70 Report of Department of Animal Husbandry of the) 



Special analyses were made of all the foods. The coefiScionts 

 of digestibility used in the calculations wore the averages from 

 American determinations when several were to be found, but 

 many of them were from European data. These calculations 

 were made several years ago when factors from recent investiga- 

 tions were not available. The coefficients used differ somewhat 

 from the latest averages but not enough to have a recalculation 

 affect the general results. In Table A are given those used for 

 the several foods. 



Selecting records from a system of feeding conforming to other 

 purposes did not permit an absolute uniformity in all relations 

 essential to a direct and unqualified comparison of the different 

 rations. The averaged groupings are therefore not by any means 

 satisfactorily complete and full, although the volume of testimony 

 in a degree compensates for some of the lack of uniformity. 

 While a large number of records may cover one change in a 

 ration, there may be comparatively few that afford data con- 

 cerning some corresponding change, desired for comparison, so 

 that in this respect also undesirable irregularity exists. Evi- 

 dence only of the immediate, or perhaps stimulating, effect of 

 the modified rations is offered. There is taken into consider- 

 ation no intermediate period to permit full adjustment to the 

 changed food, and the efficiency of the different rations for sus- 

 tained milk production over longer periods is not shown. The 

 record is taken for from two to four weeks before a change in a 

 ration and for about the same time immediately following. 



Table A. — Average Coefficients of Digestibility. 



ProtPin. 



Whoali bran 78. 



Cornmcal ■ 76. 



Ground oats 78. 



Wheat middlings 82. 



O. P. linsoed meal 86. 



Cottonseed meal 89. 



Gluten meal 87. 



Gluten feed 86. 



N. P. linsood nioal S7. 



Brewers' grains 71. 



