Lactating Sows and Suckling Piglets Preferentially Incorporate RRR- over All-rac-α-Tocopherol into Milk, Plasma and Tissues

Abstract

Synthetic vitamin E, all-rac-alpha-tocopherol, contains eight different stereoisomers, only one of which, RRR-alpha-tocopherol, occurs naturally. The objective of this investigation was to evaluate the relative abilities of these two vitamin E forms to enrich piglet tissues when fed as alpha-tocopheryl acetates to sows during pregnancy and lactation. alpha-Tocopherol delivery to fetuses and to suckling piglets was monitored by feeding 150 mg each of d(3)-RRR-alpha- and d(6)-all-rac-alpha-tocopheryl acetate to three pregnant sows daily from 7 d before to 7 d after giving birth. Labeled and unlabeled vitamin E concentration ratios were measured in sow plasma and milk, and in piglet (n = 9) plasma and tissues at birth, 7 and 21 d. At birth, despite elevated sow plasma deuterated alpha-tocopherol concentrations, no labeled alpha-tocopherol was detected in piglet plasma or tissues. Sow plasma and milk d(3)-alpha- to d(6)-alpha-tocopherol concentrations were 2:1, leading to a 2:1 ratio in suckling piglet plasma and tissues. In piglets at d 7 compared with birth, most tissues contained a 10-fold increase in total alpha-tocopherol; the highest deuterated vitamin E concentrations were in the liver, followed by the lung, heart, kidney, muscle, intestine and brain. In conclusion, pigs discriminate between RRR- and all-rac-alpha-tocopherol with a preference for RRR-alpha-tocopherol; thus, the official bioequivalence ratio of 1.36:1 RRR- to all-rac-alpha-tocopherol is underestimated. After initiation of suckling, piglet plasma and tissues demonstrated a dramatic increase in vitamin E concentrations, emphasizing the limited placental vitamin E transfer and the importance of milk for enhancing the vitamin E status of the newborn.

Effects of oral micellized natural vitamin E (d-α-tocopherol) v. synthetic vitamin E (dl-α-tocopherol) in feed on α-tocopherol levels, stereoisomer distribution, oxidative stress and the immune response in piglets

“…This has been widely reported in the literature and is attributed to increased stress (Lauridsen et al, 2002;Moreira and Mahan, 2002;Wilburn et al, 2008). However, it is interesting to note that the magnitude of the decrease was greatest in groups with higher serum concentrations of α-tocopherol at weaning (P < 0.001, interaction time × treatment; Table 3).…”

“…Those piglets from sows supplemented with the natural source of vitamin E (1/2-NAT-1/2-NAT; 1/2-NAT-15-SINT; 1/3-NAT-1/3-NAT; 1/3-NAT-15-SINT) had higher RRR (P < 0.001) and lower RRS (P < 0.001), RSS (P < 0.001) and RSR (P < 0.001) α-tocopherol stereoisomers proportions at day 39 of age than those from sows supplemented with the synthetic form (30-SINT-1/2-NAT; 30-SINT-1/3-NAT; 30-SINT-15-SINT). Lauridsen et al (2002) previously reported that lactating sows and suckling piglets preferentially incorporate RRRover all-rac-α-tocopherol into milk, plasma and tissues. Hoppe and Krennrich (2000) and Stone et al (2003) found similar results in humans.…”

“…Transfer of α-tocopherol to piglets Piglets suffer a marked decline in α-tocopherol concentration after weaning (Chung et al, 1992;Mahan et al, 2000;Lauridsen et al, 2002). As micellized natural vitamin E (D-α-tocopherol) was expected to be more efficiently accumulated than the synthetic form (Pumfrey et al, 1993;Pagan et al, 2005) and that water consumption would be more consistent than feed intake during the post-weaning period (Wilburn et al, 2008), we designed various strategies to study the effectiveness of supplementing piglets and/or sows with vitamin E. Supplementation ratios to piglets and/or sows were 1 : 1, 1 : 2 and 1 : 3 (natural vitamin E in water: synthetic in feed) trying to find a real equivalence between both forms of vitamin and administration vehicles that minimize piglet serum α-tocopherol decline after weaning.…”

“…There is no information in the literature regarding the effects of sow vitamin E supplementation in drinking water on piglet tissue α-tocopherol levels. According to Lauridsen et al (2002), piglet fat and the brain were the only tissues in which α-tocopherol concentrations increased from 7 to 21 days of lactation when mothers were supplemented. Other investigators have found a tendency for greater vitamin E concentration in piglets of sucking sows receiving high levels of DL-α-tocopheryl acetate (Mahan, 1991;Hiridoglou et al, 1993;Pinelli-Saavedra et al, 2008) or D-α-tocopheryl acetate (Mahan et al, 2000) because of the high absorption from sow's milk.…”

“…It has been demonstrated that sows and piglets (Lauridsen et al, 2002) preferentially accumulated the natural form of vitamin E (RRR-α-tocopherol) over the synthetic form (allrac-α-tocopherol). In addition, micellized natural vitamin E has been found to be more effective at elevating plasma α-tocopherol (Pumfrey et al, 1993;Amazan et al, 2012).…”