TETANUS OF THE HORSE 47 



Tetanus does not spread from one horse to another by contagion or 

 infection, but it can be transmitted by inoculation with the pus, or by a 

 portion of the damaged structure of a wound, and there is a certain amount 

 of risk incurred by the persons who dress such wounds if they happen to 

 have any abrasions of the skin of the hands. 



It is usual to classify the disease according to the part of the body 

 which is most affected, and in accordance also with the rapidity of its 

 progress. Thus there is acute and chronic tetanus. The terms which 

 are sometimes in use — rheumatismal tetanus as the result of cold, and toxic 



tetanus due to poisoning by strychnine — do not properly come under 

 consideration in connection with the true contagious disease. When the 

 tetanic spasm affects the muscles of the head and neck the condition is 

 described as trismus. When the spasm affects the muscles of the back, 

 and jDulls the head backwards, the term opisthotonos is applied; in the 

 opposite condition the word emprosthotonos was used to indicate the bend- 

 ing of the body forward, and in cases where the spasm affected one side 

 of the body, causing it to curve to that side, the condition was defined as 

 pleurosthotonos. All these states are recognized in different phases of the 

 disease in the human subject, but they are rarely met with in the horse, 

 with the single exception of the first, described as trismus, which is the 

 most common form. 



Symptoms of Tetanus. — At the commencement of the disease, from 

 ten to sixteen days after the introduction of the infectious material, some 



