34 8 IOWA DEPARTMENT OF AGRICULTURE 



He had a lot of fall pigs which showed the disease quite severely. I se- 

 lected fifty-one head for the experiment which, as near as I could tell, 

 were in fair condition. It was impossible to tell, without taking the 

 temperature of each animal, whether they were all well hut fifty-one of 

 the better ones were selected. Then to show as nearly as possible what 

 might be the result we divided the fifty-one into three lots. Two-thirds 

 were treated and one-third were left untreated, making thirty-four which 

 were injected with the serum and seventeen left untreated. They were 

 then turned into a clover field where they had principally green clover 

 for feed with access to a little corn in the field. Of the thirty-four treated 

 with serum six died. Of the seventeen left untreated fifteen died. The 

 other two survived. The disease had obtained a good start in this herd 

 and the fact that nearly all the checks died shows that most of the herd 

 would have died if they had not been treated. 



In another herd containing thirty shoats and three old sows with lit- 

 ters, which we supposed was an entirely well herd, we intended to treat 

 only the older hogs and simply leave the suckling pigs for checks to 

 see if the disease got on the farm. However, one of the shoats was taken 

 sick, and a few days later died. One of the old hogs also died. Of the 

 twenty-nine injected twenty-eight survived and of the three old hogs two 

 survived. The suckling pigs all died. That was an exposed herd, as 

 shown by results, although disease was not apparent on the day of treat- 

 ing the herd. 



One of the most interesting herds we had was herd No. 6. I found one 

 of the hogs somewhat dumpy. The next day when I went back to the 

 farm and found the hog still worse but not showing sufficient symptoms 

 so one could diagnose hog cholera. I treated sixty-seven shoats for this 

 man, all spring shoats weighing from fifty to seventy-five or eighty 

 pounds. Twelve of the bunch were left untreated as checks. You under- 

 stand that if we had treated the whole herd it might have been hard 

 to find out if they had the disease. In these experiments where it was 

 necessary to have the checks of course the farmers regretted losing the 

 checks but in most cases were well satisfied to save a large per cent. 

 Now that you can obtain the serum it is not necessary to do this. In 

 herd No. 6 of the sixty-seven treated si'xty-four survived. Of the twelve 

 animals untreated eight died, two others recovered in a very poor, 

 stunted condition, and the other two survived in fairly good condition. 

 So we really saved two of the checks while out' of sixty-seven we saved 

 sixty-four. 



Herd No. 9 was very similar. In this herd on day of examination two 

 shoats in the lot showed some indication of the disease, were a little 

 droopy and did not come up to eat with the others. There were thirty-five 

 shoats in this lot. Thirty of them were injected, including the two sick 

 ones. Five were left as checks. In addition two old sows were given 

 treatment. The five check animals died. The two animals sick on day 

 of treatment also died. The rest of the herd remained well. That was 

 a most interesting result, showing that the well animals treated in the 

 herd survived while the sick ones did not live. 



