EXOSTOSES.
SPAVIN IN THE OX.
Exostoses are somewhat uncommon in the bovine species, and when they occur are rarely of great clinical interest. Nevertheless, in cows and old working oxen one sometimes sees metatarsal spavin. Its gravity, however, appears to be very much less than in the horse, on account of its position. Very commonly there is only trifling lameness.
Treatment by application of biniodide of mercury ointment or the actual cautery gives good results. The principal precaution required is to prevent the animals licking the parts.
RING-BONE.
Ring-bones only occur in working oxen, and particularly in aged animals used in hilly regions. They result almost exclusively from wounds, ligamentous and tendinous strains, and articular injuries.
Fig. 13.—Tibia. Lesions due to open fracture and displacement. Irregular callus formation and segnestrum.
They are preceded (as can usually be proved by dissection of limbs) by fibrous or fibro-cartilaginous induration in or about the coronet or one of the phalanges. These thickenings increase the diameter of the pastern in all directions. Ring-bones are seldom very large; but as they partially or entirely surround the insertions of the lateral ligaments, inter-phalangeal articulations or insertions of the digital extensors, they are painful, and produce lameness of varying intensity.
Diagnosis is easy, partly because the tension of the skin and the fibrous thickening render palpation painful.