No. 6. DEPARTMENT OF AGRICULTURE. 513 



animal most constantly affected, but it is seen not infrequently in 

 wolves, foxes, hyenas and jackalls. Rabies in the cat is relatively 

 rare and usually caused by the bite from a dog with which it is 

 associated. Cattle, sheep and goats are affected in relatively about 

 the same degree, cattle and sheep being especially exposed. It is 

 more rarelv seen in the horse. Swine contract the disease less fre- 

 quently than other domestic animals. 



The money losses from this source reach a very high figure. In 

 the State of Pennsylvania the loss of stock each year is not inconsid- 

 erable, although not reaching a very high figure. During the past 

 year in one herd of sixty cows, eleven died of rabies, worth about 

 IGOO.OO. SeA'eral outbreaks have occurred also among sheep, in 

 one tlock twenty out of fifty having died. 



In England the losses among deer in several parks have been 

 very heavy. In 1889 rabies appeared among the fallow deer at 

 Richmond, and soon after in the park of the Marquis of Bristol. In 

 the course of three months more than -4.50 died out of the herd, 

 which contained betw'een GOO and 700 animals. 



The disease is rarely transmitted from one of the domestic an- 

 imals to another. Bites from these animals are less dangerous 

 than from dogs on account of the blunt character of their teeth, 

 which inflict contused wounds rather than punctured ones. The 

 disease may, however, be transmitted in this way, and also by the 

 deposit of virulent saliva on wounds of the skin by licking. Deer 

 are said to be able to transmit the disease to others by biting. 



Cause of the Disease. Nature of the Virus. Although we 

 have every reason to believe that rabies is due to a specific germ, 

 all attempts to isolate it have so far failed. We, how^ever, under- 

 stand much of the nature of the virus, the condition which affect it, 

 etc. 



In rabid animals it is found principally in the saliva and in the 

 central nervous system, although it is known to pass sometimes 

 into other glands as the lachrymal and pancreas and also into the 

 milk. It has never been found in the blood or in any of the organs 

 such as the liver, spleen and kidneys, nor is it ever contained in the 

 muscular tissues. The contents of the stomach may contain it, 

 owing to the swallowing of the saliva previous to the paralysis 

 of the throat. It affects principally the central nervous system, 

 and it is found most certainly, and in the most concentrated condi- 

 tion in the medulla oblongata. The virus may be present in the 

 saliva for at least three days before the animal shows any symp- 

 toms of madness, as proven by Roux and Nocard, and, perhaps, as 

 long as eight days. It may be present in the central nervous system 



33—6—1001 



