General Diseases, 327 



DROPSY. 



Dogs, especially old ones, frequently, and from constitu- 

 tional disease, become what is termed "dropsical" i.e., 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 ; hydrops-pericardium, when within the 

 pericardial sac or membrane covering the heart ; hydro- 

 metra, when within the uterus ; hydrocephalus, when 

 within the head ; ascites, when within the peritonea,l sac or 

 abdomen ; anasarca, when within the areolar tissue of the 

 body generally. 



I shall here commence with the form known as ascites, 

 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 active 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 irom 

 the inner faces of the shut serous cavities, a large amount 

 of watery fluid is continually thrown out of the system by 

 ail those services that communicate with the air by the 

 skin, the lungs, the bowels, the kidneys. 



