ABSTRACT: Long-distance transport is associated with stress-related changes in equine immune function, and shipping-associated illnesses are often reported. Horses are frequently transported short distances, yet the effects of short-term transport on immune function remain largely unknown. Twelve horses, aged 15-30 yr, were assigned to either the control (n = 6) or treatment (n = 6) groups; treatment horses received a daily antioxidant supplement 3 weeks before and after transport. All horses were transported for approximately 1.5-2 hr on Day 0. Blood was collected via jugular venipuncture at 15-min pre- and post-transport and on Days -21, 1, 3, 7, 14, and 21. Body temperature, heart rate, body weight, total cortisol, and gene expression of IFNγ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12α, IL-17α,
