90 THE COMMON COLICS OF THE HORSE 



majority of cases, we have a state of impaction from end 

 to end of the alimentary tube. What, then, will be the 

 cause of the pain now ? It may be, and is partly, due to 

 pressure on, and consequent irritation of, the delicate 

 nerve-endings in the bowels themselves. When, how- 

 ever, we consider that the bowels, already crammed 

 to their full with half-digested matter, are sometimes 

 further distended by the evolution of gases from the 

 accumulated faecal masses, we may confidently assert 

 that we have another and totally different condition of 

 the bowels to reckon with. I am alluding to ' tonic 

 spasm.' When a muscle or its motor nerve receives 

 an abnormal number of vibrations or is overstimulated, 

 instead of contraction being followed by relaxation, 

 permanent contraction or tetanus ensues. The bowels, 

 distended beyond a certain point, are retained in a state 

 of tonic cramp in their ineffectual attempts to deal with 

 the enormous masses they contain. That this is so is 

 fully proved by the entire cessation of peristalsis in many 

 of our cases, as witnessed by ausculation. Call it tonic 

 spasm, atony, paralysis of the bowel, or what we will, it 

 still remains that we have a torpid and stationary condi- 

 tion of the bowels to treat. It is this state of tonic 

 spasm of the whole of the intestinal tract that has, 

 in my opinion, been so generally overlooked in the 

 treatment of veterinary obstructive colic. 



3. What is the actual condition we are called upon to 

 treat ? The favourite, but evasive, reply of the practi- 

 tioner of veterinary medicine to that question is, ' Remove 

 the cause, and the effects or actual condition will cease,' 

 and, accordingly, in every case he gives a dose of physic. 

 That physic is invariably aloes. I maintain, however, 

 that, before we proceed in an attempt to empty the 

 bowels by such a mechanical method as the adminis- 



