Luke Bass graduated from Colorado State University in 2007 and then completed an equine internship at Pioneer Equine Hospital in Oakdale, CA. After completion of the internship, he remained at Pioneer for four years as an associate veterinarian. He recently returned to CSU as a faculty member in the Equine Field Service. He has been deeply involved with American Association of Equine Practitioners (AAEP) serving on both Student Relations and Membership Development Committees. He is currently serving on the AAEP Student Programming and Internship Avenues Task Forces, with the goal of improving student experiences while in veterinary school.


In horses, development of twins is often problematic and may represent a potential life-threatening condition for the mare and both of the embryos/fetuses. There have been many attempts at various stages of gestation to reduce twin fetuses to a singleton with variable success. Recently, techniques have been described to perform transabdominal ultrasound guided cardiac injection of a toxic substance into a twin fetus. The case discussed in this report is a mare presented at 200 days with twin fetuses. Procaine penicillin was injected directly into the heart of one fetus using an ultrasound-guided approach. The ultimate outcome was birth of a live healthy filly followed by the passage of a mummified fetus. This report is the first to describe the procedure in a mare greater than 168 days of gestation leading to birth of a live foal that lived longer than three days.