114 Feeds and Feeding. 



Several devices and expedients have been offered to shorten the 

 work of calculating rations. Willard of the Kansas Station^ pre- 

 sents a system based on alligation, while Spillman of the Washing- 

 ton Station- and Jeffers'' have invented ingenious mechanical com- 

 puters. It seems best in this work to show how to perform the 

 calculations in the simplest and most direct manner. Thru such 

 drill the student will become familiar with the quantity and pro- 

 portion of the several nutrients in common feeding stuffs and the 

 amount of these required by farm animals according to the stand- 

 ards. The whole matter is less difficult and no more fatiguing than 

 the simpler arithmetical operations of the secondary schools, while 

 the benefits should richly compensate the agricultural student for 

 the time and effort. 



It should be borne in mind that both the table of digestible nutri- 

 ents and the feeding standards are but averages and approximations — 

 something far dift'erent from the multiplication table or a table 

 of logarithms. Those who will regard them as reasonable approxi- 

 mations to great vital facts and principles in the nurture of farm 

 animals will be guided and helped by what they teach. 



137. Practical considerations.— It is evident that the balanced 

 ration is only a theoretical possibility and can only be approximated 

 in practice. Indeed, in practice it is often best to feed rations 

 which are not balanced according to the standards, tho it is rarely 

 wise to depart far from them. It has been shown that crude pro- 

 tein in excess of the actual amount of that nutrient required may 

 take the place of the carbohydrates in part (75) and that the carbo- 

 hydrates and fats may in some measure replace each other. (79) Un- 

 balanced rations are often the most economical financially; for ex- 

 ample, alfalfa is relatively rich in crude protein, while corn and 

 corn forage are rich in carbohydrates but low in crude protein. 

 Where alfalfa is abundantly grown it usually sells for a low price, 

 and there is advantage in giving rations rich beyond the standard 

 in crude protein. The allowance of crude protein given in the 

 Wolff-Lehmann feeding standards materially exceeds the possible 

 minimum. In the great corn districts of the Mississippi Valley, 

 where protein-rich feeds are in relatively low supply, the feeder 

 will naturally formulate a ration made up largely of the corn plant, 

 and such rations will usually run low in crude protein, with an ex- 



» Bui. 115 ; Cyclopedia of Am. Agr., Bailey, Vol. Ill, p. 103. 



» Bui. 48. 



" H. W. Jeffers, Plainsboro, N. J. 



