16 



ANIMAL MANAGEMENT. 



prominent, standing out like veins on the skin, while pain and swelling 

 of the limbs and nearest glands is frequently observed. The glands 

 under the jaw, beneath the arm, and inside the thigh, are those most 

 frequently observed to be so affected. 



The body, excluding the limbs, is divided into two great cavities — the 

 chest, and the belly. 



The Chest contains the heart, the great blood-vessels and the lungs ; 

 while a portion of the gullet passes through it en route to the stomach. 

 Its length extends from the point of the breast-bone to the midriff 

 (diaphragm), while on each side the ribs form a strong, sufficiently 

 elastic cage to protect the organs it contains, and permit their free 

 movements during respiration. 



The first eight ribs are firmly jointed to the breast-bone, and this 

 makes a rigid protection for the heart, which is situated between them ; 

 while the remainder are attached less firmly to each other, and allow 

 greater freedom of movement. The space between the first ribs may be 

 termed the entrance to the chest, and through this the windpipe 

 (trachea), and gullet (oesophagus) make their entry. 



Respiration i^Breathijig). — Air is drawn through the nostrils or 

 mouth (in the horse through the nostrils only), passes through the 

 larynx (organ or voice), down the wind-pipe, and enters the 

 lungs. In the lungs the air and blood mix, and exchange the elements 

 they require ; the used, polluted air is then expelled, a slight pause 

 ensues, and the process repeats itself. 



The Nostrils differ in shape according to the animal's requirements, 

 those of the galloping horse being thin, widely open, and capable of 

 still wider distension, if necessary, to increase the air supply, while oxen 

 and camels not being required to go such a pace, are provided 

 respectively with a rigid, thick-edged opening, and a pendulous slit. 



The Larynx^ the organ which produces the voice, is situated in the 

 throat between the branches of the lower jaw, where it may be readily 

 felt. Its body is made of cartilages, which are jointed together so that 

 the surrounding muscles can narrow or widen its calibre. Food and 

 water pass over its opening on their way down the gullet, and in order to 

 prevent their entrance a lid is provided which closes automatically, and 

 with water-tight accuracy, whenever the animal swallows. Coughing and 

 difficulty in swallowing are immediately experienced if there is anything 

 the matter with the opening (the glottis), or the lid (the epiglottis), e.g.^ 

 during a sore throat. Inside are two thick elastic cords, so placed as to 

 form a triangular opening with the floor of the organ ; when the calibre is 

 varied by the action of the muscles, the edges of the cords are rendered 



