CONSERVATION OF FEEDING-STUFFS 125 



in the stack with the organic matter, and above all 

 the activity of different varieties of bacteria, which 

 very soon develop prodigiously. In small stacks, 

 the water is quickly got rid of owing to the high 

 temperature, but in larger stacks it cannot escape 

 so quickly, and so fermentation continues for a 

 longer period. This means a greater loss of material 

 than in a small stack. Experiments have shown 

 that whilst in a small stack the loss of dry matter 

 was 14-2%, in a stack double the size the loss was 



30%. 



The losses fall principally upon the nitrogen-free 

 extract substances, but the proteins also suffer. 

 The former are completely decomposed, whilst the 

 latter pass partly into non-protein matter and 

 partly into an indigestible form. The higher the 

 temperature rises during the making of the hay, 

 and the darker the colour of it is, the less digestible 

 are the proteins found to be. By means of artificial 

 digestion experiments it was found that of the 

 crude protein in the meadow grass 86-5% was 

 digestible when the hay made from the grass was 

 light brown in colour, when it was dark brown 75-1 %, 

 when black 2-6% only. 



(2) Sour fodder and silage. 



For the preparation of sour fodder the leaves and 

 tops of root crops, green maize, potatoes, mangels, 



