EXPERIMENT STATION. 447 



admirably fitted to supplement our farm resources for stock 

 feeding ; they can serve in regard to animal growth and 

 support, in a similar way as the commercial fertilizers in 

 the growth of our farm crops, by supplementing our home 

 manurial resources. To feed an excess of food materials, as 

 roots, potatoes, etc., which contain a large proportion of 

 non-nitrogenous matter, as starch, sugar, digestible cellular 

 substance, etc., means direct waste, for they are ejected by 

 the animal, and do not even materially benefit the manure 

 heap. In case of an excessive consumption of nitrogenous 

 constituents, — as oil-cakes, brans, gluten meal, etc., — a part 

 of the expense is saved in an increased value of the manure 

 obtained, yet scarcely enough to recommend that practice 

 bej'ond merely exceptional cases. The aim, therefore, of 

 an economical stock-feeding must be to compound our 

 various fodder materials in such a manner that the largest 

 quantity of each of the three above-stated groups of fodder 

 substances, which the animal is capable of assimilating, 

 should be contained in its daily diet to meet the purpose for 

 which it is kept. 



To compound the fodder rations of our farm stock, with 

 reference to the special wants of each class of them, is an 

 essential requirement for a satisfactory performance of their 

 functions ; to supply these wants in an economical way con- 

 trols the financial success of the industry. From these and 

 similar considerations it will be apparent that the develop- 

 ment of a more rational, and thus more economical, system 

 of feeding farm live-stock requires the following kind of 

 information : — 



First. How much of each of the three essential groups 

 of food-constituents is conluinod in the fodder we feed? 



Second. How much of each of these essential food-con- 

 stituents is digestible under existing circumstances, and 

 is thus directly available to the particular animal on trial? 



Third. How much of each of the three essential food- 

 constituents does each kind of animal require to secure the 

 best results ? 



More than twenty-five years have passed by since these 

 questions have seriously engaged the attention of skilful 

 experimenters. Sufficient valuable information has been 



