112 DISEASES OF THE DIGESTIVE APPARATUS. 



Digital examination or palpation may be practised over the entire 

 region of the flank. It shows whether the rumen is full or empty, 

 reveals the consistence of the contained food in cases of chronic indiges- 

 tion, the sensibility of the walls, and the rate and order of the muscular 

 contractions. Direct or indirect percussion maybe carried out on a hori- 

 zontal line from the twelfth rib as far back as the flank, and vertically 

 from the lumbar vertebrae to the white line. In health one discovers in 

 young animals an u^^per zone of normal resonance due to gas, a zone of 

 semi-dulness and an inferior zone of absolute dulness, due to the liquids 

 in the rumen. The spleen, which is attached to the supero -anterior sur- 

 face of the left side oJ the rumen, does not seriously restrict the area 

 open to percussion. 



In pathological conditions percussion from above downwards may pro- 

 duce a tympanitic sound, due to gaseous indigestion or a clear sound 

 throughout the greater portion of the vertical diameter suggestive of 

 acute gastro-enteritis with the formation of gas in the rumen, or of 

 adhesive peritonitis preventing the rumen from collapsing. Indigestion 

 due to excess of solid food, on the contrary, is characterised by a dull 

 sound throughout the entire region from above downwards. Percussion 

 along a horizontal line permits of the delimitation of certain zones which 

 vary a great deal in area, according to the case. 



Auscultation is more instructive than percussion. Like percussion, it 

 may be practised throughout the entire depth of the abdomen, from the 

 transverse processes of the lumbar vertebrae as far as the white line, and 

 in a horizontal direction from the eleventh rib to the region of the flank. 



Auscultation of the upper zone enables one to detect sounds of 

 deglutition, gurgling sounds (glou-glou), and a sound resembling falling 

 water, due to the movement of solids or liquids in the rumen and 

 reticulum. The sounds heard vary in difterent cases, and depend on 

 the state of repletion or of emptiness of the rumen. 



Auscultation of the middle zone reveals : 



Firstly, a very special crepitation sound, which may be compared to 

 the deflagration of a handful of salt thrown on burning coal. It is 

 believed to result from the bursting of bubbles in the contents of the 

 rumen under the action of normal digestion. 



Secondly, a churning sound produced by the rhythmic peristaltic 

 contractions of the rumen, by which the substances ingested are very 

 intimately mixed. By applying the ear over the flank region or by 

 palpation the rhythmic contractions of the rumen, two per minute in 

 most cases, can readily be perceived. 



In practice examination of the rumen is confined to these four methods. 



Puncture. From an exclusively scientific point of view, exploration of 

 the rumen also comprises analysis of the gas collected through puncture 



