380 KENNEL DISEASES. 
CHAPTER II. 
DIPHTHERIA. 
DiPHTHERIA is an acute infectious disease, caused by a specific micro- 
organism or germ, and characterized by the formation of a false-membrane, 
which usually appears on the lining of the nose, throat or passage to the lungs 
or bronchial tubes, also occasionally upon wounded surfaces. The develop- 
ment of this membrane is accompanied by congestion and swelling of the 
underlying and adjacent tissues, and more or less fever, prostration, and other 
disturbances of the general system. 
While the real exciting cause is doubtless the diphtheria bacillus or pto- 
maines produced by it, there are doubtless other influences intimately con- 
cerned in the causation, and which create what is termed susceptibility to 
the disease. But of these practically nothing is as yet known. It has been 
the general impression that it was much more liable to occur among the badly 
nourished and those exposed to faulty drainage and emanations from filth. 
But it is exceedingly doubtful if such conditions have any considerable in- 
fluence upon it. It appears, however, reasonable to assume that the dogs too 
closely confined to kennels, even if the sanitary condition of the same be good, 
and not allowed sufficient exercise in fresh air and sunshine, are the easiest 
victims of the malady. Deprived of these the general health is more or less 
impaired; even slight exposure in bad weather may excite an irritation or low 
form of inflammation in the nasal passages and throat, and the lining mem- 
brane of these parts is then in a condition most favorable for the lodgment and 
propagation of the diphtheria germ. In other words, the soil is then right for 
the seed. And in truth there is every reason for the belief that a healthy 
mucous membrane is eminently capable of successfully resisting this malig- 
nant germ. 
The false membrane first appears as thin white patches, but later, especially 
in very severe cases, it thickens and has a dirty grayish or yellowish tinge. 
The constitutional affection is a blood-poisoning, which occurs through 
absorption of the poison at the points at which the disease first fixes itself. 
While dogs but rarely fall victims to diphtheria, the fact has been proved 
that they and various other domestic quadrupeds are not exempt from it. 
Moreover, it would seem that between this disease in such animals and human 
diphtheria there is a close resemblance. Indeed, a case of contagion between 
a calf and man has been observed; while by the means of inoculation — the 
