i8o AN AGRICULTURAL WAR PROBLEM 



ever, after a considerable search through the litera- 

 ture a fairly satisfactory table based on British 

 analyses was compiled. 



An ordinary analysis however is not a reliable 

 measure of relative feeding value, for fodders differ 

 greatly in digestibility. Thus of the total amount 

 of nutrients shown by analysis to be present in 

 linseed cake about 90 per cent, is digestible, whilst 

 in hay the digestible nutrients do not amount to 

 much more than half the total nutrients indicated 

 by an ordinary analysis. A determination of the 

 digestible nutrients in a sample of a feeding stuff 

 is a lengthy and not very pleasant process, in- 

 volving the collection and analysis of the whole of 

 the solid excreta of an animal for a period of about 

 10 days, whilst he eats a known weight of the 

 food. Information is fortunately on record as to 

 the digestibility of almost every known feeding 

 stuff. For instance it is known that of the protein 

 of linseed cake 86 per cent, is digestible, of the fat 

 90 per cent., of the carbohydrates 80 per cent, and 

 of the fibre 50 per cent. Similar figures are avail- 

 able for almost every kind of feeding stuff. From 

 these figures and the table of the average composi- 

 tion of the feeding stuffs on the home markets it 

 was possible to calculate Table I which shows the 

 percentages of digestible nutrients in all the feed- 

 ing stuffs included in the quotations collected by 

 the Board of Agriculture. 



It will at once occur to anyone acquainted 



