94 FEEDS AND FEEDING 



The table shows that the pigs fed rations rich in crude protein and ash 

 made greater gains than those fed rations poor in these constituents. As 

 a rule the pigs getting the rations rich in crude protein had a larger 

 amount of blood and heavier livers and other organs per 100 Ibs. of 

 carcass. 



The strength of the thigh bones was determined in the following man- 

 ner : The two rounded, iron supporting edges of a machine used for test- 

 ing the breaking strength of materials were set four inches apart. On 

 these a thigh bone was placed, the rounded edge of the breaking-bar press- 

 ing down on the bone from above, midway of its length. The downward 

 pressure was gradually increased, being measured by the tilting beam of 

 the machine. Under the steadily increasing pressure the bone finally 

 broke, its resistance at the time of breaking being recorded. The trials 

 showed that the pigs fed the ration rich in crude protein had the strongest 

 bones. In the first Wisconsin trial, as the table shows, the bones of the 

 corn-fed pigs broke at an average pressure of 380 Ibs. for each 100 Ibs. 

 of carcass, while those of the pigs fed milk, dried blood, and middlings 

 broke at about 500 Ibs. a difference of 32 per ct. in favor of the pigs 

 getting the ration rich in crude protein. 



In the first Wisconsin trial the pigs getting milk, wheat middlings, 

 and dried blood had over 54 oz., or nearly 3.5 Ibs., of blood for each 100 

 Ibs. of dressed carcass, while those getting only corn meal had less than 

 42 oz., or but little over 2.5 Ibs. The livers and kidneys of the pigs fed 

 the rations rich in crude protein were in all cases relatively heavier, as 

 were also the tenderloin muscles, lying along the back, showing that a 

 superior muscular development was associated with the larger internal 

 organs, more blood, etc. On the other hand, the carcasses of the corn- 

 fed pigs contained an unduly large proportion of fat. Analyses of the 

 organs and parts of the pigs used in the second Wisconsin trial showed 

 further that the corn-fed pigs had proportionately less dry matter in 

 their blood and kidneys and a smaller amount of dry lean-meat tissue 

 than those on the narrow ration. 



134. Cause of poor growth on corn. It has been pointed out previously 

 that corn is low both in protein and in mineral matter, especially lime, 

 considerable of which is required to develop the skeletons of young ani- 

 mals. The protein of the corn grain is also unbalanced in composition, 

 containing large amounts of some of the amino acids, or protein build- 

 ing stones, and only small amounts of some of the others which are 

 necessary for growth. (118) The question therefore arises as to what is 

 the chief deficiency of corn: (1) too small an amount of protein, (2) 

 unbalanced protein, or (3) a deficiency in lime? 



To study the effect of adding a supply of lime to a ration of corn alone, 

 the senior author 41 carried on 3 experiments in each of which one lot of 

 pigs was fed corn alone ; a second lot, corn and hard- wood ashes, which 

 are rich in lime; and a third lot, corn and bone meal. The pigs were 



tt Wis. Rpt. 1890, Bui. 25. 



