The diaphragm, heart sac, and heart walls show numerous hemorrhagic points and larger bloody extravasations. Sometimes there is a serous pleurisy, with more or less fibrinous exudate. In the intestinal form the submucous and subperitoneal tissues show alterations from a few hemorrhagic spots to large bloody suffusions, or even gelatinous infiltrations. This latter is seen about the region of the pancreas and in the folds of the mesentery. There is a severe hemorrhagic inflammation of the intestines and a staining of the intestinal contents with blood. The muscular system throughout shows hemorrhagic areas. The abdominal viscera, liver, spleen, and kidneys often present hemorrhagic lesions.
Differential diagnosis.—Anthrax, which presents superficial swellings, like hemorrhagic septicemia, may be distinguished from that affection on post-mortem examination by the enlargement and engorgement of the spleen, the contents of which are soft and tarry. The blood of anthrax animals is very dark, and does not become light red on exposure to air, nor does it coagulate, while in hemorrhagic septicemia the blood is normal in appearance and coagulates. The detection of the anthrax bacillus in the blood would be final.
In blackleg the animals affected are usually under 2 years of age. The swellings are quite evident, and usually occur on the legs, above the knees or hocks, and are distended with gas, which crackles, or crepitates, when pressed upon. If one of these tumors is opened, a bloody serum will exude, and the gas gives off the odor of rancid butter. The internal hemorrhages are not general, although they may occur. A microscopic examination of the juices from the tumefaction will show the blackleg bacillus.
In cerebrospinal meningitis the causative agent is unknown, but probably exists in the feed. It may occur in any locality and at any season of the year. There are no local swellings, and cattle are not frequently affected.
Cornstalk disease may be differentiated from this affection from the fact that it always occurs after the cattle are turned into a cornstalk field, by its sudden onset, the absence of any characteristic symptoms or post-mortem lesions, and the failure to find the causative agent in the blood.
In making a post-mortem examination of animals affected with hemorrhagic septicemia, it would be well to examine the articular surfaces of the long bones, as it has been reported that they are frequently ulcerated. This should apply especially to those cases that have shown lameness.
Treatment.—Treatment is absolutely useless, so far as we know at present, and for all practical purposes prophylaxis alone should be relied upon. The same sanitary precautions, such as isolation, disinfection, and burial or burning of all dead carcasses, should be observed as for anthrax and other highly infectious diseases. All the premises, barns, stalls, litter, and stable utensils should be thoroughly disinfected. Separate the apparently well animals from the sick by placing them in a separate lot.
Experiments by the Bureau of Animal Industry toward protective inoculation of the exposed cattle on infected premises have been made and the results have been so satisfactory that several commercial houses handling biological products are manufacturing a vaccine for hemorrhagic septicemia in accordance with the Government's experiments on this subject. The method of preparing the vaccine is similar to that recommended by Lignières. It consists in growing the cultures of the organism of the disease at 42 to 43° C. and preparing from them growing at this temperature two different strengths of vaccine. The weaker vaccine, which is used for the first injection, is grown for five days at this temperature, whereas the stronger vaccine, for the second injection, is grown for only two days. These vaccines are used with an interval of 10 days between the injections, the dose being 1 cubic centimeter at each injection. The effect of this vaccine in abating outbreaks already in progress has been highly satisfactory and it is plain that the general introduction of preventive vaccination for hemorrhagic septicemia must be of material benefit to the cattle raisers in the infected districts.
VESICULAR ERUPTION OF THE GENITAL ORGANS.
This contagious disease is called coital exanthema or vesicular exanthema, and is more or less prevalent on the Continent. It has also been observed in the breeding districts of the United States. It is the subject of legislation in Germany, and governmental statistics are published annually concerning its distribution in the Empire. According to the reports from Hungary 492 head of cattle were attacked during 1898, 587 in 1899, and 207 in 1900.