THE DISEASES OF CATTLE. 343 



thirty-six. All animals are subject to it, but the herbivora 

 more so than others. It is either epizootic or enzootic ; the 

 first is the most destructive." 



I now consider the point settled regarding the nature of the 

 disease ; viz., it is an epizootic or enzootic affection, and, of 

 course, is subject to the same laws which govern diseases of 

 this type. This will explain the otherwise unaccountable vari- 

 ations which are observed in the symptoms of the affection 

 when prevailing in different localities, and it also enables us to 

 account for the great losses which Messrs. Shortfeed and Over- 

 feed are continually encountering. The fact is, all overfed 

 animals may be ranked as gluttons, and all half-starved an- 

 imals furnish a savory morsel for the great epizootic patholog- 

 ical glutton, which, like the epidemic one that, hovering around 

 the city of New Orleans, a few years ago, destroyed several 

 thousands of its inhabitants ere it touched a single sober citizen. 



When this disease rages in a single locality, it is supposed to 

 have a spontaneous origin. Then the term enzootic is applied to 

 it ; and if it prevail among the cattle of an extensive region, 

 then it is called epizootic. 



Causes of Blqck Leg, etc. — The causes of this affection are 

 as obscure as those of cholera, influenza, potato rot, etc. They 

 seem to appear independent of local causes, occur at uncertain 

 intervals, prevail for indefinite periods, and run their course in 

 a sliort space of time. It is supposed by some persons that a 

 disease of this character and nature is propagated by contagion 

 or infection. How far it is engendered in these ways, I am not 

 prepared to decide. There must, however, have been a time 

 when the disease did not exist, but must have arisen from a 

 concurrence of natural caus"es ; and if these were adequate to 

 its production at an anterior period, they must be so at the 

 present time. I shall, therefore, abandon all further specula- 

 tion in this direction as unprofitable, for there is evidently no 

 direct cause, but various are the predisposing, exciting, indirect, 

 and morbid causes. The only way that I know of to prevent 

 tliis malady is to keep the cattle in a physiological condition, 

 by paying proper attention to breeding, feeding, rearing, and 



