The effect of ultrasound therapy on tendon injury healing was studied on 12 locally available non-descript adult goats of either sex divided equally in two groups (I and II) consisting of six animals each. The superficial digital flexor tendon (SDFT) was transected and immediately repaired with nylon (2/0) using a locking loop suture pattern under atropine-triflupromazine-lignocaine epidural analgesia and strict aseptic condition. A full limb plaster of Paris cast was applied to immobilize the operated limb for 3 days. Postoperative care was similar in both the groups. In group I, the operated limb was allowed to heal without ultrasound therapy. In group II, pulsed ultrasound therapy was started 3 days after repair of tendinous injury at an intensity of 1 W/cm(2) for 10 min daily for 10 consecutive days. The animals of both groups were evaluated clinically and haemato-biochemically on days 1, 3, 7, 15, 20 and 30 postoperatively. Air tendonograms and ultrasonography were performed on days 0, 10, 20 and 30 post-tenorrhaphy. Histopathological examination of tendon biopsy samples was performed on day 30 post-tenorrhaphy. Resolution of inflammatory swelling, pain, weight bearing and tendon gliding movement was earlier in the test group than control. Rectal temperature, total leucocyte count and differential leucocyte count did not vary significantly at various stages of observation in both the groups. Serum glucose, cortisone and serum alkaline phosphatase levels increased significantly after tendon injury repair in all the animals and decreased slowly at all subsequent intervals in control group, whereas, it was near normal in the treatment group on day 30 post-tenorrhaphy. Air tendenograms and ultrasonography examinations in the test group revealed that there was a marked regression of peritendinous adhesion between the tendon and skin on day 30 post-tendon injury repaired and the tendon at the reconstructive site attained near normal thickness and density. Adhesions were present in the reconstructed site of SDFT in all animals of the control group. Histopathologically, the granulation tissue was comparatively bettered organized at the healing site in the ultrasound-treated animals.