THE FEEDING VALUE OF BOOTS 8 



obtained, was due only to a larger percentage of water in the 

 milk. 



The want of reliable information as to the feeding value of 

 roots was felt so much by leading farmers that they persuaded 

 N. J. Fjord, lecturer at the Eoyal Agricultural College, Copen- 

 hagen, to make some tests for the purpose of finding the value 

 of roots as compared with other feeding- stuffs. He was par- 

 ticularly fitted for the work, having already in 1883 ascertained 

 the relative values of hand- skimmed and machine- skimmed 

 milk as food for calves and pigs in order to meet the objection 

 to the use of machine-skimmed milk which had been raised from 

 several quarters, and which threatened to delay the introduction 

 of the cream separator into the dairy industry. He had shown 

 that the difference in the feeding values of the two kinds of 

 skim-milk, in itself very small, was only due to the larger 

 amount of butter-fat left in the hand-skimmed milk, and had 

 proved that it was obviously not good economy to feed butter- 

 fat to pigs when it could be extracted by means of the cream 

 separator and turned into butter. 1 



He approached the question of comparing the different 

 feeding-stuffs in a thoroughly practical common-sense manner, 

 which made the results easily intelligible to farmers and at 

 the same time gained their absolute confidence. 



His leading idea was this : If you want the animals to show 

 you what result a certain feeding-stuff has on their growth or 

 their production, you must keep them and feed them on the 

 farms, in that manner in which practical farmers are in the habit 

 of keeping, and feeding them ; you must work with groups of 

 animals ; the groups must be as nearly alike as possible in 

 respect of average age, weight, growth and production of the 

 animals, and must be sufficiently large to eliminate individual 

 differences in the animals ; you must work with groups of 

 animals carefully selected, so that when fed alike they will 

 increase or produce alike ; you must then make some change 

 in the fodder of one or more of the groups of animals while 

 keeping the fodder of one group unchanged, so that the groups 

 of animals can show whether or not they are equally well 

 nourished by the different feeding, but you must keep within 



1 N. J. Fjord, " 19 Beretning om Fors0g," K0benhavn, ] 883. 



