390 DISEASES OF CATTLE. 



As is well known, however, many pathogenic germs at times exist in 

 a saprophytic state, and it is not hard to conceive how a microbe may 

 cease such existence and assume parasitic or pathogenic properties 

 when the surroundings are eminently favorable. This may be a con- 

 necting link in the etiology of sporadic outbreaks of the disease where 

 every other hypothesis as to its genesis seems untenable. The disease 

 seems to occur most frequently in swampy or mucky localities or in pas- 

 tures receiving the overflow from infected fields. It is said to occur 

 usually in the spring of the year, when the melting snows and rains 

 bring to the surface the subterranean waters from rich soils contain- 

 ing nitrogenous materials in which the bacteria have been existing. 

 In a great many instances there does not seem to be any plausible 

 explanation for an outbreak of the disease and one can only surmise 

 as to its origin. 



Symptoms. — Three forms of the disease are recognized, based upon 

 the distribution of the lesions — the superficial, or cutaneous, the pec- 

 toral, or thoracic, and the intestinal form. The latter is a usual 

 accompaniment of the other two, and may be mild or severe. Natu- 

 rally, the symptoms vary according to the violence of the attack and 

 to the particular form of disease with which the animal is affected. 

 In the superficial, or cutaneous, form the presence of a swollen tongue, 

 throat, and dewlap, or even of the lower portion of the legs, gives us a 

 clew to the trouble. An entire loss of appetite occurs, and in milch 

 cows there is a diminution of the milk secretion. The temperature 

 may be only slightly elevated, but it is usually very high. Salivation 

 is set up due to the inflammation of the mouth and pharynx. Unsuc- 

 cessful efforts at eating and swallowing are made. There may be 

 difficulty in breathing, depending on the amount of involvement of 

 the larynx, trachea, bronchi, or lungs. There may be a blood-stained 

 discharge from the nostrils, and the mucous membrane of the same 

 will often show punctiform hemorrhages. The pulmonary form 

 shows the same symptoms as croupous pneumonia with a frequent 

 suffocative cough and oppressed breathing, or dyspnea. When the 

 intestines are involved the patient strains to defecate, and passes 

 shreds of intestinal mucus along with blood-stained feces. The urine 

 may also be tinged with blood. Finally a severe diarrhea takes place, 

 the animal becomes correspondingly weak, and death takes place in 

 twenty-four to thirty-six hours. Cases may die in as short a period 

 as six to eight hours, while in the pectoral form of the disease the 

 animal may linger six or eight days. Cases have been reported which 

 became chronic and in which death did not take place for a month 

 or more. In some of the cases running an acute course, symptoms 

 of toxemia are present; there is a lack of sensation of the skin, stag- 

 gering gait, trembling, eyes fixed, neck at times bent to one side, and 

 the eyes showing a wild expression. At times the animals appear as 

 if in pain and look around at the flanks. In the pectoral form they 



