Retained Fetal Membranes.

Retained Fetal Membranes.
Stage 3 of parturition: delivery of the fetal membranes. They are normally delivered within 3 to 6 hours. A knot is tied in the portion of the membranes that is hanging our the vulva to prevent the mare from stepping on the membranes or catching them on something.

Shipley C (2006)