EEPOKT OF THE BUREAU OF ANIMAL INDUSTRY. 155 



on "hog cholera. We shall confine ourselves in this place to a descrip- 

 tion of their employment. 



Disinfectants are substances which, in solutions of a certain 

 strength, are capable of destroying disease germs. Consequently 

 they should be applied wherever the disease germs are supposed to 

 be. In case of hog cholera they are attached to the sides and floor- 

 ings of pens, and to the various utensils used in cleaning them. 

 They are mixed with the earth over which the diseased animals have 

 run, or in the water which they have frequented. In the report of 

 the Department for 1886 the use of mercuric chloride (corrosive sub- 

 limate) was recommended, as it is a powerful disinfectant. Since 

 that time other disinfectants have been tested which are equally cheap 

 and easily procurable. The main objection to mercuric chloride is 

 its extremely poisonous character, which makes it undesirable to 

 deal with it. This substance has therefore been thrown out, in spite 

 of its powerful germicide properties, from our list of available disin- 

 fectants. 



The wood-work of pens, fences, flooring, etc., is best disinfected by 

 using upon it, with a broom, solution No. 2, until thoroughly wet. 

 In preparing this solution it should be stated that the mixing must 

 be done in a glass bottle or jar, and the mixture poured slowly into 

 the proper amount of water in a wooden pail. This should be rinsed 

 out after using to prevent the acid from slowly destroying the iron 

 hoops. 



Whenever No. 2 is not obtainable No. 3 may be used in its place, 

 which seems to be equally efficient. 



Lime is a very efficient disinfectant for hog cholera. Experiments 

 have shown that a solution containing only .02 per cent, will destroy 

 the bacteria. When much organic matter is present, as much as .5 

 per cent, to 1 per cent, may be necessary. We recommend the pro- 

 portions given under No. 1, which give from ten to twenty times the 

 strength required. The resulting liquid is not too thick to be easily 

 manipulated. It may be used on wood- work as a whitewash, and it 

 may oe spread as a thin layer over the soil which has been infected. 



The 2 per cent, solution of pure carbolic acid should be used when- 

 ever No. 2 may act injuriously by virtue of the sulphuric acid which 

 it contains. 



In general we recommend the use of No. 2 or No. 3 as often as it 

 may seem necessary. It should be dashed upon the infected pens, 

 troughs, tools, and over the infected soil. When there is no objec- 

 tion to lime this may be used on the soil, as it is equally efficient. 

 The discharges should be covered with powdered or slaked lime, and 

 this should be thrown in abundance into pools, or wherever water 

 stagnates. In the case of troughs for feed, iron tools, etc., which are 

 liable to injury, the disinfectant should be washed away with boiling 

 water if this is at hand. Boiling yater will destroy hog cholera 

 germs by simple contact, and the disinfection will thus be made more 

 complete. Shoes may be disinfected by rubbing them with solution 

 No. 4. 



It must be carefully borne in mind that no manure from sick pigs 

 should be removed until it has been treated with disinfectants. The 

 cleaning must be done after disinfection and not before, to prevent 

 the dissemination of living virus. 



The agency of mice and rats in transporting virus will depend upon 

 the promptness and thoroughness with which disinfection and cleanli- 

 ness are practiced. Mice are more dangerous than rats, in so far as 



