Digestive Coefficients of Poultry Feeds, etc. 
19 
GROSS AND CHEMICAL ANALYSES OF THE EXCRETA 
The droppings were reduced to fineness by grinding or by beating in a large iron 
mortar with a large iron pestle. The material was then passed through a wire sieve 
with 256 meshes to the square inch. 
In a gross study of this material there was observed grit consisting of quartz or 
silica, varying in size up to 2 x 4.5 m.m. and weighing 0.0813 gm. 
Black bodies were also observed and under the hand lens they were recognized as 
pieces of cinders. One piece of glass was observed in one study. These birds had not 
been given grit for the entire period they were used. This includes the four prelimin¬ 
ary days and the four test days in which the droppings were saved. Other bodies 
recognized included undigested feed. Chalk-like bodies, the largest of which measured 
2x3x4 mm. and weighed 0.0112 gm, consisted of urinary sediment and mostly of 
uric acid. In three tests the average weight of coarse parts was 0.0931. The percent¬ 
age of foreign matter was 0.56. 
Pig. 8. A Photograph Showing the Foreign and Other Hard Bodies of the excreta 
Which Resisted Grinding or Maceration and Was Removed by Aid of the Sieve 
1. Grit or quartz. 
2. Pieces of c'nders. 
3. Masses of hard uric acid crystals. 
4. Masses of undigested middlings. 
Chemical Analyses of Excreta 
The methods used in determining the moisture, ash, ether extract, crude fiber, 
nitrogen-free-extract, and total nitrogen are the same as those used in the feed ana¬ 
lyses. 
Determination of Free Ammonia 
Place 0.7 gm. of the excrement in a Kjeldahl flask with 200 cc. of water and 5 gms. 
of magnesium oxide free of carbon dioxide. Then connect the flask with a condesner 
and distill 100 cc. of the liquid into standard acid, titrate and calculate the ammonia 
present. 
