Dr O. J. Ginther was born and raised on a farm in Pennsylvania. Upon graduation from high school, he served in the US Air Force during the Korean War (1951–1955). He received a BSc from Pennsylvania State University in 1958, and the VMD from the University of Pennsylvania in 1961. In 1964, he enrolled as a graduate student at the University of Wisconsin under former IETS Pioneer Awardee, Dr L. E. Casida. He received his PhD in 1967 and joined the Department of Veterinary Science (now Department of Pathobiological Sciences) at the University of Wisconsin, where he has remained. In 2001, he founded the Eutheria Foundation with a mission to provide facilities, animals, equipment, supplies and personnel for scientific research into basic reproductive mechanisms in farm animals. Dr Ginther is recognised for the development of many techniques that embryo transfer practitioners take for granted, including his remarkable work on ultrasonography and the study of ovarian function in cattle and horses in particular. He is the sole author of five hard-cover text and reference books currently used worldwide by scientists, students and veterinarians. He has served as major research advisor for more than 75 graduate and postdoctoral students, many of whom have become leaders in reproductive biology.