THE CARE OF SWINE 435 



are made immune. As cholera is highly contagious, great 

 care should be used to prevent any exposure of healthy pigs. 

 It is even unsafe for a person working with healthy pigs to 

 visit a diseased herd, on account of the danger of conveying 

 the disease by means of his shoes. Every farm on which 

 cholera prevails should have a sign at the entrance to the 

 farm, stating that cholera is in the herd. 



Tuberculosis among swine is common, especially in herds 

 fed skim milk or buttermilk that has not been pasteurized. 

 This disease is most common, therefore, among pigs fed in 

 dairy districts. When fed in connection with healthy cattle, 

 pastured on forage crops, and given concentrates, tuber- 

 culosis is not a common disease among swine. The best 

 method of preventing it is to feed no milk excepting with the 

 certainty that it comes from a healthy source and to keep a 

 herd of cattle known to be free from this disease. Pigs 

 valued at millions of dollars are condemned at packing houses 

 each year on account of having tuberculosis. The affected 

 pig can not be cured. 



Removing the tusks of the boar often becomes a neces- 

 sity. A mature boar, with long sharp tusks, is a source of 

 danger, as a person may be seriously injured by them. They 

 are, therefore, usually removed in well managed herds. The 

 following method is recommended by Prof. G. E. Day:* 



"The boar is first made fast to a post by means of a rope noosed 

 about his upper jaw back of the upper tusks. Then one man takes a 

 crowbar and another a sharp chisel and a hammer. The sharp edge of 

 the crowbar is placed against the tusk near its base, and held firnily in 

 position, and the edge of the cold chisel is placed on the opposite side of 

 the tusk directly across from, and even with, the edge of the crowbar. 

 A sharp blow with the hammer on the cold chisel does the job." 



Marking the litters of pigs is very necessary in pure-bred 



herds. The young pigs may be given ear tags, when 3 or 4 



weeks old, as indicated on page 54, but these tags often get 



torn from the ears of pigs, and the tag is then lost. Numbers 



may be easily tattooed in the ears of pigs of the white breeds. 



as is commonly done in England. In the United States 



*Productive Swine Husbandry, 1915. 



