110 THE CHEMISTRY OP THE FARM. 



richer in fatty matter it would occupy a higher place in 

 the table. 



We should conclude from these calculations that an 

 equal weight of dry food, as maize, peas, or oil -cake will 

 have a nearly similar feeding value if supplied to an 

 animal receiving a sufficient amount of albuminoids in its 

 diet, as, for example, if given to a sheep fed on good 

 meadow or clover hay. 



Many foods may, in fact, be substituted for each 

 other without injury to the nutritive value of the whole 

 diet. A farmer should thus be able to introduce economy 

 into his feeding by watching the market, and making use 

 of those foods which are cheapest. In making his 

 selection, the manure value of the food must, however, 

 be taken into account. 



2. Proportion of Albuminoids to Non- Albuminoids. 

 A point of considerable importance in determining the 

 suitability of a food as an article of diet is the proportion 

 between the digestible albuminoid and the digestible 

 non-albuminoid organic constituents: this relation is 

 most conveniently termed the ' ' albuminoid ratio " of the 

 food. Before calculating this relation, the non-albuminoid 

 ingredients of the food are first reduced to their equiva- 

 lent in starch.* Taking the average composition of 

 foods already given, and the digestibility of their con- 

 stituents shown by the German experiments, the albu- 

 minoid ratios will be as follows : 



* It has been usual to multiply the fat by 2 '5 to obtain its equivalent in starch 

 and to add the product to the digested carbo-hydrates and fibre to obtain the total 

 non-albuminoid nutritive matter. In the following table the fat has been multi- 

 plied by 2'3, and the carbo-hydrates (and in the second column the amides) re- 

 duced to their approximate equivalent in starch, according to the relations shown 

 on p. 108. 



