Recipient of the 2025 Inaugural IETS Distinguished Practitioner Award: Dr John F. Hasler
Dr John F. Hasler has had a distinguished career in the field of reproductive physiology and embryo transfer. He earned his BA (1966) and MA (1969) degrees in zoology from the University of Missouri–Columbia. After being drafted in 1968, he spent 2 years of service in the US Army, including 1 year in Vietnam. He received a PhD in reproductive physiology from the University of Illinois in 1974. After his PhD, Dr Hasler spent 3 years as a postdoctoral student/research associate at the Bovine Embryo Transfer Laboratory at Colorado State University, where he participated in many research projects concerning embryo transfer, including the relationship of blood progesterone concentrations and pregnancy rates in embryo transfer recipients. In 1977, he and his young family moved to Canada, where he worked in commercial embryo transfer.
In 1979, Dr Hasler co-founded Em Tran Inc. in Pennsylvania with Dr Alan McCauley. For the next 23 years, Em Tran was a dominant player in commercial embryo transfer in the United States, pioneering applications including splitting embryos, simplifying procedures for cryopreserving embryos, genotyping and sexing embryos, and especially in vitro fertilization, the latter resulting in the third most cited paper in the history of the journal Theriogenology. Em Tran was among the first organizations to establish a market for frozen embryos in several foreign countries and set industry standards for superovulation and pregnancy rate analyses. In fact, for two decades, the numerous publications from Em Tran were the benchmark for comprehensiveness, reliability, and sharing of information. Many veterinarians worked at Em Tran and Em Tran West, the California branch, and a number of them subsequently established their own successful embryo transfer practices.
In 2001, Em Tran Inc. was sold, and John and his wife, Marilyn, moved to Colorado, where he was employed as director of research for the company XY Inc., which was developing practical procedures for sexing semen. In recent years, he has worked nearly full time as a technical consultant for Bioniche Inc., and he regularly wrote columns for the American Embryo Transfer Association (AETA) and Canadian Embryo Transfer Association (CETA) newsletters.
Dr Hasler was a founding member of the American Embryo Transfer Association and served as the first secretary/treasurer of the organization. Dr Hasler also provided his services to IETS on numerous occasions. To date, he has never missed any of the 50 Annual Meetings. He served two terms on the Board of Governors, in each case as secretary/treasurer. He was chair or co-chair of three IETS meetings and was an invited speaker at seven annual meetings. He similarly served the American Embryo Transfer Association in a number of capacities and received their Embryo Transfer Person of the Year Award in 1993. He also has represented the embryo transfer industry repeatedly by giving many dozens of talks at other meetings.
His accolades include the Army Commendation Medal (1970), the Schering-Plough Animal Health Embryo Transfer Person of the Year (1992), the International Embryo Technology Society Distinguished Service Award (2014), and the American Embryo Transfer Association Lifetime Achievement Award (2014).
Dr Hasler has maintained active research collaborations with scientists at several universities and has published numerous papers involving embryo transfer, in vitro fertilization, and related technologies. He also continues to assist with research projects at Colorado State University on a regular basis. Dr Hasler has given lectures on these subjects in more than 20 foreign countries. Dr Hasler now lives in Fort Collins, Colorado, and served as a technical consultant to Vetoquinol USA Inc. in Fort Worth, Texas, before retiring on 31 December 2023.
Dr Hasler’s dedication to the embryo transfer industry and his support for young practitioners and emerging technologies make him a most deserving recipient of the Inaugural IETS Distinguished Practitioner Award for 2025.
