Dr. H.R. Hornbaker was the original owner of Knox Pet Clinic, and when Dr. Donald Reeder graduated from the University of Illinois in 1960, he purchased it from him. The practice was located on East Main Street in Galesburg, Illinois, but was moved to West Main Street when Dr. Reeder built the clinic’s current facility. The practice was known as Knox Veterinary Clinic.
Originally, the practice served 90% farm animals and only 10% pets, but the number of pets served increased beginning in 1969, when Dr. Harold W. Watters joined the clinic after two years of service in the military. In 1975, the building was expanded to provide the waiting room and large exam room as well as the second floor.
Dr. Benton C. Allen joined the practice in 1975, and in 1985, Dr. Reeder retired. In 1986, the practice opened a second location at 105 S. Public Square in Knoxville. Farm calls were discontinued in 1988 and the practice began to see pets exclusively. Dr. Brian K. Siever joined the clinic in 1999. He became business partners with Dr. Watters in June 2006, when the name of the practice was changed to Knox Pet Clinic. In January 2016, Dr. Siever became the sole owner.