606 NUTRITION OF FARM ANIMALS 



on both horses and ruminants. The results of Wolff's com- 

 parisons are contained in Table 171. 



In general, the comparisons have shown a distinct superiority 

 of ruminants over horses in the digestion of roughages, especially 

 as regards those ingredients (crude fiber and nitrogen-free ex- 

 tract) whose so-called digestion is wholly or in part a fermenta- 

 tion. Even in the better grades of forage the crude fiber was 

 on the whole considerably less digestible by horses than by 

 ruminants, although three of Tangl's experiments are excep- 

 tions, while less difference appears as regards the nitrogen-free 

 extract and scarcely any as regards the crude protein. On the 

 other hand, little difference was observed in most cases in the 

 digestibility of the total organic matter and nitrogen-free extract 

 of concentrates. In the latter the digestibility of the crude 

 fiber was also relatively low but in view of its small amount and 

 the consequent uncertainty in the results little significance 

 attaches to this difference. The notably lower figures for the 

 digestibility of the ether extract by horses arise in all probability 

 from a larger excretion of ether-soluble excretory products 

 in the feces of these animals rather than from any real differ- 

 ence in digestibility. 



716. Swine compared with ruminants. Comparisons of 

 the digestibility of identical feeds by swine and by sheep have 

 been reported by Honcamp, Neumann and Milliner, 1 the feed- 

 ing stuffs being wheat, rye and the by-products of their milling. 

 Although the results upon the individual animals of the same 

 species fluctuated somewhat, as is not unusual (718), the aver- 

 age results showed no material superiority on the part of either 

 species. 



Owing to the small percentage of crude fiber contained in the 

 feeds, the results upon this ingredient are naturally quite variable 

 and of no especial significance. Aside from this, there seems to have 

 been a slight superiority on the part of the swine in the case of the 

 rye products (with the exception of the germ), while with the wheat 

 products the reverse was the case, especially with the coarser milling 

 products. The swine seem to have digested the crude protein fully 

 as well as the sheep in all the experiments. 



Fingerling, Bretsch, Losche and Arndt, 2 in experiments de- 

 signed especially to test the relative digestive powers of sheep and 



1 Landw. Vers. Stat., 81 (1913), 205. z lbid., 83 (1913), 181. 



