Ventral Midline Hysterectomy, Ovariectomy, and Ovariohysterectomy in Mus Musculus: A Surgical Protocol.

Mice (Mus musculus) are one of the most commonly used animal species in basic science and translational research worldwide. Ovariectomy and hysterectomy are frequently employed to explore the systemic effects of the sex-hormone axis and other pathological conditions. While several surgical protocols exist for dorsal ovariectomy in rodents, very few address a ventral midline technique, and none are specific to the mouse model. Historically, ventral midline approaches have been considered technically challenging due to unique anatomical features, including long, thin uterine horns, fragile salpinges, short ovarian suspensory ligaments, and small animal size. This protocol provides a detailed guide for performing ovariectomy, hysterectomy, or ovariohysterectomy in mice, including the microsurgical steps required. All procedures were performed using an operative stereomicroscope under 3-5x magnification. The mean weight of the mice was 24 g (SD = 2 g), with ages ranging from 19 to 21 weeks. Of the 255 surgeries performed, 3 post-operative deaths occurred, resulting in an attrition rate of 1.18%. Post-operatively, all mice were housed in groups with fresh, paddy husk bedding, and no infections or wound breakdown were observed. Despite their small size and the manipulation of several vital anatomical structures, this procedure is easily reproducible and well-tolerated in mice.