[Illustration: FIG. 97.—Staphylococcus pyogenes.]
[Illustration: FIG. 98.—Streptococcus pyogenes.]
The forms of bacteria that may cause blood poisoning are the Staphylococcus pyogenes aureus and albus (Fig. 97), Streptococcus pyogenes (Fig. 98), Bacillus pyocyaneus, Bacillus coli communis, and the bacillus of malignant oedema (Figs. 99 and 100). The latter is included with the bacteria that produce blood poisoning because it is a frequent cause of wound septicaemia. Subcutaneous, punctured, lacerated, contused and deep wounds without suitable drainage are the most suitable for the development of and infection of the tissues with the above germs. Wound infection is most common during hot weather.
The symptoms are both general and local. The tissues in the region of the wound become swollen and painful. In malignant oedema the swelling pits on pressure, and if the wound is open, the surface becomes soft and may slough. The body temperature may be several degrees above the normal, the appetite is impaired or the animal stops eating and acts sleepy. A small amount of highly-colored urine may be passed. Nervous symptoms, such as muscular twitching, excited condition, delirium and paralysis, may be noted.
[Illustration: FIG. 99.—Bacillus of malignant oedema, showing spores.]
[Illustration: FIG. 100.—Bacillus of malignant oedema.]
The prognosis is unfavorable. In pyaemia the animal may live from a few days to several months. Septicaemia usually terminates fatally in from two to ten days.
The treatment is largely preventive. Wounds should be given prompt attention. They should be freed from all foreign substances and washed with a disinfecting solution. A contused-lacerated wound should not be sutured if this interferes with the cleansing of it, and the escape of the wound secretions. All punctured wounds should be enlarged so as to permit of treatment and drainage.
HEMORRHAGIC SEPTICAEMIA.—An acute infectious disease of ruminants and swine, characterized by hemorrhages in the different body tissues that appear as small red spots or blotches.
The specific cause of this disease is the Bacillus bovisepticus (Fig. 101). This bacillus probably enters the body tissues by way of the lining membrane of the intestinal and respiratory tracts. In the northern States, cattle pasturing on marsh lands and swampy pastures are more often affected with the disease in the late summer and fall than at other seasons of the year.