THE GROWTH OF CHICKENS IN CONFINEMENT.* 
By THOMAS B. OSBORNE anp LAFAYETTE B. MENDEL. 
WITH THE COOPERATION oF Epna L. FERRY AND ALFRED J. WAKEMAN. 
(From the Laboratory of the Connecticut Agricultural Experiment Station 
and the Sheffield Laboratory of Physiological Chemistry in Yale 
University, New Haven.) 
Pirates 4 To 6. 
(Received for publication, January 10, 1918.) 
The possible advantage in the use of chickens as experimental 
animals in the study of growth and other problems of nutrition 
has suggested itself to many investigators since the days of Pas- 
teur. These birds can be hatched under artificial conditions; they 
grow rapidly and therefore may furnish desired evidence more 
speedily than is the case with most of thedomestic animals; and 
furthermore if the conditions under which chickens continue to 
grow normally in confinement can be learned, it will be possible to 
obtain much information of practical use in poultry husbandry. 
There is a widespread belief among poultry raisers that young 
chickens cannot be reared under the artificial conditions of hous- 
ing and diet which many other experimental animals tolerate 
without detriment. The current ideas are expressed in the state- 
ments that the birds must be kept ‘‘on the ground,” that they 
must have exercise, outdoor life, and green food. In a recent 
report of observations upon the growth of young chickens under 
laboratory conditions Drummond? wrote: 
‘‘There are not many published records of the use of young chickens as 
the experimental animals in studies upon the factors concerned in growth 
and nutrition, but, from a reference to those of recent date, the present 
author was led to believe that one migby rely to, some considerable extent 
upon their suitability for such studies.’ 
* The expenses of this investigation were shared by the Connecticut 
Agricultural Experiment Station and the Carnegie Institution of Wash- 
ington, D. C. 
1 Drummond, J. C., Biochem. J., 1916, x, 77. 
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