514 CEREBRO-SPINAL MENINGITIS 



CERKBRO-SPINAIv MENINGITIS IN HORSES. 



Synonyms. Staggers ; crazy disease ; forage poisoning ; 

 acute epizootic leucoencephalitis. 



§ 399. Characterization. This is a disease that seems 

 to be infectious in its nature, exhibiting symptoms referable to 

 a disturbance in the central nervous system. It is called 

 epizootic cerebro-spinal meningitis because it often attacks a 

 number of animals in the same locality. It often occurs in 

 sporadic cases. Although the literature contains numerous 

 accounts of its seemingly contagious nature, an analysis of the 

 facts fails to bring forth conclusive evidence that it is ever 

 transmitted directly from one horse to another. In nearly if 

 not all outbreaks, the animals affected have been subjected to 

 like conditions of life. This disease is, at the present time, 

 peculiar in that its cause is not known, that obvious tissue 

 changes are usually absent, and that it has a very high 

 mortality. 



§ 400. Etiology. The cause has been attributed to a 

 •great variety of conditions, such as fermented food, forage 

 laden with fungi or toxic moulds, various unsanitary con- 

 'ditions and possibly other ill-defined agencies. It seems to be 

 true that in most outbreaks all of the animals that suffer have 

 :had at least some one thing in common either in surroundings, 

 :food or management. The bacteriological and other examina- 

 ■tions which have been made to determine the cause have not 

 resulted in finding a specific agent. Micrococci and various 

 bacilli have been found associated with the disease. The 

 writer has had an opportunity of making a careful examina- 

 lion of animals in two outbreaks. In one of them all inocu- 

 lated media and histological examinations gave negative 

 results, in the other pure cultures of a colon bacillus were ob- 

 tained from the brain. No specific organism, therefore, is 

 charged with its production. No virus has been isolated that 

 is capable of producing it. The nature of the affection sug- 

 _gests a poison rather than a specific virus. 



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