CHEMICAL COMPOSITION OF MAIZE GRAIN 645 



rations so well balanced that the most complete develop- chap. 

 ment and the greatest amount of vital energy are secured at XIIL 

 the lowest cost ; or, in the case of animals for special uses, 

 providing such rations as will bring about the particular re- 

 sults desired. In other words, the feeder must know, either 

 by practical experience, or by scientific knowledge — and better 

 by a combination of both — what particular combinations of 

 foodstuffs will produce the desired results. A comprehension 

 of foods and feeding is of value no less to the manager of the 

 Mine Compound, feeding his thousands of natives with a view 

 to producing the maximum of efficiency, than to the producer 

 of beef, mutton, wool, and horse-flesh. 



To acquire knowledge of all these points by practical ex- 

 perience alone, unaided by scientific study, is at best a very 

 expensive and slow process, if indeed it is possible. The 

 practical stock feeder, without any scientific knowledge, may 

 be very successful with his stock up to a certain point, and as 

 long as economic conditions and the state of his crops and of 

 his veld remain the same ; but when any of these change he 

 finds himself in difficulty, and does not usually readjust himself 

 without loss of time and money ; often he fails financially 

 through his inability to effect an adjustment. 



But with a fair knowledge of the composition and nutritive 

 value of the different available foodstuffs he is in a position to 

 calculate what combination of materials producible on his farm, 

 or readily and cheaply obtainable, can be most effectively and 

 economically used at any time, under varying conditions of 

 season, market, and other factors which affect prices and 

 relative values. 



On the other hand, scientific knowledge is not likely to help 

 a man much unless he can combine it with sound business 

 management and practical understanding of the feeding of 

 animals. 



598. The Important Chemical Constituents of Foodstuffs. — 

 The important chemical constituents of foodstuffs in general 

 are as follows : — 



Protein (i.e. nitrogen x G'25) — muscle-forming material. 



Nitrogen-free extract (or carbohydrates minus the crude fibre) — 'fat forming 



material. 

 Ether extract, or fats, waxes, oils, and resins — heat producers. 



