Review: Improving the performance of neonatal piglets.

Newborn piglets have a high incidence of preweaning mortality that is not only associated with low birth weights but also with the presence of intra-uterine growth-restricted (IUGR) piglets. Such IUGR piglets are commonly seen in litters from hyperprolific sows as a result of insufficient placental transfer of nutrients. Nutritional strategies can be used prior to and during gestation to enhance foetal development and can also be implemented in the transition period to reduce the duration of farrowing and increase colostrum yield. Recent findings showed that the energy status of sows at the onset of farrowing is crucial to diminish stillbirth rate. Newborn piglets often fail to consume enough colostrum to promote thermostability and subsequent growth, and this is particularly problematic in very large litters when there are fewer available teats than the number of suckling piglets. One injection of 75 IU of oxytocin approximately 14 h after farrowing can prolong the colostral phase, hence increasing the supply of immunoglobulins to piglets. Nevertheless, assistance must be provided to piglets after birth in order to increase their chance of survival. Various approaches can be used, such as: (1) optimising the farrowing environment, (2) supervising farrowing and assisting newborn piglets, (3) using cross-fostering techniques, (4) providing nurse sows, and 5) providing artificial milk. Although research advances have been made in developing feeding and management strategies for sows that increase performance of their newborn piglets, much work still remains to be done to ensure that maximal outcomes are achieved.

Multiscale and multimodal imaging of utero-placental anatomy and function in pregnancy.

Placental structures at the nano-, micro-, and macro scale each play important roles in contributing to its function. As such, quantifying the dynamic way in which placental structure evolves during pregnancy is critical to both clinical diagnosis of pregnancy disorders, and mechanistic understanding of their pathophysiology. Imaging the placenta, both exvivo and invivo, can provide a wealth of structural and/or functional information. This review outlines how imaging across modalities and spatial scales can ultimately come together to improve our understanding of normal and pathological pregnancies. We discuss how imaging technologies are evolving to provide new insights into placental physiology across disciplines, and how advanced computational algorithms can be used alongside state-of-the-art imaging to obtain a holistic view of placental structure and its associated functions to improve our understanding of placental function in health and disease.

Placental Impact of Dietary Supplements: More Than Micronutrients.

PURPOSE: Maternal nutrition is a key modifier of fetal growth and development. However, many maternal diets in the United States do not meet nutritional recommendations. Dietary supplementation is therefore necessary to meet nutritional goals. The effects of many supplements on placental development and function are poorly understood. In this review, we address the therapeutic potential of maternal dietary supplementation on placental development and function in both healthy and complicated pregnancies. METHODS: This is a narrative review of original research articles published between February 1970 and July 2020 on dietary supplements consumed during pregnancy and placental outcomes (including nutrient uptake, metabolism and delivery, as well as growth and efficiency). Impacts of placental changes on fetal outcomes were also reviewed. Both human and animal studies were included. FINDINGS: We found evidence of a potential therapeutic benefit of several supplements on maternal and fetal outcomes via their placental impacts. Our review supports a role for probiotics as a placental therapeutic, with effects that include improved inflammation and lipid metabolism, which may prevent preterm birth and poor placental efficiency. Supplementation with omega-3 fatty acids (as found in fish oil) during pregnancy tempers the negative effects of maternal obesity but may have little placental impact in healthy lean women. The beneficial effects of choline supplementation on maternal health and fetal growth are largely attributable to its placental impacts. l-arginine supplementation has a potent provascularization effect on the placenta, which may underlie its fetal growth-promoting properties. IMPLICATIONS: The placenta is exquisitely sensitive to dietary supplements. Pregnant women should consult their health care practitioner before continuing or initiating use of a dietary supplement. Because little is known about impacts of many supplements on placental and long-term offspring health, more research is required before robust clinical recommendations can be made.

A Matched Cohort Study of Postpartum Placentophagy in Women With a History of Mood Disorders: No Evidence for Impact on Mood, Energy, Vitamin B12 Levels, or Lactation.

OBJECTIVE: Although empirical studies investigating its effects are scarce, postpartum placentophagy is increasing in popularity because of purported benefits on mood, energy, lactation, and overall nutrition. Therefore, this study sought to test the hypotheses that women who consumed their placenta (placentophagy exposed [PE]) would have (1) fewer depressive symptoms, (2) more energy, (3) higher vitamin B12 levels, and (4) less pharmaceutical lactation support during the postpartum than women who did not consume their placenta (non-placentophagy exposed [NE]). METHODS: Using data from a large, longitudinal study of gene × environment effects involving perinatal women with a history of mood disorders, the study investigators identified a PE cohort and matched them 4:1 (by psychiatric diagnosis, psychotropic medication use, supplementation, income, and age) with an NE cohort from the same dataset. The study investigated differences between the PE and NE cohorts with respect to scores on the Edinburgh Postnatal Depression Scale and Sleep-Wake Activity Inventory, vitamin B12 levels, and the use of pharmaceutical lactation support (Canadian Taskforce Classification II-2). RESULTS: The sample of 138 women (28 in the PE cohort, matched to 110 in the NE cohort) provided 80% power at α = 0.0125 to detect an effect of moderate magnitude (which can be used to approximate an effect of clinically significant magnitude).There were no differences in Edinburgh Postnatal Depression Scaleor Sleep-Wake Activity Inventory scales (P = 0.28 and P = 0.39, respectively), vitamin B12 levels (P = 0.68), or domperidone use (P = 1) between the PE and NE cohorts. CONCLUSION: These data provide no support for the idea that postpartum placentophagy improves mood, energy, lactation, or plasma vitamin B12 levels in women with a history of mood disorders.

Development and Entrainment of the Fetal Clock in the Suprachiasmatic Nuclei: The Role of Glucocorticoids.

The adult circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus is resilient to glucocorticoids (GCs). The fetal rodent SCN resembles that of the adult in its organization of GC-sensitive peripheral tissues. We tested the hypothesis that the fetal SCN clock is sensitive to changes in GC levels. Maternal GCs must pass through the placenta to reach the fetal SCN. We show that the maternal but not the fetal part of the placenta harbors the autonomous circadian clock, which is reset by dexamethasone (DEX) and rhythmically expresses Hsd11b2. The results suggest the presence of a mechanism for rhythmic GC passage through the placental barrier, which is adjusted according to actual GC levels. GC receptors are expressed rhythmically in the laser-dissected fetal SCN samples. We demonstrate that hypothalamic explants containing the SCN of the mPer2 Luc mouse prepared at embryonic day (E)15 spontaneously develop rhythmicity within several days of culture, with dynamics varying among fetuses from the same litter. Culturing these explants in media enriched with DEX accelerates the development. At E17, treatment of the explants with DEX induces phase advances and phase delays of the rhythms depending on the timing of treatments, and the shifts are completely blocked by the GC receptor antagonist, mifepristone. The DEX-induced phase-response curve differs from that induced by the vehicle. The fetal SCN is sensitive to GCs in vivo because DEX administration to pregnant rats acutely downregulates c-fos expression specifically in the laser-dissected fetal SCN. Our results provide evidence that the rodent fetal SCN clock may respond to changes in GC levels.

Omega-3 Long-Chain Polyunsaturated Fatty Acids and Preeclampsia: Trials Say "No," but Is It the Final Word?

Preeclampsia is a dangerous disorder of pregnancy, defined as hypertension with proteinuria. Its nature remains elusive, and measures of prevention and treatment are limited. Observational studies have suggested that preeclampsia is associated with low intake of omega-3 long-chain polyunsaturated fatty acids (LCPUFA). In recent decades, researchers studied LCPUFA supplementation as a measure to prevent preeclampsia. Most of these trials and later systematic reviews yielded negative results. However, these trials had several important limitations associated with heterogeneity and other issues. Recent research suggests that preeclampsia trials should take into consideration the gender of the fetus (and thus sexual dimorphism of placenta), the positive effect of smoking on preeclampsia prevalence, and the possibility that high doses of LCPUFA mid-term or later may promote the disorder instead of keeping it at bay. In this review, we discuss these issues and future prospects for LCPUFA in preeclampsia research.

Pravastatin to treat and prevent preeclampsia. Preclinical and clinical studies.

Pre-eclampsia is a disease of pregnancy affecting 5%-8% of all pregnancies and a leading cause of maternal and fetal mortality. Despite improvements in the diagnosis, there is no effective method for prevention and treatment. While studies in women are of critical importance, investigation of pathological mechanisms in pregnant women is necessarily limited, and the ability to establish cause and effect relationships, difficult. Mouse models have been instrumental in defining pathogenic mechanisms in preeclampsia and in the identification of pravastatin as a potential treatment to prevent pregnancy complications associated with placental dysfunction. Numerous epidemiological studies provided robust evidence demonstrating that pravastatin exposure during pregnancy does not affect fetal development. In addition, pravastatin is hydrophilic and has a limited passage through the placenta, diminishing any safety concerns. Several pilot studies suggest that pravastatin may be a good option to prevent and treat preeclampsia in women. While these studies are promising, the effectiveness of pravastatin to treat preeclampsia needs to be confirmed by randomized clinical trials.

Effects of oil quality and antioxidant supplementation on sow performance, milk composition and oxidative status in serum and placenta.

BACKGROUND: The aim of this study was to determine the effects of oil quality and antioxidant (AOX) supplementation on sow performance, milk composition and oxidative status. METHODS: A total of 80 PIC (PIC breeding, 3 ~ 5 parities) sows with similar body condition were allocated to four groups (n = 20), receiving diets including fresh corn oil, oxidized corn oil, fresh corn oil plus AOX and oxidized corn oil plus AOX, respectively, from d 85 of gestation to d 21 of lactation. AOX was provided at 200 mg/kg diet and mixed with corn oil prior to dietary formulation. RESULTS: The results showed that sows fed oxidized corn oil had significantly lower feed intake (P < 0.05) during lactation period. Feeding oxidized corn oil markedly decreased (P < 0.05) the contents of protein and fat in colostrums and milk, but the addition of AOX in oxidized corn oil prevented the decrease on protein content of colostrums. Moreover, sows fed oxidized corn oil had significantly lower serum activities of total SOD and Mn-SOD across lactation (P < 0.05). In contrast, addition of AOX to oxidized corn oil tended to inhibit the production of MDA (P = 0.08) in sows across lactation relative to fresh oil. Intriguingly, the placental oxidative status was affected by oil quality and AOX supplementation, as indicated by the markedly increased placental gene expression of GPX and SOD (P < 0.05) in sows fed oxidized corn oil but normalized by supplementation of AOX. CONCLUSION: In conclusion, feeding oxidized corn oil did not markedly affect reproductive performance in addition to decreasing feed intake during lactation. Milk composition and systemic oxidative status were deteriorated in sows fed oxidized corn oil and partially improved by AOX supplementation. Moreover, placental antioxidant system of sows may have an adaptive response to oxidative stress, but normalized by AOX.

Cobalamin supplementation during in vitro maturation improves developmental competence of sheep oocytes.

Pregnancies obtained by Assisted Reproductive Technologies are at higher risk of miscarriage than those obtained naturally. Previously, we reported impaired placental vascular development of in vitro produced (IVP) sheep embryos and defective DNA methylation in the placentae of those embryos. One reason behind these observed defects may be an impaired One Carbon Metabolism (OCM) The present study was performed to test the hypothesis that Cobalamin (Vitamin B12, an important OCM co-factor) supplementation during IVM corrects DNA methylation of IVP embryos and, consequently, ameliorates placental vasculogenesis. To this aim, embryos derived from oocytes matured with Cobalamin (B12 group) or without (negative control group, -CTR) were transferred to synchronized recipient sheep. At day 20 of pregnancy, collected embryos were morphologically evaluated while placentae were subjected to qPCR and histological analysis. The positive control group (+CTR) consisted of conceptuses obtained from naturally mated sheep. Results showed an increased fertilization rate in the B12 group vs -CTR (69.56% vs 57.91% respectively, P = 0.006) not associated with quantitative improvement in blastocyst and/or implantation rate (44.32% vs 36.67% respectively, P > 0.05). Moreover, Cobalamin supplementation during oocyte IVM ameliorated resulting conceptuses quality, in terms of placental vascularization (vessels' maturity and vasculogenetic factors' expression). The expression of DNA methyltransferases (DNMT1, DNMT3A and DNMT3B) was also improved in placentae from the B12 group. In conclusion, Cobalamin supplementation during oocyte IVM improves IVP embryo quality. These results suggest that Cobalamin should be included in standard IVM media.

Dietary interventions for fetal growth restriction - therapeutic potential of dietary nitrate supplementation in pregnancy.

Fetal growth restriction (FGR) affects around 5% of pregnancies and is associated with significant short- and long-term adverse outcomes. A number of factors can increase the risk of FGR, one of which is poor maternal diet. In terms of pathology, both clinically and in many experimental models of FGR, impaired uteroplacental vascular function is implicated, leading to a reduction in the delivery of oxygen and nutrients to the developing fetus. Whilst mechanisms underpinning impaired uteroplacental vascular function are not fully understood, interventions aimed at enhancing nitric oxide (NO) bioavailability remain a key area of interest in obstetric research. In addition to endogenous NO production from the amino acid l-arginine, via nitric oxide synthase (NOS) enzymes, research in recent years has established that significant NO can be derived from dietary nitrate, via the 'alternative NO pathway'. Dietary nitrate, abundant in green leafy vegetables and beetroot, can increase NO bioactivity, conferring beneficial effects on cardiovascular function and blood flow. Given the beneficial effects of dietary nitrate supplementation to date in non-pregnant humans and animals, current investigations aim to assess the therapeutic potential of this approach in pregnancy to enhance NO bioactivity, improve uteroplacental vascular function and increase fetal growth.

Review: Effects of maternal micronutrient supplementation on placental function.

Pregnancy is a physiological challenge that may require additional nutritional support. Suboptimal micronutrient intakes and micronutrient deficiencies during pregnancy are a global problem, often leading to poor maternal and child outcomes. Micronutrient supplementation is commonly recommended during pregnancy to support and enhance maternal metabolism. Recent studies suggest that the use of multiple micronutrient supplements may be of benefit during a normal pregnancy and may significantly reduce the risk of preeclampsia, preterm delivery, gestational diabetes, and improve pregnancy outcomes. Given the crucial role that the placenta plays in mediating pregnancy outcomes, it is important to consider the impact of micronutrient supplementation on the mechanisms associated with placental function, as well as maternal and fetal homeostasis. This review will consider the role of key micronutrients in supporting pregnancy and the possible mechanisms by which multiple micronutrients influence placental function and modulate placental oxidative stress and inflammation.

RAPID COMMUNICATION: Expression of an endogenous retroviral element, during early gestation in beef heifers.

Endogenous retroviral gene elements have been implicated in development and formation of the feto-maternal interface. A variant of the syncytin endogenous retroviral envelope gene family, , was recently found in ruminants. We hypothesized that mRNA would be differentially expressed in utero-placental tissues and would fluctuate during key time points of early gestation in beef heifers. Commercial Angus crossbred heifers ( = 46; ∼15 mo of age; BW = 362.3 ± 34.7kg) housed in 6-animal pens were fed daily with native grass hay and supplemented with cracked corn to gain 0.3 kg/d. The heifers were estrus synchronized, artificially inseminated, (d of breeding= d 0) and ovariohysterectomized on d 16, 22, 28, 34, 40, and 50 ( = 9, 6, 6, 7, 6, and 5, respectively) of gestation and at d 16 of the estrous cycle for non-bred, non-pregnant controls (NP; = 7). Harvested tissues were separated into maternal caruncle (CAR), intercarunclar endometrium (ICAR), and fetal membranes, (FM; chorioallantois, d 22 and later). All tissues were obtained from the ipsilateral uterine horn to the CL. Statistical analyses were conducted via the GLM procedure of SAS. Maternal CAR expression of was greater ( = 0.003) on d 50 by 81.5-fold compared to NP controls. At d 50 expression of in CAR was 190.3-fold greater than ( < 0.0001) ICAR. Fetal membranes had greater ( < 0.002) expression of from d 22 until d 50 of gestation compared to maternal ICAR (d 16 not analyzed). Expression of in FM was greater ( < 0.004) than in CAR until d 40 of gestation. Therefore, we conclude that is differentially expressed in utero-placental tissues and may be involved in the establishment of pregnancy. The expression of in maternal tissues is completely novel and indicates unique functions of syncytin in ruminant pregnancy.

N-carbamylglutamate and L-arginine improved maternal and placental development in underfed ewes.

The objectives of this study were to determine how dietary supplementation of N-carbamylglutamate (NCG) and rumen-protected L-arginine (RP-Arg) in nutrient-restricted pregnant Hu sheep would affect (1) maternal endocrine status; (2) maternal, fetal, and placental antioxidation capability; and (3) placental development. From day 35 to day 110 of gestation, 32 Hu ewes carrying twin fetuses were allocated randomly into four groups: 100% of NRC-recommended nutrient requirements, 50% of NRC recommendations, 50% of NRC recommendations supplemented with 20g/day RP-Arg, and 50% of NRC recommendations supplemented with 5g/day NCG product. The results showed that in maternal and fetal plasma and placentomes, the activities of total antioxidant capacity and superoxide dismutase were increased (P<0.05); however, the activity of glutathione peroxidase and the concentration of maleic dialdehyde were decreased (P<0.05) in both NCG- and RP-Arg-treated underfed ewes. The mRNA expression of vascular endothelial growth factor and Fms-like tyrosine kinase 1 was increased (P<0.05) in 50% NRC ewes than in 100% NRC ewes, and had no effect (P>0.05) in both NCG- and RP-Arg-treated underfed ewes. A supplement of RP-Arg and NCG reduced (P<0.05) the concentrations of progesterone, cortisol, and estradiol-17ß; had no effect on T4/T3; and improved (P<0.05) the concentrations of leptin, insulin-like growth factor 1, tri-iodothyronine (T3), and thyroxine (T4) in serum from underfed ewes. These results indicate that dietary supplementation of NCG and RP-Arg in underfed ewes could influence maternal endocrine status, improve the maternal-fetal-placental antioxidation capability, and promote fetal and placental development during early-to-late gestation.

Positive and negative gestational handling influences placental traits and mother-offspring behavior in dairy goats.

Dairy animals are subjected to a number of potential stressors throughout their lives, including daily interactions with humans. The quality of these interactions may have direct consequences for the animal undergoing the experience, but if such events occur during gestation it may also affect the developing fetus. This study examined the effects of differential handling during mid-gestation in 40 twin-bearing Saanen×Toggenburg primiparous goats. Between days 80 and 115 of gestation (gestation=150 days), goats were subjected to aversive (AVS, n=13), gentle (GEN, n=13) or minimal (M, n=14) handling protocols for 10 minute periods twice daily. The control (M) group did not receive handling treatments and all goats received normal husbandry procedures outside treatment periods. Salivary cortisol measured during the treatment period was higher in AVS goats (mean cortisol (sem) in pg/µl: AVS: 176.7 (18.2), GEN: 119.6 (11.1), M: 126.5 (13.7); P=0.007). Data collection was focussed on mother-offspring behaviors 2h post-partum, placental morphology and colostrum quality. AVS goats were the only treatment group to suffer fetal loss (16% loss vs 0% in GEN and M, P=0.05). Treatment also influenced placental morphology with a tendency for fewer cotyledons evident in placentae from the aversive treatment (AVS: 87.9 (7.8), GEN: 107.1 (7.9), M: 112.1 (9.3), P=0.093), and significantly fewer medium sized cotyledons (AVS: 67.6 (7.8), GEN: 89.3 (6.4), M: 84.3 (5.4), P=0.042). GEN goats displayed more grooming and nosing behaviors towards their young during the first 2h post-partum (grooming: GEN: 89.3% (7.1), AVS: 72.6% (7.7), M: 63.4% (9.0), P=0.045; nosing frequency: GEN: 58.8 (12.5), AVS: 28.6 (11.1), M: 34.7 (6.5), P=0.021). There was an overall trend for kids from mothers experiencing the AVS treatment to take longer to stand, reach the udder and suck compared to kids from GEN and M treatment groups. Treatment significantly affected latency to perform play behavior, with kids from AVS goats taking on average 25 min longer to play for the first time than kids from GEN and M treatment groups (P<0.001). The results show that handling during gestation affects placental morphology, fetal survival and post-partum maternal behaviors, and influences kid behavioral development. Such results have important animal welfare implications, demonstrating that negative handling of pregnant females results in poorer placental quality with potential for fetal loss. It also demonstrates the beneficial effects of positive handling on enhancement of maternal behaviors.

Consumption of the Placenta in the Postpartum Period.

Postpartum women are consuming their placentas to achieve claimed health benefits, including improved mood, energy, and lactation. Strong scientific evidence to substantiate these claims is lacking. Self-reported benefits from some women include improved mood and lactation; animal models suggest there may be an analgesic effect. Possible risks include infection, thromboembolism from estrogens in placental tissue, and accumulation of environmental toxins. Women's health care providers should be aware of this practice to help women make informed decisions.

The oxytocin-CD38-vitamin A axis in pregnant women involves both hypothalamic and placental regulation.

OBJECTIVE: Oxytocin, a hypothalamic hormone secreted upon release of ectoenzyme CD38, plays a vital role in interpersonal bonding behaviors. Reduced plasma oxytocin characterizes autistic individuals. CD38 levels, which were found to be low in LBCs derived from autistic patients, is upregulated upon the addition of a vitamin A derivative. During pregnancy, oxytocin is also secreted by placenta. Recent controversial studies have suggested an increased risk for autism when oxytocin is used during induction and augmentation of labor. We aimed to examine the tripartite relationship between oxytocin, CD38 and vitamin A in pregnant women and their newborns. METHODS: Thirty-one healthy expectant mothers were enlisted for this study. Levels of oxytocin, CD38 and ATRA were measured in both maternal peripheral and newborn cord blood, and the tripartite relationship between these parameters examined. Estrogen and progesterone levels of the mothers were also recorded. Several clinical measures were also noted. RESULTS: Mean maternal oxytocin and vitamin A levels were approximately 8- and 4-fold higher, respectively, than neonatal levels. CD38 expression, however, was 9 times higher in neonates than in the maternal group. Positive correlation was found between maternal and cord blood for both oxytocin and CD38. CONCLUSIONS: This establishment of normative values for oxytocin, CD38 and vitamin A in healthy pregnant women and newborns may serve as a reference in the investigation of developing pathologies of disorders such as autism.

Amino acids in sheep production.

Increasing production efficiency with a high standard of animal welfare and respect for the environment is a goal of sheep farming systems. Substantial gains in productivity have been achieved through improved genetics, nutrition and management changes; however the survival and growth performance of multiple-born lambs still remains a problem. This is a significant production efficiency and animal well-being issue. There is a growing body of evidence that some amino acids have a role in regulating growth, reproduction and immunity through modulation of metabolic and cell signaling pathways. The purpose of this review is to provide an overview of what is currently known about the role of amino acids in sheep production and the potential for supplementation strategies to influence on-farm survival and growth of lambs.

Maternal dietary omega-3 fatty acids and placental function.

The developing fetus requires substantial amounts of fatty acids to support rapid cellular growth and activity. Although the fatty acid composition delivered to the fetus is largely determined by maternal circulating levels, the placenta preferentially transfers physiologically important long-chain polyunsaturated fatty acids (LC-PUFAs), particularly omega-3 (n-3) PUFAs. Maternal dietary supplementation with n-3 PUFAs during pregnancy has been shown to increase gestation length, enhance fetal growth, and reduce the risk of pregnancy complications, although the precise mechanisms governing these effects remain uncertain. Omega-3 PUFAs are involved in several physiological pathways which could account for these effects, including anti-inflammatory, pro-resolving, and anti-oxidative pathways. Recent studies have shown that maternal dietary n-3 PUFA supplementation during rat pregnancy can reduce placental oxidative damage and increase placental levels of pro-resolving mediators, effects associated with enhanced fetal and placental growth. Because several placental disorders, such as intrauterine growth restriction, preeclampsia, and gestational diabetes mellitus, are associated with heightened placental inflammation and oxidative stress, there is considerable interest in the potential for dietary n-3 PUFAs as a therapeutic intervention for these disorders. In this study, we review the impact of dietary n-3 PUFAs on placental function, with particular focus on placental inflammation, inflammatory resolution, and oxidative stress.

Dietary selenium and nutritional plane alter specific aspects of maternal endocrine status during pregnancy and lactation.

Objectives were to examine effects of selenium (Se) supply and maternal nutritional plane during gestation on placental size at term and maternal endocrine profiles throughout gestation and early lactation. Ewe lambs (n = 84) were allocated to treatments that included Se supply of adequate Se (ASe; 11.5 µg/kg BW) or high Se (HSe; 77 µg/kg BW) initiated at breeding and nutritional plane of 60% (RES), 100% (CON), or 140% (EXC) of requirements beginning on day 40 of gestation. At parturition, lambs were removed from their dams, and ewes were transitioned to a common diet that met requirements of lactation. Blood samples were taken from a subset of ewes (n = 42) throughout gestation, during parturition, and throughout lactation to determine hormone concentrations. Cotyledon number was reduced (P = 0.03) in RES and EXC ewes compared with CON ewes. Placental delivery time tended (P = 0.08) to be shorter in HSe ewes than in ASe ewes, whereas placental delivery time was longer (P = 0.02) in RES ewes than in CON and EXC ewes. During gestation, maternal progesterone, estradiol-17ß, and GH were increased (P < 0.05) in RES ewes and decreased (P < 0.05) in EXC ewes compared with CON ewes. In contrast, maternal cortisol, IGF-I, prolactin, triiodothyronine, and thyroxine were decreased in RES ewes and increased in EXC ewes compared with CON ewes during gestation. Selenium supply did not alter maternal hormone profiles during gestation. During parturition and lactation, maternal hormone concentrations were influenced by both Se and maternal nutritional plane. During the parturient process, HSe ewes tended to have greater (P = 0.06) concentrations of estradiol-17ß than ASe ewes. Three hours after parturition a surge of GH was observed in ASe-RES ewes that was muted in HSe-RES ewes and not apparent in other ewes. Growth hormone area under the curve during the parturient process was increased (P < 0.05) in ASe-RES vs HSe-RES ewes. Ewes that were overfed during gestation had reduced (P < 0.05) estradiol-17ß but greater IGF-I, triiodothyronine, and thyroxine (P < 0.05) compared with RES ewes. Even though ewes were transitioned to a common diet after parturition, endocrine status continued to be affected into lactation. Moreover, it appears that gestational diet may partially affect lactational performance through altered endocrine status.

Maternal dietary omega-3 fatty acid supplementation reduces placental oxidative stress and increases fetal and placental growth in the rat.

Placental oxidative stress plays a key role in the pathophysiology of several placenta-related disorders including intrauterine growth restriction. Oxidative stress occurs when accumulation of reactive oxygen species damages DNA, proteins, and lipids, an outcome normally limited by antioxidant defenses. Dietary supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFAs) may limit oxidative stress by increasing antioxidant capacity, but n-3 PUFAs are also highly susceptible to lipid peroxidation; so n-3 PUFA supplementation is potentially harmful. Here we examined the effect of n-3 PUFAs on placental oxidative stress and on placental and fetal growth in the rat. We also investigated whether diet-induced changes in maternal plasma fatty acid profiles are associated with comparable changes in placental and fetal tissues. Rats were fed either standard or high n-3 PUFA diets from Day 1 of pregnancy, and tissues were collected on Day 17 or 22 (term = Day 23). Dietary supplementation with n-3 PUFAs increased fetal (6%) and placental (12%) weights at Day 22, the latter attributable primarily to growth of the labyrinth zone (LZ). Increased LZ weight was accompanied by reduced LZ F(2)-isoprostanes (by 31% and 11% at Days 17 and 22, respectively), a marker of oxidative damage. Maternal plasma PUFA profiles were altered by dietary fatty acid intake and were strongly predictive of corresponding profiles in placental and fetal tissues. Our data indicate that n-3 PUFA supplementation reduces placental oxidative stress and enhances placental and fetal growth. Moreover, fatty acid profiles in the mother, placenta, and fetus are highly dependent on dietary fatty acid intake.