APPETITE OF SWINE 
391 
PERCENTAGE COMPOSITION OF RATIONS BY PERIODS. 
Ten Day 
Period 
03 
B 
9 
bfl 
<1 
Feeds in a Hundred Pounds Eaten 
Com Grain 
Whole Oats 
Meat Meal 
Oil Meal 
1 
Charcoal 
Limestone 
Salt 
3rd 
. 108 
76.58 
6.42 
13.38 
3.33 
.10 
.16 
.02 
10th 
. . 178 
93.66 
None 
5.96 
.35 
None 
None 
.02 
18th 
. 258 
99.47 
None 
.15 
.05 
.10 
.07 
.16 
25th 
. 328 
94.42 
None 
3.27 
.03 
2.25 
None 
.03 
The striking feature of these tabulated data is that they 
show the very marked changeableness of the pigs’ appetites as 
manifested by what they eat throughout the period of growth 
and fattening. When the animal is young there is a great de- 
mand for high protein feeds, during which time we note that the 
proportion of meat meal (in comparison with corn, a “carbo- 
hydrate-fat” feed) is very high. After a time, however, when 
the growth impulse begins to slacken and the inherited specifi- 
cations, in so far as growth is concerned, are quite largely taken 
care of, the amount of meat meal in the ration gradually de- 
creases until it reaches a low point at about the age of 255 days 
(see Plate XLI) , at which time it gradually begins to increase. It 
is to be noted in this connection that the corn, which has been 
furnishing most of the protein (practically all of it from the 
223d to 303d day), is consumed after the 223d day in rapidly 
decreasing quantity, thus making it necessary for the pigs to in- 
crease the amount of high-protein meat meal eaten if the total 
protein intake is to be kept from diminishing markedly. Thus 
the increase in meat product is due primarily to the limitation 
of capacity on the part of the pig, which makes it necessary 
for him to eat more, as well as a larger per cent of meat meal, 
if he would keep up the protein per unit weight in his ration 
daily. In other words, with the capacity for feed lessened it is 
quite necessary to increase the richness of the mixture in pro- 
tein in order to secure the requisite amount of this complex 
“amino-acid mixture” constituent. Reference to Plate XLII 
clearly shows that the actual amount of protein eaten to a thou- 
sand pounds live weight continually decreases in spite of the fact 
that the richness in protein of the mixture eaten has been in- 
