EFFECT OF HOT ENVIRONMENT ON CELL-SURFACE DIFFERENTIATION ANTIGENS OF PORCINE PERIPHERAL LYMPHOCYTES FROM SOWS AND LITTERS

1. Rectal temperatures were higher in sows maintained for 28 days following farrowing in a cycling hot environment (27-32-degrees-C, 50-90% RH) than in sows in a cool environment (21-degrees-C, 50% RH). Rectal temperatures in the litters were similar regardless of environment. 2. In sows in the hot environment, the percentages of CD2+ and CD8+ peripheral T lymphocytes and cells expressing SLA class II molecules were reduced, while the percentages of CD4+ cells were not affected. 3. Overall percentages of expression of CD2+ and CD8+ T cells and SLA class II molecules were lower in the litters than in the sows, with expression increasing with age but not significantly affected by temperature.