4 i6 SCIENCE PROGRESS 



representing the amount of energy required for the digestion 

 of the nutrient material over and above that which would have 

 been required had the nutrient been starch. The energy value 

 so deducted is supposed to be that necessary for dealing with 

 foodstuffs in which the percentage of fibre is considerable and 

 therefore the figure deducted represents the percentage of fibre 

 multiplied by a factor which varies from o"2o, to 0*58 according 

 to the character of the foodstuff. The values of feeding stuffs 

 are thus reduced to starch values or equivalents and expressed 

 in numbers that should indicate their relative value. 



The method has been accepted generally as being by far the 

 best of the chemical methods that have been proposed for 

 valuing feeding stuffs and one naturally does not elect to 

 criticise it in any hostile spirit but rather the opposite. It 

 remains, however, to be seen how far it will apply to the 

 practice of feeding. 



The first point of interest that was observed on studying the 

 results of the East of Scotland experiments from the standpoint 

 of starch equivalents was the fact that in a comparison of Bombay 

 and Egyptian cotton cakes, the former, although the poorer of 

 the two on analysis, gave consistently somewhat better results. 



Between 1903-6, the value of Bombay cotton cake was 

 very thoroughly tested in three series of experiments which 

 were conducted in East Lothian in the winter feeding of half- 

 bred (Border-Leicester x Cheviot) hoggets. In each of the 

 three seasons the trials were carried out with six lots of sheep : 

 in the first, the lots contained thirty-eight animals ; in the 

 second and third twenty-two and thirty-two respectively were 

 used. They were folded on turnip land and each lot got as 

 much food as it would consume, subject to certain limitations 

 as to the quantity of the several items composing the respective 

 rations. The feeding began in December and was continued 

 during three to four months. 



In the second season, Egypt 

 with Bombay cotton cake. The 

 of the experiment are as follows 



Total roots consumed 

 „ hay „ 



„ concentrated food consumed 

 „ live weight increase 



Increase per head per week . 



an cotton cake was compared 

 details of this particular part 



Egyptian Bombay 



cotton cake. cotton cake. 



2 55i cw *- 2 °7i cwt. 



818 lb. 558 lb. 



i,697 ,, 1,699 ,, 



760 „ 830 „ 



2325 ,, 2539 „ 



