DISEASES OF THE NERVOUS SYSTEM. 239 



may remain unchanged for two or three days and then gradual im- 

 provement may take place, or the power to swallow may become 

 entirely lost and the weakness and uncertainty in gait more and more 

 perceptible ; then sleepiness or coma may appear ; the pulse becomes 

 depressed, slow, and weak, the breathing stertorous, and paroxysms 

 of delirium develop, with inability to stand, and some rigidity of the 

 spinal muscles or partial cramp of the neck and jaws. In such cases 

 death may occur in from 6 to 10 days from the commencement of 

 the attack. In many cases there is no evidence of pain, spasm, or 

 fever at any time during the progress of the disease, and finally 

 profound coma develops and death follows, painless and without a 

 struggle. 



In the last or mildest form the inability of voluntary control of the 

 limbs becomes but slightly marked, the power of swallowing never 

 entirely lost, and the animal has no fever, pain, or unconscious move- 

 ments. Generally the animal will begin to improve about the fourth 

 day and recovers. 



In a few cases the spinal symptoms, manifested by paraplegia, may 

 be the most prominent symptoms; in others they may be altogether 

 absent and the main symptoms may be difficulty in mastication and 

 swallowing; rarely it may affect one limb only. In all cases in 

 which coma remains absent for six or seven days the animal is 

 likely to recover. When changes toward recovery take place', the 

 symptoms usually leave in the reverse order to that in which they 

 developed, but local paralysis may remain for some time, rarely 

 persistent. 



,0n post-mortem the number of lesions observable to the naked 

 eye is in marked contrast to the severity of the symptoms noted. 

 The pharynx and larynx are inflamed in many cases, and sometimes 

 coated with a yellowish-white glutinous deposit, extending at times 

 over the tongue and occasionally a little way down the trachea. The 

 lungs are normal, except from complications following drenching or 

 recumbence for a long period. The heart is usually normal in appear- 

 ance, except an occasional cluster of hemorrhagic points on the outer 

 surface, while the blood is dark and firmly coagulated. The lining of 

 the stomach indicates a subacute gastritis, while occasionally an 

 erosion is noted. An edema is observed in the submucosa of such 

 cases. The first few inches of the small intestines likewise may show 

 slight inflammation in certain cases, while in others it is quite se- 

 vere; otherwise the digestive tract appears normal, excluding the 

 presence of varying numbers of hots, Strongylus vulgatus, and a 

 few other nematodes. The liver is congested and swollen in some 

 cases, while it appears normal in others. The spleen is, as a rule, 

 normal, and at times the kidneys are slightly congested. The bladder 

 is often distended with dark-colored urine, and occasionally a marked 



