The influence of regular physical activity on the cell-mediated immunity in pigs.

The influence of moderate regular physical activity on the cell-mediated immunity was studied in growing pigs. Ten animals were subjected to physical training on a large animal treadmill, and 10 were kept in their pens throughout a 12-week experimental period. Regardless of whether the pigs underwent training or not, a whole blood lymphocyte stimulation test performed at 3 stages of the experiment revealed an equal ability of the cells to respond to stimulation induced by pokeweed mitogen and phytohaemaglutinin. The influence of serum from the pigs of the trained and untrained groups was studied in a stimulation test with purified mononuclear cells obtained from 2 healthy control pigs. The results indicated that no additional serum factors released by the physical training altered the blastogenic response of these lymphocytes. It is concluded that moderate exercise should not be regarded as a stressor which alters the cellular immunity in pigs.