Septic Laminitis in Sheep
(Lamellar suppuration, Toe abscess)
Septic laminitis is an acute bacterial infection of the laminar matrix of the hoof that is usually restricted to the toe and abaxial wall. The disease is sporadic and the cause variable, but cases due to Fusobacterium necrophorum and Trueperella pyogenes usually are more severe and extensive than those involving streptococci or other organisms. The organisms probably enter through fissures between the wall and sole and through vertical and horizontal fractures of wall horn. Sometimes, infection is enhanced by impaction with sand, mud, or feces; by overgrowth of the hoof; or by separation of the wall after laminitis.
Forefeet are affected more commonly. Lameness is severe, and the affected digit may be hot and tender. There may be a draining sinus above the lesion at the coronet, or the abscess may be found above the sole on the bottom of the foot. Applying pressure to various sections of the sole with the thumbs will elicit pain and help locate the pocket of infection. Affected sheep usually recover rapidly after paring of the horn to provide dependent drainage.