IMPACTION Of ThU rumen. 177 



deep palpation it is even possible to detect marked resistance and a 

 certain characteristic firmness resulting from accumulation of food. The 

 percussion sounds over this region are dull, and pressure causes pain, as 

 though the rumen and peritoneum were inflamed. When the open hand 

 is laid flat on the rumen and thrust downwards, no peristaltic move- 

 ment can be discovered. Finally, on auscultation the normal sounds, 

 including crepitation, fermentation, and rolling sounds are all absent. 



There are no well-marked general symptoms. Respiration and 

 circulation are hardly accelerated, nor is the artery particularly tense. 



Course and Termination. The course of the disease varies, and the 

 condition may be divided into two forms, acute and chronic. The first 

 develops in a single day, and may cause death by the same mechanism 

 as acute tympanites — i.e., asphyxia or carbonic acid poisoning; the 

 other continues for five, ten, or even twenty or thirty days, according to 

 the promptitude with which treatment is undertaken. 



In protracted cases, however, the indigestion itself ceases to be as im- 

 portant as the complications. Sometimes spontaneous recovery occurs, 

 the food passing away towards the intestine, or even being vomited, 

 though the latter conclusion is rare. Eecovery may also follow from 

 treatment. If the disease is neglected it may become complicated with 

 gastro-enteritis. 



The diagnosis is not very difficult. Indigestion resulting from im- 

 paction is distinguished from acute tympanites by its less rapid course 

 and by the less marked distension of the rumen (in this case due to solid 

 food), and from acute gastro-enteritis by the varying degree of fever 

 which accompanies the latter condition. 



Prognosis. The prognosis is always grave, even in cases of acute 

 indigestion resulting from eating green food. 



In this case gaseous indigestion occurs as a complication, and neces- 

 sitates immediate intervention. The other forms may rapidly yield to 

 proper treatment, or, in spite of every care, may give rise to prolonged 

 complications. 



Lesions. On post-mortem examination of animals which have died 

 of complicated forms of the disease, we find certain lesions peculiar to 

 gaseous indigestion associated with impaction of the rumen. 



If death has followed the consumption of root pulps, we see signs of 

 poisoning. As a consequence of prolonged stagnation of food in the 

 rumen, there follows an exaggerated organic fermentation, whose pro- 

 ducts are absorbed through the stomach or intestine and pass into the 

 circulation. 



These various fermentations, which may be of the lactic, butyric, 

 and even putrid order, produce changes in the mucous membrane of the 

 rumen ; wide tracts of the epithelium may be shed, exposing the corium, 

 D.c. N 



