470 



MAKtTAl OF CATTLE-FEEDmO- 



Water. 



Protein 



Fafc 



Nitrogen-free extract — 



Crude fibre 



Ash ,7 



Hay. 

 Pur cent. 



Oat straw. 

 Per cent. 



Mangolds. 

 Per cent. 



BicwcTrt' 



p^mins. 



Per cent. 



u 



14 



88 



9 



4 



1 



2 



1 



. . 



43 



33 



9 



S6 



44 



1 







4 



1 



100 



100 



100 



11 



loa 



We liave now to estimate tlie percentage of eaeli of 

 the ingredients of these feeding-s tufts whicli is digestible. 

 Tlie mangolds, like all roots and tubers, we may assume 

 to be wholly digestible- For concentrated fodders we may 

 in most cases assume the average digestion coefficients, 

 both because the digestibility of these fodders varies less 

 than that of coarse fodder, and because fewer experiments 

 have been made on them. On brewers' grains there have 

 been no experiments, but our table gives estimates of their 

 digestibility, and these we accept provisionally in the absence 

 of anything more exact. 



Of the non-nitrogenous ingredients of the coarse fodder, 

 the fat is present in so small quantity that the assumption 

 of average digestibility can introduce no serious error, 

 while, as we have seen (p. 250), the nitrogen-free extract 

 of a coarse fodder represents a])proximately the total quan- 

 tity of digestible carbhydrates which it contains. This 

 fact, thongli only true in a general way, probably forms as 

 accurate a basis for computations of dii>:estibilitv as is fur- 

 nished by the use of digestion coefficients, especially if au- 



