Nutrition Studies. 67 



In forming rations the lime and phosphorus content of the 

 feeds should be considered. Straw, chaff, the various root crops, 

 molasses, and the cereals and their by-products, such as bran and 

 middlings, are all low in lime. On the other hand, the legumes, 

 as clover, alfalfa, etc., the meadow grasses, and many leguminous 

 seeds, such as peas, beans, etc., are high in lime. Straw, chaff, 

 beet pulp, potatoes, and molasses are low in phosphorus, while 

 the cereals and brans, malt sprouts, oil cakes, brewers' grains, 

 and slaughter-house and fish waste carry it in abundance. In 

 many cases where soft water is drunk, there may be a lack of lime 

 only, in others both lime and phosphorus may be deficient. 



90. Inorganic phosphorus. Kohler 1 found that lambs can assim- 

 ilate and use calcium phosphate, bone ash, and steamed bone. 

 J. Neumann 2 fed calcium carbonate and calcium phosphate to calves 

 with good results. Experiments at Mockern 3 indicate beneficial 

 results from the use of 30 to 50 grams of calcium phosphate in 

 the daily ration of steers which had shown marked brittleness of 

 bone. At the Wisconsin Station, 4 Hart, McCollum, and Fuller 

 found that pigs were able to assimilate inorganic phosphorus sup- 

 plied in the form of precipitated calcium phosphate, bone ash, or 

 ground rock phosphate. (122) 



Other experiments are somewhat contradictory in results, but 

 on the whole it appears well established that mineral matter in 

 inorganic form may be absorbed from the digestive tract of farm 

 animals. Animals suffering from lack of lime and phosphorus 

 absorb calcium phosphate with beneficial . results, and even with 

 normal rations the addition of calcium phosphate causes increased 

 bone formation. Hence when a ration must be used which is de- 

 ficient in either lime or phosphorus, or both, lime may be sup- 

 plied in the form of calcium carbonate in wood ashes or ground 

 limestone, or phosphorus and lime in the form of precipitated 

 calcium phosphate, bone ash, or ground rock phosphate. This 

 latter is by far the cheapest form of phosphorus easily available 

 for such purposes. 



91. Common salt. The hunger of herbivorous animals for com- 

 mon salt is well known, but practical men have differed as to the 

 necessity or advantage of adding it to the ration. In spite of the 

 earlier belief that salt increased the digestibility of food, numer- 

 ous experiments have shown that the digestibility of the ration 



1 Landw. Vers. Stat., 61, 1905 ; 65, 1907. 8 Landw. Vers. Stat., 57, 1902, p. 239. 



2 Jour. Land., 41, 1893, p. 343. * Eeseareh Bui. 1. 



