Increasing Quantities of Fat in Diet on Metabolism in Dogs. 297 



The decrease in the alkaline sulphates and no alteration in the 

 quantity of aromatic sulphates during the second period causes the 

 ratio A to B to fall from 9:1 to 8:1, that is to say, by discussing 

 only these ratios, one would consider that the intestinal putrefaction 

 had really been increased instead of decreased. However, on increasing 

 the fat in period 3, the decrease in the aromatic sulphates was suffi- 

 cient to counteract the decrease in total sulphates, so that the ratio was 

 8-5 : 1. 



On turning to Table XXII, normal dog 2, we see the increase of fat 

 in the food causes, as in the preceding dog, a decrease in the quantity 

 of urine, and at the same time a decrease in the quantity of nitrogen 

 excreted; there is also in this case a more marked decrease in the 

 quantity of alkaline sulphates, but this is due to the greater decrease 

 in the quantity, of nitrogen. The aromatic sulphates, however, are 

 slightly decreased, the normal ratios being 7:1, while the ratio on the 

 increased fat diet is 6'6 : 1. We here have also, even in spite of a 

 decrease of aromatic sulphates produced by increasing the fat in the 

 diet (since the alkaline sulphates are more markedly decreased), a 

 smaller ratio, which would lead us to believe that intestinal putrefac- 

 tion is increased. 



From these two dogs we see that the old idea that the ratio 8 or 

 10 : 1 should be considered as the normal ratio indicating intestinal 

 putrefaction must be corrected, and that in future it is not sufficient to 

 make out the ratio of the total day's urine, but it is essential to com- 

 pare the quantities in a given space of time, for on a diet rich in fat 

 the ratio may be very much diminished, say to 6 : 1, in spite of the 

 aromatic sulphates being also diminished. 



It would further appear that in a normal dog fat added to the diet, 

 if anything, tends to decrease the amount of aromatic sulphates, so 

 that the increase of fat does hot cause an increase of intestinal putre- 

 faction. 



Table XXIII. We now come to discuss the dog in which the large 

 intestine was in part previously removed. In this case we have the 

 same decrease in water and nitrogen in the urine by an increase in the 

 fat as in normal dogs, and also a decrease in the alkaline sulphates and 

 aromatic sulphates. In fact, the results, as far as the sulphates are 

 concerned, obtained in this dog, correspond exactly with those found in 

 the two normal dogs, so that we can conclude the partial removal of 

 the large intestine has no effect on the sulphates. 



Table XXIV. In dog 4 the effect of the total removal of the large 

 intestine was investigated twice on two diets. In the first the diet 

 contained 9*71 grams of fat, and in the second 2 9 '71 grams. 



We see in this dog that increasing the fat causes, as in the normal 

 dog, a decrease in water and nitrogen in the urine, and this is also 

 accompanied by a decrease in the alkaline sulphates, but no alteration 



