20 DEPARTMENT BULLETIN 1492, U. S. DEPT. OF AGRICULTURE 
The large number of hogs represented by Table 6 is worthy of 
particular notice. The difference between the numbers used in the 
two periods is explained by the fact that 24 hogs were slaughtered 
at the termination of the soy-bean grazing. 
The daily gain during the first period was rather low, although, 
in view of the large number of hogs involved, it is probably a reliable 
average figure for the feeding employed, under conditions such as 
existed. It should be pointed out, however, that there was a wide 
variation in the rate of gain, from 0.17 pounds per hog per day in one 
Beltsville experiment to 1.21 pounds in one experiment at the Missis- 
sippi station. In fact, the gains on soy beans in the Mississippi 
experiments were consistently more rapid than in the Beltsville ex- 
periments. The probability of different varieties of soy beans od 
soy beans grown on different soils possessing different feeding values 
for hogs was pointed out in Department Bulletin 1407 (4). It is 
possible that the difference in feeding results in these experiments 
may be accounted for in this way. Further work must be done 
on this question. In one of the two Beltsville experiments in which 
mineral mixture was self-fed to one of the lots, considerably more 
rapid gain was made by the lot receiving minerals; in the other 
experiment the lot without minerals gained slightly more rapidly. 
The rate of gain during the average hardening period of 52.61 
clays was very satisfactory. Likewise, the feed required to produce 
100 pounds gain during that period shows that the hogs utilized the 
feed to great advantage. Study of the figures from which Table 6 
was prepared shows that the 62 hogs which were fed minerals with 
the corn and tankage consumed 13.7 per cent less total feed (including 
minerals) per 100 pounds gain than the 36 others. 
C. CORN WITH TANKAGE FOLLOWING SOY BEANS SUPPLEMENTED WITH A 
MEDIUM RATION OF SHELLED CORN 
Results reported in Department Bulletin 1407 (4) showed the 
feed combination of soy beans, grazed or self-fed, with a medium (2 
to 2.5 per cent) 7 ration of shelled corn to have a softening effect. The 
combination had a distinct, softening influence on pigs with average 
initial weights of 70, 100, and, also, 130 pounds, in the 12 experi- 
ments reported. 
It was considered important to determine the requirements for 
hardening such soft hogs on corn with tankage, and the Mississippi 
and North Carolina stations, with the Animal Husbandry Experi- 
ment Farm, conducted the experiments furnishing the results in- 
cluded in this summary. Nine tests, involving 74 hogs with initial 
weights of 85 pounds and over, were performed during a period from 
late in 1921 to early in 1925. In four of these tests the hogs were 
fed by the Mississippi station, in one test by the North Carolina 
station, and in the others by the Beltsville station. Seven of the tests 
were continuations throughout the hardening period of experiments 
7 A 2 to 2.5 per cent ration of shelled corn is 2 to 2.5 pounds of that feed per day for 
each 100 pounds live weight of hogs. In these investigations recalculation of tlie quantity 
of supplementary shelled corn was made on each weighing day of the hogs. In no case 
did the period elapsing between weighing days exceed two weeks. 
