474 EXPERIMENT STATION RECORD. [Vol. 38 



tlioroufchly worker! out. These experiments were carried on to determine the 

 optimum amounts of tankage, soy bean meal, linseed meal, and .skim milk with 

 corn in pork production. 



In the first experiment three lots of five pigs each were fed for 16 weeks just 

 after weaning on coarsely ground corn and tankage. In lot 1 the tankage was 

 fed in a definite proportion with the corn, in lot 2 in a constant daily amount, 

 and in lot 3 in a decreasing percentage, beginning with 20 per cent the first 

 week and decreasing 1 per cent weekly to 5 per cent at the close. The results, 

 while not differing greatly, were in favor of the first and third lots. 



In a second trial with throe lots of four pigs each, averaging 57.5 lbs., lasting 

 16 weeks, the pigs fed tankage in decreasing amounts each week made larger 

 gains and required less feed per unit of gain than those fed the tankage in a 

 definite proportion with the corn or those on a constant daily allowance. 



In a third trial two lots of four pigs each, averaging 75 lbs., were fed for 16 

 weeks. Lot 1 was fed corn and tankage, 8 : 1, and lot 2 corn with tankage de- 

 creasing from 20 to 5 per cent. The results were the reverse of those in the 

 two preceding trials, the feeding of definite amounts of tankage giving greater 

 increases in weight at a lower expenditure of feed. 



In a fourth experiment 30 pigs averaging 47 lbs. were divided into six lots 

 and fed narrow, medium, and wide rations of tankage with corn, the supplement 

 being fed in constant proportions and in decreasing amounts. With large 

 amounts of tankage the best results were obtained in feeding it in a definite 

 proportion to corn. With small amounts of tankage best results were shown 

 when it was fed in larger amounts at first, gradually decreasing the proportions. 

 The medium rations gave better returns than the wide or narrow. 



The fifth experiment was made to compare tankage, soy beans, and linseed 

 meal as supplements to corn (the first two in varying amounts) in feeding hogs. 

 Eight lots of five pigs each, averaging 144.9 lbs., were employed. Those fed 10 

 per cent of tankage in the ration made a 36.2 per cent average increase in rate 

 of gain and required 10.4 per cent less feed than the lot on corn alone. Better 

 returns were given with 10 per cent of tankage in the ration than with 20 per 

 cent or with 5 per cent. As the supplemental feed increased in the ration more 

 of it was required to replace a unit of corn. On a basis of equal amounts of 

 protein soy bean meal and linseed meal gave a higher result than tankage, ow- 

 ing to their nonnitrogenous contents. Tankage was most consistent in producing 

 economical gains. In the beginning of the experiment soy bean meal gave gains 

 with less feed, but in the latter part of the experiment it was surpassed by 

 linseed meal. 



In the sixth experiment a lot of six pigs averaging 71.75 lbs. was fed corn 

 and tankage in a self-feeder for 14 weeks, being allowed to select either feed as 

 wanted. They made an average daily gain of 1.5 lbs. per head with the use 

 of 3.89 lbs. of feed per pound of gain. The amount of tankage consumed in- 

 creased during the first three weeks from 14.6 to 19 per cent of the ration and 

 then decreased to about 5.6 per cent for the last eight weeks of the test. The 

 average consumed during the experiment was 12.4 parts of corn to 1 part of 

 tankage. 



In the seventh exiieriment three trials were made of skim milk as a sup- 

 plementary feed with corn for pigs in dry lot. Where fed ad libitum the 

 pigs consumed less milk as they became older. As the milk was increased in 

 the ration its replacement value with corn was decreased. Compared with 

 tankage as a supplement to corn it was less costly per pound of gain, though 

 there was less difference during the second half of the test than there was 

 during the first half. 



