534 PRINCIPLES OF ANIMAL NUTRITION. 
puted in the previous paragraph. The difference is too great to be 
ascribed to experimental errors in estimating the small amount of 
work done, and can most reasonably be ascribed to the difference 
in the character of the ration. Apparently the horse, like cattle 
(p. 433), requires less digestible food for maintenance when the 
latter consists largely of grain than when it is chiefly or wholly coarse 
fodder. 
Direct experiments by Wolff * likewise show that the digestible 
nutrients of concentrated feed (oats) are more valuable for work 
production than those of coarse feed (hay). The experiments 
were made in the manner already described, the draft being uni- 
formly 60 kgs. Although the measurements of the work actually 
done are probably incorrect, it may be assumed to have been 
substantially proportional to the number of revolutions of the 
dynamometer. A ration of 3 kgs. of hay and 5.5 kgs. of oats served 
as the basal ration, to which was added in one case 4 kgs. of hay 
and in another 14 kgs. of oats. The nutrients digested in each 
case and the equivalent amount of work secured were: 
Digested. 
’ 55 
ao] Ration. Nitrogen-| Ether Total Se 
2 Protein, Fewie ree Ex- (Fat x | Se 
® Grms. 1ber, | Extract, | tract, 2.4), oo 
Ay Grms. | “Grms. Grms. Grms ae 
I-III | 7 kgs. hay, ee kgs: oats| 822.58 | 816.68 | 3889.64 | 186.72 | 5973.62 750 
Vi.) 3 “ 0 5.5 “ | 626.46 | 422.74 | 3068.46 | 184.78 | 4561.13 350 
4 kgs. hay........... 196.12 | 393.94 | 821.18 1.94 | 1412.49 | 400 
Per" 100 POVOUMIONS i. |4 ee neways dees ee e4e 04> akon bee 353.12 
VI...) 3 kgs. hay, 7 kgs. oats...! 754.52 | 355.24 | 3719.24 | 252.17 | 5434.21 700 
View [BP PERE “| 626.46 | 393.94 | 3068.46 | 184.78 | 4561.13 350 
1.5 kgs. oats........ 128.06 |—67.50 | 650.78 | 67.39 | 873.08 | 350 
Per 100 revolutions ..]........[........)ecc ccc ceufeeee eee 249.45 
The relative value of the digested matter of hay and of oats for work 
production in these trials was thus approximately as 5 : 7. 
In the earlier experiments (p. 531) it was found that when oats 
or starch were added to a basal ration, approximately 315 grams 
of digested nutrients were required to produce the amount of 
work represented by 100 revolutions at 76 kgs. draft. Converting 
this result and the one just given for oats into kilogram-meters, 
Wolff computes that 100 grams of digested nutrients was equivalent, 
* Loc. cit., pp. 84-95. 
