408 DISEASES OF CATTLE. 



Ill blackleg the animals aflfected 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 be opened, 

 a bloody serum will exude, and the contained gas gives off the odor 

 of rancid butter. The internal hemorrhages are not general, al- 

 though they may occur. A microscopic examination of the juices 

 from the tumefaction will show the blackleg bacillus. 



In cerebro-spinal meningitis the causative agent is unknown, but 

 probably exists in the food. 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 corn- 

 stalk 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 aff'ected with 

 hemorrhagic septicemia, it would be well to examine the articular 

 surfaces of the long bones, as it has been reported that they are fre- 

 quently 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 sanitai-y precautions, such as isolation, dis- 

 infection, and burial or burning of all dead carcasses, should be 

 observed as for anthrax and other highly infectious diseases. Sepa- 

 rate the apparently well animals from the sick by placing them in a 

 separate, noninfected lot. Leave them here for a few days, and if 

 any new cases develop change the well ones again. Thoroughly dis- 

 infect all the premises, barns, stalls, litter, and stable utensils. 



VESICULAR ERUPTION OF THE GENITAL pRGANS. 



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 fi'om Hungary, 492 head of cattle were 

 attacked during 1898, 587 in 1899. and 207 in 1900. 



A similar or perhaps identical disease of horses has the same dis- 

 tribution and is transmissible from horses to cattle and vice versa. 



The disease may be defined as a highly contagious eruption situated 

 upon the external genital organs of both sexes and accompanied with 



