14 BULLETIN 953, U. S. DEPAKTMEISTT OF AGEICULTURE. 



upper half of the silo. This is only what would be expected when 

 it is considered that the ammonia nitrogen is a decomposition prod- 

 uct of the amino bodies and the longer stay in the silo gives more 

 time for such decomposition to take place. 



The amounts of amino and of ammonia nitrogen, expressed in 

 parts per million, do not follow parallel curves, although there is 

 a general rise and fall throughout the whole period of juice collec- 

 tion. The proportionate increase in the amount of amino nitrogen 

 is greater, as is also the later decrease. The ammonia nitrogen in 

 the first sample is nearly one- fourth as much as the amino nitrogen, 

 but as the amount of amino nitrogen increases much more rapidly 

 than the ammonia nitrogen it drops in the fifth sample to less than 

 one-fifth. The proportion remains at one-fiftli, or below, up to 

 the sixteenth sample and then slightly rises to the thirty-sixth sam- 

 ple. Here the amount of ammonia nitrogen decreases slowly and 

 the amount of amino nitrogen decreases rapidly; consequently, the 

 proportion of ammonia nitrogen to amino nitrogen in the last two 

 samples is raised to over one- fourth. 



The specific gravity ranges from 1.027 to 1.046 and the acidity 

 from an amount requiring 21.4 cubic centimeters to an amount re- 

 quiring 39.5 cubic centimeters normal alkali for 100 grams of juice. 

 The total nitrogen varies from 0.139 per cent to 0.323 per cent, and 

 the albuminoid nitrogen from 0.0112 per cent to 0.0496 per cent. 



The ammonia nitrogen ranges from 171.7 to 448.7 parts per million 

 and the amino nitrogen from 710 to 2,139 parts per million. 



It will be seen from the tables that the greater part of the nitrogen 

 present in the juice escaping from the silo is in the form of soluble 

 nonalbuminoid nitrogen compounds. Although the actual food value 

 of such compounds is still somewhat a matter of controversy, yet 

 it may be a matter of interest, from a practical standpoint, to ob- 

 serve the possible loss of food material caused by the escape of juice 

 these two* years. If the total nitrogen of the 2,679 pounds of juice 

 collected in 191^15 is expressed as pure protein, we have a loss 

 of 28.89 pounds, which represents the protein in about 1,500 pounds 

 of average silage. Expressing in the same way the results for the 

 season of 1915-16, we have a loss of 150.75 pounds in the 9,494.5 pounds 

 of juice collected, representing the protein in about 7,500 pounds of 

 average silage. 



On a technical basis the results of the two seasons' study of silage 

 juice may furnish some explanation for the large variations in the 

 losses of soluble silage constituents which are occasionally reported 

 by investigators. It shows how a large amount of juice, carrying 

 with it much soluble food material, may sink to the bottom of the 

 silo or easily be lost through cracks or through an earthen floor. 



