NUTRITIVE RATIO. 237 



Non-nitrogenous substances include, in particular, starch, 

 dextrine, cane-sugar, grape-sugar, gum, pectine, and the 

 digestible portion of the cellular matter of the fodder. 

 These substances are readily transformed, within the diges- 

 tive organs, into soluble compounds of a similar chemical 

 character, and are thus assumed to serve an identical physio- 

 logical purpose. 



The nutritive ratio of a fodder substance means the 

 numerical relation of its nitrogenous substances (1) as 

 compared with the sum of its non-nitrogenous, digestible 

 organic constituents, fat included. To the fat is frequently 

 assigned a higher numerical representation in the sum of 

 the non-nitrogenous substances than the mere analytical 

 results entitle it to. Grouven counts its nutritive value, in 

 case of grains, &c, equal to three times its amount of starch ; 

 in case of straw, equal to 2.75, and, in some other substances, 

 equal to 2.5 times. Other authorities of a later date (J. 

 Kiihn) favor the opinion that the amount of fat might be 

 less than is usually claimed to be desirable wherever a 

 liberal amount of sugar was present. In summing up my 

 analytical results to ascertain their nutritive ratio, I have, for 

 obvious reasons, assigned to fat merely the numerical value 

 of the actual quantity found present. 



The analytical chemical results of any of our fodder 

 crops are, for practical purposes, usually presented under 

 six headings : viz., — 



1. Percentage of moisture lost at 110° C. temperature. 



2. Percentage of nitrogenous matter. 



3. Percentage of non-nitrogenous matter (exclusive of 

 fat). 



4. Percentage of fat. 



5. Percentage of mineral constituents. 



6. Nutritive ratio. 



In my subsequent analytical statements I have calculated 

 the results obtained, in the case of corn and cob, for one 

 and the same state of moisture ; namely, ten per cent : the 

 analyses of other investigators are recalculated for the same 

 amount, whenever desirable to render the difference in their 

 composition at once apparent. The cellulose has been as- 

 certained by actual test in I., V., X : in the remaining sam- 

 ples the mean of those tested has been assumed. 



