[Gynecomastia in a goat buck].

A 3-year old horned buck of the Toggenburger breed was referred to our clinic with signs of gynecomastia. Cytogenetic abnormalities could not be detected in the karyogram and compared to control animals the buck had normal plasma concentrations of testosterone and estradiol but not prolactin. Hyperprolactinemia has been considered the cause of gynecomastia leaving the semen quality undisturbed.