MA]jq"UAL or CAITLE-FEEDIXG. 1(15 



and analyzed in exactly the same way. Tlie ab.<ohite i|iian- 

 tity of each nutrient wliieli enters and lea\es the IhkIj be- 

 ing thus known, the difterenee between the total amount 

 of dry matter in fodder and dmig gives the total amonnt 

 of matter digested, and the difference in the amoont of 

 any particular constituent, e, g,^ crude liber, shows how 

 much of tliat constituent has been diiretoted. 



It is a matter of course that the greatest care nuist be 

 exercised, both in the weighing off and portioning lait of 

 the fodder, in the collection of the excrement, and in the 

 preparation of a correct sample for chemical analvhis. 



In fact, a high degree of accuracy has been reached in 

 such " digestion experiments " by the help of various ap- 

 paratus, stall fittings, and other arrangements, as may be 

 seen from the results of control experiments, especially 

 when the animal is of a kind favorable to the attainment 

 of accurate results. The latter is generally the case with 

 the smaller animals, particularly with sheep. 



The Time occupied in Digestion in the niminants is 

 comparatively long ; it has been found by nmnerous obser- 

 vations, made in various w^ays with the same result, that 

 after a sudden alteration of the feeding, the remnants of 

 the former fodder are still recomizable in the excrements 

 for as much as five days. Accordingly, in all digestion 

 experiments, the fodder whose digestibility is to be deter- 

 mined must be fed for a period of several days before the 

 excrement can be safely considered as corresponding to the 

 fodder and before a sample can be taken for analysis. 

 This preparatory period must, of course, be long enough to 

 insure the complete elimination of the remnants of the 

 previous fodder ; generally it is extended to at least seven 

 days. 



This preparatory period ib the more important bince the 



