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.

Within-litter variation in birth weight: impact of nutritional status in the sow

Accompanying the beneficial improvement in litter size from genetic selection for high-prolificacy sows, within-litter variation in birth weight has increased with detrimental effects on post-natal growth and survival due to an increase in the proportion of piglets with low birth-weight. Causes of within-litter variation in birth weight include breed characteristics that affect uterine space, ovulation rate, degree of maturation of oocytes, duration of time required for ovulation, interval between ovulation and fertilization, uterine capacity for implantation and placentation, size and efficiency of placental transport of nutrients, communication between conceptus/fetus and maternal systems, as well as nutritional status and environmental influences during gestation. Because these factors contribute to within-litter variation in birth weight, nutritional status of the sow to improve fetal-placental development must focus on the following three important stages in the reproductive cycle： pre-mating or weaning to estrus, early gestation and late gestation. The goal is to increase the homogeneity of development of oocytes and conceptuses, decrease variations in conceptus development during implantation and placentation, and improve birth weights of newborn piglets. Though some progress has been made in nutritional regulation of within-litter variation in the birth weight of piglets, additional studies, with a focus on and insights into molecular mechanisms of reproductive physiology from the aspects of maternal growth and offspring development, as well as their regulation by nutrients provided to the sow, are urgently needed.

Increased maternal consumption of methionine as its hydroxyl analog promoted neonatal intestinal growth without compromising maternal energy homeostasis

Background： To determine responses of neonatal intestine to maternal increased consumption of DL-methionine（DLM） or DL-2-hydroxy-4-methylthiobutanoic acid（HMTBA）, eighteen primiparous sows（Landrace × Yorkshire） were allocated based on body weight and backfat thickness to the control, DLM and HMTBA groups（n = 6）, with the nutritional treatments introduced from postpartum d0 to d14.Results： The DLM-fed sows showed negative energy balance manifested by lost bodyweight, lower plasma glucose, subdued tricarboxylic acid cycle, and increased plasma lipid metabolites levels. Both villus height and ratio of villus height to crypt depth averaged across the small intestine of piglets were higher in the DLM and HMTBA groups than in the control group. Piglet jejunal oxidized glutathione concentration and ratio of oxidized to reduced glutathione were lower in the HMTBA group than in the DLM and control groups. However, piglet jejunal aminopeptidase A, carnitine transporter 2 and IGF-II precursor m RNA abundances were higher in the DLM group than in the HMTBA and control groups.Conclusion： Increasing maternal consumption of methionine as DLM and HMTBA promoted neonatal intestinal growth by increasing morphological development or up-regulating expression of genes responsible for nutrient metabolism. And increasing maternal consumption of HMTBA promoted neonatal intestinal antioxidant capacity without compromising maternal energy homeostasis during early lactation.