Clinical report

Abstract

Thin soles have been identified as a major economic problem in large confinement dairy operations, particularly in the United States. These case studies are from two herds, one in the midwest (Herd 1) and the other in the southeast (Herd 2). Herd 1 and Herd 2 had 3,221 and 2,200 lactating cows, respectively, with records of lameness events over a 12-month period. The incidence of thin soles reported in farm records was 30.1% and 12% for Herds 1 and 2, respectively. A diagnosis of thin soles was based on criteria established in a previous study, which include a soft flexible sole on thumb pressure and a short dorsal wall (less than 3 inches; 7.5 cm). Rear feet were more commonly affected. Break or separation of the sole from the white line adjacent to zones 1 and 2 was a consistent finding in severe cases, and was termed a thin sole-induced toe ulcer (TSTU). Thin sole-induced toe ulcer lesions progressed to a subsolar abscess in zone 5, which in the worst cases progressed to septic osteitis of the third phalanx with osseous sequestration. Thin sole-induced toe ulcer is often reported as white line disease, toe abscess or sole abscess, which leads to inaccurate on-farm lesion recording and misdirected management strategies. The objective of this communication is to distinguish between laminitis-induced toe ulcer, thin sole-induced toe ulcer and white line disease. The treatment approach adopted in the study herds is discussed.