APPENDIX II 
DISINFECTION 
A disinfectant is an agent which destroys pathogenic 
germs, or renders ferments inactive; it is distinguished 
from antiseptics in that the latter do not necessarily 
destroy but inhibit the growth and multiplication of 
putrefactive organisms, and from deodorants by the fact . 
that these remove undesirable or offensive odours, without 
the surety of killing the microbes, or hindering their 
growth. Deodorising is not accomplished by merely 
substituting one smell for another in a room where 
putrefactive processes are generating a totally different 
odour. True deodorants attack the cause of the evil smell, 
although they themselves may be odourless; examples 
are charcoal, Condy’s fluid, hydrochloric or nitric acids, 
chlorine, etc. Many disinfectants are also deodorants, 
though few deodorants could be termed disinfectants. 
Disinfectants exert their bactericidal effects in various 
ways, viz.: By oxidation, e.g. potassium permanganate, 
ozone, chlorinated lime, hydrogen peroxide; by coagula- 
tion and desiccation, e.g. metallic salts such as silver 
nitrate, corrosive sublimate, etc.; by protoplasmic poison- 
ing, ¢.g. carbolic acid and its various derivatives. 
Many disinfecting agents are very toxic, and dogs are 
peculiarly susceptible to poisoning from certain varieties 
by absorption through a wound or the skin ; hence careful 
choice must be made according to whether the disin- 
fectant is to be used for cleansing walls, floors, benches, 
and other objects, or will be employed in the dog’s bath 
water, or to sterilise wounds, etc. Carbolic acid, some 
tar preparations, and the various mercuric germicides, are - 
all dangerous to the dog, and should be used with great 
caution. Disinfection may be carried out by a variety of 
means, such as fumigating, spraying, baking, boiling, . 
chemical solutions, sunlight. 
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