1094 
Journal of Agricultural Research 
Vol. XXXI, No. 11 
requirement for maintenance of these young animals, the net-energy 
estimations derivable from the results are withheld for the time being. 
Table 4 gives the maintenance requirements of net energy, as 
determined in the different periods, and the averages for the series. 
It should be noted that in averaging the maintenance requirements 
for the series of experimental periods only one value is given for two 
periods in those cases in which only two periods were the basis for 
determining the heat-increment value of the feed. This is done w 
because in such cases only one comparison is possible, and only one" 
heat-increment value, therefore, is obtained. The value for mainte¬ 
nance must be considered to be the same in the two periods. 
Table IV. — Maintenance requirements of net energy 
Ex¬ 
peri¬ 
Ani¬ 
Net energy required for maintenance 
ment 
No. 
mal 
In successive periods 
Average 
174 
I 
Cals. 
6,794 
6,( 
Cals. 
7,027 
>17 
i 
Cals. 
6,812 
Cals. 
6,855 
Cals. 
Cals. 
Cals. 
Cals. 
6,872 
179 
I 
6,619 
6,618 
a 6,981 
b 4,365 
b 4,692 
5,066 
5,457 
4,624 
3,802 
6,405 
186 
I 
200 
A 
200 
B 
207 
A 
4,925 
5,284 
4,887 
3,851 
6,592 
5,017 
4,270 
5,567 
5,1 
5,160 
5, il3 
5 . 552 
207 
B 
5,536 
4,900 
3. 
209 
F 
4,889 
3 . 879 
4,623 
4,037 
4,408 
210 
D 
211 
D 
6,067 
5 . 664 
6,416 
5,544 
3,672 
5,199 
6,546 
5,203 
4,238 
4,696 
211 
G 
5,357 
3,877 
5,004 
5,573 
7,094 
6,861 
212 
H 
3,428 
5,325 
>73 
4,342 
4,883 
3,312 
4,648 
216 
217 
J 
J 
4,712 
217 
<=J 
7.094 
220 
K 
6, ( 
>69 
6,688 
7,196 
1 
j 6,893 
• Computed from experiment 179. b Computed from experiment 207. c Fattened. 
VARIATIONS IN THE VALUES FOR MAINTENANCE 
An examination of the values for maintenance requirement of net 
energy in each of the series of experiments from which the averages 
are derived, shows that the differences are apparently due (Table 
IV) not to differences in kind of ration used (hay, or hay and grain), 
in the different periods of the same series, or to variations in live 
weight of the animal, but to accumulated errors of work. Thus, in 
experiment 211 the maintenance requirement of net energy for 
steer D seems to be less in Periods II # and III, on hay and grain 
rations, than in the other periods in which hay alone was fed, while 
the maintenance requirement of steer G appears to be greater in the 
hay and grain periods than in the hay periods. In experiments * 
209, 216, and 220, the maintenance requirements computed from the 
hay and grain rations are, in general, greater than those computed 
from the hay rations, but in some of these the differences are only 
slight. In experiment 212 the maintenance requirements computed 
from the alfalfa meal rations (Periods II, IV, VI) are considerably 
less than those computed from the alfalfa hay rations (Periods I, 
III, V). These differences can hardly be due to difference in kind of 
feed. As to the possible effect of variations in the live weight of 
the animals, in the different periods, on the results of the computation 
