ig6 A MANUAL OF VETERINARY PHYSIOLOGY 



of cellulose is the production of a considerable quantity of gas. 

 Ellenberger is of opinion that, in addition to the functions named, 

 other digestive changes occur ; he says that carbohydrates are 

 digested by means of enzymes contained in the food, and in this 

 way starch and cane sugar are converted into maltose. Proteins 

 are also slowly converted into peptones, not through any true 

 peptic ferment, but by some enzyme provided by the food. The 

 rumen never empties itself ; even after prolonged starvation it 

 contains food. In young ruminants digestion occurs principally 

 in the fourth stomach, the other compartments being rudimen- 

 tary ; when the young animal is placed on solid food, it is remark- 



Fig. 70.— The Gastric Compartments and True Stomach of Ruminants 



(Colin). 



C, The oesophagus ; A, A, left hemisphere, B, B, right hemisphere of the rumen ; 

 D, the reticulum ; E, the omasum ; F, the abomasum. 



able how soon these compartments develop, and the process of 

 remastication established. 



The Reticulum, or second gastric reservoir, is a small one 

 placed anteriorly and inferiorly, resting, in fact, on the sternum 

 (see Fig. 72). Its capacity in the ox is 2 litres (3 J pints), and in 

 the sheep 0*2 litre (0-35 pint). Anteriorly it communicates with 

 the rumen by a large opening formed by a constriction of its walls ; 

 the bulk of the organ lies below this opening. Over the lip which 

 separates the two chambers, fluids and solids may pass in either 

 direction. The reticulum communicates with the cesophagus, 

 under the opening of which it is placed like a sac, while on its 

 inner wall is the oesophageal groove, by which it communicates 

 with the omasum. The muscular coat of the reticulum is largely 

 striated, being a continuation of the cesophagus, and, in conse- 



