SECTION IV.— FEEDING STUFFS 



CHAPTER XV 



Composition of Feeding Stuffs 



The feeding stuffs used for stock vary considerably in composition 

 and are usually very diverse mixtures. They almost invariably 

 contain thirty to forty different substances, many of them, of 

 course, in small amount only. Some of these components are of 

 the highest importance in animal nutrition ; many (and, of these, 

 generally the substances occurring in smallest quantity) have no 

 feeding value, as far as' our present knowledge goes. 



The components of the feeding stuffs, whether of animal or 

 vegetable origin, are consequently classified according to their 

 particular nutritive values, which frequently coincide with their 

 chemical grouping. Section I. has dealt fully with the general 

 composition of the plant and its products ; it will be sufficient 

 therefore to indicate forthwith the determinations which are made 

 in the chemical examination of a food-stuff. They are : — 



(1) Water. 



(2) Protein or albuminoids. 



(3) Non-protein nitrogenous substances. 



(4) Fat or oil. (Ether extract.) 



(5) Carbohydrates or nitrogen-free extract. 



(6) Crude fibre. 



(7) Ash and sand. 



According to the particular type of food-stuff being examined, 

 these determinations may be modified or some of them left out. 

 In special cases also, particular estimations are included, as, for 

 example, in the estimation of the gluten of wheat or the sugar in 

 roots. 



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