36 
N". C. Agricultural Experiment Station 
Of six Barred Plymouth Rock hens starting on peanut meal one-third and corn 
meal two-thirds, five, or 83 percent, finished. 
Of six Barred Plymouth Rock hens starting on soybean meal one-third and corn 
meal two-thirds, five, or 83 percent, finished, thus placing both soybean and peanut 
meals high from a tolerance standpoint. This corresponds with our many practical 
feeding tests with these two feeds. 
Of six Partridge Plymouth Rocks starting on twenty percent dried buttermilk and 
eighty percent corn meal, five, or 83 percent, finished. 
Of six Buff Plymouth Rock hens starting on 20 percent dried blood and 80 percent 
corn, four, or 66 percent, finished. 
Of six White Plymouth Rock and Buff Orpington hens starting on digester 
tankage 20 percent and corn meal 80 percent, two, or 33 percent, finished. This cor¬ 
responds to our various series of practical feeding tests that digester tankage, at least 
some batches, is hard on fowls. 
Of six White Plymouth Rock hens starting on beef scrap and bone meal one-third 
part and corn meal two-thirds part, two, or 33 percent, finished. 
In a study of these tests it appears that of 105 hens that started the various tests, 
but 48 or 45.7 percent, finished the test. Of the 79 started on two feeds, 53, or 67.4 
percent, finished the test. From a tolerance standpoint the odds are in favor of more 
than one feed against the single feed. 
SUMMARY OF THE DIGESTIVE COEFFICIENT STUDIES 
In a review of research literature we find but eighty-nine individual digestion 
coefficient tests with poultry. To this we have added 101, making 190 tests to date. 
The digestion coefficients with poultry were studies on nineteen feeds. In the case 
of wheat middlings two series of tests were run with middlings alone and one m com¬ 
bination with unbolted corn meal. Since wheat middlings alone tends to cause 
looseness of the bowels, it was the desire to determine if this in any way influenced the 
accuracy of the work. To test this point a series of experiments were run with a 
combination of wheat middlings and unbolted corn meal. In the case of wheat mid¬ 
dlings alone the average digestible organic matter is shown to be 47.72 percent and 
56.19 percent with an average of 51.95 percent, while in combination with corn 
meal the percentage digestible organic matter was 59.78 percent. 
In the experiments with corn meal one series of trials was run with bolted and anoth¬ 
er series with unbolted meal. 
Not only did the birds stand up better under more than one feed but apparently 
one feed favored the increased digestion of the other feed. Some of the feeds, as rye 
and middlings, if given in their pure form cause irritation of the bowel and looseness 
and still others, especially those of the animal products group, as digester tankage, 
meat and bone meal, blood meal, dried buttermilk, and fish meal are so concentrated 
that it is necessary to give them with other feeds in the digestive tests. In our work 
we used unbolted corn meal as shown in the tables. Digestion tests had previously 
been run with the corn meal to determine its digestibility. 
Crost in 1900 gave as his results that the crude protein of barley and rye was more 
digestable than that of oats. We cannot confirm this result as in two tests with barley 
72.77 percent of the protein was digested, while in three tests with rye there was 71.85 
percent digested and in six tests with oats there was 73.49 percent digested or slightly 
greater digestion of protein in oats than in either barley or rye, which is the reverse 
of his findings. Crost further states that the crude fiber of barley and oats was 
absorbed to a slight degree, but more in the case of rye. In our case 4.33 percent fiber 
