38 ILLINOIS STATE DAIRYMEN'S ASSOCIATION 



fore, they must have in their feed an ample supply of all the 

 other amino acids, or growth will be checked, production 

 lowered, or even health destroyed. 



The next important thing to remember is that the pro- 

 teins of all of the cereal grains are of the same general kind 

 or composition. All of the grains are low in some of the 

 essential building stones, or amino acids, which an animal 

 needs to build its body tissues, or which a cow needs to 

 produce milk. On the other hand, milk protein contains all 

 of the amino acids in the right proportion for the use of 

 animals. 



At the University of Wisconsin our Agricultural Chem- 

 istry Department has carried on experiments which show 

 these facts plainly. They have taken young pigs and con- 

 fined them in cages so that they could analyze all the food 

 eaten by the animals, and also all the excrements. Thus, 

 they could tell just what went on within the pig. If a 

 young pig is fed corn grain as the only kind of protein, 

 it will be able to retain or use only about 23 per cent of the 

 protein in the corn grain — less than one-quarter. 



About the same result will be secured if the pig is fed 

 wheat, barley, oats, or rye. It does not make much differ- 

 ence which one of the cereal grains is fed as the only source 

 of protein. 



On the other hand, if the same pig is fed milk protein, 

 it will be able to use for growth 55 to 60 per cent of the en- 

 tire protein in the milk. In other words, it can actually turn 

 into flesh more than one-half of the protein in its feed. 



Linseed meal is an excellent feed for live stock, is it 

 not? However, surprising results are secured when linseed 

 meal is fed as the only protein — rich feed to young pigs. 

 They will be able to use only about 17 per cent of the pro- 

 tein in the linseed meal for growth, or even less than when 

 corn or other grain is fed. 



If linseed meal is mixed with corn, a trifle better re- 

 sults will be secured than with linseed meal as the only kind 

 of protein. Even with such a combination the results will 

 not be very good, however, for the pigs will be able to use 

 only about one-third of the protein in the mixture. 



