| Gross lesions: |
| Lesions observed in animals include vesicles,
erosions and ulcers. Vesicles vary from 0.5 to 10 centimeters when they coalesce. |
|
| Lesions can be found on oral and lingual mucosa,
snout, rumen pillars, interdigital space, coronary band, heel and teats. |
|
| These vesicles progress and rupture, forming erosions
and ulcers which are generally more marked in areas where there is greater physiological
or mechanical activity. When the animals are examined it is common to find sloughing
of the epithelium. Occasionally, the entire claw may detach. |
|
| In very young animals, myocardial necrosis can occur,
appearing as pale streaks in the ventricular wall. |
|
| Secondary contamination with bacteria or
fly larvae can aggravate the virally-induced lesions. |