NATURE OF THE DISEASE. 89 



cliate inducing factor. Still, altliougli the fever does largely- 

 manifest itself in animals during the period of life when the 

 inception of teeth is being actively carried on, there does not 

 seem any sufficient reason why we ought to regard this act as 

 an active developing agent in the production of strangles. 



The more rational views to take of its causes and modes of 

 propagation seem to be those already noticed when remarking 

 on the question of its contagious or non-contagious character. 



1. To regard it as resulting from a species of zymosis 

 induced by the absorption into and addition to the circulating- 

 fluids and blood of some peculiar noxious agents, the product 

 of chemical changes on organic matter extrinsic to the animal, 

 which on entering the circulation either of themselves or in 

 conjunction with other deleterious materials which have been 

 retained unnaturally in the body, and which are rendered pos- 

 sible of augmentation, are capable of producing certain specific 

 changes in the blood, these changes exhibiting themselves in 

 the local eruption and suppurative action. 



The highly susceptible state of the system of young and 

 growing horses, those in which we observe this disease most 

 extensively, together with the operation of those causes which 

 induce imperfect elimination of waste and degraded tissue, 

 and the conditions with which young and fresh animals are so 

 often surrounded, seem to point to this infringement of the 

 laws of hygiene and dietetics as a very probable source of the 

 origin of strangles. 



2. To regard strangles as capable of being propagated by 

 contagion. That any disease shall be capable of propagation 

 by the contact of the diseased with the healthy, it is not abso- 

 lutely needful that every case shall show the same decided 

 character or tendency to spread even when the material for its 

 dissemination is within reach. We are well aware, as already 

 stated, that many cases and outbreaks of strangles are most 

 satisfactorily accounted for apart from the question of con- 

 tagion ; still we may not shut our eyes to many facts which 

 point, as the only satisfactory explanation of its origin and 

 propagation, to the inherent contagious character of the 

 disease : to the fact that there is given off from the actually 

 suffering animal some organic material, whether active 

 germinal matter capable of inducing active special changes 



