TETANUS. 135 



latter form may be the result of irritation caused by para- 

 sites, as worms, etc., in the intestines, or may be the result 

 of gastric irritation of various kinds. Often a very simple 

 injury will produce tetanus. Hence, a case of tetanus may be 

 due to an injury so trivial, or a wound so slight, that it cannot 

 be discovered. Such a case would, of course, be called 'idio- 

 pathic,' while in reality it would be a case of ' traumatic tetanus. ' 



The disease is far more common in hot than in cold 

 climates, and more so where there are extremes of heat 

 and cold. In certain localities animals will suffer from 

 tetanus resulting from the most trivial wounds ; indeed, 

 to such an extent does it i3revail in some places, that it 

 might almost be described as enzootic. Tetanus is more 

 likely to occur as a result of punctured wounds than of any 

 other kind of wound, and it manifests itself, as a rule, about 

 the time the Avound is healing, or is nearly well. It occa- 

 sionally supervenes on castration, and about the ninth or 

 tenth day, when the wound is healing nicely, is when the 

 disease makes its appearance. The person who performed 

 the operation is usually blamed, but unjustly however, as 

 tetanus will often follow this operation, no matter how it 

 has been performed, whether properly or otherwise. After 

 castration, the animal should not be allowed to take cold, or 

 to stand in cold w^ater or draughts. If he is exposed in this 

 way, he has a pretty good chance of suffering from tetanus. 

 Percivall mentions that out of twenty-four horses castrated 

 in one day, and exposed in the way above mentioned, six- 

 teen of them contracted the disease. Tetanus is one of the 

 most fatal diseases with which the veterinarian has to deal. 



Post-mortem. — The muscles, after death, have a peculiarly 

 soft, flabby feeling. The sheaths oC the nerves present well- 

 marked traces of congestion. More or less effusion is 

 observable in connection with the brain and spinal cord, and 

 also with some of the large nerves. 



