CALCULATION OF RATIONS 73 



The ration as given might be improved by feeding a concentrate, 

 like cottonseed meal, in the place of linseed meal. This feed con- 

 tains still more digestible protein than the linseed meal, viz., 37.6 

 per cent and, by substituting 2 pounds of it for the linseed meal, 

 the digestible protein of the ration would nearly meet the require- 

 ments of the standard. It would make a less palatable ration for 

 cows, however, and in some parts of the country would render it 

 somewhat more expensive. 



Another change in the ration that would bring it closer to the 

 standard in digestible protein and nutritive ratio would be to replace 

 one-half of the wheat bran by middlings, or one-half of the corn meal 

 by oats or barley. The desirability of making these changes would 

 depend mainly on the cost of the various feeds. The nutritive effect 

 of the ration would not be likely to be materially influenced by the 

 changes suggested, except that it is, in general, advisable to feed a 

 mixture of ^several feeds to dairy cows and heavy-producing animals 

 rather than only one or two, as it will increase the palatability of 

 the ration and stimulate the appetite. The preceding ration is, how- 

 ever, satisfactory as given and will produce good results "at the pail." 



Nutritive Ratio. We notice that the nutritive ratio of the ration 

 given is 1 : 6.5 instead of 1 : 5.6, as required by the standard. It 

 follows from what has been said, however, that it is not important 

 to bring the nutritive ratio closer than this to the standard. 



Up to recent times a definite nutritive ratio was considered 

 important for the specific purpose of feeding in view; e.g., 1 : 5.4 was 

 the required ratio for milch cows, according to the original Wolff 

 (German) standard, and it was not deemed advisable to vary greatly 

 from this ratio. Investigations conducted since the publication of the 

 Wolff-Lehmann standard have shown, however, that, given a certain 

 minimum of digestible protein in a ration, its exact nutritive ratio is 

 of no great importance ; but a liberal supply of total digestible matter 

 in a ration is important, and a nutritive ratio of 1 : 7, or even wider, 

 may prove nearly as efficient for feeding dairy cows as a narrow 

 ration, provided the former ration furnishes a more abundant supply 

 of digestible nutrients. This applies with special force to fattening 

 animals, 1 but holds good also in the case of dairy cows and ether 

 animals to which it was formerly considered necessary to supply 

 rations of especially narrow nutritive ratios in order to secure a 

 large and economical production. 



1 See Kellner, Landw. Versuchs-Stationen, vol. 53, pp. 1-474. 



