APPETITE OF SWINE 
397 
acids in the natnral feeds increase their consumption over and 
above normal, that is over what these same pigs would have 
eaten had they been given an abundance from the beginning. 
That there is a gradual and steady decline after the first 30 
days in the ‘‘appetite” protein requirement is evident. This 
decline, however, after the pigs reach 240 days of age is not 
very marked, and from the 300th to the 355th day there is but 
a slight decrease, or about one-tenth the decline in actual 
amounts per unit weight that is noticeable between the 140th 
day and the 190th day. This probably indicates that the pigs 
have passed the period of maximum growth per unit of live 
weight, — which indication is borne out by the visual observations 
as regards increase in weight, height, length, and breadth of 
the animals under consideration. 
The crude carbohydrate equivalent consumed daily to a 
thousand pounds live weight is given in Plate XLIII. The strik- 
ing features of this chart are : 
1. The marked similarity and coincidence of the curves of 
the three “free-choice system” or “appetite’^ fed lots. 
2. The “period of readjustment” in the first thirty days of 
feeding. 
3. Fairly close agreement of the Dietrich Illinois standard 
with the “appetite” curve when the pigs increase in age from 
80 to 160 days; after which time, however, this standard calls 
for carbohydrate nutrients in excess of those actually eaten. 
4. The gradual natural decline in carbohydrate equivalent 
consumption from the 160th day of age until the pigs are prac- 
tically a year old. This decline is most marked after the pigs; are 
a little more than five months of age, thus indicating that early 
in life the consumptive ability kept pace with the increase in 
weight. After the first five months of life, however, the capacity 
(as indicated by the amount eaten) did not enlarge proportion- 
ately as rapidly as the weight increased. 
5. The relatively low requirement of the Wolff -Lehmann 
standard until the pig reaches seven months of age as contrasted 
with the “appetite” curve (or even the Dietrich standard re- 
quirement). The high comparative Wolff-Lehmann requirement 
after seven months is much greater than the “appetite,” fully 
satisfied from the beginning, demands. Judging these curves 
from the standpoint of reasonability it would seem that the lines 
