General Diseases. 327 
DROPSY. 
Dogs, especially old ones, frequently, and from constitu- 
tional disease, become what is termed “dropsical,” ie, a 
serous exudation takes place in some portion of the 
organism. The usual forms met with in canine practice ~ 
are, hydrothorax, viz., when the exudation is within the 
cavity of the chest; ydrops-pericardium, when within the 
pericardial sac or membrane covering the heart ; Aydvo- 
metra, when within the uterus; hydrocephalus, when 
within the head; ascztes, when within the peritoneal sac or 
abdomen ; axzasarca, when within the areolar tissue of the 
body generally. 
I shall here commence with the form known as ascztées, 
placing the others in their respective classes. 
Ascites, or abdominal dropsy, may be the result of inflam- 
matory action or of chronic disease of the circulating 
system, hence it is either aetzve or passive. 
The active form is usually met with in young dogs, and 
is caused by exposure to damp and cold, especially after 
being heated. The natural exhalation from the skin being 
suddenly checked, the water is retained in the blood 
vessels, and seeks an outpour elsewhere ; and this either 
takes place in the areolar tissue—producing anasarca—or 
in some of the serous cavities of the body, frequently the 
peritoneal, and giving rise to ascites. 
The analogy with human dropsy being very close, a brief 
extract from Sir Thos. Watson’s instructive lecture on this 
subject will not be out of place:—“To comprehend this 
rapid change from a state of health to a state of dangerous 
disease, we must again have recourse to the findings of 
physiology. 
“ Besides the constant exhalation which takes place 1rom 
the inner faces of the shut serous cavities, a large amount 
of watery fluid is continually thrown out of the system by 
all those services that communicate with the air by the 
skin, the lungs, the bowels, the kidneys. 
