162 



THE CHEMISTRY OF THE FARM 



diminish the digestibiHty.^ Hay appears to lose some 

 of its digestibihty by keeping. In hay which has 

 become brown by heating, the digestibihty of the 

 albuminoids, and of the soluble carbohydrates, is 

 diminished, while the digestibihty of the fibre is 

 increased. 



In silage the digestibility of the albuminoids is also 

 seriously diminished. Wolff cut meadow grass early 

 in October, dried a part, and constructed with the 

 remainder a silage stack. The grass was tolerably 

 dry, and no leakage from the stack occurred. In 

 March and April the dried grass and the silage were 

 consumed by sheep. The digestion coefficients found 

 were as follows : — 



The albuminoids in the silage thus appeared to be 

 almost indigestible ; the amides only were taken up by 

 the sheep. Similar, though less striking, results have 

 been obtained by other experimenters. 



Influence of one Food on the Digestion of another. — 

 If to a diet of hay and straw, consumed by a ruminant 

 animal, a pure albuminoid^ as wheat gluten, be added, 



' Thougli the digestibility of the hay may be nearly the same as 

 that of the original green fodder, the labour required to digest the 

 hay will be greater, and its value for the production of work and 

 increase will therefore be somewhat diminished. 



