Tetanus. 343 



More striking and pathognomonic than the above is the extreme 

 h5'persesthesia and irritability which rouse into activity or aggra- 

 vate the symptoms under the slightest cause of disturbance." The 

 effort required to feed from the ground, the stretching of himself 

 to urinate or defecate, the rustling of straw litter under his feet, 

 loud talking, or other sudden noise, banging of doors and windows, 

 hammering in the vicinity, a current of cold air, a flash of light, 

 moving the patient in the stall, attempts at mastication, simple 

 handling, administering medicine, or sudden jerking of the head 

 upward promptly brings on a paroxysm of spasm. Pushing the 

 head suddenly upward or jerking on the halter, is often resorted 

 to as a means of diagnosis, the sudden resulting rigidity of the 

 muscles generally, the rolling of the eye, its retraction toward the 

 depth of the orbit and the protrusion of the membrana nictitans 

 over one-half, one-third or more of the cornea, bringing out the 

 diagnostic symptoms in a striking manner. In very severe cases 

 the head may be drawn upward and backward almost to above 

 the loins (Henry), or one or more of the dorsal or lumbar verte- 

 brae may be broken or crushed (Zundel). A sudden loud noise 

 will sometimes cause the exhausted animal to drop to the ground. 



Perspiration is not uncommon. Breathing is usually accel- 

 erated, the encrease being in ratio with the violence of the spasms. 

 Pulse and temperature are usually normal at first and may be in 

 slight cases throughout. Even in severe cases the pulse does not 

 rise so much as the respiration. In violent and fatal cases 

 the temperature often rises excessively before death (104" to 

 110° F.). 



When the jaws are not absolutely closed, the tongue is often 

 wounded by the teeth, and, in any case is covered by a tenacious 

 mucus, which may hang in strings from the lips. If the jaws 

 are still movable, mastication is still carried on, but slowly, pain- 

 fully and imperfectly, and deglutition is more or less difficult. 

 Young animals are unable to suck. 



Symptoms in the horse. When the symptoms are fully devel- 

 oped, they are very characteristic. The neck is raised, often con- 

 cave along its upper border, the nose raised and protruded more 

 or less, the nostrils widely expanded, the eyes sunken, fixed and 

 anxious, with dilated pupils and protrusion of the haw outward 

 and upward from the inner canthus, the ears are pricked, rigid. 



