FETAL SEX DETERMINATION IN CATTLE AND HORSES BY ULTRASONOGRAPHY

The demand for clinical diagnosis of fetal sex (gender) in the bovine and equine is increasing. Fetal gender can be accurately determined in cattle and horses by ultrasonic location of the fetal genital tubercle. During differentiation the genital tubercle migrates from the initial position between the rear legs, toward the umbilical cord in male fetuses and toward the tail in female fetuses. Transrectal examinations were conducted utilizing a real-time diagnostic scanner equipped with a linear-array 5 mHz transducer. Observations included fetal sex, location score and certainty score. The optimal age for gender diagnosis in equine and bovine fetuses was 59-68 days post ovulation. Accuracy of diagnosis was 100% when certainty scores were maximal, which occurred in 58.7% of determinations in horses and in 67.0% of determinations in cattle, under field conditions.