iv DIGESTION IN THE INTESTINE 229 



of the small intestine, and particularly to determine the limits of 

 its adaptability, it is useful (as in the preceding chapter, in re 

 gastric digestion) to consider the effects of more or less extensive 

 resection of the several parts of the gut. Many of these operations 

 were initiated by surgeons, either on dogs with the simple object 

 of exploring in order to make clinical application of the results, 

 or on man with the therapeutic object of relieving cancer and 

 intestinal strictures consequent on strangulated hernia, cicatrised 

 constriction of the bowel, volvulus, traumatic rupture of the 

 small intestine, tumours of different sorts developed in the walls 

 of the intestine, and so on. 



Senn was the first who undertook a series of experiments of 

 this kind on animals, and he came to the conclusion that the 

 resection of a third of the small intestine is a hazardous operation, 

 which results sooner or later in the death of the animal from 

 marasmus. Trzebicky (1894) continued the experiments, removing 

 first the upper portion of the jejunum, next the middle part of 

 the small intestine, then the extreme end of the ileum. In all 

 the dogs thus operated on, he found a diminution in the total 

 weight of the animal, proportional to the absolute or relative 

 length of intestine resected. When the excised loop does not 

 exceed certain limits, the loss of weight is arrested after a time, 

 and is succeeded by an increase which sometimes surpasses the 

 initial weight of the animal. 



Unlike Senn, he found that dogs were well able to bear the 

 loss of half the small .intestine, the duodenum of course being 

 excluded. Even when these limits w'ere slightly exceeded the 

 animal could survive with a properly selected diet. Removal of 

 two-thirds of the gut, on the contrary, inevitably caused the death 

 of the animal, owing to insufficiency and disturbance of the 

 digestive function and absorption, as shown in obstinate diarrhoea, 

 followed by vomiting. The animal has a furious appetite, and 

 eats enormously, but still grows thinner from day to day, and 

 perishes of inanition. The autopsy shows typical death from 

 starvation, characterised especially by the almost total dis- 

 appearance of adipose tissue. In the intestine there is, moreover, 

 a conspicuous dilatation of the part lying above and below the 

 suture, but without compensatory hypertrophy of the intestinal 

 walls, as supposed by Senn. Trzebicky was eventually convinced 

 by his experiments that resection of the higher part of the small 

 intestine (jejunum) is more serious than that of the lower part 

 (ileum). Owing to its great physiological importance, this 

 conclusion deserves to be confirmed by further experiments under 

 conditions as far as possible identical and comparable. If 

 established, it would show that the functional value of the small 

 intestine for digestion decreases from above downwards, i.e. is 

 greatest in the duodenum, moderate in the jejunum, least in the 



