108 TWENTY-FIFTH ANNIVERSARY REPORT. 
On the average of twenty-six feeding trials, including all of the 
most normal as to food and season the food cost per pound gain 
in weight made by pigs during the first period after separation from. 
the sow was about half as much (51 per ct.) as that during the 
period immediately preceding removal. The difference from the 
average cost for all the time with the sow was not much less. It 
was considered that where sweet skim milk was to be used pigs 
should have the opportunity to feed in part separately from the 
mother as young as possible. The best time for separating alto- 
gether would depend upon the character of the food to be used, 
the time of year, and the special purpose for which the animals, 
young and old, were intended. 
COMPARISONS GF PIGS OF DIFFERENT BREEDS AND CROSSES.! 
During four years a number of feeding trials were made with 
different lots of pigs of five pure breeds and of seven first crosses. 
In all thirty different lots were fed, some of them for only about 
three months when young, but most of them for from seven to nine 
months. Weekly records were kept and most of them published 
_ in reports of the station averaged by periods of from three to five 
weeks. 
There was not very great difference on the average in the size 
reached at any medium stage of maturity, except that pigs of the 
Small Yorkshire breed were always smaller at the same age than 
those of the other breeds tried. Pigs of the Yorkshire-Tamworth 
cross, however, were some of the largest grown, resembling the 
dam in type, as did also the reverse cross of these breeds, the Tam- 
worth—Yorkshire, which gave smaller pigs. All pigs of both these 
crosses were white. The pigs of Yorkshire-Tamworth also were in 
some respects the most satisfactory of any fed. Some of the largest - 
grown were of the Tamworth—Poland China cross. In average size 
of pigs when farrowed there were in order: Berkshire, Poland 
China—Duroc cross, Poland China, Tamworth—P. China cross, 
Yorkshire-Tamworth cross, Tamworth—Yorkshire cross, Duroc, 
O. I. Chester-P. China cross, Tamworth, Tamworth—Duroc cross, 
Berkshire—Cheshire cross and the Yorkshire, the average weight for 
the latter breed being 2 pounds and for the Berkshire 3.4 pounds. 
Of three lots fed at one time the Poland China pigs made con- 
siderably the more profitable growth, the Duroc next and the Berk- 
* Rpts. 11: 286-290 (1892); 12: 224-234 (1803); 14: 475-493 (1895); 15: 
658-665 (1806). 
