The Effects of Maternal Nutrient Restriction during Mid to Late Gestation with Realimentation on Fetal Metabolic Profiles in the Liver, Skeletal Muscle, and Blood in Sheep.

Poor maternal nutrition during gestation negatively affects offspring growth and metabolism. To evaluate the impact of maternal nutrient restriction and realimentation on metabolism in the fetal liver, skeletal muscle, and circulation, on day 50 of gestation, ewes ( = 48) pregnant with singletons were fed 100% (CON) or 60% (RES) of requirements until day 90 of gestation, when a subset of ewes ( = 7/treatment) were euthanized, and fetal samples were collected. The remaining ewes were maintained on a current diet (CON-CON, = 6; RES-RES, = 7) or switched to an alternative diet (CON-RES, RES-CON; = 7/treatment).

The effects of follicle stimulating hormone (FSH)-induced controlled ovarian hyperstimulation and nutrition on implantation-related gene expression in caruncular tissues of non-pregnant sheep.

Disturbances at the conceptus-maternal interface can have detrimental effects on pregnancy outcome. Additionally, changes in body condition and exogenously administered gonadotropins could affect ovarian and uterine function, including cell proliferation and ovulation rates, and alter endometrial receptivity. In ruminants, endometrial caruncles maintain placental function via interaction with fetal chorionic cotyledons.

Plane of nutrition and FSH-induced superovulation affect the expression of steroid hormone receptors and growth factors in caruncular tissue of non-pregnant sheep.

Implantation is a critical step in the establishment of pregnancy and an important part of embryo-maternal contact. Uterine receptivity can be affected by changes in body condition and the maternal endocrine milieu, including those caused by the use of exogenous gonadotropins in controlled ovarian hyperstimulation to induce the development of multiple follicles. This study demonstrates the effects of FSH-mediated ovarian hyperstimulation on the caruncles of ewes under various feeding regimes.

Mid- to late-gestational maternal nutrient restriction followed by realimentation alters development and lipid composition of liver and skeletal muscles in ovine fetuses.

Maternal nutrient restriction during gestation adversely affects offspring growth and development of liver and skeletal muscle tissues. Realimentation following nutrient restriction may alleviate these negative impacts on development but may alter metabolism and tissue composition. Forty-eight ewes, pregnant with singletons, were fed to meet 100% National Research Council (NRC) recommendations starting at the beginning of gestation.

Maternal periconceptual nutrition, early pregnancy, and developmental outcomes in beef cattle.

The focus of this review is maternal nutrition during the periconceptual period and offspring developmental outcomes in beef cattle, with an emphasis on the first 50 d of gestation, which represents the embryonic period. Animal agriculture in general, and specifically the beef cattle industry, currently faces immense challenges. The world needs to significantly increase its output of animal food products by 2050 and beyond to meet the food security and agricultural sustainability needs of the rapidly growing human population.

Nuclear and membrane progesterone receptors expression in placenta from early to late pregnancy in sheep: Effects of restricted nutrition and realimentation.

Nutrient restriction and/or realimentation may affect several placental functions, such as expression of selected regulatory factors, blood flow and other processes in sheep and other species. To determine the effects of the plane of nutrition, nulliparous white face ewes (6-8 months) carrying singletons on day 50 of gestation were randomly assigned to two dietary treatments receiving 100% of National Research Council recommendations (control; C) or 60% of C (restricted; R). Two groups remained on C or R diets from day 50 until day 130.

Lipopolysaccharide disrupts gap junctional intercellular communication in an immortalized ovine luteal endothelial cell line.

Gram-negative bacteria, in particular Escherichia coli with its cell wall lipopolysaccharide (LPS), often cause metritis and mastitis in domestic animals. Ovarian LPS accumulation may initiate local inflammatory reactions mediated through cell surface Toll-like receptors (TLRs). This may disrupt ovarian functionality leading to infertility.

Effects of plane of nutrition and arginine on ovarian follicles in non-pregnant sheep: Cell proliferation, and expression of endothelial nitric oxide and its receptor.

The aim of this study was to investigate the role of the nitric oxide (NO) system in ovarian function, by determining if arginine (Arg) supplementation impacts follicle number, cell proliferation, and expression of the NO system members in nutritionally compromised ewes. Ewes were randomly assigned into maintenance (C, 100% requirements), excess (O; 2xC), or restricted (U; 0.6xC) diets 8 weeks prior to Arg treatment.

Placental development during early pregnancy in sheep: nuclear estrogen and progesterone receptor mRNA expression in the utero-placental compartments.

Sex steroid hormones are major regulators of uterine and placental growth and functions, as well as many other biological processes. To examine the mRNA expression of nuclear estrogen (ESR1 and 2) and progesterone (PGRAB and B) receptors in different compartments of the uterus and placenta, tissues were collected in experiment 1 on days 16, 20, and 28 after natural mating (NAT) and on day 10 after estrus (nonpregnant controls [NP]); and in experiment 2 on day 22 of NAT, and pregnancies established after transfer of embryos generated through mating of FSH-treated ewes (NAT-ET), in vitro fertilization (IVF), or in vitro activation (parthenotes). In experiment 1, ESR1 expression in endometrial stroma (ES), endometrial glands (EGs), and myometrial blood vessels (MBVs), ESR2 in endometrial blood vessels (EBV), PGRAB in ES, and PGRB in ES, EG, and MBV was greater in pregnant than NP ewes depending on the day of pregnancy.

Angiopoietin expression in ovine corpora lutea during the luteal phase: Effects of nutrition, arginine and follicle stimulating hormone.

The aim of this study was to evaluate angiopoietin (ANGPT) 1 and 2, and tyrosine-protein kinase receptor 2 (TIE2) expression in the corpora lutea (CL) of FSH-treated, or non-treated sheep administered arginine (Arg) or vehicle (saline, Sal), and fed a control (C), excess (O) or restricted (U) diet. Ewes from each dietary group were treated with Arg or Sal (experiment 1), and with FSH (experiment 2). Luteal tissues were collected at the early-, mid- and/or late-luteal phases of the estrous cycle.

Luteal ANGPT-TIE system during selected stages of pregnancy, and normal and antigestagen-induced luteolysis in the dog.

Rapid establishment of a vascular network is essential for normal functionality of the corpus luteum (CL). The early luteal phase is associated with increased expression of the VEGF system in canine CL. Acting in synchrony with angiopoietins (ANGPTs), VEGF system plays major roles in stabilization of blood vessels.

Follicle stimulating hormone receptor protein is expressed in ovine uterus during the estrous cycle and utero-placenta during early pregnancy: An immunohistochemical study.

Follicle stimulating hormone (FSH) is a well characterized gonadotropin that controls primarily development and functions of ovarian follicles in mammalian species. FSH binds to a specific G protein-coupled receptor (FSHR) belonging to the glycoprotein hormone receptor family that plays an essential role in reproduction. Although the primary location of FSHR is in the gonads (mainly in ovarian follicles), FSHR protein and/or mRNA have also been detected in extragonadal female reproductive tissues including embryo, placenta, endometrium, cervix, ovarian cancer tissues, and/or endometriotic lesions in several species.

Placental development during early pregnancy in sheep: Progesterone and estrogen receptor protein expression.

The aim of this study was to evaluate the pattern of protein expression of the steroid receptor isoforms of nuclear progesterone receptors (PGR) A and B, and estrogen receptors (ESR1 and 2) in utero-placental compartments during early pregnancy. Utero-placental tissues were collected from days 14-30 (n = 4 ewes/day), and uterine tissues were collected from non-pregnant ewes on day 10 after estrus (n = 4). Cross sections of formalin-fixed and paraffin embedded tissues were immunofluorescently stained to detect PGRAB, PGRB, ESR1 and ESR2, followed by image generation of entire cross-sections of uterine and utero-placental tissues, confocal imaging of individual uterine and utero-placental compartments, and image and statistical analyses.

Expression of progesterone receptor protein in the ovine uterus during the estrous cycle: Effects of nutrition, arginine and FSH.

To evaluate expression of progesterone receptor (PGR) AB in follicle stimulating hormone (FSH)-treated or non-treated sheep administered with arginine (Arg) or saline (Sal) fed a control (C), excess (O) or restricted (U) diet, uterine tissues were collected at the early, mid and/or late luteal phases. In exp. 1, ewes from each diet were randomly assigned to one of two treatments, Arg or Sal administration three times daily from day 0 of the first estrous cycle until uterine tissue collection.

A Preliminary Evaluation of Ovine Bladder Mucosal Damage Associated With 2 Different Indwelling Urinary Catheters.

Objective: To determine whether a new catheter design with a low-profile, open-ended rounded rather than pointed Foley catheter tip can reduce mucosal damage to the bladder of ewes.

Methods And Materials: Six ewes were randomly assigned to 1 of 2 indwelling urinary catheters-a 16 Fr Foley catheter or a 16 Fr open-tip CystoSure catheter. After 96 hours, all the animals were sacrificed and their bladder and urethra harvested for analysis.

Luteal function during the estrous cycle in arginine-treated ewes fed different planes of nutrition.

Functions of corpus luteum (CL) are influenced by numerous factors including hormones, growth and angiogenic factors, nutritional plane and dietary supplements such as arginine (Arg), a semi-essential amino acid and precursor for proteins, polyamines and nitric oxide (NO). The aim of this study was to determine if Arg supplementation to ewes fed different planes of nutrition influences: (1) progesterone (P4) concentrations in serum and luteal tissue, (2) luteal vascularity, cell proliferation, endothelial NO synthase (eNOS) and receptor (R) soluble guanylate cyclase β protein and mRNA expression and (3) luteal mRNA expression for selected angiogenic factors during the estrous cycle. Ewes (n = 111) were categorized by weight and randomly assigned to one of three nutritional planes: maintenance control (C), overfed (2× C) and underfed (0.

Lipid droplets in the ovine uterus during the estrous cycle: Effects of nutrition, arginine, and FSH.

The aim of this study was to evaluate lipid droplet (LD) expression in uteri of FSH-treated or nontreated sheep administered with arginine (Arg) or vehicle (saline, Sal) and fed a control (C), excess (overfed, O) or restricted (underfed, U) diet. In experiment 1, ewes from each diet were randomly assigned to Arg or Sal treatments administered three times daily starting on Day 0 of the first estrous cycle until blood sample and uterine tissue collection at the early- or mid-luteal phase of the second estrous cycle or the late-luteal phase of the first estrous cycle. In experiment 2, ewes were injected twice daily with FSH on Days 13 to 15 of the first estrous cycle, and blood samples and uterine tissue were collected at the early- and mid-luteal phases of the second estrous cycle.

Lipid droplets in cultured luteal cells in non-pregnant sheep fed different planes of nutrition.

Accumulation of lipid droplets (LD) in luteal cells likely is important for energy storage and steroidogenesis in the highly metabolically active corpus luteum (CL). The objective of this study was to determine the effect of plane of nutrition on progesterone (P4) secretion, and lipid droplet number and size in cultured ovine luteal cells. Ewes were randomly assigned to one of three nutritional groups: control (C; 100% NRC requirements, n=9), overfed (O; 2×C, n=12), or underfed (U; 0.

Progesterone secretion by ovine granulosa cells: effects of nitric oxide and plane of nutrition.

The aim was to evaluate the effects of nutritional plane on in vitro progesterone (P4) secretion by granulosa (G) cells cultured in the presence or absence of effectors of the nitric oxide (NO) system. Ewes were randomly assigned into three nutritional groups: control (C), overfed (O; 2 × C), or underfed (U; 0.6 × C).

The effects of diet and arginine treatment on serum metabolites and selected hormones during the estrous cycle in sheep.

The aim of this study was to determine the effects of diet and arginine (Arg) treatment on serum concentrations of selected metabolites and metabolic and reproductive hormones in nonpregnant ewes. Sixty days before the onset of estrus (Day 0), Rambouillet ewes were randomly assigned to one of three dietary groups: maintenance control (C; N = 16; 100% National Research Council requirements), overfed (O; N = 16; 2 × C), or underfed (U; N = 16, 0.6 × C) to achieve and maintain three different body conditions during their estrous cycle(s).

Placental vascular defects in compromised pregnancies: effects of assisted reproductive technologies and other maternal stressors.

Many factors negatively affect pregnancy establishment and subsequent fetal growth and development, including maternal factors such as nutritional stress, age, body mass index, and genetic background, and external factors including environmental stress, psychosocial stress, multiple fetuses, medical conditions (e.g., polycystic ovary syndrome), lifestyle choices (e.

Prion (PrPC) expression in ovine uteroplacental tissues increases after estrogen treatment of ovariectomized ewes and during early pregnancy.

Scrapie in sheep is spread laterally by placental transmission of an infectious misfolded form (PrPSc) of a normal prion protein (PrPC) used as a template in PrPSc formation. We hypothesized that PrPC would be expressed in uterine and placental tissues and estradiol-17β (E2) would affect uterine PrPC expression. PrPC expression was evaluated in the uterus of long-term ovariectomized (OVX) ewes treated with an E2 implant for 2-24 h and in uteroplacental tissues from day 20 to day 30 of pregnancy.

Ovarian and uterine characteristics and onset of puberty in adolescent offspring: effects of maternal diet and selenium supplementation in sheep.

The aim of this study was to determine the effects of maternal diet with adequate (A) or high (H) selenium (Se) supplementation on ovarian and uterine characteristics, and onset of puberty in adolescent offspring. Sheep were fed a maintenance (M) diet with ASe or HSe levels from breeding to parturition. From Day 50 to parturition, a portion of the ewes from ASe and HSe groups was fed restricted (R, 60% of M) or excess (E, 140% of M) diet.

Placental development during early pregnancy in sheep: effects of embryo origin on vascularization.

Utero-placental growth and vascular development are critical for pregnancy establishment that may be altered by various factors including assisted reproductive technologies (ART), nutrition, or others, leading to compromised pregnancy. We hypothesized that placental vascularization and expression of angiogenic factors are altered early in pregnancies after transfer of embryos created using selected ART methods. Pregnancies were achieved through natural mating (NAT), or transfer of embryos from NAT (NAT-ET), or IVF or in vitro activation (IVA).

Maternal stress and placental vascular function and remodeling.

This review discusses the importance of placental vascular development, as reflected by placental angiogenesis and placental blood flow, to placental function in normal pregnancies. We then summarize our current understanding of how maternal stress, including inadequate maternal nutrition as well as the application of assisted reproductive technologies (ART), leads to compromised placental angiogenesis and function and the subsequent effects on fetal and neonatal growth and development. Finally, we discuss several promising therapeutic approaches to 'rescue' placental vascular development and function in compromised pregnancies, leading to improved pregnancy and postnatal outcomes.