McMullen said this study was designed with several objectives in mind. We're also comparing feed efficiency, average daily gain, feed cost per pound of gain, and water consumption differences between the two groups. McMullen said approximately 50 pigs at a beginning weight of about 70 pounds are used in each of the groups. Both groups are divided into three pens, and all six pens are housed in one room of the finishing building within the Kirkwood Swine Unit. All the hogs are phase fed on a split-sex schedule and the barrows and gilts are rotated on the phytase diet.
Feed is measured at the beginning and end of every feeding phase.
Liquid manure samples are collected every two weeks from individual pits beneath the control and test groups, and solid manure samples are taken from the slats in the building. Water consumption was measured by the total room capacity for the first trial and is now monitored separately for the control and test groups. McMullen said the water use data is encouraging. Even so, pig performance has been excellent. Initial results show the first test group of barrows gained an average of 2.01 pounds per day compared with 1.95 pounds for the control group of gilts.