he seat of infection, but a few hours after death it may migrate
through the blood channels to other parts of the body. The bacillus may
attack man, horses, asses, goats, sheep, pigs, cats, dogs, and poultry.
Adult cattle, although refractory to experimental inoculation, suffer from
natural infection, while calves are susceptible to both these methods of
exposure. (Kitt.) The introduction of the bacillus into abrasions of the
skin and superficial sores rarely does any harm, because the germ is
quickly destroyed by contact with air. If, however, the organisms are
inserted deeply into the subcutaneous tissues of susceptible animals, they
quickly develop, producing a soluble poison, which is the fatal agent.
In lamb-shearing season, or after docking or castration, the mortality is
higher among these animals because of wounds inflicted at such times. The
application of antiseptics to wounds thus made will reduce the percentage
of deaths to a minimum.
_Symptoms._--Usually the first symptoms are overlooked. In the early stages
the animal appears listless, disinclined to move about, and lies down in
shady and quiet places. If forced to move about, the hind legs are drawn
forward with a peculiar, stiff, dragging movement, and there may be slight
muscular trembling over all the body, which becomes more intense as the
disease progresses. When driven, the animal shows signs of fatigue,
ultimately dropping to the ground completely exhausted. Breathing becomes
fast and painful, with frequent spasmodic jerks.
The pulse is quick and weak and the temperature is 106 deg. to 107 deg. F. An
edematous, doughy, and painful swelling appears at the point of infection.
This tumefaction spreads more and more, and crackles on pressure. In case
of an open wound, a fetid liquid and frothy discharge is observed. The
center of the swelling may appear soft and jellylike, while the margin is
tense, hot, and painful. The symptoms increase rapidly, resulting in coma
and death.
_Lesions._--After death the fat and subcutaneous tissues surrounding the
infected area are infiltrated with a yellow gelatinous material containing
an orange-colored foam, due to the presence of gas bubbles.
The muscles at this point are friable, spongy, and of a uniform brownish
tint, dissociated by gas and with a blood-tinged exudate. This gangrenous
tissue, when present before death, can be removed without pain to the
animal. The intestines are generally normal, but, to
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