IntroductionSuboptimal health of pigs under commercial housingand management conditions is a major factor mitigat-ing against optimum performance (Holck et al., 1998).Chronic immune stimulation (Broussard et al., 2003) frompathogenic attack, environmental and management stress(Brestensky et al., 2012) plays a major role in persistentimmune system activation, resulting in chronic inflam-mation. Despite the well-established negative effects ofimmune activation on several aspects of pig health,the mechanism by which immune stimulation leads toAbbreviations