ooo.oo. In addition to the State plants there are no less than seventy- 

 six private or commercial plants manufacturing and distributing serum 

 in the United States. 



Serum Production. 



To produce potent anti-hog-cholera serum in accordance with the 

 Dorset-Niles method it is necessary to start with an immune hog. To 

 secure this "immune" it is necessary to get a hog which has been in- 

 jected with serum and virus at least twenty-one days before, or select 

 a hog which has recovered from the disease itself, as it is a well-known 

 fact that when a hog recovers from an attack of cholera he is forever 

 thereafter "immune." 



After securing the immune it is necessary to obtain "virus" (blood 

 from a hog on the verge of death from cholera. (See Figs. 17, 1 8 and 

 19 for injection into the ear vein of this immune.) The amount of 

 virus necessary to hyperimmune an immune weighing 300 pounds 

 would be 1500 c.c. (approximately three pints). This virus is given 

 intravenously, the ear vein being used. (See Figs. 21 and 22.) After 

 an interval of fourteen days the hyperimmune is bled from the tail. 

 (See Figs 23 and 24.) The usual amount taken should not exceed 

 the amount of "virus" given, which would mean 1500 c.c. from a 300- 

 pound hog. After an interval of seven days the hyperimmune is again 

 bled from the tail. At the end of the next week this hyperimmune is 

 carried to the abattoir for slaughter and final bleeding. (See Fig. 26.) 



After the blood from the hyperimmune is secured it is defibrinated 

 by specially-constructed machinery in the serum laboratory of the 

 plant. (See Fig. 25.) To this defibrinated blood one-half of one 

 per cent carbolic acid is added, which acts as a preservative. 



Anti-Hog-Cholera Serum. 



Anti-hog-cholera serum is the defibrinated blood (liquid portion 

 of the blood) of a healthy hyperimmune hog. It is impossible for 

 this serum to cause hog cholera, because it is charged with "anti- 

 bodies" which possess the property of being antagonistic to the hog 

 cholera infection, and will protect or immunize any healthy hog against 

 this disease. 



Fake "Serums" and "Vaccines." 



With the advent of the Dorset-Niles Anti-Hog-Cholera Serum a 

 few years ago the most deadly of all swine diseases was doomed to 

 ultimate eradication from the American continent. It is a well-known 



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