agnosis._--The lesions of no other disease of cattle
closely simulate the vesicular eruption of foot-and-mouth disease on the
lining membrane of the mouth. When the blisters have ruptured, however, and
the resulting lesions have become contaminated by numerous secondary forms
of microorganisms, the correct recognition of the disease may be involved
in considerable difficulty.

Cowpox or horsepox may be accidentally transmitted by inoculation. But the
eruption of the "pox" goes on to the development of a pustule, while in
foot-and-mouth disease the eruption is never more than a vesicle, even
though the contained fluid may become turbid. The inoculation test in the
case of cowpox does not respond with fever and eruption for at least 10
days, and often longer.

Necrotic stomatitis (sore mouth due to a germ) may be distinguished from
foot-and-mouth disease by the fact that in the latter there is a rapid
infection of the entire herd, including the adult cattle, as well as the
infection of hogs and sheep. The characteristic lesion of foot-and-mouth
disease is the appearance of blisters containing a serous fluid upon the
mucous membrane of the mouth and upon the udder, teats, and feet of the
affected animals. In necrotic stomatitis blisters are never formed,
destruction of the tissues occurring from the beginning and being followed
by the formation of yellowish, cheesy patches, principally found involving
the lining membrane of the mouth, especially the tongue and cheeks.

In mycotic stomatitis (sore mouth due to a fungus or mold), portions of the
lining membrane become inflamed and in a few days it changes to a croupous
membrane which peels off, leaving a raw surface, while the thin skin
between the toes may also be inflamed. The previous history of the case;
the failure of the blisters, if any appear, to spread extensively; the
absence of vesicular eruptions on other portions of the body, notably the
udder and teats, and, characteristically, the hoof, together with the
absence of rapid spread to practically all cattle in the herd and the
complete negative character of inoculation of calves, distinguish between
the local disease named and foot-and-mouth disease. Mycotic stomatitis
occurs in only from 10 to 50 per cent of the animals in a herd, usually in
the late summer or early fall after a dry spell, and it does not run a
regular course.

The lesion, resulting from ergotism may be distinguished from those of
foot-and-mou