“…As far as the live-stock of the United Kingdom is concerned hill sheep are thus the class of farm animals most exposed to the risks of disorders of the bones and teeth. Records exist of several bone and tooth disorders occurring in hill sheep in this country: 'cappi' (Bowes 1932;Bosworth & Stewart, 1932-33;Thomlinson, 1953-54;Fraser & Stamp, 1957;Cresswell, 1958), 'bent leg' (Elliot, OIT, Wood & Crichton, 1926;Dunlop, 1954), 'cripples' (Stewart, 1933;Piercy, 1934a, 6), osteoporosis (Butler, Nisbet & Robertson, 1957) and early loss of incisor teeth (Wallace, 1955;Fraser & Stamp, 1957). Workers in New Zealand have drawn attention to analogous disorders in sheep-rickets (Fitch, 1943;Ewer & Bartrum, 1948), 'bowie' (Fitch, 1954;Cunningham, 1957) and excessive wear of incisor teeth (Barnicoat, 1957).…”