26 STORRS AGRICULTURAL EXPERIMENT STATION 
tors and from eggs both from the College stock and from stock 
in different parts of the state, and nearly every chick died. 
About 500 were hatched in March, and none of these showed 
any symptoms of the trouble, nor have there been any symp- 
toms since. 
The incubator cellar has a chimney hole about three feet 
from the ceiling that has always been left open for ventilation ; 
but during February last it was necessary to have some heat 
in the room during the noon hour each day, and an ordinary 
cook stove was used. This Was taken down during the last 
week in February. During the time the stove was in use 
there was found to be about eighteen parts of carbonic acid 
gas in the room, as compared with nine parts a month later 
(after the stove was taken down). 
Another case was noticed where eggs from a neighbor’s 
stock were used. This neighbor has a very warm hen house 
and has had trouble with roup for several years. The eggs on 
one side of a tray were White Rocks from the College stock; 
the neighbor filled the other half of the tray with eggs from 
Barred Rocks. The chicks were allput in one brooder and 
only one case of bowel trouble was noticed in the white chicks, 
while all the neighbor’s died. This was caused, no doubt, by 
lack of vitality in the parent stock. 
While a large majority of the deaths are from the causes 
just mentioned, still, improper food seems to be an important 
factor. » : | 
_ In order that the effect of different feeds might be ascer- 
tained, the chicks from one incubator were divided among four 
brooders, all of the same construction and in the same build- 
ing. These flocks were fed different well known chick feeds, 
and in one pen the mortality was very high (see Table No. 14, 
p. 33), while in all four pens the average amount of food con- 
sumed by each chick was about the same. After a four days’ 
trial the feeds were changed, and the particular brand which 
was being used in the pen showing a great mortality apparent- 
ly caused a considerable increase in deaths in the second flock 
to which it was fed. About the ninth day the feeds were again 
