Journal of Equine Veterinary Science This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Blastocyst Rates and Kinetics of Sperm Processing After Conventional vs. Piezo-driven ICSI
Equine intracytoplasmic sperm injection (ICSI) is conducted using two main techniques, conventional (Conv) and Piezo-driven (Piezo). Piezo ICSI has been associated with repeatable high (> 25%) equine blastocyst rates per injected oocyte in several laboratories, whereas Conv has been associated with variable and, in general, lower blastocyst rates. Little information is available on direct comparison of the two methods. Because Piezo ICSI entails added equipment expense, requirement for expertise, and typically the use of mercury, use of Conv ICSI would simplify application of ICSI as an equine assisted reproductive techniq...
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: R.M. Salgado, J.G. Brom-de-Luna, H.L. Resende, H.S. Canesin, K. Hinrichs Source Type: research

Production and Sex Ratio of Foals After Transfer of Frozen-thawed In Vitro Produced Embryos
In vitro embryo production via intracytoplasmic sperm injection (ICSI) offers a possible solution for donor mares or stallions not suitable for conventional embryo transfer (ET), and embryo yield (1 per OPU) compares favourably to ET. However, the final outcome after transferring frozen-thawed in vitro-produced (IVP) embryos is not well described. The aim of this study was to determine the pregnancy and foaling outcomes after transfer of frozen-thawed IVP equine embryos in a clinical program, using fresh in vivo-recovered embryos as a reference point, and to examine the influence of rate of in vitro embryo development (tim...
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: A. Claes, J. Cuervo-Arango, S. Colleoni, G. Lazzari, C. Galli, T.A. Stout Source Type: research

Compromised Spindle Assembly Check-point Function in Oocytes From Aged Mares Impairs Correct Chromosome Alignment
This study evaluated the effect of advanced maternal age on spindle assembly check-point (SAC) component expression and function in mares. Cumulus oocyte complexes from slaughtered mares were grouped by mare age (young, (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: M. Rizzo, G.J.P.L. Kops, C. Deelen, M. Beitsma, S. Cristarella, T.A.E. Stout, M. de Ruijter-Villani Source Type: research

Vitrifying Equine Oocytes at the Germinal Vesicle Stage Disturbs Spindle Morphology and Chromosome Alignment
Cryopreserving horse oocytes compromises the ability of immature oocytes to complete meiosis, and reduces the post-fertilization developmental competence of mature oocytes. Previous studies suggest that this reduced competence is, at least in part, related to a compromised ability to form a normal microtubular spindle and complete the meiotic divisions. To better understand the effects of cryopreservation on microtubule spindle function, we examined the effects of vitrifying germinal vesicle stage oocytes on meiotic spindle organization and chromosome alignment after maturation in vitro. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: K.D. Ducheyne, M. Rizzo, M. Beitsma, C. Deelen, P.F. Daels, T.A.E. Stout, M. de Ruijter-Villani Source Type: research

Factors That Modify the Risk of Early Pregnancy Loss and Early Conceptus Growth in Thoroughbreds
The objective of this study was to identify mare, pregnancy and therapeutic factors that modify (i) risk of EPL and (ii) early conceptus growth. A prospective cohort investigation of Thoroughbred broodmares in the United Kingdom was conducted over the 2013 and 2014 breeding seasons. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: B.V. Rose, Y.M. Chang, D.C. Wathes, K.L.P. Verheyen, A.M. de Mestre Source Type: research

MHC Social Signaling Affects Reproductive Strategies of Stallions and Mares
The major histocompatibility complex (MHC) plays an important role in the immune system of vertebrates and has repeatedly been found to influence social signaling in the context of mate preferences, cryptic female choice, and kin recognition. Evidence for MHC social signaling has been reported in more than 20 vertebrate species so far, including man. In the context of mate preferences, MHC-dissimilar mating partners tend to be preferred over MHC-similar ones, either to avoid inbreeding or to increase heterozygosity among the offspring. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: D. Burger, E. Marti, E. Jeannerat, R. Kaeser, H. Sieme, C. Wedekind Source Type: research

The effect of Glucose Concentration (5.6 mM vs. 17 mM) During IVM on Developmental and Metabolic Markers of Equine Cumulus-oocyte Complex Function
Both M199 and DMEM/F-12 support in vitro maturation (IVM) of equine oocytes and production of viable embryos after ICSI. However, these media differ markedly in glucose concentration: 5.6 mM (M199) vs. 17 mM (DMEM/F-12). Given the known impact of embryonic nutritional programming on fetal and adult development, we evaluated the effect of glucose concentration during IVM on equine cumulus-oocyte complex (COC) function. Abattoir-derived COCs were held overnight, then cultured for 30 h either in individual 10- μl droplets within a petri dish (Study 1) or directly in a Seahorse XFp Bioanalyser plate (Study 2) in M199 with 10%...
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: N. Lewis, K. Hinrichs, D. Brison, R. Sturmey, C. McG. Argo Source Type: research

Establishing Monolayers of Differentiated Equine Oviduct Epithelial Cells
Conventional in vitro fertilization with equine gametes is not successful. Since fertilization in vivo takes place in the oviductal ampulla, establishing an in vitro oviduct culture system that mimics the in vivo microenvironment might help us define factors involved in sperm activation and fertilization. In a first step towards developing an in vitro oviduct model, monolayers of differentiated equine oviduct epithelial cells (OECs) were established. Oviducts were obtained from slaughtered adult mares (n=11) at random stages of the estrous cycle. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: H.H. Henning, M. Vos, B.M. Gadella, T.A. Stout Source Type: research

Intrafollicular Injection of Prostaglandins in the Preovulatory Follicle of the Mare
The exact role of prostaglandins during the ovulatory process in mammals is not completely understood. This experiment was performed to evaluate whether intrafollicular treatment with PGE2 and PGF2 α administered in early to mid-oestrus (follicle diameter between 35-39 mm), would induce normal ovulation, corpus luteum formation and development, progesterone production, fertilization and embryo development. Six mixed-bred cyclic mares aged 3 to 12 years old and weighing between 350 and 550 Kg were studied during 3 oestrous cycles each, between September 2017 and January 2018. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: J. Aguilar, C. Casta ñeira, C. Alonso, A. Flores, J. Marín, J. Cuervo-Arango, R. Martinez-Boví, H. Mouguelar, L. Losinno Source Type: research

Effect of Meiotic Stage and Warming Medium Equilibration Atmosphere on Equine Oocyte Vitrification
The objectives of this study were to evaluate a commercial human oocyte vitrification method (Cryotech ®) for vitrification of immature and in vitro-matured equine oocytes, with and without cumulus cells, and to evaluate the effect of warming medium equilibration atmosphere on oocyte developmental competence. Cumulus-oocyte complexes (COCs) were obtained from slaughterhouse-derived ovaries. The COCs (n = 551) were held overnight at room temperature, pipetted to ∼4 layers of cumulus cells, then divided into immature (Imm) or in vitro matured (Mat) groups. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: D. Angel, H.S. Canesin, J.G. Brom-de-Luna, K. Hinrichs, S. Morado, G. Dalvit, D. Gomez, N. Posada, R. Urrego, I.C. Velez Source Type: research

Methylation Status and Gene Expression of DNA Methyltransferases, Estrogen Receptor1, and NANOG in Fresh and Short-term Stored Equine Embryos
During the development of preimplantation embryos, a major wave of epigenetic reprogramming takes place to establish the totipotent state. Disturbance during this period may lead to failure in embryo development and maternal recognition. Therefore, this study aimed to evaluate the methylation status and gene expression of estrogen receptor1 (ESR1), NANOG, and DNA methyltransferases (DNMT1, DNMT3a, DNMT3b) in fresh and short-term stored (20 °C or 5°C, 24 h) equine embryos. Equine embryos (n=51) were collected on Day 7 (n=38) or Day 8 (n=13) after ovulation and assigned to 4 groups: Day 7 control (E7F,fresh); Day 7, 24 h a...
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: G.D.A. Gastal, D. Scarlet, R. Ertl, C. Aurich Source Type: research

Early Embryo Development in Mares: Proteomics of Uterine Fluid
The expression and regulation of endometrial proteins is crucial for conceptus implantation and development. However, little is known about site-specific proteomic profiles of the mammalian endometrium during the peri-implantation period [1]. The conceptus-derived signals used for pregnancy recognition have been identified in nearly all of the important domestic animal species; one notable exception is the horse [2]. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: H.B.A. Bastos, G.C. Camozzato, M.N. Martinez, C.E. Vital, P.M.P. Vidigal, E. Barros, R.M. Gregory, M.I.M. Jobim, R.C. Mattos Source Type: research

The Effect of Pre- and Post-injection Procedural Factors on Blastocyst Rate After ICSI
Use of intracytoplasmic sperm injection (ICSI) is increasing in the equine industry, but little information is available on factors affecting embryo production in this system. Often, clinical ICSI is performed in multiple mares using the same semen, of variable quality. Swim-up separation (SU) is thought to select for higher-quality sperm. If insufficient sperm are available in the first preparation, it is unclear if remaining thawed semen can be utilized for a second preparation, as prolonged exposure to components of freezing extender may affect sperm viability. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: J.G. Brom-de-Luna, H.S. Canesin, R.M. Salgado, K. Hinrichs Source Type: research

Equine Oocyte Maturation in a Novel Medium Without CO2 Gas Phase
Recently, the demand for transportation of immature equine oocytes collected by ovum pick up (OPU) for in vitro embryo production has increased. Routinely after recovery, immature oocytes are placed in complex or simple embryo holding media (HM) at room temperature for ∼18h, followed by a CO2 phase incubation (∼30h) before ICSI and culture, with reported cleavage and blastocyst rates of 68-85% and 20-37%, respectively. Simplifying initial processing and maturation of oocytes would provide an efficient alternative while potentially mitigating oxidative stress. (Source: Journal of Equine Veterinary Science)
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: L.F. Campos-Chillon, C.M. Owen, J.L. Altermatt Source Type: research

Endometrial Gene Expression in Pregnant and Non-pregnant Mares on Days 10 and 12 Post Ovulation
Early embryonic loss affects up to 15% of detected pregnancies, and causes significant economic loss in the equine industry. Understanding the mare ’s ability to recognize the presence of an embryo and block the luteolytic signal is key to reducing these losses. Important components of MRP include: prostaglandin F2α, a luteolysin whose secretion is stimulated by oxytocin and mediated by oxytocin receptors; prostaglandin synthase 2 (PTGS2), an enzyme that converts arachidonic acid to endoperoxides, which increases at the time of luteolysis; and oxytocinase (OTase), an enzyme present in the endometrium that metabolizes o...
Source: Journal of Equine Veterinary Science - June 23, 2018 Category: Veterinary Research Authors: M. Diel de Amorim, C. Klein, C.E. Card Source Type: research