222 DISEASES OF THE DOMESTIC ANIMALS 



but later and in dumb rabies paralysis renders swallowing water 

 impossible though the attempt is constantly made. In the second 

 stage, the animal is apt to leave home and travel great distances, 

 biting animals, man and inanimate objects, often returning to die. 

 The voice is changed into a hoarse howl, the tail droops and the 

 head is depressed with staring, glazed, injected eyes, and the 

 animal is insensible to pain, persons and surroundings; the gait is 

 unsteady, and the patient becomes emaciated and repulsive. Periods 

 of excitement and biting occur in the presence of noises and animals, 

 while alternating with exhaustion and quietness if the patient is 

 not disturbed. The third stage is shown by exhaustion and para- 

 plegia with paralysis of the lower jaw. The latter happens early 

 in what is known as the dumb or paralytic form of rabies, and the 

 lower jaw drops, the tongue is dry and covered with stringy mucus 

 and there is inability to swallow, howl or bite. The end is invari- 

 ably fatal in four to ten days. Foreign bodies are frequently found 

 in the stomach after death. 



When persons or animals have been bitten by a dog it is of the 

 utmost consequence that a correct diagnosis be established. If the 

 suspected animal is alive he should never be killed but kept in con- 

 finement for observation. If the suspected animal is dead, micro- 

 scopic examination by an expert pathologist of the vagus ganglia 

 of the suspected animal may immediately solve the diagnosis. The 

 presence of Negri bodies in Ammon's horn and lesions in the gas- 

 serian ganglion are pathognomonic. In order that the pathologist 

 may determine the diagnosis in rabies the whole head or brain of the 

 suspected patient may be sent on ice, or better, the brain may be sent 

 wholly immersed in glycerine. A certain but slower method is 

 by inoculation of a dog or rabbit with a bit of lumbar cord or 

 medulla of the suspected animal (not less than gr. y 2 ) rubbed with 

 a little sterile bouillon and injected under the dura mater of the 

 brain, or, what is easier, into the anterior chamber of the eye after 

 instillation of cocaine to render it painless. The period of incuba- 



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