DIGESTIBILITY OF SOME ANIMAL FATS. 
9 
Flurin 1 was interested in determining the relative digestibility of 
butter and beef tallow, which he regarded as typical animal fats. 
The average coefficients of digestibility were found to be 95.9 per 
cent and 92.8 per cent, respectively. 
Levites 2 studied the relative digestibility of beef fat, lard, and but- 
ter, and found that butter and beef fat were both 96 per cent digested. 
Grindley et al., 2 in experiments to determine the thoroughness of 
digestion of various meats, found that the average digestibility of 
fat present in a shoulder of beef rich in fat was 97.3 per cent, but 
this coefficient may not be applicable to kidney fat. In an attempt 
to compare the digestibility of edible fats, using guinea pigs as sub- 
jects, Moore 2 found that the fat of raw beef suet was 73.7 per cent 
utilized. 
In the work here reported the fat was incorporated in a blanc 
mange in the manner previously described. During the first three 
experiments the subjects ate large amounts, approximately 140 
grams per day, but they reported a laxative effect from eating this 
quantity of fat. As this seemed to indicate that the limit of toler- 
ance was being approached, smaller quantities of fat were eaten in 
the succeeding periods. 
The results of the digestion experiments with beef fat contained in 
a simple mixed diet follow : 
Data of digestion experiments with beef fat in a simple mixed diet. 
Weight. 
Water. 
Protein. 
Fat. 
Carbo- 
hydrates. 
Ash. 
Experiment No. 61, subject W. D.: 
Blanc mange containing beef fat 
Wheat biscuit 
Grams. 
2,255.5 
544.9 
1,354.0 
Grams. 
1,134.5 
46.3 
1,176.6 
Grams. 
45.1 
73.0 
10.8 
Grams. 
412.8 
6.0 
2.7 
Grams 
649.6 
410.9 
157.1 
Grams. 
13.5 
8.7 
Fruit 
6.8 
Total food consumed 
4,154.4 
80.5 
2,357.4 
128.9 
17.5 
111.4 
421.5 
23.8 
397.7 
1,217.6 
31.2 
1,186.4 
29.0 
Feces 
8.0 
21.0 
Per cent utilized 
86.4 
94.4 
97.4 
72.4 
Experiment No. 62, subject E. M.: 
Blanc mange containing beef fat 
Wheat biscuit 
2,486.0 
499.8 
1,220.3 
110.2 
1,250.5 
42.5 
1,060.4 
49.7 
67.0 
9.8 
454.9 
5.5 
2.4 
716.0 
376.8 
141.6 
110.2 
14.9 
8.0 
Fruit 
6.1 
Total food consumed 
4,316.3 
102.9 
2,353.4 
126.5 
26.9 
99.6 
462.8 
28.8 
434.0 
1,344.6 
36.8 
1,307.8 
29.0 
Feces 
10.4 
Amount utilized 
18.6 
Per cent utilized 
78.7 
93.8 
97.3 
64.1 
Experiment No. 63, subject R. L. S.: 
Blanc mange containing beef fat 
Wheat biscuit 
2,141.4 
533.7 
1,250.2 
69.0 
1,077.1 
45.4 
1,086.4 
42.8 
71.5 
10.0 
391.9 
5.9 
2.5 
616.7 
402.4 
145.0 
69.0 
12.9 
8.6 
Fruit 
6.3 
Sugar 
Total food consumed 
3,994.3 
116.1 
2,208.9 
124.3 
28.7 
95.6 
400.3 
44.2 
356.1 
1,233.1 
32.4 
1.200.7 
27.8 
Feces 
10.9 
Amount utilized 
16.9 
Per cent utilized 
76.9 
89.0 
97.4 
60.8 
i Diss., Army Med. Acad. St. Petersburg, 1890, p. 52. 
6829°— Bull. 310—15 2 
2 Loc. cit. 
