114 Missouri Agricultural Report. 



cholera. The infected blood used on this lot was not drawn under 

 the most favorable condition, and there is a possibility that other 

 infection besides the hog cholera virus was also present. The ob- 

 ject of the inoculations in this lot was to compare the protective 

 value of clear serum and corpuscles. 



In lot 6, inoculated on the same day with the same serum, were 

 seven Duroc boars. Two of these were inoculated with 40 c. c. of 

 the serum, four received 30 c. c. ; the fifth animal, a small one, was 

 quite sick at the time of the inoculation. This one received only 

 a small dose as the quantity of the serum available was not suffi- 

 cient to give a larger dose. With this lot three hogs were not in- 

 oculated: One, a Berkshire boar, was sick at the time; the other 

 two, a Duroc boar and a Berkshire barrow, were not showing any 

 signs of illness. All the sick animals mentioned and the two ap- 

 parently healthy animals, not inoculated, died some time later; 

 while only one of the six Duroc boars which appeared to be healthy 

 at the time of the inoculation succumbed to the disease. As these 

 animals were all on infected grounds and a part of them had the 

 disease, the vaccinated animals were not injected with virulent 

 blood. 



In lot 7 were nine animals. Five Berkshire sows were inocu- 

 lated with 40 c. c. of the serum, one Berkshire sow 30 c. c, one 

 Berkshire gilt 20 c. c, one Poland gilt 40 c. c, one Duroc gilt 20 

 c. c. As these animals had an opportunity for natural infection, 

 they were not inoculated with virulent blood. ■ None of this lot 

 died. 



In regard to the technique of collecting the serum and inocu- 

 lating it into the hogs, the following description and the accom- 

 panying illustrations will help to make the matter clear: 



After the supply animal is made "hyper-immune," the collec- 

 tion of the blood is made from the tail on account of the difficulty 

 of tapping the deep-seated jugular vein. The animal is cleaned 

 well and tied firmly to an operating table, made convenient for this 

 work. To prevent contamination of the serum, the tail of the ani- 

 mal is made thoroughly clean by shaving off the hair and applying 

 antiseptics. A bit of the tail is then cut off and the blood collected 

 from the bleeding end in a sterilized vessel, the mouth of which is 

 carefully protected by a sterile towel. A cover is also drawn over 

 the pig in such a manner as to prevent any contamination from the 

 hair and skin. After the blood has been collected the clot is re- 

 moved and the blood that remains is preserved by adding a small 

 quantity of carbolic acid (*/•> per cent), or the blood may be used 



