METHODS OF USING ANTI-HOG-CHOLERA SEBUM 131 



which operates easily and requires uniform pres- 

 sure on the plunger should always be selected. 



Cleaning and disinfecting the site of injection 

 are processes frequently neglected, because the 

 hog is proverbially difficult to infect. He can be 

 infected though, as some have found to their sor- 

 row. If hogs are at pasture or in clean, dry, well- 

 bedded pens, cleaning is not difficult. Some sim- 

 ply paint the skin with tincture of iodin, and this 

 answers well when the site of injection is both 

 dry and clean, but tincture of iodin is not suitable 

 for use on wet surfaces. We have found nothing 

 better than a good coal-tar disinfectant applied 

 with a stiff scrub-brush, for this removes all dirt 

 and scurf, in addition to furnishing the desired 

 antiseptic action. If pigs are unusually dirty the 

 site of injection should first be cleaned with warm 

 soapsuds. Good technique includes thorough me- 

 chanical cleansing, and nothing else will take its 

 place. 



Dosage of serum. The best rule is to give at 

 least as much serum as the label requires. Serum 

 varies widely in immunizing units per mil, and 

 although the margin^ of safety the increase of 

 the field dose over the laboratory test dose ob- 

 served in individual laboratories is not the same, 

 doses recommended in any particular laboratory 

 are, in a very general way, determined by its indi- 



