403 MAKUAL OF CATTLE-FEEDIKG. 



lliougli Ic&s simple tliaii merely taking tlie average per- 

 centages of (ligestil)le ingredients from a table, ib likely to 

 give results correbpondiug more closely to tlie ti'uth, when 

 intelligently carried out, and lias also the advantage of 

 keeping prominently before the mnid the approximate 

 character of the calculation. 



Two facts will serve to aid us in forming a judgment as 

 to the amounts of digestible nutrients which a given fodder 

 will furnish: first, thjg, digestibility of a feeding-stuff de- 

 pends largely on its chemical composition, and second, the 

 composition of coarse fodder is quite variable, while that 

 of the concentrated fodders is more constant. 



Our first step, then, in the case supposed, is to form an 

 esthuate of the composition of the hay, straw, and roots 

 w^hich are to form the basis of the ration. By far the most 

 satisfactory method of dohig this is by the help of a partial 

 analysis, and such analybcs of feeding-stuffs might appro- 

 priately be undertaken by the Experiment Stations now 

 beginning to be established in our midst. In the case of 

 a coarse fodder, like hay or straw, determinations of water, 

 protein, and crude fibre should be made; in concentrated 

 fodders water and protein, and in some cases fat, should be 

 determined. For the ash and fat of coarse fodders and the 

 ash and crude fibre of concentrated fodders the average 

 numbers may safely be taken, while subtracting the sum 

 of the protein, crude fibre, fat, and ash from 100 will give 

 the approximate amount of nitrogen-free extract. In this 

 way the composition of the feeding-stuffs in question may 

 be determined with sufficient aecnracy for the pu^ose. 



"When it is not practicable to procure an analysis of the 

 feeding-stuffs to be used, their composition must be esti- 

 mated as well as may be by the aid of the table in the Ap- 

 pendix. This table shows the extremes of composition 



