Contagious ecthyma

Above, gross lesions corresponding to contagious echtyma on the lips of a sheep.
Below, on the left, a microscopy image of the lesions can be seen, showing the irregularity of the epithelial surface, which exhibits ballooning degeneration as well as invasion of the mucosal lamina propria by irregular columns of epithelium (H&E, 40x). On the right, note the epithelial hyperplasia forming columns that plunge deep into the oral mucosal lamina propria (H&E, 100x).