24 
INDIVIDUAL VARIATION IN FATTENING CHICKENS. 
A study of Table 12 and of the variation in the summaries of the 
feeding experiments at the different stations shows that many fac- 
tors affect the gains in fattening. Variation within a lot is due some- 
what to the difference in the weight of the birds, but largely to the 
difference in the ability of the individuals to take on flesh under the 
existing conditions. This plainly shows how much variation exists 
in this ability to fatten readily, and the influence which the weather 
has in fattening. The possible error of conclusions drawn from small 
lots in fattening experiments is readily noted, and this possibility 
undoubtedly occurs under other poultry methods, as in the influence 
of feed and housing on the production of eggs. The marked effects 
of weather on fattening demonstrates the error which may occur in 
direct comparison of fattening tests conducted at different periods of 
the year, or in different seasons. 
Table 12. — Individual variation in fattening chickens. 
Average weight. 
Num- 
Per cent gain. 
Number 
of head . 
Kind. 
ber of 
days 
High. 
Low. 
fed. 
High. 
Low. 
Average. 
Pounds. 
Pounds. 
Per ct. 
Per ct. 
Per ct. 
1,790 
Roasters. . 
4.19 
2.58 
8 
36.4. 
4.5 
13 
1,400 
...do 
3.07 
2.53 
8 
25.9 
7.6 
14 
1,216 
...do 
3.05 
2.70 
8 
27.0 
9.0 
14 
1,880 
Springs 
2,03 
1.43 
15 
55.0 
17.0 
27 
1,080 
...do 
1.95 
1.62 
14 
63.0 
18.0 
29 
768 
Broilers... 
1.89 
1.69 
14 
56.0 
12.0 
36 
320 
...do 
1.75 
1.23 
14 
45.0 
36.0 
39 
600 
...do 
1.65 
1.50 
14 
53.0 
18.0 
38 
480 
...do 
1.76 
1.40 
14 
39.0 
31.0 
35 
320 
...do 
1.75 
1.61 
14 
43.0 
25.0 
41 
1,024 
Springs 
3.55 
2.72 
11 
29.0 
7.0 
18 
512 
Broilers . . . 
1.47 
1.34 
15 
63.0 
31.0 
44 
1,088 
Springs — 
2.28 
1.11 
13 
67.0 
11.0 
35 
768 
..fdo 
1.58 
1.47 
14 
45.0 
. 30.0 
37 
In the above work individual records were kept of each battery 
containing 64 birds. The variation in average weight and in per 
cent of gains was between batteries of birds fed under the same con- 
ditions. The great variation in birds fattened under the same con- 
ditions suggests the economical possibility of rejecting certain birds 
in fattening. A very small per cent of birds called "rangers" were 
graded out of the receipts at Station 1 and killed without fattening. 
These birds consisted of black and feather legged stock, Leghorns, 
and birds out of condition. All black and feather legged birds were 
kept separate at Station 4 and fed only for a short period during the 
early part of the feeding season. Much better results could be 
secured in the fattening stations if only the best birds were selected 
for fattening, although this would require extra skilled labor for 
selecting, and involve a different and more complicated system of 
handling the birds at the packing house. 
