Measurements and Donkey Laminitis

An advanced statistical technique was used to establish and validate an objective method of diagnosing laminitis in donkeys using measurements obtained from a lateromedial radiograph of a selected forefoot. Eighty-five donkeys with laminitis and 85 without were used in a model to produce scores to distinguish laminitic from non-laminitic donkeys.

Clinical histories of acute phase laminitis or freedom from hoof disease combined with the physical appearance of the hooves were used as the standard for a diagnosis of laminitis.

Feet of non-laminitic donkeys had greater anatomic similarity than affected donkeys. The first group of most influential measurements included angular deviation between the dorsal aspect of the coffin bone and the hoof wall at the toe, angle of the apex of the coffin bone, depth from dorsal hoof wall to dorsal surface of the coffin bone. Another group of measurements that were influential included the P2 angle and length, the angle of P1 and dorsal hoof wall angle.

The sensitivity, specificity and predictive values of the models ranged from 50% to 84%. Compared to most traditional diagnostic tests this performance would not be considered good, but the technique described may be more useful than evaluating single measurements such as rotation of the coffin bone as an objective diagnostic criteria.

It seems likely that a clinical evaluation of lameness and the hooves along with a radiographic examination will remain the standard for diagnosis of laminitis in donkeys, however, further refinement of the test method may be useful.

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