SPASM OF DIAPHRAGM 567 



nerve, known as the vagus or pneumogastric. Any irritation of 

 this nerve will produce the irregular spasm-hke contractions of the 

 diaphragm which are known as thumps. In man these same spas- 

 modic jerkings of the diaphragm are known as hiccup. 



Causes. — Thumps was for a long time believed to be due to 

 palpitation of the heart. In fact, there are many men to-day who 

 will call the condition palpitation of the heart. This is a mistake, 

 as can be very easily determined. If the hand is placed over the 

 heart, and the heart-beats counted at the same time that the con- 

 tractions of the diaphragm are noted, it will be seen that there is 

 no relation between the two. 



The direct cause of thumps is any irritation of the nerve which 

 supplies the motive power to the diaphragm. This irritation may 

 be caused in a number of ways. Among the most common causes 

 are diseases of the digestive apparatus. Inflammation of the 

 stomach and bowels are often complicated by the development of 

 thumps. This is a sign of a very severe inflammation, and fre- 

 quently means death for the sick animal. Thumps are especially 

 common in young pigs. Lack of exercise and overloading of the 

 stomach are other very frequent causes of the disease in young pigs. 

 Absorption of chemical poisons, as from the drinking of carbolic 

 acid or bichlorid solution, is a not infrequent cause for thumps. 

 Diseases of the chest and heart or inflammation of the spinal cord 

 may result in thumps. In hog-cholera thumping often develops as 

 a complication late in the course of the disease. 



Symptoms. — The most prominent symptom of thumping is the 

 jerking movement of the body. At each contraction of the dia- 

 phragm there is a bulging out of the flanks and a drawing in of the 

 ribs. Sometimes at each thump there is a peculiar sound made 

 resembUng somewhat the noise produced by hiccup in man. The 

 symptoms are usually worse when the stomach is full. These 

 thumping movements may be forcible enough to sway the body 

 back and forth. In some cases the thumping occurs at the same 

 time as the heart-beat, but in the majority of cases it is irregular 

 in time and bears no relation to the heart-beats. 



Course. — The course of this condition is variable. It may last 

 a few days or for several weeks. In long-drawn-out cases the 

 animal loses flesh and becomes run down and stunted. 



