RELATIVE VALUES OF FEEDING STUFFS 613 



Conditions relating to the feed 



722. Quantity of feed. Current methods of computing 

 rations regard the digestibility of feeding stuffs as unaffected 

 by the amounts consumed. As regards exclusive feeding 

 with roughage, the results of a considerable number of ex- 

 periments by various investigators appear to justify this view. 

 With mixed rations of roughage and concentrates fewer ex- 

 periments have been made, but the results indicate a distinct 

 decrease in the percentage digestibility when the amount of 

 the ration is increased considerably above that required for 

 maintenance. 



Roughage. The early experiments of Henneberg and Stohmann on 

 cattle include several cases in which varying amounts of clover and 

 meadow hay were fed and in which the digestibility was substantially 

 unaffected by the quantity consumed, and the same was found to be 

 true by Wolff at Hohenheim in a number of experiments on sheep. 1 

 Later comparative experiments by the same investigator 2 on sheep 

 and horses have confirmed his earlier results, as have also those of 

 Tangl and Weiser 3 upon sheep fed alfalfa hay or alfalfa silage, while 

 Miintz and Girard 4 likewise found no distinct effect of the quantity 

 consumed upon the digestibility of alfalfa hay by the horse. In 

 three experiments by Armsby and Fries 6 on each of two steers a sub- 

 maintenance ration of timothy hay was slightly better digested than 

 a maintenance ration in five cases out of six, but the differences were 

 small, amounting to from i.o to 2.7 per cent on the dry matter. 

 Later unpublished experiments have given similar results. In earlier 

 experiments 6 by the same authors on different amounts of clover hay, 

 practically no differences were observed. . 



Mixed rations. Kellner 7 obtained the following results in four 

 periods in which varying amounts of a mixed ration consisting of 

 meadow hay, dried molasses beet pulp, rye bran and cottonseed meal 

 were fed to cattle. 



1 Compare Wolff, Die Ernahrung der landwirtschaftlichen Nutztiere, pp. 63 

 and 64. 



2 Landw. Jahrb., 1 (1872), 533; Landw. Vers. Stat., 21 (1878), 19. 



3 Landw. Vers. Stat., 74 (1911), 277 and 282. 



4 Centbl. Agr. Chem., 27 (1898), 756. 



5 U. S. Dept. of Agri., Bur. Anim. Indus., Bui. 128 (1911), p. 27. 

 6 U. S. Dept. of Agri., Bur. Anim. Indus., Bui. 74 (1905), pp. 12-13; Bui. No. 

 101 (1908), pp. 11-13. 



7 Ernahrung landw. Nutztiere, 6th Ed., p. 49. 



