Sole Hemorrhage in Cattle
Sole hemorrhage is by far the most common noninfectious lesion in lame cows. It is regarded as a typical sign of laminitis but is frequently overshadowed by bruising of the sole. Blood stains in the sole of the hoof are the most commonly seen abnormality of the sole. When subclinical laminitis was first described, sole hemorrhage was considered to be an invariable clinical sign. It was thought that the arteriovenous shunts in the solear papillae were compromised, allowing blood to perfuse down the tubules, giving a brush-like appearance. Since then, solear hemorrhages have increased in prevalence. This may be due to cows being forced to stand on concrete for longer periods than previously. Bruising/trauma is more likely to occur if the horn is softened by moisture, or if the quality of the horn is reduced because of some nutritional error or because the thickness of the sole is reduced too much during hoof trimming. Interpreting the true cause of solear hemorrhages can be important.