with the merger of six state DHIA's. Our lab is located in Manhattan, Kansas. We also have district offices in Lincoln, Nebraska and Wagoner, Oklahoma. In one form or another, DHIA has been in the area since the early 1900's. We primarily serve dairymen from North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, Arkansas, and parts of Missouri, Iowa, and Colorado.