GENERAL PROBLEMS IN SWINE HUSBANDRY 



601 



for the first period includes the feed eaten by both sows and pigs up to 

 weaning time. 



This table shows the same general facts as the one on the previous 

 page. These pigs made remarkably rapid and economical gains during 

 the latter periods, considering the heavy weights to which they were 

 carried, and the further fact that they were not on pasture during the 

 trials. Such results are possible only with carefully selected animals, 

 fed well-balanced rations under expert supervision. The last column, 

 which gives the dressing percentage of the pigs slaughtered at the end 

 of each period, shows that the percentage of dressed carcass to live weight 

 increased gradually as the pigs became older and fatter. (333) 



Economy of gain of pigs at different stages of growth 



*Average for 2 experiments. 



In these trials the pigs returned a greater margin over the cost of feed 

 for each 100 Ibs. of pork produced when marketed at about 200 Ibs. live 

 weight than at weights of 300, 400, or 500 Ibs. This shows that ordinarily 

 one should raise enough pigs to dispose of the available feed by the time 

 they reach the usual market weights of 200 to 250 Ibs. If the number of 

 pigs is limited compared with the amount of feed which one desires to 

 market thru them, and if the price of pork is high compared with the 

 price of grain, then it may be most profitable to carry the pigs to heavy 

 weights. Under such conditions this would bring the largest total 

 profit, tho the profit per 100 Ibs. of pork produced would be lower. 



914. Nutrient requirements of swine. Swine are fed largely on grain, 

 and they eat relatively little roughage, except when on pasture. More- 

 over, they grow more rapidly than cattle, horses, or sheep, and produce 

 young when less mature. Due to these facts, swine suffer much more fre- 

 quently than other classes of live stock from inadequate rations. It is 

 therefore especially necessary, if maximum profits are to be secured 

 from pork production, that their nutrient requirements be clearly under- 

 stood. In no field of animal husbandry have the recent discoveries in stock 

 feeding had a more important bearing than upon practical pork pro- 

 duction. These experiments show that the nutrient requirements of 

 swine are relatively simple, when once understood, and that it is not 

 necessary to feed complicated or expensive rations in order to secure the 

 best results. 



