We observed the external genitalia and uterus of a 24-month-old freemartin Hanwoo. The vulva was smaller than observed in a normal female Hanwoo, while the clitoris was larger in the freemartin. The angle between the external genitalia and the perineum also varied. Upon internal genital examination, the uterus of the freemartin was a thin tube approximately 18 cm in size and had not differentiated into a normal uterus and uterine horns.

This study was conducted to detect the Y-specific DNA in the blood of the female calf in bovine heterosexual production. Genomic DNAs of the freemartin were isolated from the blood and amplified with Y-chromosome specific DNA primer(l4lbp). In order to estimate the lower limit for the detection of XY cells, blood from a hull was diluted in cow blood to 0.01%. DNA sequencing on the PCR products was shown the same sequences as Y chromosome DNA of the normal cows. The Y specific DNA hand by PCR was detected all blood of female calf suspected to have bovine freemar tin syndrom and the karyotyping with freemartin blood was identified as XX / XY chimerism. Therefore, the PGR methods used in this study was very useful technique for the detection of freemartin in Ranwoo and Holstein.