A better comprehension of these diseased conditions will make for a saner analysis of the great mass of experimental data relating to the various types of bile fistula. Too frequently in the literature the bile fistula material is used to debate a physiological state whereas in reality the animal is in a pathological condition.

It is possible but not easy to keep a bile fistula dog in a normal state for months or years if proper attention is given to the diet and physical state.

The most significant abnormalities are—intestinal disturbances, spontaneous bleeding, osteoporosis, cholelithiasis and duodenal ulcer.

Three types of bile fistula were used in our experiments and each one has its advantages and disadvantages.

Intestinal intoxication is best controlled by diet, by whole bile or bile salts or combinations of dog and ox bile.

Spontaneous bleeding seems to be due to the loss of something by way of the bile and this can be prevented by bile feeding. The blood deficiency appears to be a lack of prothrombin.

Osteoporosis appears inevitably after many months if bile is excluded from the intestine. This state is related to the lack of absorption of vitamin D. It is of some interest that liver feeding will prevent it.

Duodenal ulcers and cholelithiasis are common in bile fistula dogs and absolute control or prevention is not easy.

It may be restated that bile secretion into the intestine is necessary for normal health and even for actual continuation of life beyond a few months' period. Some of these experimental data should be of value to physicians and surgeons in the care and study of human fistula cases and should emphasize the necessity of prompt dietary control.