I02 



Journal of Agricultural Research 



Vol. XIII. No. 2 



TRANSMISSION OF HOG CHOLERA BY PIGS 



The fact that the blood and excreta and the eye secretions of hogs 

 sick of cholera contain the virus of the disease is already well estab- 

 lished. However, comparatively little systematic work has been done 

 to ascertain whether the virus is discharged from the body only at cer- 

 tain stages or whether this occurs continuously throughout the course 

 of the disease. Experiments on this point have been carried out in two 

 groups. In the first, the pathogenic power of the blood, urine, feces, 

 eye secretions, and nose secretions from hogs in different stages of the 

 disease was determined (i) by the inoculation of susceptible pigs, (2) by 

 feeding susceptible pigs with the secretions and excreta, and (3) by 

 scattering the secretions and excreta in pens containing susceptible pigs. 

 In the second group of experiments the contagiousness of the disease at 

 different stages was determined by placing susceptible pigs in contact 

 with those that were infected. 



INFECTIOUSNESS OF THE BLOOD, EXCRETA, AND SECRETIONS OF CHOLERA- 

 INFECTED PIGS 



Experiment I. — Pig 1032X was injected subcutaneously with 5 c. c. of 

 virus blood on October 11, 191 6. This pig showed a rise of temperature 

 on the fourth day, and the first visible symptoms were observed on the 

 fifth day. The animal died on the tenth day, exhibiting well-marked 

 hemorrhagic lesions at autopsy. 



The clinical record of pig 1032X is given in Table I. 



a Blood, excreta, and secretions were tested on these dates. 



On the first, second, third, fifth, and ninth days after injection the 

 blood, urine, and feces, and the eye and nose secretions were collected 

 and tested on susceptible pigs. Two pigs were injected with each 

 material on each date, making a total of 10 pigs injected on each day. 



The blood was obtained by bleeding from the tail. The urine and 

 feces were collected in sterile bottles. The eye and nose secretions were 



