CONDITIONS INFLUENCING DIGESTION 127 



185. Influence of the stage of growth of the plant. 



Another generalization, which certainly must hold good 

 with reference to the digestibility of fodder plants, is that 

 any conditions of development which favor a relatively 

 large proportion of the more soluble carbohydrates, viz., 

 starches and sugars, and accompanied by a minimum of 

 gums and fiber, promote a high rate of digestibility, and 

 reverse conditions produce the opposite result. It is well 

 known that, in general, as the meadow grasses mature 

 the relative proportion of fiber increases and the tissue 

 becomes harder and more resisting. Numerous Ameri- 

 can and European digestion trials unite in testifying 

 almost unanimously to a gradually diminished digesti- 

 bility as the meadow grasses increase in age. The matur- 

 ing of maize seems to produce quite the contrary effect. 

 The testimony of experiments conducted at the Connec- 

 ticut, Maine, and Pennsylvania experiment stations 

 justifies the statement that the corn plant, cut when the 

 ears are full-grown, furnishes not only a larger amount 

 of digestible material, but a larger relative proportion 

 tha,n when cut before the ears have formed; and this is 

 strictly in harmony with our general principle, for the 

 mature plant, on account of the storage of starch in the 

 kernels, has by far a larger proportion of the more digesti- 

 ble carbohydrates. (See Par. 102.) 



186. Influence of methods of preparation of food. 

 Much labor and expense have been expended by farmers 

 in giving to feeding-stuffs special treatment, such as wet- 

 ting, steaming, cooking and fermenting, in order to 

 secure a supposed increase in nutritive value, an increase 

 which must come chiefly, if at all, from a more com- 

 plete digestion. It is plainly noticeable that these methods 

 of feeding have lost in prevalence rather than gained. 



