PRINCIPLES THAT GOVERN FEEDING 177 



TABLE I Continued 



- 



Field roots 1 | ||g| 2 



and tubers . g fi| J|g g 



Ss *i :| III* 



la Si s 505* g 3 



H fc fc U 0-31 



Sugar beet pulp ..... 10.1 1.0 0.2 6.3 2.2 0.4 



82 63 84 83 



Mangels ............... 8.8 1.4 0.2 5.4 0.8 1.0 



79 75 91 43 



Sugar beets .......... 13.3 1.5 0.1 9.9 0.9 0.8 



95 91 50 100 100 



Rutabagas .......... 11.4 1.2 0.2 7.5 1.3 1.2 



87 80 84 95 74 



Turnips .............. 9.4 1.3 0.2 5.9 1.2 0.8 



93 90 98 97 100 



Potatoes .............. 21.3 2.1 0.1 17.3 0.6 LO 



77 44 91 



Nutritive ratio. By the term nutritive ratio is meant 

 a statement of the proportion of the digestible nitrogenous 

 substance in a feeding ration to the digestible proportion of 

 the non-nitrogenous substance. It is obtained by dividing 

 the total digestible non-nitrogenous substance in the same 

 by the total digestible nitrogenous substance. The total di- 

 gestible nitrogenous substance is simply the digestible pro- 

 tein. The total digestible non-nitrogenous substance is the 

 sum of the digestible carbohydrates other than fibre, of the 

 digestible crude fibre, and of 2% times the digestible fat. 

 The digestible fat is multiplied by 2^4 to place it on the 

 same basis as the carbohydrates in heat production. It 

 has been found that although the carbohydrates and fat are 

 about equal for producing flesh, if one pound of digestible 

 fat is burned under water, all the heat being conserved, it 

 will raise it to the same temperature as would 2% pounds 

 of digestible carbohydrates burned under similar conditions. 

 Therefore, the power to produce heat is 2j4 times greater in 

 the former than in the latter, and this is true of these food 

 factors in the production of heat in the animal body. 



It will be apparent, therefore, that with a table of feed- 

 ing stuffs at hand giving the relative amounts of the or- 

 ganic substances in any food stuffs that are digestible, the 



