PURPOSE: To suppress the swing of a carcass suspended from an overhead conveyor, to keep a prescribed posture and to enable accurate dressing in high yield by making a shackling mechanism to be automatically rotatable over a necessary angle exclusively in a specific region.

CONSTITUTION: The objective shackling mechanism is provided with a shackle guide frame 105 fixed on a frame of a carcass dressing apparatus, a pair of guide rails fixed in the guide frame, a shackle carrier clamped in the guide rails, a shackle shaft 12 suspended from the carrier and a shackle part having a branched tip end. The shackle shaft is made to be automatically rotatable over a necessary angle exclusively in a specific region.