Heat Stress, Antioxidant Supplementation and HSP70 mRNA Expression in Growing Pigs

Heat stress poses significant challenges to livestock productivity, particularly in pigs, due to their limited thermoregulatory mechanisms. This study aimed to evaluate the seasonal effects of heat stress on growth performance, haematological and hormonal level, as well as the relative mRNA expression of HSP70 in growing pigs supplemented with melatonin and vitamin E. Results showed that haematological parameters, serum cortisol, lactate dehydrogenase, and average body weight were adversely affected during the summer season. While antioxidant supplementation did not significantly influence haematological profiles or LDH levels, it reduced cortisol levels during summer. Vitamin E supplementation resulted in a significant decrease in HSP70 mRNA expression during summer, indicating improved oxidative stability. Seasonal variations notably affect pigs' growth and health, with vitamin E supplementation reducing HSP70 expression during summer, highlighting the challenges of tropical climates.