240 



LIVESTOCK ON THE FARM 



The curve for protein above starts at 0.6 pound at the be- 

 ginning of the experiment and rises to 0.7 during the first 

 seven weeks. Following this' it dechnes to 0.6 during four 

 weeks; then maintains a level of 0.65 for seven weeks. After 

 this the greater part of the nitrogenous feeds are removed 

 from the ration during four weeks. A little of some protein 

 feed, however, is fed to the close as pigs will do better if they 

 have more protein than is found in corn. 



The form that this curve takes, however, should not be 

 taken as absolute but should be modified to suit the length of 

 the feeding period. The writer feeds pigs for six months, from 



Fig. 62. — Protein requirement of market pigs. 



three to eight months of age inclusive, according to this for- 

 mula. Thus the pig is eight months old at the close of the feed- 

 ing period. The last eight weeks is considered as the fattening 

 period and the first eighteen weeks the growing period. This 

 growing period is divided in the middle by a period of four 

 weeks during which the protein curve drops for the purpose 

 of reducing the factor of waste. With a short growing period 

 a continuous increase during the period would be all right but 

 when a comparatively large quantity of protein is fed for a 

 considerable length of time under practical conditions the fac- 

 tor of waste apparently becomes so great that feeding becomes 

 relatively more unprofitable. 



For Breeding Pigs. — In order to develop pigs to the best 

 advantage for breeding purposes the following guide should be 

 used. 



The same comments apply to this curve as to the one pre- 

 ceding. The difference as will be seen is that pigs being devel- 

 oped for breeding purposes should have less protein than those 

 that are fed for market. 



The amount given as best for the development of market 

 pigs to produce the largest and most economical gains up to 



