Anatomical Changes. 299 



found an interior pressure of 1/12 atmosphere. Marek made his experiments by 

 connecting the manometer with the pylorus by means of a rubber tube filled with 

 water and he found that the normal gastric wall of the dead horse required an 

 interior pressure of 10 to 13.5 cm. of mercury before rupture occurred. 



Anatomical Changes. The stomach is dilated to a multiple 

 of its volume; after a cut into the tense gastric wall large 

 amounts of gases escape often in a forcible manner. In rare 

 cases the stomach contains only food-mash and gases; usually 

 there is much fluid mixed with the food-mash. The mucosa 

 shows evidence of an acute catarrh, sometimes also hemorrhages. 

 In rupture of the stomach (ruptura ventriculi) one finds usually 

 gastric contents, more or less mixed with blood, in the anterior 

 portion of the abdominal cavity or between the fold of the omen- 

 tum majus ; the peritoneum shows the signs of an acute inflam- 

 mation. Rupture occurs always in the region of the large curva- 

 ture (in the experiments of the authors, mentioned above, the 

 rupture Avas likewise in the same region) ; the margins of the 

 tear are swollen, ragged, covered with blood coagula, the open- 

 ing is largest in the peritoneal coat, smaller in the retracted 

 muscularis, smallest in the mucosa. Sometimes the peritoneal 

 covering of the stomach alone ruptures, while the two other 

 strata of the wall remain intact. In other cases muscle fibers 

 in the neighborhood of the cardiac end are pushed apart so that 

 the mucosa here rests directly upon the peritoneum._ 



The lungs are in a condition of passive congestion ; some- 

 times there is a tear into the diaphragm with a protrusion of 

 parts of the intestines or liver into the thoracic cavity. 



Symptoms. The symptoms of primary acute dilatation of 

 the stomach usually occur within four, exceptionally only seven 

 hours, after ingestion of feed. The patients draw back from 

 the crib, he back in their halter, and are listless. Very soon the 

 symptoms of colic appear; these are severe and protracted or 

 tliey may be interrupted by short, painless intervals. Some- 

 times such intervals are entirely absent. The animals throw 

 themselves recklessly, roll persistently and often sit down on 

 their haunches in dog-position. However, occasionally the col- 

 icky symptoms are only mild ; they are entirely absent in dila- 

 tation of the stomach due to the ingestion of cold water (Mou- 

 quet). In such cases the authors have, however, always found 

 on post-mortem examination an inflammation of the gastric mu- 

 cosa. The claim of Forssell that violent symptoms of pain are 

 absent in uncomplicated dilatation of the stomach is disproved 

 by general experience. 



The exhaled air frequently has a peculiar sour smell. 

 Belching occurs in the majority of cases, sometimes also gag- 

 ging and vomiting, with the expulsion of a sour-smelling fluid 

 mixed with particles of food from the anterior nares and also 

 sometimes from the mouth. One can also observe undulatory 

 motions towards the head along the jugular groove. Pressure 

 upon the left jugular groove often excites belching. 



