ANIMAL PRODUCTION. 269 



Coefficients of (lif/cstibility of »i1rogcn-free extract and crude fiber. 



" The quantity of residue digested was less than the quantity digested from the basal 

 ration. 



The author studied the material removed by cold- water from the feces in 

 three of his experimental periods and found that something over 3 per cent 

 was soluble, " of which approximately one-third was ash, something over one- 

 fhird was protein, and less than one-third nonprotein organic matter. About 

 10 per cent of the total protein, 20 per cent of the total ash, and 3 per cent of 

 the nitrogen-free extract were soluble in water. 



" While the above facts are of some interest it was not considered of im- 

 portance to pursue the investigation further." 



The author's summary and conclusions follow : 



" The ration of cotton-seed meal and hulls fed in this experiment was digested 

 to a mucli greater extent than the calculated digestion from average figures. 



" The nutrients of the grain of Kafir corn and milo maize are somewhat less 

 digestible than the corresponding nutrients in Indian corn. 



" Indian corn has about 10 per cent greater value for feeding than Kafir corn 

 or milo maize. 



" The nitrogen-free extract of molasses is highly digestible. 



"The productive value of different classes of feeds as measured by the fat 

 produced, is not in proportion to their digestible constituents. 



" Increase in crude fiber in a feed means a decrease in productive value. 



" Sugars are digested 92 to 100 per cent, even when the reducing materials 

 in the excrement are considered to be sugars. 



" The apparent starch of cotton-seed hulls, which can not be true starch, 

 though dissolved by diastase, has a low digestibility. 



" The starch of Kafir corn and milo maize is almost completely digested. 



"Although the nitrogen-free extract of milo maize and Kafir corn is com- 

 posed almost entirely of starch, the nitrogen-free extract was digested to a much 

 less extent than the starch. This difference is probably due to a depression of 

 digestibility of the nitrogen-free extract of the meal and hulls. It appears 

 possible that the nitrogen-free extract of starchy feeds is digested to a greater 

 extent than is shown by digestion coefficients. 



"It appears possible that crude fiber undergoes changes within the animal 

 which render it soluble in acid or alkali and therefore a portion of the nitrogen- 

 free extract. 



