224 DICTIONARY OF THE VETERINARY ART. 



Dropsy. This disease consists in a collection of serous or 

 watery fluid, either in cavities, as the chest, belly, or ventri- 

 cles of the brain, or in the cellular membrane under the skin. 

 Dropsy is more a symptom of disease than a disease itself; 

 but sometimes, on account of the violence and danger of the 

 symptom, it is often treated as a disease. The proximate 

 cause is a check to perspiration j the remote cause is bleeding, 

 or any thing that can debilitate the general system. 



Dropsy of the Chest. This is sometimes a consequence 

 of disease of the lungs ; and when it happens, those important 

 organs generally are so far disorganized, or injured, that 

 there is very little chance of the animal's recovery. 



Dropsy of the Belly, or Ascites. The causes are the 

 same as above ; the only difference is, that, from circumstan- 

 ces predisposing the fluid is determined on the peritoneum, 

 (see Peritoneusi,) instead of the pleura. 



Duct. A membranous tube, or canal, through which cer- 

 tain fluids are conveyed. Thus the lachrymal duct conveys 

 tears from the eyes to the nose. 



Dung. By examining a horse's dung, we are enabled to 

 judge of the state of his health. When the dung is hard, 

 and in small knobs, and covered with slime, laxative medi- 

 cines are beneficial ; and when it is passed in too great 

 quantities, it commonly arises from too liberal allowance of 

 food. If oats are voided whole, it will generally be found 

 to be caused either by a defect of the teeth, or by a too vora- 

 cious appetite, occasioning the food to be swallowed without 

 mastication ; in which case the animal should be fed on 

 shorts, or scalded food. 



Duodenum. The first intestine that comes from the stom- 

 ach. (See Intestines.) 



Dura Mater. A strong membrane that invests the brain 

 and divides it into two lobes. It likewise separates the large 

 brain (cerebrum) from the small, or cerebellum. 



