Freemartin, Polledness intersex syndrome
Anomaly of the genitals of females, mainly due to the birth of opposite-sex twins. In such females, as a rule, the vagina is shortened, the vaginal part of the cervix is absent, the size of the uterus is reduced, underdeveloped. The ovaries of the female - freemartins are externally similar to the testes, therefore this pathology is also called false hermaphroditism. The origin of freemartins is explained by the presence of anastomoses between the vessels of the chorions of neighboring fetuses, through which male hormones penetrate to the female fetus, causing its masculinization. At the birth of twins, 30% will give birth to 2 males, 30% - 2 females and 40% - males and females, 80-90% of the latter are infertile. Clinical signs. Freemartins are characterized by a bovine appearance, genital anomalies, and chimerism of erythrocytes and lymphocytes produced by different cell lines. To define freemartinism in females, genes from the Y chromosome are used as markers of cellular chimerism. Animal blood is required to determine chimerism. The frequency of occurrence of freemartinism in goats is currently not precisely established, but is about 1%. Studies on infertile goats have shown that in these animals, cellular chimerism occurs with a frequency of 4.85%.