Histopathological evaluation of myocardium from A) uninfected control pig, B) Case 1, pig that died at 5dpe, FMDV A24 Cruzeiro. Multifocal myocardial necrosis and fragmentation (*) with interstitial edema and mixed mononuclear infiltrates consisting of small mononuclear cells with sparse to modest cytoplasm, large macrophage-like cells, few spindle cells (←) and scarce neutrophils. C) Case 2, Myocardium from pig that died at 3 dpe, FMDV O1 Campos. Multifocal myocardial degeneration and rare necrosis (*) with interstitial edema and cardiomyocyte atrophy and cytoplasmic vacuolization. Mild mixed mononuclear infiltrates consisting of mainly spindle shaped cells with elongated nuclei (←) and small mononuclear cells. Hematoxylin & eosin stain, scale bars = 25 μm.