354 AGRICULTURAL CHEMISTRY 



ing pigs, a mixture of shorts and corn or shorts and 

 barley with skim milk will be found preferable to any 

 single grain. Skim milk should not be used in greater 

 amounts than 3 pounds for each pound of grain. Five 

 pounds of skim milk will produce as much gain in weight 

 as one pound of grain. For fattening pigs the grain mix- 

 ture should contain more corn than shorts. Coarse 

 ground barley is a valuable food and produces a good 

 quality of pork. Peas may form about one-third of 

 the grain mixture. For fattening purposes, foods with 

 a large amount of digestible protein are not as essential 

 as for growing animals because the excess of protein is 

 used for the production of fat which can be produced 

 from less expensive nutrients as carbohydrates. The 

 food should not be too concentrated in character. Many 

 of the grains are so highly digestible that there is present 

 in the digestive tract only a limited amount of insoluble 

 matter to dilute the waste products. This is particularly 

 true of peas and corn. Charcoal and a small amount of 

 corn- and cob- meal are found useful to correct such de- 

 ficiencies. A small amount of some forage crop as chopped, 

 steamed or soaked clover should be at the disposal of the 

 animal. Wheat, barley and rye, if fed, should be coarsely 

 ground, but in the case of corn, grinding is not so essen- 

 tial. Bone-meal, dried blood, and meat scrap are valuable 

 in a ration for pigs, particularly if corn is the principal 

 grain used. Among the forage crops, rape, clover, alfalfa, 

 sorghum and corn will be found most valuable for pork 

 production. 



479. Food Requirements of Sheep. In the case of 



