206 HOG CHOLERA 



urine and f eces contain the virus usually in forty- 

 eight hours, and the secretions of the eyes and 

 nose become infectious by the third day follow- 

 ing infection: therefore these experiments show 

 that infected pigs are capable of transmitting 

 the disease before they themselves show any visi- 

 ble illness." l 



Thus the blood and therefore the meat of a hog 

 infected to-day will to-morrow contain hog cholera 

 virus sufficient to infect others, but there will be 

 neither symptoms, temperature readings nor le- 

 sions to cause its condemnation. The same will 

 be true on the second, third and fourth days fol- 

 lowing infection, but from that time on we may at 

 any time expect developments that would cause 

 condemnation. These may, though, be delayed 

 several days longer. There is a time, at least 

 three days on an average, in the lives of practi- 

 cally all hogs affected with acute hog cholera when 

 they will pass inspection and when bits of pork 

 from their carcasses will infect other swine to 

 which they are fed. This interval varies from 

 one or two to several days, and is measured, 

 roughly, by the time required, after the first 

 twenty-four hours following infection, for the 

 temperature to rise to 106 F., or for conclusive 

 symptoms or extensive cholera lesions to appear. 



1 Keport of the chief of the U. S. Bureau of Animal Industry 

 for the year ending June 30, 1917. 



