THE WOLFF-LEHMANN STANDARD 145 



curves as shown in the cut, 17. The horizontal spaces 

 in the illustration as indicated by the numerals at the top 

 of the cut, represent weeks and months, as shown, from 

 the ages of 3 to 9 months. The vertical spaces, as repre- 

 sented by the numerals at the left, give the values of the 

 different curves in pounds of dry matter, protein, carbo- 

 hydrate and ether extract, required daily per hundred 

 pounds live weight. It will be seen from this cut that the 

 curves start at a comparatively high point and end at a 

 comparatively low point. They do not fall gradually be- 

 tween these two points, but decline rather slowly at first, 

 then more rapidly, then again more slowly toward the 

 close. The fluctuations of the curves in this standard are 

 practically in harmony with the curve which shows the 

 total amount of feed eaten by pigs when fed according 

 to the dictates of their appetites, as shown in the third 

 section of the cut on page 24. This shows that a pig 

 when young will eat a comparatively large quantity of 

 feed, and that he gradually eats less per 100 pounds live 

 weight as he gets older, and that the curve fluctuates with 

 greater rapidity at different times practically the same as 

 the curves in the Wolff-Lehmann standard as given 

 above. 



THE STANDARD AND THE PIG. 

 The manner in which this standard is used is to mix 

 the feeds of the ration according to the nutritive ratio 

 specified therein, trying at the same time to supply the 

 total amount of dry matter called for by the standard, 

 and then to feed the pigs as much of this as they will 

 readily eat. By using this system of feeding for a num- 

 ber of years, the writer has shown that when ordinary 

 feeds are used in a ration of this character and mixed ac- 

 cording to the nutritive ratio specified by the standard. 



