543 



consists of the successive inoculation of portions of tlie nerve matter 

 containing the virus from a rabid animal, which has been exposed to 

 the atmosphere for thirteen daj^s, ten days, seven da^-s, and four 

 days, until the Airulent matter which w411 produce rabies in any 

 unpi-oteeted animal can be inoculated with impunity. A curious 

 result of the experiments of M. Pasteur is that an animal which has 

 first been inoculated with a Airus of full strength can be protected 

 by subsequent inoculations of attenuated virus repeated in doses of 

 increasing strength. 



In the horse rabies is invariably the result of the bite of a rabid dog 

 or other rabid animal. From the moment of inoculation a variable 

 time elapses before the development of any symptoms. This time 

 may be eight days, or it may be several months; it is usually about 

 four weeks. The first symptom is an irritation of the original wound. 

 This wound, which may have healed completely, commences to itch 

 until the horse rubs or bites it into a new sore. The horse then 

 becomes irritable and vicious. It is especially susceptible to sur- 

 rounding media; excessive light, noises, the entrance of an attendant, 

 or any other disturbance will cause the patient to be on the defensive. 

 It apparently sees imaginary objects; the slightest noise is exaggerated 

 into threatening violence; the approach of an attendant or another 

 animal, especially a dog, is interpreted as an assault and the horse 

 will strike and bite. The violence on the part of the rabid horse is 

 not for a moment to be confounded with the fury of the same animal 

 suffering from meningitis or any other trouble of the brain. In rabies 

 there is a volition, a premeditated method, in the attacks which the 

 animal will make, Avhich is not found in the other diseases. Between 

 the attacks of fury the animal may become calm for a variable period. 

 The vrriter attended a case in which, after a violent attack of an hour, 

 the horse was sufficiently calm to be walked 10 miles and only devel- 

 oped violence again an hour after being placed in the new stable. In 

 the period of fury the horse will bite at the reopened original wound; 

 it will rear and attempt to break its halter and fastenings; it will bite 

 at the woodwork and surrounding objects in the stable. If the animal 

 lives long enough it shows paralytic symptoms and falls to the ground, 

 unable to use two or more of its extremities, but in the majcjrity of 

 cases, in its excesses of violence, it does physical injury to itself. It 

 breaks the jav/s in biting at the manger, or fractures other bones in 

 throwing itself on the ground, and dies of hemorrhage or internal 

 injuries. At times throughout the course of the disease there is an 

 excessive sensibility of the skin, which, if irritated by the touch, will 

 l)ring on attacks of violence. The animal may have appetite and 

 desire water throughout the course of the disease, but on attempting 

 to sv.allow has a spasm of the throat, which renders the act impossible. 

 This latter condition, which is common in all rabid animals, has given 

 the disease the name of hydroxiliohia (fear of water). 



