Mid Gestation Research Articles

Abstract 17290: Tead1 is Required for Cardiomyocyte Proliferation

Introduction: Mammalian cardiomyocyte (CM) proliferation peaks in the embryonic and neonatal periods. TEAD1, a key transcription factor regulated by the Hippo pathway, is critical for early embryonic CM proliferation. But mid gestation lethality of Tead1 germline deletion precluded the study of its role in CMs at later developmental stages. We recently generated Tead1 floxed (Tead1 F/F ) mice which allows the study of TEAD1 function in CMs at later stages. The objective of this study was to determine requirement of TEAD1 for neonatal CM proliferation. Hypothesis: TEAD1 remains critical for CM proliferation in late embryonic and early neonatal periods through transcriptional regulation of cell cycle promoting genes. Methods and Results: We observed that TEAD1 cardiac expression peaks in the perinatal period. Using Myh6-Cre deletor mice, we knocked out Tead1 in CMs at E10.5 (referred as cKO). cKO pups were born in expected Mendelian frequency, but survived only till day of life (DOL) 9. Systolic dysfunction was evident by ECHO in DOL1 cKO pups and progressed to frank heart failure (HF) by DOL9. Histological exam showed decreased myocardial mass with increased intercellular fibrosis. Ventricles of DOL1 cKO pups demonstrated increased expression of Acta1, Nppa, and Nppb, consistent with HF but showed decreased expression of Myh7, suggesting an impairment in the typical fetal gene program activated in HF. Myocardial immunostaining showed reduction in Ki67 (G1/S/G2/M phase marker) (Fig 1) and PH3-S10 (M phase marker) positive CMs by 82% and 46% respectively in DOL1 cKO hearts, indicating significantly reduced CM proliferation. The expression of essential cell cycle proteins showed a significant decrease in the levels of G1/S regulating proteins, CDK4, CDK6, ppRB S807/811 and S/G2 and G2/M regulating proteins, pWEE1 S642 and Cyclin B1 in cKO hearts (Fig 2). Similar results in ex vivo and in vitro Tead1 knockout models in CMs using neonatal Tead1 F/F CMs and HL1 cells validated the cell autonomous regulation of CM cell cycle by TEAD1. Conclusions: TEAD1 is required for embryonic and neonatal CM proliferation and its loss at mid gestation leads to neonatal HF associated with impaired fetal gene program activation and decreased expression of cell cycle promoting genes.

Hypoxia causes reductions in birth weight by altering maternal glucose and lipid metabolism

Hypoxia of residence at high altitude (>2500 m) decreases birth weight. Lower birth weight associates with infant mortality and morbidity and increased susceptibility to later-in-life cardiovascular and metabolic diseases. We sought to determine the effects of hypoxia on maternal glucose and lipid metabolism and their contributions to fetal weight. C57BL6/NCrl mice, housed throughout gestation in normobaric hypoxia (15% oxygen) or normoxia, were studied at mid (E9.5) or late gestation (E17.5). Fetal weight at E17.5 was 7% lower under hypoxia than normoxia. The hypoxic compared with normoxic dams had ~20% less gonadal white adipose tissue at mid and late gestation. The hypoxic dams had better glucose tolerance and insulin sensitivity compared with normoxic dams and failed to develop insulin resistance in late gestation. They also had increased glucagon levels. Glucose uptake to most maternal tissues was ~2-fold greater in the hypoxic than normoxic dams. The alterations in maternal metabolism in hypoxia were associated with upregulation of hypoxia-inducible factor (HIF) target genes that serve, in turn, to increase glycolytic metabolism. We conclude that environmental hypoxia alters maternal metabolism by upregulating the HIF-pathway, and suggest that interventions that antagonize such changes in metabolism in high-altitude pregnancy may be helpful for preserving fetal growth.

Emergency cerclage in twins during mid gestation may have favorable outcomes: Results of a retrospective cohort

PurposeCervical cerclage treatment for cervical changes at mid trimester is a very controversial topic in twins. The aim of the study was to present our maternal and fetal outcomes of mid-trimester cervical cerclage in twin pregnancies. Basic proceduresThis study was performed using data extracted from the medical files of the twin pregnancies whom performed emergency cervical cerclage between January 2012 and March 2018 at Trakya University, Facuty of Medicine, Department of Perinatology. Main findingsMean (min.–max.) gestational age at delivery was [27.3 (21–34) weeks]. The median time between cervical cerclage and delivery was 6.4 weeks, while the maximum prolongation of the pregnancy was 11 weeks. The median prolongation period of pregnancy was 4.1 weeks in patients with bulging membranes, but 10 weeks in patients with cervical effacement and cervical shortening.Eight infants died at the neonatal period. Two patients (20%) developed late abortions at 21 and 22 weeks of gestation, and 2 women (20%) delivered extremely premature neonates at the 24th weeks. Overall neonatal mortality rate was 40% (8/20 neonates). Twelve out of twenty were born alive (60%). Principal conclusionsDespite the lack of randomized controlled trials, it seems reasonable to offer emergency cervical cerclage to twin pregnancies with cervical shortening (<15mm). For the twin pregnancies with advanced cervical dilatation and protruding membranes, emergency cervical cerclage should be an option only for carefully selected patients after informing about the complications and low success rate.

Maternal immune activation in mid-late gestation alters amphetamine sensitivity and object recognition, but not other schizophrenia-related behaviours in adult rats

Maternal immune activation induced by Poly(I:C) administration is one of the most commonly used animal models of schizophrenia at present. Previous work from our team has demonstrated that some, but not all of the features often reported for maternal immune activation exposure in rodents can be observed in rats exposed to maternal immune activation at mid or late gestation. To determine whether previous findings in our laboratory were due to these time points simply being less sensitive neurodevelopmental periods for rats with regard to maternal immune activation effects, we aimed to investigate whether maternal immune activation at an often-reported sensitive period (mid-late gestation, day 14) resulted in more behavioural features reflective of face validity for schizophrenia. We examined the behavioural outcomes of mid-late maternal immune activation on a battery of behavioural tests aimed at assessing validity for positive, negative and cognitive symptoms of schizophrenia. We found that rats exposed to maternal immune activation, compared to controls, exhibited enhanced sensitivity to the locomotor-stimulating effects of amphetamine and reduced exploration of novel objects. These findings present a unique profile of effects, different to what has already been established for the same time point in rats, and different to what we had found at earlier and later time points. This work, among others in the literature, highlights the varying nature of models of maternal immune activation and we submit that it is essential for laboratories to characterise their models of maternal immune activation on behaviour rather than assuming that the effects from one laboratory apply in their own.

Sexual dimorphism of mitochondrial function in the hypoxic guinea pig placenta.

Placental hypoxia can stimulate oxidative stress and mitochondrial dysfunction reducing placental efficiency and inducing fetal growth restriction (FGR). We hypothesized that chronic hypoxia inhibits mitochondrial function in the placenta as an underlying cause of cellular mechanisms contributing to FGR. Pregnant guinea pigs were exposed to either normoxia (NMX) or hypoxia (HPX; 10.5% O2) at 25 day gestation until term (65 day). Guinea pigs were anesthetized, and fetuses and placentas were excised at either mid (40 day) or late gestation (64 day), weighed, and placental tissue stored at -80°C until assayed. Mitochondrial DNA content, protein expression of respiratory Complexes I-V, and nitration and activity rates of Complexes I and IV were measured in NMX and HPX male (N=6 in each treatment) and female (N=6 in each treatment) placentas. Mitochondrial density was not altered by HPX in either mid- or late-term placentas. In mid gestation, HPX slightly increased expression of Complexes I-III and V in male placentas only, but had no effect on either Complex I or IV activity rates or nitrotyrosine expression. In late gestation, HPX significantly decreased CI/CIV activity rates and increased CI/CIV nitration in male but not female placentas exhibiting a sexual dimorphism. Complex I-V expression was reduced from mid to late gestation in both male and female placentas regardless of treatment. We conclude that chronic HPX decreases mitochondrial function by inhibiting Complex I/IV activity via increased peroxynitrite in a sex-related manner. Further, there may be a progressive decrease in energy metabolism of placental cell types with gestation that increases the vulnerability of placental function to intrauterine stress.

Maternal Cortisol Concentrations During Pregnancy and Sex-Specific Associations With Neonatal Amygdala Connectivity and Emerging Internalizing Behaviors

BackgroundMaternal cortisol during pregnancy has the potential to influence rapidly developing fetal brain systems that are commonly altered in neurodevelopmental and psychiatric disorders. Research examining maternal cortisol concentrations across pregnancy and offspring neurodevelopment proximal to birth is needed to advance understanding in this area and lead to insight into the etiology of these disorders. MethodsParticipants were 70 adult women recruited during early pregnancy and their infants born after 34 weeks gestation. Maternal cortisol concentrations were assessed serially over 4 days in early, mid, and late gestation. Resting state functional connectivity magnetic resonance imaging of the neonatal amygdala was examined. Mothers reported on children’s internalizing behavior problems at 24 months of age. ResultsMaternal cortisol concentrations during pregnancy were significantly associated with neonatal amygdala connectivity in a sex-specific manner. Elevated maternal cortisol was associated with stronger amygdala connectivity to brain regions involved in sensory processing and integration, as well as the default mode network in girls, and with weaker connectivity to these brain regions in boys. Elevated maternal cortisol was associated with higher internalizing symptoms in girls only, and this association was mediated by stronger neonatal amygdala connectivity. ConclusionsNormative variation in maternal cortisol during pregnancy is associated with the coordinated functioning of the amygdala soon after birth in a sex-specific manner. The identified pathway from maternal cortisol to higher internalizing symptoms in girls via alterations in neonatal amygdala connectivity may be relevant for the etiology of sex differences in internalizing psychiatric disorders, which are more prevalent in women.

Expression of immune regulatory genes in early, mid and late stages of pig (Sus scrofa domesticus) gestation

Semi-allogeneic foetus and placenta exploit various mechanisms to avoid immune-mediated maternal rejection. Several factors and cytokines are attributed for production of immune tolerance during gestation and very little information on expression of these immune-regulatory genes is available in pig. Chorioallantoic membrane (CAM) from early, mid and late gestational stages (n=4) were analysed for expression of immune regulatory genes, viz. Fas ligand (FasL), transporter for antigen processing-1 (TAP-1), transforming growth factor β1 (TGF-β1) and macrophage migration inhibitory factor (MIF) whereas Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was employed as housekeeping gene. FasL gene expression was significantly higher in mid (13.46 fold) and late (28.77 fold) gestation than the early (1 fold) stage.TAP-1 mRNA expression was enhanced by 4.95 fold and 2.69 fold during mid and late gestation respectively in comparison to the early (1 fold) stage. TGF-β1 gene expression was up regulated in mid (2.43 fold) and late (2.29 fold) gestation than the early (1 fold) stage. MIF mRNA expression was enhanced in mid (3.04 fold) and late (1.59 fold) gestation in relation to the early (1 fold) stage. Placenta of pig remains entirely epitheliochorial which may minimise immune recognition and is supposed to diminish potent immune-regulatory mechanisms. However, our present study revealed consistent expression for immune regulatory factors which suggests immune modulation does exist in pig and may impart a role in pregnancy success.

Hydrallantois Associated with Fetal Anasarca in a Non-Descript Doe

The incidence of dystocia in goats has been reported about 7% (Abdul-Rahman et al., 2000) to 8.23 % (Mehta et al., 2002). Fetal causes of dystocia are more common than maternal causes in goat (Abdul-Rahman et al., 2000) and sheep (Taha et al., 2005). Among dropsical conditions, the hydrallantois is more common compared to hydramnios (Hafez, 1993) and is frequently reported in bovines (having twins), rarely in mares (Milton et al., 1989) and less frequently in small ruminants. Hydrallantois is excessive accumulation of fluid in the allantoic sac in uterus, usually occurs within 5 to 20 days in advance pregnancy. Goats suffering from hydrallantois are usually presented in their second stage of labor with a history of sudden enlargement of the abdomen after mid gestation (Purohit, 2006). The present report documents a case of hydrallantois associated with fetal anasarca and its successful management in a non-descript doe.

Dynamic changes in immune populations at the fetomaternal interface during term and preterm birth

Abstract The biologic mechanisms by which birth is initiated are unknown. Recent evidence suggests that the immune system may modulate gestational length. We previously established that maternal immune cells enter the placenta by mid gestation and change in composition near term. We hypothesize that preterm birth also involves immunologic alterations at the fetomaternal interface. To test this hypothesis, we used an established model of inflammation-induced preterm birth. Pregnant mice received intrauterine injections (IUI) of lipopolysaccharide (LPS) (250μg/100μl) (N=8) or saline (100μl) (N=7) on embryonic day 15 (E15). Control mice, without IUI, were sacrificed on E15 (N=7) and E19 (N=7). (Term gestation is E19.5.) Maternal blood, spleen, uterine implantation sites, and placentae were collected, processed, and analyzed for immune cells by flow cytometry (CD45, Ly6G, CD11c, CD11b, CD103, F4/80, IA/IE, CD3, CD4, CD8, CD19, CD49b, TCR γ/δ, FoxP3, IL-17). At E19, term gestation, the frequencies of multiple immune cell types decrease in the placenta: regulatory T cells (1.6 to 0.8%; p=0.0004), NK cells (2.6 to 1.5%; p=0.009), CD11c+ myeloid cells (8.6 to 5.5%; p=0.013), and CD103+ dendritic cells (0.43 to 0.25%; p=0.013). Only NK cells decrease near term in the uterus (9.5 to 1.6%; p=0.011). In contrast, during inflammation-induced preterm birth, macrophages decrease in the placenta (4.4 to 2.5%; p=0.042) and neutrophils increase in the uterus (26 to 52%; p=0.0006). These findings demonstrate that the immune composition of the fetomaternal interface shifts prior to birth. However, both the cell types and location of this shift differ between term and preterm birth, suggesting distinct immunologic mechanisms contribute to these processes.

Pregnancy-associated diamine oxidase originates from extravillous trophoblasts and is decreased in early-onset preeclampsia

Human extravillous trophoblast (EVT) invasion of the pregnant uterus constitutes a pivotal event for the establishment of the maternal-fetal interface. Compromised EVT function manifesting in inadequate arterial remodeling is associated with the severe pregnancy disorder early-onset preeclampsia (eoPE). Recent studies suggest that EVTs invade the entire uterine vasculature including arteries, veins and lymphatics in the first trimester of pregnancy. We therefore hypothesized that EVT-derived factors accumulate in the circulation of pregnant women early in gestation and may serve to predict eoPE. In contrast to published literature, we demonstrate that placenta-associated diamine oxidase (DAO) is not expressed by maternal decidual cells but solely by EVTs, especially when in close proximity to decidual vessels. Cultures of primary EVTs express and secret large amounts of bioactive DAO. ELISA measurements indicate a pregnancy-specific rise in maternal DAO plasma levels around gestational week (GW) 7 coinciding with vascular invasion of EVTs. Strikingly, DAO levels from eoPE cases were significantly lower (40%) compared to controls in the first trimester of pregnancy but revealed no difference at mid gestation. Furthermore, DAO-containing pregnancy plasma rapidly inactivates pathophysiologically relevant histamine levels. This study represents the first proof of concept suggesting EVT-specific signatures as diagnostic targets for the prediction of eoPE.

Maternal Interleukin-6 concentration during pregnancy is associated with variation in frontolimbic white matter and cognitive development in early life

Maternal inflammation during pregnancy can alter the trajectory of fetal brain development and increase risk for offspring psychiatric disorders. However, the majority of relevant research to date has been conducted in animal models. Here, in humans, we focus on the structural connectivity of frontolimbic circuitry as it is both critical for socioemotional and cognitive development, and commonly altered in a range of psychiatric disorders associated with intrauterine inflammation. Specifically, we test the hypothesis that elevated maternal concentration of the proinflammatory cytokine interleukin-6 (IL-6) during pregnancy will be associated with variation in microstructural properties of this circuitry in the neonatal period and across the first year of life.Pregnant mothers were recruited in early pregnancy and maternal blood samples were obtained for assessment of maternal IL-6 concentrations in early (12.6 ± 2.8 weeks [S.D.]), mid (20.4 ± 1.5 weeks [S.D.]) and late (30.3 ± 1.3 weeks [S.D.]) gestation. Offspring brain MRI scans were acquired shortly after birth (N = 86, scan age = 3.7 ± 1.7 weeks [S.D.]) and again at 12-mo age (N = 32, scan age = 54.0 ± 3.1 weeks [S.D.]). Diffusion Tensor Imaging (DTI) was used to characterize fractional anisotropy (FA) along the left and right uncinate fasciculus (UF), representing the main frontolimbic fiber tract. In N = 30 of the infants with serial MRI data at birth and 12-mo age, cognitive and socioemotional developmental status was characterized using the Bayley Scales of Infant Development. All analyses tested for potentially confounding influences of household income, prepregnancy Body-Mass-Index, obstetric risk, smoking during pregnancy, and infant sex, and outcomes at 12-mo age were additionally adjusted for the quality of the postnatal caregiving environment.Maternal IL-6 concentration (averaged across pregnancy) was prospectively and inversely associated with FA (suggestive of reduced integrity under high inflammatory conditions) in the newborn offspring (bi-lateral, p < 0.01) in the central portion of the UF proximal to the amygdala. Furthermore, maternal IL-6 concentration was positively associated with rate of FA increase across the first year of life (bi-lateral, p < 0.05), resulting in a null association between maternal IL-6 and UF FA at 12-mo age. Maternal IL-6 was also inversely associated with offspring cognition at 12-mo age, and this association was mediated by FA growth across the first year of postnatal life.Findings from the current study support the premise that susceptibility for cognitive impairment and potentially psychiatric disorders may be affected in utero, and that maternal inflammation may constitute an intrauterine condition of particular importance in this context.

126 Efficiency of Utilizing Standardized Ileal Digestible Lys for Whole Body Protein Retention in Pregnant Gilts during Early, Mid and Late Gestation.

126 Efficiency of Utilizing Standardized Ileal Digestible Lys for Whole Body Protein Retention in Pregnant Gilts during Early, Mid and Late Gestation.

Immunohistochemical localization of 3β-Hydroxysteroid dehydrogenase and progesterone receptors in the ovary and placenta during gestation of the placentotrophic lizard Mabuya sp (Squamata: Scincidae)

In squamates, progesterone (P) plays a key role in the inhibition of uterine mobility during egg retention in oviparous species, and during gestation in viviparous species. The corpus luteum (CL) is the main organ responsible for the production of P; however, in some species, the CL degenerates early and the P needed for gestation maintenance should be produced in other tissues. Mabuya sp (Scincidae) is a viviparous lizard with a prolonged gestation, it produces microlecithal eggs and, consequently, has an obligate placentotrophy related with a highly complex placenta. Its CL degenerates at early stages of gestation and therefore, other sources of P should exist. The aim of this study was to determine and localize by immunohistochemistry the production of P by detection of the enzyme 3β-Hydroxysteroid dehydrogenase (3β-HSD) and P receptors (PR) during gestation in the ovary and placenta of Mabuya sp. Positive and negative control sections were used. The ovary of this species localizes 3β-HSD and PR in the same tissues. The CL of the ovaries of females at early stages of gestation were positive for both molecules, whereas they did not localize from mid gestation to the end of pregnancy. Previtellogenic and vitellogenic follicles labelled for both molecules in the follicular epithelium and thecae. The placenta of Mabuya sp. demonstrated the potential for P production from mid gestation to the end of gestation in the uterine and chorionic tissues. PR were located in the uterine tissues throughout gestation, with a decrease towards its completion. Western blot analysis confirmed the presence of 3β-HSD mainly in the ovary of early pregnant females and in the placental tissues at mid gestation stages. Therefore, the chorioallantoic placenta of Mabuya sp. has an endocrine function producing the P needed for gestation and replacing the CL from mid gestation to the end of pregnancy.

T cell developmental arrest in former premature infants increases risk of respiratory morbidity later in infancy.

The inverse relationship between gestational age at birth and postviral respiratory morbidity suggests that infants born preterm (PT) may miss a critical developmental window of T cell maturation. Despite a continued increase in younger PT survivors with respiratory complications, we have limited understanding of normal human fetal T cell maturation, how ex utero development in premature infants may interrupt normal T cell development, and whether T cell development has an effect on infant outcomes. In our longitudinal cohort of 157 infants born between 23 and 42 weeks of gestation, we identified differences in T cells present at birth that were dependent on gestational age and differences in postnatal T cell development that predicted respiratory outcome at 1 year of age. We show that naive CD4+ T cells shift from a CD31-TNF-α+ bias in mid gestation to a CD31+IL-8+ predominance by term gestation. Former PT infants discharged with CD31+IL8+CD4+ T cells below a range similar to that of full-term born infants were at an over 3.5-fold higher risk for respiratory complications after NICU discharge. This study is the first to our knowledge to identify a pattern of normal functional T cell development in later gestation and to associate abnormal T cell development with health outcomes in infants.

Assessment of squalene eligibility in bettering some maternal and fetal disorders instigated by gamma irradiation of rats at mid gestation

Purpose: Squalene is an eminent vital part of the synthesis of steroid hormones in the body as well as the first specific intermediate in cholesterol biosynthesis that plays an essential role in normal embryogenesis. The present work was designed to test the maternal and embryonic response to the modulating capacity of squalene (0.4 ml/kg/d), when supplemented to rats from days 1 to 18 of pregnancy, against the damaging consequences induced by maternal subjection to 3 Gy gamma irradiation on day 10 post-conception.Materials and methods: The experimental protocol comprised of four different pregnant groups, namely: (1) control, (2) squalene supplemented, (3) irradiated and (4) squalene supplemented + irradiated.Results: It has been detected that radiation has increased the maternal blood lactate dehydrogenase (as a marker of tissue injury), cholesterol, triglycerides, estradiol and progesterone and has also provoked the oxidative stress that has been demonstrated by the increased malondialdehyde (MDA) and the decreased glutathione (GSH) and superoxide dismutase (SOD). These maternal changes were associated with high embryonic lethality, growth retardation, severe developmental abnormalities and defective neural tube closure expressed by exencephaly. However, squalene treatment has significantly improved the radiation imposed maternal variations and reduced the embryonic mortality, although it has not been able to attenuate the embryonic neural tube defects.Conclusions: It has been presumed that the maternal mid-gestational irradiation (day 10) has affected the fetal nervous system development with concomitant maternal oxidative stress, hyperlipidemia, and increased progesterone and estradiol levels. Squalene uptake has improved the maternal variations and reduced the embryonic mortality while could not stop or improve the embryonic neural tube defects imposed by radiation at this exact radiation timing.

Diet-induced obesity alters the maternal metabolome and early placenta transcriptome and decreases placenta vascularity in the mouse.

Maternal obesity is associated with an increased risk of obesity and metabolic disease in offspring. Increasing evidence suggests that the placenta plays an active role in fetal programming. In this study, we used a mouse model of diet-induced obesity to demonstrate that the abnormal metabolic milieu of maternal obesity sets the stage very early in pregnancy by altering the transcriptome of placenta progenitor cells in the preimplantation (trophectoderm [TE]) and early postimplantation (ectoplacental cone [EPC]) placenta precursors, which is associated with later changes in placenta development and function. Sphingolipid metabolism was markedly altered in the plasma of obese dams very early in pregnancy as was expression of genes related to sphingolipid processing in the early placenta. Upregulation of these pathways inhibits angiogenesis and causes endothelial dysfunction. The expression of many other genes related to angiogenesis and vascular development were disrupted in the TE and EPC. Other key changes in the maternal metabolome in obese dams that are likely to influence placenta and fetal development include a marked decrease in myo and chiro-inositol. These early metabolic and gene expression changes may contribute to phenotypic changes in the placenta, as we found that exposure to a high-fat diet decreased placenta microvessel density at both mid and late gestation. This is the first study to demonstrate that maternal obesity alters the transcriptome at the earliest stages of murine placenta development.

Simultaneous Ablation of Uterine Natural Killer Cells and Uterine Mast Cells in Mice Leads to Poor Vascularization and Abnormal Doppler Measurements That Compromise Fetal Well-being.

Intrauterine growth restriction (IUGR) is a serious pregnancy complication with short- and long-term health consequences. The mechanisms underlying this condition are not well understood. Animal models are the basis for understanding the causes of IUGR and for developing useful therapeutic strategies. Here, we aimed to ascertain the in utero growth of fetuses from NK (natural killer cells)/MC (mast cells)-deficient mothers that give birth to growth-restricted pups and to determine the time point at which IUGR starts. We used high frequency ultrasound imaging to follow-up fetal and placenta size and employed Doppler measurements to document blood supply to the fetus in females that were deficient for NK cells and MCs. In mice lacking NKs and MCs, we observed significantly reduced implantation sizes from mid gestation onward, which was further associated with smaller placentas. Additionally, NK/MC-deficiency was associated with absent and reversed end diastolic flow in umbilical arteries of the fetuses and an increased systolic/diastolic ratio as well as an elevated resistance index. Together, our results indicate that NKs/MCs promote blood flow, placental growth, and subsequent fetal development. The results of this study offer new insights as to how fetal growth is affected in vivo in NK/MC-deficient mice, whose pups are growth restricted at birth. The use of IUGR models and modern technologies enabling the in vivo follow-up of fetal development are important tools for understanding mechanisms behind pregnancy complications that in the future may lead to the development of effective therapies.

Placental osseous metaplasia associated with abortion in a mare: case report

ABSTRACT The aim of this report is to describe a case of marked osseous metaplasia in the placenta associated with abortion in a mare. A 19-year-old Campolina mare with a history of multiple parturitions and absence of reproductive failure, aborted a fetus with approximately six months of gestation. There were no gross changes in the fetus and the placenta. Microscopically, there was multifocal replacement of fetal connective mesenchyme of the chorionic villi with well differentiated and partially mineralized osseous tissue (confirmed by von Kossa staining). To further characterize the collagenous component of the lesion, sections of the placenta were stained with Masson’s trichrome and Picrosirius red. Osseous tissue deposition had abundance of type I collagen. To the best of our knowledge, this is the first report of osseous metaplasia in the placenta of a mare associated with abortion at mid gestation, presumably due to placentary insufficiency.

Prenatal and Postnatal Lamb Muscle Growth as Influenced by Ergot Alkaloid Exposure in Utero

ObjectivesTwo experiments were conducted to determine the impact of ergot alkaloids fed during 2 stages of gestation (MID, d 35 to 85, or LATE, d 86 to 133/parturition) on prenatal (Experiment 1, Exp1) and postnatal (Experiment 2, Exp 2) lamb muscle growth.Materials and MethodsPregnant Suffolk ewes (Expt. 1, n = 36, BW 78.02 ± 9.53 kg; Expt. 2, n = 60, BW 83.13 ± 1.69 kg) were fed endophyte-infected tall fescue seed (E+; 1772 µg/hd/d ergovaline+ergovalinine) or endophyte-free tall fescue seed (E-; 0 µg/hd/d ergovaline+ergovalinine) during MID or LATE gestation, which created 4 dietary treatments of E+/E+, E+/E-, E-/E+, and E-/E. Maternal and fetal necropsies were performed at d 133 of gestation. Semitendinosus (ST) muscle was removed from each fetus, immediately frozen in liquid nitrogen and stored at –80°C. Total cellular RNA was extracted using the mirVana miRNA Isolation Kit (Ambion, Austin, TX) and quality analysis of RNA performed using an Agilent 2100 Bioanalyzer, with a RIN threshold of 7.0. The tcRNA from 3 fetuses per treatment from the ST was used for miRNA sequencing and data analysis (LC Sciences, Houston, TX). Data was analyzed as a randomized block design with a 2 × 2 factorial with fescue treatment (E+ or E-), stage of gestation (MID or LATE), and 2-way interaction in the model. In Expt. 2, Suffolk ewes were stratified by genotype (dopamine receptor 2 [DRD2] SNP; AA, AG, GG) and assigned to fescue treatments of E+ or E- fed during 2 stages of gestation, MID or LATE similar to Expt. 1, except that ewes were allowed to lamb naturally. Data for Expt. 2 were analyzed as a 3 × 2 × 2 factorial with ewe genotype, fescue treatment, time of gestation and all interactions in the model. Lamb weights were recorded at birth and weaning. At weaning, wethers (n = 44) were fed individually a high concentrate diet until they reached 59 kg or 185 d postweaning.ResultsPrenatal (d 133) lamb fetal weights were lower (P < 0.05) for ewes fed E+ fescue during LATE gestation (E-/E+ and E+/E+). Total and individual muscle mass were also lower in fetal lambs from ewes fed E+ fescue during LATE gestation. miRNA transcriptome were altered in the semitendinosus muscle of fetal lambs from ewes fed E+ fescue during LATE gestation. Exp. 2 lamb birth and weaning weight was lower (P < 0.05) for ewes fed E+ tall fescue seed during LATE gestation. At slaughter, wethers from GG ewes fed E+ had greater live weight than E-. Hot carcass weights, dressing percentage, and carcass traits did not differ due to fescue treatment. Biceps femoris muscle was lower on a percentage of hot carcass weight for wethers from ewes fed E+ fescue during LATE gestation. Carcass fat percentage, as measured by dual-energy X-ray absorptiometry at 24 h postmortem, did not differ (P > 0.05) by ewe genotype or fescue treatment.ConclusionExposure to ergot alkaloids from E+ fescue during LATE gestation reduces prenatal and postnatal muscle growth in lambs, and alters prenatal muscle miRNA expression.

Effects of maternal nutrient restriction during early or mid-gestation without realimentation on maternal physiology and foetal growth and development in beef cattle

The aim of this study is to determine the effects of early and mid-gestation nutrient restriction on maternal metabolites and foetal growth. Primiparous Angus cows were synchronized and inseminated with semen from one sire. Dietary treatments were: control to gain 1 kg/week (CON) or 0.55% maintenance energy and CP requirements (nutrient restricted; NR). A subset of dams was fed NR (n=8) or CON (n=8) from days 30 to 110 of gestation. Another group was fed CON (n=8), days 30 to 190; NR (n=7), days 30 to 110 followed by CON days 110 to 190; or CON, (n=7) days 30 to 110 followed by NR days 110 to 190. Cows were harvested at days 110 or 190 of gestation, when foetal measurements and samples were collected. Cows that were NR during days 30 to 110 or 110 to 190 of gestation lost significant BW and body condition score (P<0.001), this was associated with reduced plasma glucose during NR (P<0.002). Foetal weights, empty foetal weights, abdominal and thoracic circumferences were all reduced (P<0.03) in day 110 NR animals. Foetal perirenal adipose as a percentage of empty foetal weight was increased (P=0.01) in NR day 110 female foetuses compared with CON foetus. Maternal serum triglycerides at day 110 of gestation were decreased (P<0.05) in NR dams, whereas foetal serum triglycerides were increased (P<0.05) in response to maternal NR. Foetal weights tended to be reduced (P=0.08) in NR/CON and CON/NR v. CON/CON cattle at day 190 of gestation. Empty foetal weights, abdominal and thoracic circumferences were reduced (P⩽0.03) in NR/CON and CON/NR v. CON/CON cattle. Brain weight as a percentage of empty foetal weight was increased (P<0.001) in NR/CON and CON/NR v. CON/CON cattle. Foetal perirenal adipose as a percentage of empty foetal weight was increased (P=0.003) in NR/CON and CON/NR v. CON/CON cattle. Maternal serum triglycerides at day 190 of gestation were decreased (P<0.05) in association with maternal NR. Foetal serum triglycerides at day 190 of gestation were increased (P<0.05) in response to maternal NR during early gestation but decreased by NR in mid gestation compared with CON foetuses. The data show that maternal nutrient restriction during early or mid-gestation cause’s asymmetrical foetal growth restriction, regardless if the restriction is preceded or followed by a period of non-restriction.