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WHEN CHOLERA APPEARS. 



When cholera appears in your neighborhood it is best to confine your 

 dog and request your neighbor to do the same. 



Should cholera appear in your herd, it is advisable to treat all sus- 

 ceptible hogs. Destroy and bury, or burn, all hopelessly sick animals. 

 Confine all treated animals to a limited range. Collect and spread all manure 

 in field, so that it may readily be reached by sunlight. Burn all litter, loose 

 boards, and old hog troughs which may harbor hog cholera germs. After 

 removing all rubbish, spray the walls and floors with a good disinfectant. 

 Often a false sense of security is obtained by the owner after an inefficient 

 application of a disinfectant. To secure the best results, all objects which 

 have become contaminated with the excretions of sick hogs must be thor- 

 oughly saturated with the disinfectant. Unless this is done, ill results may 

 follow when new hogs are placed in these inclosures. When hog houses 

 will permit, they should be turned so as to expose their interior to the 

 action of sunlight. 



Hog wallows and cesspools should be either drained, filled in, or fenced 

 off. Runways beneath buildings should be closed to prevent hogs entering. 



Now I recall a few years ago one place where under an old barn hogs 

 had died fifteen years before, and there came a storm and the men tore 

 the boards off from underneath this old barn and let some hogs in there, 

 and in the course of time, the required time, they developed hog cholera. 

 Undoubtedly this disease had stayed under that old barn for fifteen years. 

 Old straw stacks should be removed and scattered over a field or burned. 



Many drugs and compounds have been placed on the market, for which 

 great claims were made as preventives or cures of this disease. Without 

 exception, anti-hog cholera serum is the only known agent capable of pro- 

 tecting animals against hog cholera. The method of producing this serum 

 as devised by the United States Bureau of Animal Industry can be sum- 

 marized as follows: 



THE INOCULATION TREATMENT. 



Hogs that have been rendered immune to cholera by the inoculation of 

 serum and virus are employed in the production of anti-hog cholera serum. 

 These immune animals are injected with a large quantity of blood obtained 

 from cholera sick hogs. The injection of a very small quantity of this cholera 

 blood would produce disease in any susceptible hog, but with the immune 

 animal even the injection of large amounts of this blood produces no ill 

 results. Ten days after the immune hog has been injected with the cholera 

 blood his own blood will contain a large amount of substances which will 

 protect against this disease. The protective substances or anti-bodies are 

 so concentrated that comparatively small amounts of the blood when 

 injected into other hogs will protect them against cholera. 



The question arises, "How are we to, know that this blood does 

 contain sufficient amount of anti-bodies to protect other animals?" Since no 

 animals other than swine are susceptible to this disease, it becomes necessary 

 to inject healthy pigs with cholera blood and at the same time administer a 

 dose of the serum to be tested. Large amounts of blood obtained from many 

 different injected immune hogs are mixed and a sample taken from this 

 mixture is used for the test, so that by one test the value of many quarts 

 of serum can be shown. The most suitable animals for test purposes are 

 pigs weighing from 45 to 90 pounds. Seven healthy pigs are used for each 

 test. Each of the seven pigs is injected with two cubic centimeters of the 

 blood from cholera sick hogs. Of these pigs, five receive twenty cubic centi- 

 meters of the blood from immune hogs; two of the pigs receive no serum; 

 or, in other words, have nothing but their natural resistance to withstand 

 the attack of the disease. If the serum possesses the proper protective 

 power, all five of the test pigs will remain healthy. On the other hand, 

 those receiving the cholera blood but no serum will take the disease and 

 die. It is necessary that the two pigs receiving no serum sicken not earlier 



