Plant-derived polyphenols in sow nutrition: An update

Oxidative stress is a potentially critical factor that affects productive performance in gestating and lactating sows. Polyphenols are a large class of plant secondary metabolites that possess robust antioxidant capacity. All polyphenols are structurally characterized by aromatic rings with multiple hydrogen hydroxyl groups; those make polyphenols perfect hydrogen atoms and electron donors to neutralize free radicals and other reactive oxygen species. In the past decade, increasing attention has been paid to polyphenols as functional feed additives for sows. Polyphenols have been found to alleviate inflammation and oxidative stress in sows, boost their reproductivity, and promote offspring growth and development. In this review, we provided a systematical summary of the latest research advances in plant-derived polyphenols in sow nutrition, and mainly focused on the effects of polyphenols on the (1) antioxidant and immune functions of sows, (2) placental functions and the growth and development of fetal piglets, (3) mammary gland functions and the growth and development of suckling piglets, and (4) the long-term growth and development of progeny pigs. The output of this review provides an important foundation, from more than 8,000 identified plant phenols, to screen potential polyphenols (or polyphenol-enriched plants) as functional feed additives suitable for gestating and lactating sows.