Some sheep (Ovis aries Linnaeus, 1758) grazing on the island of Delos (Cyclades, Greece) wear fetters tying their front and hind limbs on one side. Through the study of skeletal remains, we observed various lesions they caused: greenstick subperiosteal fracture, enthesopathy of the posterior tendinous groove, lateral ligamentous ossification of the overlying tarsometatarsal joint by severe sprain, subperiosteal ossification (periostosis), luxuriant periostitis and localised, sometimes deep bone necrosis. Other animals displaying damage due to fetters are mentioned for comparison. The detection of fettering on bones is important in determining whether sheep are unattended or domestic, and in understanding the practices,...