50 PRINCIPLES OF FEEDING FARM ANIMALS 



they produced fell considerably short of what the same amounts of 

 digestible components contained therein would have produced, if 

 fed separately. 



In the case of these feeds the work of mastication and digestion 

 reduced their nutritive effect, and they were given lower valuation 

 numbers as a result. The following method of comparison of the 

 production values of feeding stuffs was accordingly adopted by 

 Kellner. The starch values were determined on a basis of the 

 amount of fat produced by the different digestible components, viz. : 



1 part digestible protein, 0.94 starch value. 



1 part digestible fat from oil-bearing seeds and oil meals, 2.41 



starch value. 



from cereals and their by-products, 2.12 starch value, 

 from hay and straw, roots and their by-products, 1.91 starch 



value. 

 1 part digestible carbohydrates and fiber, 1.0 starch value. 



If the nutrients of the particular feed can be regarded as of full 

 value, it is only necessary to add starch values of the three groups 

 of nutrients as shown above, which gives the total starch values of 

 the feed. If they were given lower values, the total valuation ob- 

 tained according to the preceding equivalent figures is reduced 

 by the respective valuation values. 4 The starch values thus obtained 

 have been calculated for all kinds of European feeding stuffs, and 

 are published in standard German reference books. The starch or 

 " production values " for American feeding stuffs which have been 

 published by Armsby are given in the Appendix. 



Kellner also formulated feeding standards for the various classes 

 of farm animals, which give the amounts of dry matter, digestible 

 true protein, and starch equivalents required for maintenance and 

 production in each case. These follow rather closely the Wolff- 

 Lehmann standards, except for the introduction of the starch 

 equivalents. 



Critique of the Starch Values. The Kellner starch values 

 and standards are the latest contributions to our knowledge of the 

 relative values of feeding stuffs and the feed requirements of farm 

 animals. They have been accepted by some European writers and 

 students of animal nutrition, while others, and good authorities 

 among them, consider that we are not, at the present stage of our 

 knowledge, warranted in applying the data obtained to other 



4 The valuation figures for the various feeding stuffs are given in 

 Kellner's two books, " Ernahrung d. Landw. Nutztiere " and " Fiitterungs- 

 lehre," and in the English translation of the latter book, "The Scientific 

 Feeding of Animals" (London, 1909). 



