If you wish, we can assist you and your veterinarian in diagnosis and genetic counseling. Affected Miniature Schnauzers are XY males with bilateral testes, oviducts, uterus and cranial vagina. PMDS dogs have oviducts, a uterus, and a remnant of the cranial vagina, in addition to male organs. Undescended testes do not produce sperm, High power microscopic view of seminiferous tubules in testes from a PMDS affected dog. The descended testis has Sertoli cells and developing sperm cells in the tubule. and can develop tumors.
Arrow indicates one uterine horn that is very dilated by fluid accumulation.
The larger testis contains a tumor. The veterinarian is unlikely to suspect this disease in a dog that looks like a male, and this can cause delay in diagnosis. Low power microscopic view of a testis from a PMDS affected canine embryo. Arrow indicates seminiferous tubule staining positive for MIS protein. Therefore, the likely cause of this syndrome is target organ resistance, and possibly a MIS receptor defect.