Mapping the lipidomic secretome of the early equine embryo.

The lipidomic secretions of embryos provide a unique opportunity to examine the cellular processes of the early conceptus. In this study we profiled lipids released by the early equine conceptus, using high-resolution mass spectrometry to detect individual lipid species. This study examined the lipidomic profile in embryo-conditioned media from -produced, 8-9 day-old equine embryos ( = 3) cultured for 36 h, analyzed over 3 timepoints.

Investigations into the role of platelet-activating factor in the peri-conception period of the mare.

In Brief: In many mammals, the lipid platelet-activating factor (PAF) has important functions in female reproduction and fertility. This study shows that PAF is present in the reproductive tissues of mares and is involved in processes related to ovulation and early pregnancy.

Abstract: Platelet-activating factor (PAF) has been implicated in a number of reproductive processes ranging from ovulation to embryo motility but has not been widely explored in the mare.

Effect of probiotics and prebiotics on the composition of the equine fecal and seminal microbiomes and sperm quality: A pilot study.

Probiotic and prebiotic effects on equine semen and gastrointestinal microbiome composition and sperm quality are unknown. This study aimed to evaluate the effects of pre-, pro- or synbiotic supplementation on fecal and semen microbiome composition and sperm quality parameters of stallions. This Latin square crossover trial involved four miniature pony stallions receiving control diet only, or addition of a pro-, pre- or synbiotic formulation.

The semen microbiome of miniature pony stallions.

Context: Little is known about the microbial composition of stallion semen.

Aims: To describe the microbiota detected in equine semen of healthy miniature pony stallions.

Methods: Semen specimens were collected using a Missouri artificial vagina at a single time point.

Cloned Foal Born from Postmortem-Obtained Ear Sample Refrigerated for 5 Days Before Fibroblast Isolation and Decontamination of the Infected Monolayer Culture.

A 6-year-old mare, a valuable polo horse, died of complications following postcolic surgery. To preserve its genetics, ear skin samples were collected immediately after death and stored in an equine embryo transfer medium at 4°C for 5 days. After trypsin digestion, monolayer fibroblast cultures were established, but signs of massive bacterial infection were found in all of them.

Vaginal and vestibular electrical resistance as an alternative marker for optimum timing of artificial insemination with liquid-stored and frozen-thawed spermatozoa in sows.

Development of a pen-side test to objectively determine the ideal time for artificial insemination (AI) in the sow would save producers time and money. Current processes rely on identification of oestrus via subjective behavioural and physiological markers that are indicative of high blood oestrogen concentrations. This study attempted to use measurements of electrical resistance (ER) in the cervical mucus to pinpoint timing of AI accurately enough to lead to equivalent pregnancy rates as a natural mating.

Cloning horses by somatic cell nuclear transfer: Effects of oocyte source on development to foaling.

The cloning of horses is a commercial reality, yet the availability of oocytes for cloned embryo production remains a major limitation. Immature oocytes collected from abattoir-sourced ovaries or from live mares by ovum pick-up (OPU) have both been used to generate cloned foals. However, the reported cloning efficiencies are difficult to compare due to the different somatic cell nuclear transfer (SCNT) techniques and conditions used.

Establishment and characterization of oviductal organoids from farm and companion animals†.

Organoid technology has provided a unique opportunity to study early human development and decipher various steps involved in the pathogenesis of disease. The technology is already used in clinics to improve human patient outcomes. However, limited knowledge of the methodologies required to establish organoid culture systems in domestic animals has slowed the advancement and application of organoid technology in veterinary medicine.

NAD, Sirtuins and PARPs: enhancing oocyte developmental competence.

Oocyte quality is the limiting factor in female fertility. It is well known that maternal nutrition plays a role in reproductive function, and manipulating nutrition to improve fertility in livestock has been common practice in the past, particularly with respect to negative energy balance in cattle. A deficiency in nicotinamide adenine dinucleotide (NAD) production has been associated with increased incidences of miscarriage and congenital defects in humans and mice, while elevating NAD through dietary supplements in aged subjects improved oocyte quality and embryo development.

Supplemental Nicotinic Acid Elevates NAD Precursors in the Follicular Fluid of Mares.

A deficiency in NAD has previously been linked with increased occurrences of congenital abnormalities and embryonic death in humans and mice. Early embryonic death is a major factor involved in pregnancy loss in mares, and very little is known regarding the NAD requirements for optimum reproductive function in horses. The aim of this study was to determine the effect of supplementing the diet of mares with nicotinic acid (NA) on the composition of NAD metabolites in the blood and follicular fluid.

Conception and early pregnancy in the mare: lipidomics the unexplored frontier.

Unlabelled: Lipids are dynamic biological molecules that play key roles in metabolism, inflammation, cell signalling and structure. They are biologically significant in the physiology of conception and reproduction. Many of the mechanisms surrounding equine conception and the early feto-maternal dialogue are yet to be understood at a biochemical level.

Insights into the NAD biosynthesis pathways involved during meiotic maturation and spindle formation in porcine oocytes.

Treatments that elevate NAD levels have been found to improve oocyte quality in mice, cattle, and pigs, suggesting that NAD is vital during oocyte maturation. This study aimed to examine the influence of different NAD biosynthetic pathways on oocyte quality by inhibiting key enzymes. Porcine oocytes from small antral follicles were matured for 44 h in a defined maturation system supplemented with 2-hydroxynicotinic acid [2-HNA, nicotinic acid phosphoribosyltransferase (NAPRT) inhibitor], FK866 [nicotinamide phosphoribosyltransferase (NAMPT) inhibitor], or gallotannin [nicotinamide mononucleotide adenylyltransferase (NMNAT) inhibitor] and their respective NAD pathway modulators (nicotinic acid, nicotinamide, and nicotinamide mononucleotide, respectively).

Supplementing media with NAD precursors enhances the in vitro maturation of porcine oocytes.

In vitro maturation (IVM) is an important reproductive technology used to produce embryos in vitro. However, the developmental potential of oocytes sourced for IVM is markedly lower than those matured in vivo. Previously, NAD-elevating treatments have improved oocyte quality and embryo development in cattle and mice, suggesting that NAD is important during oocyte maturation.

Nicotinic acid supplementation at a supraphysiological dose increases the bioavailability of NAD precursors in mares.

NAD deficiency has recently been linked with increased occurrences of congenital abnormalities and embryonic death in human and animal subjects. Early embryonic death is a major component of pregnancy loss in mares and very little is known regarding the requirement for NAD in horses. The aim of this study was to quantify NAD and its metabolites in the plasma and urine of mares after orally administering an acute dose of nicotinic acid and determine the absorption, metabolism and excretion of this essential precursor for NAD biosynthesis.

Serum Concentrations of AMH and E2 and Ovarian and Uterine Traits in Gilts.

Poor sow retention due to reproductive failure is a common reproductive inefficiency amongst piggeries. This shows that traditional methods of gilt selection are inadequate and a marker of reproductive success is needed. The aim of this study was to determine whether circulating levels of AMH and E2 at D80 and D160 are associated with uterine and ovarian traits at D160.

Effect of carbohydrates on lipid metabolism during porcine oocyte IVM.

Porcine oocytes contain a large amount of endogenous lipid, which is thought to function as an intracellular source of energy. The aim of this study was to determine the effects of stimulating or inhibiting lipid metabolism using l-carnitine or etomoxir respectively on the IVM of porcine oocytes cultured in media of varying carbohydrate composition. In the presence of pyruvate and lactate, exclusion of glucose inhibited oocyte nuclear and cytoplasmic maturation compared with oocytes matured in media containing low (1.

pH: the silent variable significantly impacting meiotic spindle assembly in mouse oocytes.

Research Question: Temperature fluctuation negatively impacts the assembly and function of the meiotic spindle, but does pH have a similar effect?

Design: Polarized light microscopy was used to study the spindle in living mouse oocytes under different pH conditions. Female mice (n = 53) were superovulated, and oocytes collected, denuded and allocated to treatment groups. All experiments were performed at 37°C, and standard bicarbonate-buffered medium was used either pre-equilibrated in 6% CO or unequilibrated (in ambient CO).

Effect of different penetrating and non-penetrating cryoprotectants and media temperature on the cryosurvival of vitrified in vitro produced porcine blastocysts.

The aim of this study was to determine the most efficient vitrification protocol for the cryopreservation of day 7 in vitro produced (IVP) porcine blastocysts. The post-warm survival rate of blastocysts vitrified in control (17% dimethyl sulfoxide + 17% ethylene glycol [EG] + 0.4 mol/L sucrose) and commercial media did not differ, nor did the post-warm survival rate of blastocysts vitrified in medium containing 1,2-propandiol in place of EG.

Anti-Müllerian hormone and Oestradiol as markers of future reproductive success in juvenile gilts.

There is a need for an early marker for reproductive success in gilts as the traditional process for selecting breeding females is inefficient. There is evidence that circulating anti-Müllerian hormone (AMH) is indicative of ovarian reserve, antral follicle populations, gonadotropin responsiveness and fertility in various species other than the pig. Additionally, oestradiol (E2) has been shown to mark antral follicle populations in cattle and pregnancy outcomes in women, after gonadotropin treatment.

Vitrification, not cryoprotectant exposure, alters the expression of developmentally important genes in in vitro produced porcine blastocysts.

The vitrification of embryos is common practice in advanced livestock breeding programs and in human fertility clinics. Recent studies have revealed that vitrification results in aberrant expression of a number of stress related genes. However, few studies have examined the effect that vitrification has on developmentally important genes, and none have been conducted in porcine embryos.

From Peptide Masses to Pregnancy Maintenance: A Comprehensive Proteomic Analysis of The Early Equine Embryo Secretome, Blastocoel Fluid, and Capsule.

Early pregnancy in the mare is a poorly understood, high risk period during which the embryo communicates its presence to the maternal endometrium. Remarkably, the maternal recognition of pregnancy signal is unknown in the horse. This study aimed to profile the proteins secreted by equine blastocysts into their immediate environment, along with proteins contained in the blastocoel and within the acellular embryo capsule.

Cryotolerance of porcine blastocysts is improved by treating in vitro matured oocytes with L-carnitine prior to fertilization.

Sufficient generation of adenosine triphosphate (ATP) by oocytes is critical for fertilization and embryo development. The objective of this study was to determine the effects of supplementing media with L-carnitine, a co-factor required for the metabolism of fatty acids, during the peri-fertilization period on embryo development and energy generation. Firstly, in vitro matured (IVM) porcine oocytes were co-incubated with sperm in IVF medium supplemented with 0‒24 mM L-carnitine.

A comparison of different vitrification devices and the effect of blastocoele collapse on the cryosurvival of in vitro produced porcine embryos.

The aim of this study was to determine the optimum conditions for vitrifying in vitro produced day 7 porcine embryos using different vitrification devices and blastocoele collapse methods. Firstly embryos were collapsed by micro-pipetting, needle puncture and sucrose with and without conducting vitrification. In the next experiment, non-collapsed embryos were vitrified in an open device using either superfine open-pulled straws (SOPS) or the CryoLoop(TM) system, or vitrified in a closed device using either the CryoTip(TM) or Cryo Bio(TM)'s high security vitrification system (HSV).

Characterization of an L-amino acid oxidase in equine spermatozoa.

This study demonstrates for the first time the presence of an L-amino acid oxidase (LAAO) enzyme in equine spermatozoa that is able to generate significant amounts of reactive oxygen species (ROS) and create a state of oxidative stress. RT-PCR analysis revealed that the mRNA for this enzyme was present in the equine testis and spermatozoa, while immunocytochemical studies demonstrated that the mature LAAO protein was located in the sperm head, particularly in the acrosomal and postacrosomal domains. Experimental studies demonstrated that the aromatic amino acids (L-phenylalanine > L-tryptophan > L-tyrosine) were substrates for this enzyme, eliciting the dose- and time-dependent generation of ROS via mechanisms that were enhanced by cell death.

Reproductive physiology and ovarian folliculogenesis examined via 1H-NMR metabolomics signatures: a comparative study of large and small follicles in three mammalian species (Bos taurus, Sus scrofa domesticus and Equus ferus caballus).

The aim of this study was to characterize the composition of follicular fluid (FF) collected from the small and large follicles of three mammalian species, Bos taurus, Sus scrofa domesticus, and Equus ferus caballus, that display distinct ovulatory properties. For each species, five large FF samples and five small FF samples were analyzed using 1H-NMR spectroscopy. The FF metabolic profiles of the three species were very distinct.