GROWTH 411 



490. Fattening experiments with pigs. Of the more recent 

 experiments upon the influence of the protein supply upon the 

 rate of gain of immature fattening pigs, four series made by the 

 Halle Experiment Station at Lauchstadt 1 and a series of co- 

 operative experiments at a number of the German experiment 

 stations under Kellner's general direction are of special interest. 

 While these relate primarily to fattening, the comparative 

 results with rations of equal energy content should furnish 

 some indications as to the sufficiency of the protein supply, 

 since the rate of increase of protein tissue can hardly be sup- 

 posed to differ materially from that in simple growth without 

 fattening. 



In the Halle experiments it is interesting to note the gradual 

 lowering of the average protein supply from the high level of 

 the first series. The final series seems to show that satis- 

 factory results may be obtained from rations whose protein 

 content per 1000 pounds at the different weights of the animal 

 is as follows, although the earlier trials seem to indicate some- 

 what higher figures. 



TABLE 100. ESTIMATED PROTEIN REQUIREMENTS OF FATTENING PIGS 



At weight 77-100 Ib 4.0 Ib. 



At weight 110-165 Ib 3.0 Ib. 



At weight 165-220 Ib 2.0-2.5 Ib. 



At weight over 220 Ib 2.0 Ib. 



In 1906 cooperative experiments were initiated by the Ger- 

 man Agricultural Council at a number of German experiment 

 stations upon the value of potatoes as feed for fattening pigs 

 and especially upon the protein supply necessary for their 

 most complete utilization. The results of experiments upon 

 this point at eleven stations, upon a total of 184 animals, have 

 been discussed by Kellner 2 under whose general direction the 

 work was done. According to Kellner 3 young fattening pigs 

 should receive per 1000 live weight the following amounts 

 of protein : 



1 Landw. Jahrb., 28 (1899), 947 ; 31 (1902), 916 ; 36 (1907), 679 ; 39, Ergzbd. Ill 

 (1910), 179. 



2 Ber. Deut. Landw. Rat, Heft 3 (1908). 



3 Die Ernahrung der landw. Nutztiere, $th Ed., p. 488. 



