FOODS. 81 



feeding the animals on these foods alone ; the digestibility 

 of the foods in the upper division has been found by 

 supplying them in various proportions along with hay, the 

 digestibility of which had been already ascertained with 

 the same animal. The amount of fibre in these last- 

 named foods is usually too small for its digestibility to be 

 determined with certainty by a few experiments. 



The concentrated foods placed in the upper part of the 

 table are seen to be far more thoroughly digested than 

 is the case with hay or straw. When of good quality, 

 80 or 90 per cent, of the organic matter of these foods 

 will be assimilated by the animal, except in those cases 

 where much fibre is present. The albuminoids and fat 

 in these foods have especially a greater digestibility than 

 the same ingredients in hay and straw. The hard fibre 

 forming the husk of seeds is apparently but little diges- 

 tible. The oats employed were of somewhat inferior 

 quality. 



In the case of ordinary hay and straw the organic 

 matter digested is but 45 to CO per cent, of that supplied. 

 The minimum amount digested occurs with wheat straw ; 

 oat straw, which is generally cut somewhat more green, is 

 distinctly more digestible. The results given for meadow 

 and clover hay relate to hay of average quality; the 

 lucerne hay was of better quality, and shows a much 

 higher degree of digestibility in the nitrogenous matter. 



The higher is the proportion of nitrogenous matter in 

 hay and straw, the greater appears to be its digestiblity. 

 Thus the wheat straw experimented with contained 4.8 

 per cent, of nitrogenous matter in its dry substance, of 

 which only one-fifth, or 20 per cent, v/as digested ; while 

 good lucerne hay with 19.3 per cent, of nitrogenous 



