Pigs were weaned at 4 wk of age and were kept in
littermate groups until they were assigned to treatments.
Males were castrated at 10 to 14 d of age. Pigs
were approximately 6 wk old and weighed 10.8 k .33
kg at the start of the experiment. At the start of the
study, pigs were moved from one room to another and
weighed individually. Blood was collected and pigs
were placed in experimental pens. Subsequent weights
were obtained on d 7, 14, 21, and 28 in the experiment
rooms.