674 



EXPERIMENT STATION RECORD. 



number of the experiments were made with dogs; in others the authors themselves 

 were the subjects. In the latter experiment, the butter or butter substitute was con- 

 sumed as part of a simple mixed diet for periods of 3 days each. The coefficients 

 of digestibility found in the experiments with men follow: 



Coefficients of digestibiUly of rations containing butter and butter substitutes. 



Subject H: 



Diet containing sana 



Diet containing butter — 

 Diet containing margarine 



Subject W: 



Diet containing sana 



Diet containing butter 



Diet containing margarine 



Dry 

 matter. 



Per cent. 

 92.80 

 94.31 

 94.22 



93.08 

 96.17 

 94.94 



Protein. 



Per cent. 

 80.93 

 84.09 

 85.12 



82.24 

 89.71 

 88.65 



Fat. 



Per cent. 

 93.79 

 96.05 

 96.08 



95.30 

 97.33 

 95.98 



The authors point out that there was practically no difference in the digestibility of 

 the rations containing the different sorts of fat. Similar results were obtained in the 

 experiments with dogs. 



The comparative digestibility of raw, pasteurized, and cooked milk, C. F. 

 DoANE and T. M. Price {Maryland Sta. Bid. 77, pp. 38, figs. 3). — The digestibility of 

 milk treated in different ways is discussed in the light of an extended review of the 

 literature of the subject and of opinions which were gathered by interviews and cor- 

 respondence with physicians in charge of children's hospitals. Digestion experiments 

 with calves are reported on the comparative value of whole milk (raw and pasteur- 

 ized at different degrees) and skim milk. Special crates were devised to accommo- 

 date the calves during the experiments, as well as bags for collecting the feces. The 

 average results follow: 



Digestibility of rate, 2Msteurized, and cooked milk by calves. 



Protein. 



Fat. 



Whole milk, raw 



Whole milk, pasteurized atJ67° for 10 minutes 



Whole milk, cooked 



Skim milk 



Whole milk, raw 



Whole milk, pasteurized at 140° for 30 minutes 



"It is almost always stated by authorities on such subjects that milk is entirely 

 digestible. Theoretically, perhaps, it is, as it contains none of the material which 

 is recognized as the indigestible part of grains and fodders. In practical work, how- 

 ever, there is found to be a relatively large porti(jn indigestible. In the work recorded 

 in this bulletin the digestibility of the milk fed would average about 93 per cent with 

 the protein and a little higher with the fat, some of the percentages being much 

 lower than this in individual cases. It is likely that had a smaller portion of milk 

 been fed a larger percentage would have been digested, and by reducing the amount 

 to the muiimum required to sustain life it is possible that practically all fed would 

 have been utilized in the system. But where sufficient milk is fed to insure substan- 

 tial growth, nearly one-tenth of the dry substance is undigested." 



The following general conclusions were drawn from the tests as a whole: 



" Eaw milk is more easily digested when fed to calves than either pasteurized or 

 cooked milk. Contrary to theory, cooked milk when fed to the calves used in these 

 experiments caused violent scouring in the majority of trials. 



"A majority of physicians in charge of children's hospitals corresponded with 

 favored the use of raw milk f(jr infants when the milk is known to be in perfect con- 



