Abstract: Freemartinism is the phenomenon that female born with co-male of heterosexual twin or multiple pregnancy is sterile, and becomes the most common type of congenital infertility in cattle. It is practically needed to develop a method of diagnosing freemartin quickly and accurately at early age, avoiding losses from rearing freemartin or eliminating fertile heterosexual twin female. In fact, freemartin itself is a potential animal model for heterochimeric symbiosis. This review summarized the diagnostic methods of freemartin via technologies of clinical examination, immunoreaction, hormone detection, cytological classification and molecular detection, emphasizing the elevation effects in accuracy and timeliness benefiting from cytomolecular technique. In the meantime, the applied production of heterosexual twin female as breeding stock and fattening resource was generalized, and its potential as animal model for solid organ transplantation, gonad development and twin-twin transfusion syndrome were also discussed. Finally, three potential ideas of heterosexual twin female, namely associations among reproductive hormone, chimerism and masculinization, the essence of chimerism from the perspective of types of chimeric tissue and chimeric time with cellular molecular and endocrinology, and taking fertile heterosexual twin female as the animal model for studying immune tolerance, were provided to promote the efficient utilization of heterosexual twin female and explore the scientific value behind them.

Key words: freemartin, fertility diagnosis, applied production