SUMMARY 301 



Remember that you also may be the cause of carrying infection 

 into your feed lots, and never leave a strange hog lot and go directly 

 to your own without first thoroughly washing all mud, manure, and 

 other dirt off your shoes, preferably with some good disinfectant 

 solution, such as liquor cresolis compound. 



(16) Bringing In New Hogs. — ^This must always be regarded as 

 a dangerous undertaking. We can never be sure that the new ani- 

 mals so brought in are free from cholera unless we have positive 

 knowledge that they have been properly immunized by the double 

 serum virus method of treatment. Even animals which have 

 passed through an attack of the disease are not always safe to add 

 to our herds, as they may still have a hidden type of the infection — 

 in other words, they may belong to the class of what we know as 

 "cholera carriers." 



The only real certain means of preventing entrance of cholera by 

 this means is the establishment of a proper quarantine on the ani- 

 mals for at least thirty days after their arrival on your premises 

 before adding them to your regular herd. We know that the incu- 

 bation period of cholera is usually less than two weeks, and very 

 seldom as long as four weeks, so that by quarantine for a period 

 of thirty days we have insured our herd against all danger from this 

 direction. 



On shipments of any class of animals which may come into the 

 United States from abroad the United States Government requires 

 quarantine at port of entry for a reasonable length of time. By this 

 means introduction of many severe animal diseases which are 

 present in foreign countries has been prevented, notably so an out- 

 break of surra, which came very near being admitted into the 

 country in 1906 with an importation of sacred cattle from India. 

 These animals had been thoroughly tested for presence of the dis- 

 ease before the shipment from India, and had been declared free 

 from infection. However, while in quarantine at New York harbor 

 it was found that several of the animals were really carriers of 

 surra infection, and only by prompt measures was the introduction 

 of this disease into the United States prevented. 



Home quarantine of newly purchased animals can be very 

 easily and very cheaply carried out, and it is a most important safe- 

 guard against severe losses in your herd. 



