MOISTENING AND SOAKING 29 



The grains are frequently ground, cracked or "rolled" so that the con- 

 tained nutrients may be the better utilized in the various digestive pro- 

 cesses. "Rolling" breaks the skin or shell of the grain but the crushed 

 contents remain intact. "Cracking" serves to reduce the grain to smaller 

 but coarse particles. Grinding reduces it to a powder form. 



These processes all serve to increase digestibility to some extent, about 

 1 to 2 per cent for oats fed to healthy horses, and 5 to 10 per cent for 

 swine. In case of the hard grains (corn, rye, beans and peas) the advan- 

 tages are still more marked (Jordan and Hall, Gay, Henry). For these 

 reasons the moderately soft grains are usually fed whole to horses and 

 swine, while the hard grains give better results when rolled, crushed or 

 ground and fed with cut feed. Swine should never receive whole grain 

 for most economical results. 



2. Moistening and soaking assist or facilitate prehension, prevent 

 blowing away or inhalation of finely divided or dusty particles, and facili- 

 tate mixing. According to Kuehn it has no appreciably favorable effect 

 on digestion. It is usually practiced in cattle feeding and avoided for 

 horses and sheep. In more recent times the moistening or soaking of the 

 concentrates is usually dispensed with as serving no special end, except 

 in swine, when liberal additions of water are frequently made. 



For cattle and even for swine dry feeding is now being practiced more 

 and more. Dry feed is consumed more slowly, masticated more thor- 

 oughly, mixed better with the saliva, and consequently, in all probability, 

 is more thoroughly utilized by the body. 



In general, long-continued soaking has not proved of advantage. It is 

 still resorted to chiefly for hard grains that for certain reasons it may not 

 be practicable to crack or grind, and for dried pulp, etc. 



3. Cooking, scalding and steaming save energy in aiding mastication, 

 increase palatability, destroy injurious microorganisms, animal parasites 

 and chemical poisons (lupines), but they also destroy the enzymes which 

 happen to be present in the feeding stuffs so treated. The digestibility of 

 the crude protein is reduced or impaired by cooking, etc. 



In general, it is not advisable either to cook, scald or steam pure or 

 unspoiled feeding stuffs that are easily digestible in the raw state. The 

 practice is rather to be limited to feeding stuffs that would otherwise not 

 be completely utilized and to such as require the application of heat to 

 remove certain injurious properties. 



The cooking or steaming of potatoes has become quite customary and 

 there is no doubt that their digestibility and palatability are improved in 

 this way. Cooking and steaming are also resorted to for the removal of 

 the toxic substances in lupines. 



According to the method of Kellner, the lupine seeds are soaked in cold 

 or in lukewarm water for 24 to 36 hours, then boiled for one hour, or 

 steamed (without pressure) and then leached with cold water to remove 

 their bitter taste. The leaching process requires about 48 hours and may 

 be conducted with flowing water or by changing the standing water every 



