THE CHEMICAL COMPOSITION OF FEEDINGSTUFFS 17 



same plant are greatly unlike. It is usually most abundant 

 in the stem, with less in the foliage, and least in the seed. 

 In the grains and seeds, the seed coats consist largely of 

 cellulose, while but Httle is found in the interior. Cellulose 

 is never foimd in the animal body. 



Familiar forms of crude fiber are paper, made from the 

 fiber of straw, flax, wood, or hemp ; cloth, made from the 

 fiber of cotton, flax, etc. ; and rope, made from the fiber of 

 hemp. 



Crude Fiber in Feedingstufifs. — The crude fiber in feed- 

 ingstuffs is determined by removing all other substances, 

 in so far as possible, by boiUng a w^eighed sample of the feed 

 in dilute acid, then in dilute alkah, and then washing it 

 with water, alcohol, and ether. The residue, consisting of 

 crude fiber and ash, is dried and weighed. It is then 

 ignited, and the ash is weighed. The weight of the ash 

 deducted from the weight of the total residue represents 

 the weight of crude fiber. The weight of the original 

 sample divided into the weight of the crude fiber and 

 multiplied by 100 gives the percentage of crude fiber in 

 the feedingstuff. 



The average percentages of crude fiber in the various 

 classes of ordinary feedingstuff s are shown in Table 5. It 

 is especially abundant in the husks of grains and seeds, as 

 barley, oat, and cottonseed hulls, — 40 to 46 per cent, and 

 in straws, hays, stover, and fodder, — 20 to 45 per cent. 

 Inasmuch as the percentage of crude fiber is higher in mature 

 than in immature plants, the late cut roughages contain 

 more crude fiber than early cut roughages. The cereal 

 grains and most of their by-products contain a relatively 

 small amount, — 1 to 12 per cent, while feedingstuff s of 



