GPX1 and infection: In addition, polyunsaturated fatty acids (PUFAs) which are prone to oxidative reactions, low antioxidative status such as reduced concentration of vitamin E and vitamin C upon weaning of pigs9, and/or impaired synthesis of enzymatic antioxidants (superoxide dismutase (SOD) and glutathione peroxidase-1 (GPX1)) may promote oxidative reactive reactions, and influence the immune response during infection.