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of the common feeding stuffs in the group are wholesome and valuable 

 for horses. If any one of these feeding stuffs is substituted for oats, 

 which may be taken for a standard, the substitution should be propor- 

 tional to the composition of the two feeds and not pound for pound. 



FORAGE CROPS, FRESH AND CURED. 



The various forage crops — grass, clover, Kafir corn, corn, etc. — all 

 have a high water content; that is, they are more or less succulent 

 and juicy. They contain, however, considerable nutritive material, 

 usually protein and carbohydrates, and are valuable feeding stuffs. 



The leguminous forage crops— alfalfa, clover, cowpeas, soy beans, 

 vetch, etc. — are richer in protein than the grasses. When the forage 

 crops are dried and cured the resulting hay is richer in proportion to 

 its bulk than the green material; in other words, it has been concen- 

 trated by the evaporation of the greater part of the water present. 

 However, this is not the only change which has taken place. When 

 hay is properly cured it undergoes a peculiar sort of fermention or 

 oxidation which materially affects its composition. 



As shown by recent investigations, fermentation improves the hay 

 by diminishing the quantity of crude fiber and by increasing the rela- 

 tive amount of other nutrients, especially nitrogen-free extract. The 

 greater the fermentation the more the crude fiber is diminished, and 

 this is especially marked when ha}^ is dried on racks. Hay which has 

 undergone proper fermentation has a better flavor and agrees better 

 with animals and is apparently more digestible than hay which has 

 dried quickly in the sun without fermentation. 



The feeding value of different forage crops, fresh and cured, depends 

 in considerable degree upon the stage of growth, as has been shown 

 by a number of chemical studies of the composition of different crops 

 and cuttings of alfalfa, young and more matured corn forage, etc. 

 Generally speaking, the nutritive value of the crop increases until 

 growth is complete and diminishes somewhat as the plants mature or 

 become overripe. Straw, the fully ripened stalk of cereal grains, 

 contains some nutritive material, but is less nutritious than the same 

 portion of the plant cut before ripening. In the perfectly ripe con- 

 dition the nutritive material, elaborated in different portions of the 

 ordinary forage plants, has been largely conveyed to the seed and used 

 for its development or stored as reserve material. 



Green forage crops are frequently preserved by ensiling. In this 

 process the material undergoes a peculiar oxidation which correspond- 

 ingly changes it in composition and food value. Some of the carbo- 

 hydrates are changed into alcohol, acetic and other acids, and crude 

 fiber is undoubtedly softened somewhat, and possibly the silage is thus 

 rendered more digestible. Bodies having peculiar flavor and odor are 

 also formed. 



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