An Unusual Case of Testicular Disorder in Sex Development of Arabian Mare (64,XX SRY-Negative).

摘要: A 3-year-old Arabian mare underwent medical examinations due to the presence of abnormalities reproductive apparatus and stallion behavior (nervous temperament, aggressiveness, masculine attitude). During clinical visit, an anovulvar distance shorter than normal was observed; moreover, vulvar lips were dorsally fused except for lower neckline, showing a blind ending from which penis-like structure protruded. The ultrasound examination revealed cervix corpus uterus, hypoplastic uterine horns, small gonads with echogenicity similar testis. Blood testosterone levels ranged 0.4 0.6 ng/mL. Cytogenetic analysis showed female karyotype (2n = 64,XX), while PCR amplification SRY ZFY genes absence Y chromosome. At necroscopic examination, internal genitalia arising genital ridge in form type structures found, those deriving Mullerian ducts feminine type. In addition, infundibular portion salpinx at cranial pole found. This is first case equine species DSD 2n 64,XX SRY-negative, simultaneous male (hypoplastic testicles, epididymal portions, structure) (cervix, horn body uterus) structures.