2 BULLETIN 561, U. S. DEPARTMENT OF AGRICULTURE. 
have been added each year subsequently, and the original pens are 
still being kept to study the effect of the feed and of the age of the 
fowls on egg production. The results secured in 16 pens, containing 
366 fowls, are given in this bulletin, including three complete years' 
work of the first six pens. The work was conducted on the experi- 
mental farm of the Bureau of Animal Industry, near Beltsville, Md. 
Prices of individual grains in 1917 are from 20 to 100 per cent 
higher than the prices used in this bulletin, which should be care- 
fully considered in estimating the present cost of egg production. 
DESCRIPTION OF STOCK AND CONDITIONS. 
Most of the feeding tests were started with 30 standard-bred 
pullets, bred and reared on the farm under the same conditions, and 
selected for vigor, standard shape, and color. Some of the flocks 
consisted of fowls of one breed, while others contained more than one 
kind of pure-bred fowls of the general-purpose type in the same flock, 
including Barred Plymouth Rocks, White Wyandottes, Rhode 
Island Reds, and Buff Orpingtons (see Plates I to IV). Pens 10 to 
14, inclusive, also contained some cross-bred pullets. These flocks 
were housed in colony houses similar to those shown in Plates III and 
V. The house shown in Plate III is 10 feet long by 7 feet wide, and 
that in Plate V is 6 feet long by 5 feet wide; both houses are described 
in detail in Farmers' Bulletin 574 of this department. A better 
average result is secured by using 30 fowls in each pen than is ob- 
tained from smaller flocks, as the effect of any variation due to 
individuals is reduced greatly. Except three pens which were con- 
fined to good-sized yards, all the fowls were allowed free range over 
several acres of rough land, part of which is in woods and the rest is 
covered with grass and weeds. The soil is a heavy clay, which does 
not drain freely. 
Table 1. — Pens, rations, and conditions. 
Feed. 
Pen 
Date experi- 
ment began. 
Number 
of pullets. 
Breed. 
How kept. 
No. 
Scratch mixture. 
Mash. 
1 
Nov. 1,1912 
30 
Rhode Island Reds. . 
Free range . . 
J cracked corn, i 
wheat, § oats. 
i bran, \ middlings, 
i corn meal, \ 
beef scrap. 
2 
do 
30 
21 White Wyan- 
dottes, 6 Buff Or- 
pingtons, 3 Barred 
Plymouth Rocks. 
do 
£ cracked corn, 
£ wheat. 
Same as for Pen 1. 
3 
do 
30 
14 Buff Orpingtons, 
Yarded 
Same as for Pen 
Bran, middlings, 
corn meal, and 
16 Rhode Island 
1. 
Reds. 
beef scrap, each 
in separate hop- 
pers. 
Same as for Pen 3. 
4 
Jan. 18,1913 
30 
White Leghorns 
Free range.. 
do 
5 
do 
30 
19 Barred Plymouth 
Yarded 
do 
9 per cent bran, 9 
Rocks, 2 White 
per cent mid- 
Plymouth Rocks, 
dlings, 63 per 
6 Rhode Island 
cent corn meal, 
Reds, 3 Buff Or- 
19 per cent beef 
pingtons. 
scrap. 
