55 



• 



about four months. They were perfectly healthy, in fine condition 

 and free from parasites. They had never been treated in any way. 

 Two came from a herd on Oahu and one from Hawaii and the 

 herds from which they came had never been exposed to cholera 

 or treated with vaccines of any description. The three animals 

 were therefore considered fit subjects for the experiment. 



On Febraury 19, two of the above hogs received intramuscular 

 injections of the filtered blood as follows : 



Hog No. 1 6 mil. 

 Hog No. 2 10 mil. 



Hog No. 3 was not injected but was left in contact with the 

 others. During the experiment the animals were fed, watered 

 and otherwise cared for in the same manner as before the experi- 

 ment. 



In experiments of this nature 2 mil. is usually considered suffi- 

 cient. A much larger dose was used in this case so as to leave 

 no doubt that a sufficient amount of the virus entered the system 

 to produce results. 



Symptoms of cholera should have appeared in from eight to 

 twenty days after injection of the filtrate. Six weeks have now 

 passed and the animals are in fine condition having gained at 

 least a hundred pounds in weight. This shows conclusively that 

 as far as that particular sample of blood is concerned the virus 

 of hog cholera was not present. 



Of course, far reaching conclusions should not be based on one 

 experiment. A number of such experiments will have to be made 

 before it can be definitely stated that hog cholera does not exist 

 in this Territory, but as far as we have gone there is no evidence 

 to show that the introduction of hog cholera virus is warranted. 



When it is definitely ascertained that hog cholera is present the 

 necessary methods for its control and eradication will be insti- 

 tuted. There is a certain amount of danger connected with the 

 indiscriminate use of hog cholera virus which should not be re- 

 garded lightly. To quote from the 1920 report of the State 

 Veterinarian of California, "Occasionally so-called 'breaks' occur 

 after hog cholera vaccination with the result that the owner will 

 sometimes question the reliability of the vaccination. As a matter 

 of fact 'breaks' in most cases, can be attributed to the fact that the 

 hogs were sufifering with a mixed infection, and hog cholera, if 

 present, was not the primary cause. A correct diagnosis is all 

 important in the treatment of sick hogs. The use of hog cholera 

 virus and serum when no cholera exists means a waste of much 

 time and expensive materials and will do no good when the loss is 

 due to other causes." 



Quoting from Circular 176 of the Agricultural Experiment 

 Station, University of California : 



"The only protective treatment that will give satisfactory re- 



