MAITITAL OP CATTLE-FEEDIN"G, 107 



Some experiments made in "Weende by E, Sclnilze and 

 M. Marcker* showed tliat this nitrogen^ in the case of 

 sheep fed exchisivelj on hay, constituted only about 4 per 

 cent, of the total nitrogen of the excrement and equalled 

 only about 2 per cent, of that of the fodder, so that it 

 could not cause a very considerable error in the determina- 

 tion of the digestibility. In the excrement of swine, which 

 generally consume easily-digestible fodder and therefore 

 excrete comparatively little solid matter in their dung, the 

 quantity of biliary products is indeed relatively greater, 

 and their nitrogen amounts, according to experiments in 

 llohenheim and in Kusehen, to one-lixth or even onc-fouiih 

 of the total nitr<.>gen of the excrement, but, owing to the 

 high digestibility of their ordinary fodder, equals only 3 to 

 6 percent, of the nitri>gen of the latter. 



These biliary and other product'^^, then, can seriously im- 

 pair the deterniination of the digestibility of the albumi- 

 noids only when the fodder is extraordinarily poor in 

 nitrogen. For example, it was observed b v GrouA'en, at the 

 Salzmiinde Experiment Station, that full-grown oxen on 

 almost ''btarvation fodder,'" amountiufic to onlv 5 to 9 lbs. 

 of rye straw, together with non nitrogenous materials, per 

 day, sometimes excreted more nitrogen in tlieir dung than 

 they received in their fodder- 

 It is therefore difficult to arrive at even tolerably accu- 

 rate results regarding the digestibility of the protein in 

 substances so poor in nitrogen as the straw of the cereals, 

 when these are fed alone ; but with even an approximately 

 sufficient fodder, the influence of the biliary pi-oduets, etc., 

 is not at all considerable and becomes less the more nitru- 

 genous the fodder, since it has been found, at least in the 



* Jour. f. Landw., 1871, p. 40» 



