ANIMAL PRODUCTION. 799 



varying in degree in the different materials and being markedly increasiMl hy the 

 addition of pancreas tissue, 1>ut not l)y the other eond)inatioiis tested. 



Contribution to the subject of the excretion of g-astric juice by man, A. F. 

 IIoKNHoiui {S/.diid. Avrli. J'hjislol., L'> [1904), A'o. ;>-./, /<y>. JO!i-.'r>S, dr/iiix. 6'). — A !)oy 

 who had had gastrotomy performed because of an injury and was fed almost entirely 

 through a fistula, furnished an opportunity for the study of the iniiuenceof various 

 fact(«rs on the secretion of gastric juice. It was found that the sight of food ditl not 

 cause its excretion. Generally speaking, chewing foods of good flavor cause(i a more 

 or or less active secretion, and chewing foods of unpleasant flavor ai/jjarently 

 influenced the secretion very little, while chewing foods of indifferent flavor was 

 Avithout influence. When substiinces having a sharp or biting taste were chewed, 

 ai)parentlv the secreting glands of the stomach were not stimulated. 



In his experiments the author studieil the acidity and activity of the gastric juice. 

 The investigations are discussed in relation to Pawlow's theories, and the rejiort con- 

 tains a l)ibliography. 



The infl.uence of the diet upon the excretion of uric acid, 1'. Pfeii. [Ztxclir. 

 I'}ii/slol. C'lii'in., //O [190S), No. 1-2, pp. 1-24, 1^1^- 7). — ^\'ith healthy men as subjects 

 the effect of (different foods and combinations of food on the excretion of uric acid 

 was studied. When no meat was eaten the excretion of uric acid was diminished 

 to a small amount. When meat was eaten it was markedly increased. When a 

 diet containing no jn-otein was consumed the uric acid was still excreted and in 

 about the same way as when no meat was eaten. The author studied the time rela- 

 tions of the excretion of uric acid and relatetl topics. 



ANIMAL PRODUCTION. 



The available energ-y of timothy hay, II. 1*. Aioisbv and .T. A. Fktes ( F. S. 

 Drjil. Afjr., Bureau of Auiiuol IiuhiMry llul. ,7/, jip. ;;, ph. 2, dijnoi. 4). — I'sing a 

 respiration calorimeter of the Atwater-Rf)sa type, which they have constructed with 

 a number of modifications suiting it to experiments with large animal.^!, the authors, 

 in coojieration with the Bureau of Animal Industry of this Department, conducted a 

 series of experiments with a steer with the special object of determining the available 

 energy of timothy hay. Some of the essential features of the resjiiration calorimeter 

 are very briefly described. The accuracy of the apparatus was shown by check 

 experiments in which alcohol was l)urned in the respiration chamber. In one of 

 tliese in which 975.34 gm. of alcoliol was burned 99.1 jier cent of the theoretical 

 amount of carbon dioxid and 100.8 per cent of tlie theoretical amount of heat were 

 measured. Ecjually close results were obtained in the other check tests. 



The 4 jjcriods in which the experiment was divided each covered 2 days in the 

 respiration chamber. The ration consisted of timothy hay with a small j)roportion 

 of linseed meal, the energy being least in the flrst experimental ])eriod and greatest 

 in the fourth. Data regarding the incc.me and outgo of matter and I'uergy, the 

 amount of time the steer spent standing up and lying down, and other experimental 

 details are reported in full. 



In the author's opinion, for herbivora the results arc not in accord with the com- 

 monly accepted theory that as sources of energy the nutrients may replace one 

 another in j)roportion to their heats of combustion. As ])ointed out, isodynamic 

 replacement implies that there is no increase in heat production witli an increasing 

 amount of food. . . . The results obtained in the periods lu'low the maintenance 

 ration fully confirm this doubt. Only (53 per cent of the metabolizahle energy 

 served to prevent loss of tissue, while 37 per cent simply increased the heat i)roduc- 

 tion of the animal. In other words, the digestc<l matter of the liay was not isody- 

 namic with body tissue under the conditions of this experiment. Moreover, t/ie 



