PART III. FEEDING STUFFS 

 CHAPTER XIII 



VALUATION OF FEEDING STUFFS 



Constituents of Feeding Stuffs. All estimates of the value 

 of feeding stuffs, whether for agricultural or commercial pur- 

 poses, i.e. the nutritive or the pecuniary values, are based 

 ultimately on the composition as determined by chemical 

 analysis. Even when the object is to determine the thermic 

 or dynamic value of a substance, it is generally easier to do 

 this by calculation from the composition than by direct 

 estimation. 



The results of chemical analyses of feeding stuffs are 

 generally expressed in percentages as follows : 



(1) Albuminoids (or crude protein). 



(2) Crude fat (or ether extract). 



(3) Soluble carbohydrates (or nitrogen free extract). 



(4) Crude or woody fibre. 



(5) Moisture. 



(6) Ash (or mineral matter). 



The figures for albuminoids or crude protein are obtained 

 by simply multiplying the percentage of nitrogen by the factor 

 6*25 (cf. p. 67). It includes any amides or other nitrogenous 

 compounds which may be present ; and for this reason, some 

 writers prefer to call it the total nitrogenous matter. The 

 seeds of plants, e.g. cereal grains, oil cakes, etc., contain little 

 if any amides. Practically the whole of the nitrogenous matter 

 in these products is true protein. The vegetative organs, 

 especially roots, e.g. turnips, contain varying amounts of 



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