How to Assess Equine Fetal Viability by Transrectal Ultrasound Evaluation of Fetal Peripheral Pulses

The most significant ultrasound parameters indicating viability of the equine fetus include fetal heart rate and fetal activity. Abnormal patterns in fetal heart rate reactivity represent the most sensitive indicator of fetal compromise. In advanced to late gestation, the fetal cardiac area becomes quite inaccessible to an ultrasound examination per rectum. Peripheral arterial pulses may be used instead to evaluate changes in fetal heart rate. Fetal external carotid pulse is easily accessible by ultrasound examination per rectum in advanced gestation and may provide a useful diagnostic tool for the clinician in practice. Authors’ addresses: XY Equine Veterinary Services, Select Breeders Service Ireland, Hodgestown, Donadea, Naas, Co. Kildare, Ireland (Bucca, Carli); and The Irish Equine Centre, Johnstown, Naas, Co. Kildare, Ireland (Fogarty); e-mail: [email protected] (Bucca). © 2007 AAEP.