SWINE MANAGEMENT. 



29 



Fig. 12— Sanitary hog pens and feed lots are essential to successful hog raising. (Photograph by courtesy 

 of District of Columbia Workhouse Farm, Occoquan, Va.) 



They may be carried in a multitude of ways — ^by the hogs themselves, 

 on the clothing of persons, on vehicles, in feed, by birds, dogs, and 

 other animals, or by streams. The breeding or feed of a hog can not 

 cause either disease, although bad methods may so weaken the con- 

 stitution and vitality that the animal becomes ipore susceptible to 

 them than would otherwise be the case. Since these diseases can 

 only arise from the presence of their specific causative agents, it can 

 readily be seen that dentition and the presence of supernumerary 

 teeth or black tusks can not, as has been suggested by many, play 

 any part in their development. A second fact to be borne in mind 

 is that diseases caused by germs may be best prevented or controlled 

 by thorough disinfection and scrupulous cleanliness. 



Tuberculosis is rapidly increasing among hogs in the United States, 

 and every owner of swine should be on his guard against the intro- 

 duction of this serious malady upon his premises. Unlike hog cholera 

 this disease is insidious in its attack and slow in its development, so 

 that it may be present for months in a herd without exciting the least 

 suspicion of the owner, and will be revealed to him only at the time 

 of slaughter. Until recent years tuberculosis has been looked upon 

 as of imconamon occurrence and only of importance from a meat- 

 inspection standpoint ; but to-day it must be recognized as a serious 

 menace to the owner of hogs, and especially to the one who allows 

 his hogs to run with cattle that have not been proved to be free of 

 tuberculosis, or who feeds them upon nonsterilized products as part 



