496 DISEASES OF SWINE 



c.c. of virulent blood. Thirteen spring barrows were left untreated 

 to serve as checks. 



The final outcome of the experiment in this herd is, indeed, most 

 interesting. The treated gilts and the untreated barrows remained 

 in the same feed lot for nearly a month, and none of them showed 

 any signs of disease. The last week in November the owner of the 

 herd purchased a young boar from the farm on which Herd Number 

 Thirty-five of this series was located. This boar had passed through 

 a mild attack of cholera, but was apparently entirely well. He was 

 carefully dipped in a disinfectant solution and placed in a pen im- 

 mediately adjoining the untreated checks. Eight days after his 

 arrival on the premises one of the check shoats was sick. This 

 animal showed the usual symptoms of an attack of cholera — loss of 

 appetite, dulness, inactivity, muscular weakness, and staggering 

 gait. On December 7th this sick shoat died and the body was 

 opened up to make sure of the cause of death. The findings were 

 those commonly met with in hog-cholera. The spleen was swollen 

 and dark in color, the liver was congested and enlarged, the kidneys 

 swollen, softened, and spotted with the typical dark-red dots. In 

 a few days 2 more of the checks were noted to be off feed, and the 

 owner, fearing that he would lose the entire bunch of barrows, sold 

 the remaining healthy 10 for immediate slaughter. The 2 that 

 were sick at this time soon died. 



During the entire time the 35 treated shoats were right in the 

 same pen with the sick animals, and not one of them showed 

 the least evidence of being sick. There can be no question 

 but what they were repeatedly exposed to the infectious dis- 

 charges from the sick shoats that died, but the protection given 

 by the double treatment was so complete as to entirely safeguard 

 them. 



On December 4th, of this same year, the owner of the herd held 

 a public sale, at which he disposed of a number of these treated 

 animals. He advertised them as "vaccinated" hogs, and on the 

 day of sale they were guaranteed against taking hog-cholera for a 

 period of two months after removal from the premises. Many of 

 these treated hogs were purchased by farmers whose herds had been 

 entirely cleaned out by cholera during the past fall. They were 

 taken to these infected farms and placed in the disease-bearing 



