390 DISEASES OF CATTLE. 



the nature of the cause. If a strictly parasitic organism, like the con- 

 tagium of pleuro-pneumouia, it might be completely extirpated in this 

 way. If, however, the germs or bacteria may live and multiply outside 

 of the bovine body, in the soil, water, or some other animal, extirpation 

 would be impossible. 



The virus may be transmitted from sick to healthy animals in a vari- 

 ety of ways, both direct and indirect. It is said to be present in the 

 various excreta of the diseased, such as the discharges from the nose 

 and the saliva, the urine, and the manure. It retains its vitality out- 

 side of the body in a moist state for months, even a year or more, 

 according to some authorities. Hence manure and the fodder and bed- 

 ding soiled with the discharges may convey the disease. When dried, 

 however, its vitality is said to be lost in a few days. Persons may 

 carry the virus on their shoes, clothing, and implements. Even small 

 animals, such as cats and rats, which frequent barns and stables have 

 been looked upon as carriers of the virus. 



Cattle are very susceptible to the disease, and in its virulent type 

 all those exposed are said to become infected. Buffaloes, sheep, and 

 goats are likewise susceptible, but in a less degree. 



It is also claimed that animals after having passed through one attack 

 are able to resist successfully future attacks. Inoculation with virus 

 is said to produce immunity, but the process of inoculation itself is 

 followed by death in many cases. 



Symiitoms. The symptoms of rinderpest are not very characteristic, 

 and hence the diagnosis of a suspected case in the beginning of an 

 invasion is attended with difficulties. Certain appearances which are 

 characteristic of one epizootic may be absent in another. Different 

 observers are not quite agreed as to the most constant and important. 



The period of incubation, i. <?., the time elapsing between the expos- 

 ure to infection and the earliest outward symptoms, varies from 3 to 9 

 days. Then the first sign is a very high fever temperature, which may 

 reach 107 F. The heat of the skin varies in different parts of the 

 body, and may be felt at the base of the ears and horns. Eepeated 

 chills are frequently observed. The pulse reaches 50 to GO beats per 

 minute, and may rise to 90 or 100 in very severe attacks. 



The animal manifests great debility. The head droops a\id rests on 

 some object of support. One or both ear's may droop. The coat is 

 staring and the muzzle dry. The secretion of milk diminishes very 

 rapidly. Within twelve to twenty hours the usual quantity may have 

 become reduced one-half or two-thirds. The back is arched, and the 

 four limbs brought together under the body. 



As the disease progresses symptoms with reference to the digestive 

 and respiratory organs become prominent. The mucous membrane of 

 the mouth, the nose, as well as that of the rectum and vagina, becomes 

 reddened either in patches or diffusely, and assumes a scarlet hue. The 

 discharges, at first firm, become softer, and soon diarrhea sets in. This 



