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A MANUAL OF VETERINARY PHYSIOLOGY 



merit, a horse can only kick outwards with difficulty. It is 

 known as ' cow-kicking,' but this term may also be applied to 

 the forward kick. Striking with the fore-feet and cow-kicking 

 are not common among nor characteristic of British horses ; 

 they are methods of attack particularly employed against man. 

 It is rather remarkable, however, that our horses should be 

 so much more given to kicking among themselves than those of 

 Continental nations. 



In Rearing (Fig. 215), the fore-hand is raised by the centre 

 of gravity being thrown back, the body pushed upwards by the 

 fore-limbs, and at the same time raised by a contraction of the 

 long muscles of the back (A B) which run from croup to neck, 

 attached throughout their whole length to the vertebrae 



(Fig. 216). The muscles 

 of the hind-limbs keep 

 the stifle-joint closed, 

 and the hock-joint open, 

 without which the extra 

 weight would cause the 

 animal to sit down. The 

 position in Fig. 215 is 

 one of perfect stability. 

 More powerful contrac- 

 tions of the muscles in- 

 serted into the cervical 

 vertebrae will pull the 

 body farther back, and 

 if it passes outside the 

 base formed by the hind- 

 feet, the animal comes 

 completely over, either 

 on to its side, or frequently on to the occiput when rearing 

 through temper. 



In Buck-jumping (Fig. 217) the animal springs bodily and 

 suddenly off the ground, the head being depressed between 

 the fore-legs and the back violently arched. In this action the 

 psoas muscles play an important part by bending the hind- 

 quarters inwards, but they cannot by themselves produce the 

 arched condition of spine, which largely depends, apart from 

 the upward spring, upon the ability to get the head down, the 

 neck bent, and the abdominal muscles firmly contracted. Much 

 the same configuration of spine occurs when horses are cast for 

 operation, and in practice this is controlled by keeping the head 

 and neck straight, and the tail from being forcibly drawn in. 

 In buck- jumping it is the spring which displaces the rider. 



Fig. 217. — Buck-Jumping (after Peyremol). 



