THE DIGESTIVE COEFFICIENTS OF POULTRY 
FEEDS AND RAPIDITY OF DIGESTION 
AND 
FATE OF GRIT IN THE FOWL 
By B. F. Kaupp and J. E. Ivey, North Carolina Experiment Station, 
Raleigh, N. C. 
HISTORICAL REVIEW 
The absence of definite standards and coefficients of digestibility of different feeds 
for poultry lias been a serious drawback to the best work of practical feeding tests. 
The alimentary canal of birds is quite different from that of mammals and it is 
desirable to determine if there is any difference in digestive coefficients between fowls 
and mammals. The fact that the undigested parts of the food and the urinary 
excretions are eliminated from the body together makes a serious obstacle in the way 
of protein digest ion determinations with fowls and greatly increases the amount of 
analytical work to be done. 
Some digestive! experiments with poultry were done by Bartlett 1 . The length of 
time of feeding in these experiments was twelve to fourteen days, being divided into 
two periods, a preliminary period of five to seven days, when the amount the bird 
would eat was determined and the alimentary canal freed from other food, and a col¬ 
lection period. The droppings were collected in a specially constructed bag attached 
to the posterior parts of the bird and held in place by a kind of harness. The feeding 
was done at regular hours morning and evening. The droppings were collected 
at the same time and placed in glass jars and kept covered with alcohol to 
prevent fermentation. Later the alcohol was evaporated off on a steam bath, then 
dried at 00 degrees C. to air dry conditions. 
Bartlett concludes after conducting his feeding experiments with different rations 
that “the indications are that the digestive coefficient of most nutrients for poultry 
are not materially different from other animals”. “Unlike ruminants they digest 
very little crude fiber, hence coarser fodder carrying much of this material is of but lit¬ 
tle value. The nutrients of wheat do not seem to be as well handled as most other 
concentrated grains, the ether extract showing a particularly low coefficient. Like¬ 
wise bran, one of the wheat by-products, shows low digestibility in organic matter 
including ether extract and nitrogen-free-extract. Its bulky and coarse condition has 
brought it much into favor to feed with more concentrated materials and it often 
makes as much as fifty per cent of the mixture used in mashes.” 
“The mixture of equal parts corn meal and fine cut early clover is sufficiently 
bulky to feed with concentrates and is more digestible. An exclusive diet of wheat has 
a deranging effect upon the digestive system of the birds.” He further concludes 
that corn is the most valuable grain for poultry, being high in digestibility and palati- 
bility. 
The feeds tested were wheat bran, corn meal, gluten feed, beef scrap, linseed meal, 
corn, cracked corn, cut clover, oats, rolled oats, wheat both hard and soft. 
1 Bartlett,*J. M., Digestive Experiments with Poultry, Bui. 184, Me. Exp. Sta., 1910. 
