Farm Animals and Principles of Feeding 275 



in the United States are raised in the corn belt. But 

 corn does not furnish enough mineral matter, and to 

 supply this lack ashes should be kept in a feed rack. 

 To the ashes are often added other minerals : air-slaked 

 lime, salt, sulfur, and copperas. Several kinds of 

 grain, to give variety, are better for feeding than any 

 one grain alone. 



When young are expected, the mother should be sepa- The care 

 rated from the other hogs, for they sometimes kill the * 

 little pigs. The pen in which the young are kept should 

 have a guard rail within the wall and near the ground, 

 so that the mother cannot crush the little pigs against 



U. S. D. A. 



FIG. 221. Inoculation prevents cholera in a hog (makes 

 the hcg immune) as vaccination prevents smallpox in a 

 human being. Immunity against cholera lasts only a 

 few weeks, and for this reason hogs should be inoculated 

 whenever there is danger of the disease. 



