THE UTILIZATION OF ENERGY. 459 
Cals. over Period 4, however, it was computed that 119.4 Cals. were 
due to an increased consumption of the ingredients of the basal 
ration, leaving 8504.8 Cals. as the metabolizable energy of the 
added hay. This 119.4 Cals., however, contributed to the increased 
gain of 3640.0 Cals. made by the animal. If we assume the per- 
centage 58.9 just computed to apply to it, the corresponding gain 
would be 119.4 X 0.589 or 70.3 Cals., leaving 3569.7 Cals. as the 
gain produced by the 8504.8 Cals. of metabolizable energy derived 
from the meadow hay. 
In Period 7, however, the animal weighed 736.0 kgs., and his 
computed maintenance requirement was therefore 14,909.6 Cals. of 
metabolizable energy, or 920.5 Cals. more than in Period 4. In 
other words, if he had weighed no more in Period 7 than in Period 
4, there would have been 920.5 Cals. more metabolizable energy 
which could have served to produce a gain of tissue. Assuming, as 
before, that 58.9% of this would be stored in the body, the result- 
ing gain would have been 920.5 X 0.589 or 542.2 Cals. Adding this 
to the gain of 3569.7 Cals. just computed makes a total of 4111.9 
Cals. as the computed gain to be credited to 8504.8 Cals. of metab- 
olizable energy in the hay added, which is equivalent to a per- 
centage utilization of 48.4 per cent. Expressed in tabular form, 
the results of these comparisons are as follows :— 
s 
=| ee 
a "8p .| Com- | Excess | Energy| £9 2 
Ey Z| Fou gone puted | over | of Gain : a3 
le See Energy Mainte- | Mainte-| (Cor- | o.8% 
ala ze Cale.’ | nance, | nance, |rected),| 24 
3 . Cals. Cals. Cals. | 25S 
Meadow Hay, VI: 
Basal ration + hay........ H| 7] 736.0 
26,013 .0} 14,909.6] 11,103 4] 5,643.2 
—119.4 
Correction for organic matter —119.4) —70.3 
25,893 .6 10,984 .0) 5,572.9 
Correction for live weight ... +920.5/+542.2 
11,904.5)6,115.1 
Basal ration............6-- H| 4| 668.9 | 17,388.8] 13,989.1} 3,399.7| 2,003.2) 58.9 
Difference.............-+ 8,504.8 8,504.8) 4,111.9) 48.4 
Table VII of the Appendix contains the details of the computa- 
tions of percentage utilization according to the above method. 
The results differ somewhat from those reported by Kellner,* 
* Loc. cit., pp. 63, 133, 226, and 334. 
