Gender determination in equine fetuses between days 50 and 90 of pregnancy

For fetal gender determination, 169 thoroughbred mares were examined with u ltrasound between Days 50 and 70 of pregnancy. Sex differentiation was base d on the position of the genital tubercle (GT), which during this time wind ow can be located in male fetuses close to the umbilicus and in female fetu ses close to the tail. Evaluation of a total of 195 examinations revealed t hat video-recordings almost doubled the chance to correctly diagnose gender , which was confirmed at birth. Overall, a diagnosis could be achieved in 9 9 mares only (50.7%), which was correct in 85%. In mares examined between D ays 60 and 70, a diagnosis was possible in 46 cases (72%), which was correc t in 87% (40 cases). Male fetuses were diagnosed easier due to the larger g enital tubercle.