CONVERSION OF FEEDING STUFFS 33 



If the losses occurring in the process of conversion are included in the 

 calculation, the starch values with reference to the original material are 

 as follows : 



Per cent 



Straw 13.4 



Straw pulp of paper mills 42.0 



High-grade converted straw 39 to 42 



Moderately converted straw 38 to 40 



Whether the conversion of straw as practiced by present methods will 

 continue to be practiced after the return to normal conditions remains to 

 be seen. The Lehmann and Colsmann methods are undoubtedly too ex- 

 pensive (necessary apparatus, etc.). Beckmann's method may survive, 

 but much will depend upon the condition of the grain and feed market. 

 From a national economic point of view it would undoubtedly be a bless- 

 ing if the enormous straw product of the country could be more profitably 

 utilized than in the past. 



Animals must be accustomed gradually to the use of wet "straw con- 

 centrate." At first three to five pounds are given daily, divided into three 

 feeds and mixed with other material. If oats are added they should first 

 be crushed. 



Pea, rape and turnip straw have thus far proved rather refractory to 

 the conversion processes. 



The conversion of wood meal, or sawdust, by treatment with hydro- 

 chloric acid or with sodium or sulphite lye has not as yet given encourag- 

 ing results. The digestibility and palatability depend upon the species of 

 the wood as well as upon the part of the plant or tree furnishing the same 

 (base or trunk, branches, etc.), whether the sawdust is the product of 

 cross-cut or longitudinal sawing, the method of conversion employed, etc. 

 The variation in this respect is quite marked. Ether-soluble constituents 

 (resins, turpentines, etc.) affect digestibility and palatability unfavorably. 

 The admissible maximum of these substances varies between 0.6 and 0.8 

 per cent. These substances are not present in sulphite and sodium cellu- 

 lose. 



Converted fir-tree sawdust or meal, highly saccharinated pine wood 

 meal and sulphite cellulose have the following composition (Ellenberger 

 and Waentig) : 



Crude Crude Nit.-free Crude 



Material Water Ash Protein Fat Extract Fiber 



Percent Percent Percent Percent Percent Percent 



Fir wood, sawdust or meal 9.3 1.7 1.12 0.8 28.6 58.4 



Pine wood, sawdust or meal ... 7.4 2.6 1.25 0.6 30.9 57 



Sulphite cellulose 8.9 1.3 ... 0.4 17.0 72!5 



The digestibility of straw pulp, according to Kellner and Fingerling, 

 is 89 per cent in cattle and swine, sheep 83 per cent, while that of high- 

 grade converted straw is 68 to 70 per cent, low-grade converted straw 

 60 to 65 per cent, surphite cellulose or wood cellulose 79 per cent, sodium 



