ABDOMEN, 165 



latter, the stomach, liver, intestines, bladder and other organs. 

 The ribs form the walls of the chest The contents of the 

 belly (consisting mostly of the intestines) are kept in their 

 place chiefly by powerful ligaments, the principal one of 

 which is the abdominal tunic (p. 28), and by muscles. These 

 structures are respectively attached to the margin of the front 

 part of the pelvis, to the rear part of the breast bone, rear- 

 most edge of the ribs, and to the sides of the loin vertebrae, 

 thus bridging over the vacant space. We may, then, fairly 

 assume that the lines of the abdomen should form a con- 

 tinuation of the general contour of the chest. As the 

 straight muscle of the abdomen which covers the lower 

 portion of this cavity, is the chief muscle that bends the 

 back, the horse cannot be thoroughly *'fit'' for work, if this 

 muscle is unduly pressed down by the intestines, and is 

 consequently prevented from contracting to its full extern. 

 This straight muscle and the other muscles of the abdomen 

 aid in the process of breathing, which will be more or less 

 interfered with, if these muscles have to constantly strive 

 against undue pressure from the contents of the cavity they 

 cover. Besides, if the intestinal mass is greater than it 

 ought to be, it will hamper the action of the lungs by forcing 

 the diaphragm too far into the chest ; it will add to the 

 weig^ht to be carried ; and will militate agfainst speed by 

 t Jing to bring the centre of gravity to I. rear 'and by 

 thus mcreasmg the stability of the equilibnum (p. 41). 

 Although the subject of feeding is not within the province of 

 this book, it may not be out of place if I mention that the 

 practice of giving horses large quantities of soft food (boiled 

 turnips, for instance), which they can quickly consume, exerts, 

 among other evils, a very injurious effect on the muscles of 

 the stomach, intestines and abdomen ; for, being deprived of 

 the rest which is necessary to their repair and development, 

 by the continued pressure resulting from the presence of the 

 bulky food, these muscles soon become ill-fitted to perform 

 their work. On the other hand, we should guard against a 

 ''tucked up" condition of belly, which will indicate illness, 



