CHAPTER XLVI 



BACTERIA IN THE PREPARATION OF HAY 

 AND OTHER FODDERS 



The preservation of animal foods on the farm is 

 made effective by the removal of water from plant sub- 

 stances until the amount of moisture left in them is 

 no longer sufficient for the growth of bacteria. Hay, 

 straw and corn fodder are thus preserved for the future 

 needs of the animals by drying. However, even with 

 these substances, the water may not be removed rapidly 

 enough to check bacterial decompositions. 



Freshly cut grass gathered in heaps shows a rise in 

 temperature that may be high enough at times to cause 

 serious deterioration in its value as an animal food. 

 As the temperature of the grass in the interior of the 

 heap gradually rises, the number of bacteria increases 

 until the heat is too great for all except the most resis- 

 tant forms. Later, even these are destroyed and the 

 material becomes practically sterile. The question at 

 once arises whether the organisms have anything to 

 do with the heating of the grass or of other vegetable 

 materials placed in heaps. Bacteriologists are not yet 

 fully agreed as to the part played by microorganisms 

 in this process. Some even go so far as to assert that the 

 elevation of temperature may be accomplished without 



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