Increasing Quantities of Fat in Diet on Metabolism in Dogs. 289 



On this point, in normal dog No. 2, the analysis was carried out during 

 two periods, as shown in Table XV. In the first period the dog re- 

 ceived 15*20 grams of fat daily, and four days were separately 

 analysed; while during the second period the dog received 65*19 

 grams of fat, and three days were separately analysed. 



We see that the quantity of free fatty acids, as compared to neutral 

 fat, is somewhat greater on the diet poor in fat, while on the diet rich 

 in fat it is very markedly so, being no less than 0*314 gram of neutral 

 fat and 1*359 grams of free fatty acids. The soap is also very 

 markedly increased, namely, from 0*043 to 0*591 gram by increasing 

 the quantity in the fat diet ; the cholesterin, however, remains the 

 same, being 0*066 and 0*061 gram. The percentage, taking the total 

 ether extract as 100, on the diet poor in fat, is 40*13 per cent, of fat as 

 neutral fat, 44*89 per cent, as free fat acids, and 4*60 per cent, as fat 

 acids in form of soaps ; while, when the diet is rich in fat, and the 

 faeces, in spite of the increased absorption, contained more than double 

 the quantity of ether extract, these contained only 13*63 per cent, as 

 neutral fat, 59*45 per cent, as free fat acids, and 24*12 per cent, as 

 soaps. The percentage of cholesterin naturally differs owing to the 

 increased quantity of total ether extract. 



Table XVI. In dog 1, on a diet rich in fat, containing no less than 

 62 grams of fat, the total result is very much the same as that obtained 

 in the previous table, the percentage of fat acids being in excess of 

 neutral fat ; the cholesterin, however, in this case, was somewhat 

 higher than in the former dog. 



Table XVII. When the partial removal of the large intestine was 

 carried out during three days' analysis on a diet containing 51*73 

 grams of fat daily, the same holds good, the quantity of cholesterin, 

 however, corresponding with Table XVI being no less than 0*145 gram. 



Table XVIII. In the case of dog 4, in which the large intestine has 

 been entirely removed, on a diet comparatively poor in fat 29*7 grams 

 the quantity of free fatty acids is very much in excess of the 

 neutral fat, the soaps being also slightly in excess of the fat acids ; 

 the cholesterin, on the other hand, is very markedly decreased, the 

 average being only 0*025 gram per diem. 



Table XIX. Again, in dog 5, on a diet containing 41*6 grams of fat, 

 the animal had slight diarrhrea; throughout the three days experi- 

 mented on the quantity of fat acids was again in excess of the neutral 

 fats, and the fat acids as soaps were not increased. The cholesterin, as 

 in the former dog, was on the whole diminished, being only 0*069 gram. 



In Table XX the average results of the two normal dogs are compared 

 with that of partial and complete removal of the large intestine, and it is 

 seen that as far as the fat is concerned the composition of the ether 

 extract in the faeces remains practically the same, whether the large in- 

 testine is present or absent, the fat acids being in both greatly in excess 



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