Reproduction in horses encompasses the biological processes and mechanisms involved in the breeding and development of equine offspring. This includes the study of reproductive anatomy, physiology, and endocrinology in both mares and stallions. Key areas of interest include the estrous cycle, ovulation, conception, gestation, and parturition. Researchers also examine factors influencing fertility, reproductive technologies such as artificial insemination and embryo transfer, and management practices that impact reproductive success. This page compiles peer-reviewed research studies and scholarly articles that explore the physiological, genetic, and environmental aspects of equine reproduction.
Risvanli A, Salykov R, Timurkaan N, Seker I, Ekinci E.This study was conducted to examine glandular histological changes in the uterus of Kyrgyz breed mares during the first 6 months of pregnancy. The study used 53 Kyrgyz breed mares; 43 of these were at different stages of pregnancy, while 10 were non-pregnant mares. Uterine samples obtained at the slaughterhouse were evaluated histomorphometrically; endometrial thickness, gland density, gland epithelial height and gland diameter were measured. In conclusion, it was concluded that in Kyrgyz mares, endometrial thickness, glandular epithelial height and diameter increased as pregnancy progressed...
Pinto-Bravo P, Rebordão MR, Amaral AS, Szóstek-Mioduchowska A, Fernandes C, Galvão AM, Silva E, Alpoim-Moreira J, da Costa RPR, Skarzynski DJ....Oviduct glycoprotein 1 (OVGP1) is a key protein involved in oviductal functions. β-estradiol (E) and progesterone (P), oxytocin (OXT) and tumor necrosis factor-α (TNFα) modulate the equine oviduct function, through prostaglandin regulation. The objective was to evaluate OVGP1 expression within each equine oviduct segment (infundibulum, ampulla isthmus), throughout the estrous cycle. The in vitro effect of (i) E, P, OXT, TNFα; and (ii) spermatozoa, on oviduct OVGP1 transcription and secretion was studied. Gene transcription was assessed by real-time PCR; protein expression by western blot; ...
Mendoza Cerna MN, Anderson H, Avni G, Kahila Bar-Gal G, Juras R, Raudsepp T.Robertsonian translocations (ROBs) or centric fusions of acrocentric chromosomes are the most common structural chromosomal rearrangements in mammals. ROBs are of medical and veterinary concern because of associated subfertility and congenital disorders but are also of interest as a mechanism of chromosome and karyotype evolution. While ROBs are well documented in humans, mice, and cattle/bovids, they are extremely rare in horses, despite the 18 acrocentric chromosomes in the horse karyotype. Methods: We characterize the case using conventional and molecular cytogenetic approaches and DNA anal...
Otero JC, Neild DM, Ferrante AA, Gambarotta MC, Caldevilla ML.Glycerol, a penetrating cryoprotectant, is most employed for deep freezing spermatozoa. However, it can induce toxic, chemical, and osmotic effects, altering the lipid structure of the sperm membrane. Rapid glycerol addition has been demonstrated to have fewer toxic effects than its removal. Objective: To minimize both the toxic and osmotic effects of glycerol on equine sperm through post-thaw dilution using two different extenders. Methods: Samples of equine semen frozen with 5% glycerol from nine stallions were thawed, re-diluted 1:2, and incubated for 30 minutes at 22°C in Tyrodes (Tyr) an...
Fresa K, Catandi GD, Gonzalez-Castro R, Omar A, Whitcomb LA, Cheng MH, Chen TW, Carnevale EM, Chicco AJ.Advancing age is associated with a decline in fertility and functional capacity, which may result in part from suboptimal nutrition and impaired mitochondrial function. Dietary essential polyunsaturated fatty acids (PUFA) are broadly recommended to mitigate weight loss and reduce risk of chronic disease in aged populations, but their effects on mitochondrial function are less clear. The present study investigated the impacts of dietary supplementation with essential omega-3 PUFA (flaxseed oil; N3) or omega-6 PUFA (corn oil, N6) on blood, muscle and follicular cell fatty acid composition and mi...
Ferrara MA, Preziosi G, Boni R, Ruggiero R, Gualandi SC.This study employs Holographic tomography (HT) to examine structural and biophysical changes occurring during the cryopreservation of stallion sperm. HT is an advanced imaging technique that integrates digital holography with tomography to achieve three-dimensional, quantitative reconstructions of objects without the need for treatment or reporter dyes. By using refractive index (RI) intervals to represent specific structural regions of sperm cells, variations in optical density, surface area, volume, and dry mass across different cryopreservation extenders and donors have been quantified. Thr...
Mules (Equus mulus), as sterile hybrids between mares and donkeys, present a unique uterine morphology and physiology that remains poorly characterized. This study provides the first histomorphometric evaluation and transcriptional profiling of the endometrium in adult mules. To achieve this, endometrial biopsies were analysed using quantitative stereology, histological classification (Kenney-Doig system), and qPCR of key immune-related and fibrotic genes. Histometric analyses revealed that the stratum spongiosum was the predominant component of the mule endometrium (mean volume density: 84.7...
Song D, Wang G, Baterin T, Weng Y, Dugarjaviin M, Li B.Normal spermatogenesis in Mongolian horses depends on the mitotic division of spermatogonia, two successive meiotic divisions, and the morphological transformation of spermatids into mature spermatozoa. The gene is involved in the meiosis cycle and is required for normal chromosome association during meiosis. Previous studies have shown that alternative splicing of may promote spermatogenesis in Mongolian horses. In this paper, the regulatory effects of different alternative splicing events on Mongolian horse spermatogenesis are investigated. Results: In this study, two overexpressed lentiv...
Tainturier D, Tainturier B, Michaud S, Briand-Amirat L, Topie E, Moreno D.A total of 147 mares of different breeds (110 were sport or race horses, often very valuable) have been monitored over 5 years from 2012 to 2016. When at or near term, the mares were monitored in order to induce foaling, by checking the mammary development by palpation, analysing the colour and consistency of the precolostrum, estimating the calcium and antibodies concentrations in the precolostrum and by measuring the plasmatic progestagens concentration every day at 6 p.m. At the end of gestation, it has been observed that the progestagens rate levelled off (the top concentration varies from...
Da Silva-Álvarez E, Martín-Cano FE, Alonso JM, Becerro-Rey L, Zabalo-Palomo C, Gil MC, Peña FJ, Ortega-Ferrusola C.This study aims to characterize and compare the uterine fluid proteome and cytokine profile of reproductively healthy mares (HM; n = 15) and mares with Streptococcus equi subsp. zooepidemicus (S. zooepidemicus)-associated endometritis (SAE; n = 9). Uterine flush samples collected during the follicular phase were analyzed by shotgun proteomics and multiplex cytokine assays. Equine proteins were mapped to human orthologs, and enrichment and network analyses were performed using g:Profiler, Metascape, ToppGene, and STRING/MCODE. SAE mares showed higher levels of IL-1α, IL-1β, GRO, IL12p...
Martin-Pelaez S, Orsolini M, Verstraete M, de la Fuente A, Takahashi K, Meyers S, Dini P.Equine in vitro embryo production (IVP) offers a valuable opportunity to enhance the efficient utilization of genetically and economically valuable horses. In cases of subfertility, sudden death, emergency euthanasia, or limited sperm availability, IVP becomes the only viable option to produce offspring. Due to steadily improving success rates, IVP has become one of the most sought-after assisted reproductive techniques. The rising global demand has created a clear need for veterinarians and stallion owners to provide IVP-suitable sperm, where the selection of intact sperm for intracytoplasmic...
Silva JA, Vasquetto A, Mouguelar H, Nader-Macías MEF, Pellegrino MS.Equine endometritis, a major cause of subfertility in mares, has a significant economic impact on horse breeding. In the face of rising antimicrobial resistance, the use of beneficial bacteria to prevent this disease is a non-antibiotic alternative which aligns with "One Health" principles. This study characterised vaginal autochthonous lactic acid bacteria (LAB) from healthy mares. Out of the 25 presumptive LAB isolates obtained from 15 clinically healthy thoroughbred mares, 24 were confirmed. Surface properties were assessed (autoaggregation, hydrophobicity, biofilm formation, exopolysacchar...
Sala-Ayala L, Cuervo-Arango J, Martínez Boví R.Endometrial edema is an ultrasonographic sign of estrus in mares and is positively associated with fertility. This study aimed to evaluate the influence of follicular size, systemic progesterone (P4), and exogenous estradiol benzoate (EB) on the onset and duration of endometrial edema. In Experiment 1, anestrus (n = 4) and diestrus mares (n = 4) received 4 mg of EB intramuscularly; edema scores and plasma P4 were monitored over four days. In a complementary group (n = 5), mares were monitored until ovulation, then administered 4 mg of EB and examined every 12 h for 48 h. In Experimen...
Derar D, Ali A, Al-Sobayil F, Refaai W.Granulosa cell tumors (GCTs) represent the most common ovarian neoplasms in mares, yet data on their epidemiology, risk factors, and clinical outcomes in Arabian horses are limited. Understanding their prevalence and diagnostic features is crucial for improving fertility management in this breed. Unassigned: Clinical records from 807 Arabian mares housed on 35 stud farms in central Saudi Arabia were retrospectively reviewed to determine the prevalence of GCT and potential risk factors, including age, parity, and anabolic steroid use. Twenty-four confirmed cases were further investigated using ...
Solanki O, Talluri TR, Jhamb D, Kumar S, Pargi KK, Paul N, Kutty M, Dedar RK, Meena M, Gaur M, Bhattacharya TK.The current study evaluated the effect of L-Carnitine supplementation to the stallion semen extender on pre-freeze and post-thaw semen quality and oxidative parameters in Marwari breed stallions. Methods: For this purpose, thirty-six semen ejaculates (6 ejaculates from each stallion) were collected using an artificial vagina (AV) from six adult Marwari stallions. The gel free semen was extended with different concentrations of L-Carnitine (LC) i.e. 0 mM (control), 2.5 mM (T1), 5 mM (T2) and 10 mM (T3). Pre-freeze and post-thaw semen evaluations were conducted for various seminal attributes and...
Broothaers K, Jouneau A, Angel-Velez D, De Coster T, Festuccia N, Archilla C, Calderari S, Jouneau L, Van den Branden E, Peere S, Polfliet E....In vitro production of equine embryos has been performed using intracytoplasmic sperm injection (ICSI) for the last two decades. Since 2022, a repeatable protocol for conventional in vitro fertilization (IVF) provides a successful alternative. However, little is known about the influence of the fertilization method on embryo quality and the transcriptomic profile. In this study, we aimed to examine differentially expressed genes (DEGs) between ICSI and IVF embryos in the horse. Therefore, ten equine sibling blastocysts, produced in vitro by either ICSI or IVF from three different mares, were s...
Ali A, Derar DR, Alaeyeari AA, Alharbi YM.This study aimed to monitor intrauterine fetal growth, establish predictive equations for gestational age estimation, and determine the optimal period for fetal sexing in Arabian horses using ultrasonography. Unassigned: Seven Arabian mares were monitored from insemination to parturition using transrectal ultrasonography. The following fetal and embryonic parameters were measured: embryonic vesicle (EV), crown-rump length (CRL), biparietal diameter (BIP), stomach diameter (STD), chest depth (CHD), abdominal diameter (ABD), kidney length (KDL), eyeball diameter (EBD), and eye lens length (ELL)....
de Zutter BM, de Paula Freitas-Dell'Aqua C, Dell'Aqua-Junior JA, Monteiro GA, Troncarelli T, Papa FO.This study evaluated the effects of cholesterol, pentoxifylline and casein, with or without skim milk, added to extenders during pre-centrifugation on equine sperm cryosurvival. Seven ejaculates from four stallions (n = 28) were divided into four groups: SM (skim milk), SMP (SM + pentoxifylline), SMCho (SM + cholesterol) and ChoCa (cholesterol + casein). After centrifugation and freezing, sperm kinematics and plasma membrane integrity were assessed immediately and 30 min post-thaw. SMCho and ChoCa showed superior results compared with SM and SMP. These findings indicate that chol...
Feijo LS, Ledeck J, Wolfsdorf K, Ponthier J, Parry S, Felippe MJB.Associations between the immune and endocrine systems during equine pregnancy remain poorly understood. Based on the hypothesis that distinct phases of the equine healthy gestation are characterized by specific associations between circulating immunological and hormonal parameters, contributing to pregnancy maintenance, this investigation aimed to: (i) evaluate how circulating immunological and hormonal parameters change across different phases of pregnancy; (ii) investigate associations between changes in circulating immunological and hormonal parameters; and (iii) propose potential hormonal ...
Roxon CA, Deacon LJ, Abraham M, Stefanovski D, Sertich PL.Gestation length is not a reliable indicator of fetal maturity due to the variability of normal gestation length in the mare. A standard method to accurately predict equine fetal maturity is not being used clinically. The presence of continuous gastrointestinal peristalsis, as detected ultrasonographically, is an indicator that both human and canine fetuses are mature (can survive after elective cesarean section). To determine if continuous gastrointestinal peristalsis, which we termed Phase 5, was a valid indicator of fetal maturity in the horse, and whether this indicator varied in late-gest...
Boakari Y, El-Sheikh Ali H, Almeida GHDR, Scoggin KE, Fernandes CB, Marchio SP, Troedsson MHT, Carreira ACO.Equine placental dysfunction impairs fetal growth and disrupts pregnancy outcomes. Despite many advances in diagnosis, the molecular pathophysiology of equine placentitis and premature placental separation remains poorly understood. However, the hypoxia-inducible factor (HIF-α) pathway is related to placental hypoxia, and its modulation in placental diseases has been shown in other species. Therefore, we hypothesized that in conditions marked by equine placental dysfunction, oxygen deprivation in the chorioallantois membrane triggers the activation of the HIF-α pathway, which is related to m...
Dindo S, Tovar-Pascual L, Baldassarro VA, Bucci D, Mislei B, Spinaci M, Ortiz-Rodriguez JM.Nanoplastics (NP) accumulation in biological tissues and their adverse effects on fertility through inflammatory and oxidative stress responses have recently been described as consequences of global plastic pollution. However, little is known about the impact of NP on gametes. This study aimed to assess the internalization of NP and their effects on mature equine spermatozoa. Frozen-thawed ejaculates from five stallions were divided into untreated control (CTR) and samples supplemented with different concentrations (10, 50, 100 and 200 μg/mL) of 30 nm polystyrene NP. At baseline (T0), and a...
Khan Y, Gautier C, Aurich C, El-Shalofy A.Letrozole is a potent and highly selective third-generation aromatase inhibitor. In the present study, we aimed to investigate the effects of letrozole treatment of non-pregnant mares on estrous cycle characteristics. Cyclic, non-lactating mares (n = 9) were included. After estrus synchronization, mares were monitored to detect ovulation (d0:) of the treatment cycle. Each three mares were randomly assigned to one of three treatments: control, 0.5, and 1 mg/kg body weight letrozole in three consecutive cycles (d7 to d13 of the treatment cycle). Mares were inseminated in the estrus after trea...
de Lara NSS, Weiss RR, Oba E, Kozicki LE, Souza FA, Bergstein-Galan TG, Muehlbauer E, Silvestri M, de Lima PHL, Vaz ES.In equine reproduction, determining foetal sex is of economic and strategic importance, but currently available methods are often invasive, costly, or require specialised expertise. This study aimed to assess whether plasma progesterone concentrations could serve as a predictive tool for foetal sex determination in Criollo mares between the 4th and 8th months of gestation and to determine whether these measurements could identify foetal sex. Blood samples were collected at 30-day intervals from 17 Crioula mares between 114 days and 240 days of gestation. Maternal plasma progesterone concen...
Gomes VCL, Strachota JR.This article explores key complications in equine reproduction, focusing on their causes, diagnosis, treatment, and prevention. It emphasizes the risks associated with common procedures, particularly those that are iatrogenic, meaning caused by medical intervention. The discussion highlights how understanding these risks can help in early detection and management, ultimately improving reproductive success and animal welfare. The article also provides insights into best practices to minimize complications, ensuring safer procedures and better outcomes for breeding horses.
Thomé C, Márquez-Moya A, Sala-Ayala L, Carreras-Vico N, Cuervo-Arango J.Post-mortem oocyte collection serves to preserve the genetic material of valuable mares and to obtain recipient oocytes for cloning purposes. Therefore, the number of oocytes retrieved per ovary is a critical factor in increasing the likelihood of obtaining a viable embryo. This study evaluated the efficiency of two post-mortem oocyte retrieval techniques: follicular scraping (Scraping) and ultrasound-guided follicular aspiration (OPU). The comparison was based on several parameters, including the number of follicles aspirated per ovary, oocyte recovery rate (ORR), number of oocytes obtained p...
Moore HL, Klabnik JL, Boothe DM, Cruz-Espindola C, Mita N, Thungrat K, Babu RJ, Lyman CC.To investigate the IV pharmacokinetic parameters of clomiphene citrate (CC), a selective estrogen receptor modulator, in mares. Unassigned: This was an experimental study to assess the pharmacokinetic parameters of CC in the mare. Eight mares received a single 2,000-mg dose of IV CC to identify plasma concentrations over 336 hours. Following this, 6 mares received a multidose regimen of IV CC (2,000 mg, q 24 h) for 5 days to identify trough plasma concentration each day. Unassigned: CC was well tolerated, demonstrated a short elimination half-life of 4.95 ± 1.10 hours and a mean residence tim...
Newcombe JR, Claes AN, Cuervo-Arango J.Early embryonic loss (EEL), particularly between Days 14 and 42 of pregnancy, remains a key concern in equine reproduction. This study investigates the incidence of spontaneous luteolysis-used here as a marker of maternal recognition of pregnancy (MRP) failure-in both pregnant Thoroughbred (TB) broodmares and recipient mares carrying either in vivo-derived (IVD) or in vitro-produced (IVP) embryos. Retrospective reproductive data from 2078 pregnancies in TB and 532 pregnancies in recipients were analysed to determine the incidence and characteristics of clinical luteolysis during pregnancy. Ove...
Aitken RJ, Gibb Z, Mitchell LA, Lambourne SR, Connaughton HS, De Iuliis GN.The prolonged incubation of human spermatozoa in vitro was found to induce a loss of motility associated with the activation of mitochondrial reactive oxygen species generation in the absence of any change in mitochondrial membrane potential. The increase in mitochondrial free radical production was paralleled by a loss of protein thiols and a concomitant rise in the formation of 4-hydroxynonenal, an electrophilic product of lipid peroxidation that was found to directly suppress sperm movement. These results prompted a search for nucleophiles that could counteract the action of such cytotoxic ...
Kenney RM.Normal histologic changes that occurred in concert with the ovarian cycle were evaluated. When combined with behavioral and physical findings, this evaluation enabled determination when there was synchrony between ovarian steroids (estrogen and progesterone) and their target tissues of endometrium. A system for classification as well as definitions of patterns types and degrees of severity of inflammatory and fibrotic changes was developed to facilitate a uniform system for description and communication. An attempt was made to relate the pathologic changes to their effect on fertility when fer...
Ball BA.Oxidative stress is an important component of the cytopathology of equine spermatozoa undergoing storage as liquid or frozen semen. Damage to chromatin, membranes and proteins of sperm are important components of oxidative damage to sperm. Similarly, sperm are exposed to a variety of osmotic stresses during storage that result from exposure to hypertonic media or result as a consequence of osmotic changes induced during freezing. A number of changes induced during processing and storage of equine sperm also appear to induce apoptotic-like changes which may adversely affect sperm survival and f...
de Laat MA, McGree JM, Sillence MN.Compared with some other species, insulin dysregulation in equids is poorly understood. However, hyperinsulinemia causes laminitis, a significant and often lethal disease affecting the pedal bone/hoof wall attachment site. Until recently, hyperinsulinemia has been considered a counterregulatory response to insulin resistance (IR), but there is growing evidence to support a gastrointestinal etiology. Incretin hormones released from the proximal intestine, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide, augment insulin secretion in several species but require invest...
Plaza Davila M, Martin Muñoz P, Tapia JA, Ortega Ferrusola C, Balao da Silva C C, Peña FJ.Mitochondria have been proposed as the major source of reactive oxygen species in somatic cells and human spermatozoa. However, no data regarding the role of mitochondrial ROS production in stallion spermatozoa are available. To shed light on the role of the mitochondrial electron transport chain in the origin of oxidative stress in stallion spermatozoa, specific inhibitors of complex I (rotenone) and III (antimycin-A) were used. Ejaculates from seven Andalusian stallions were collected and incubated in BWW media at 37 °C in the presence of rotenone, antimycin-A or control vehicle. Incubation...
Wallner B, Vogl C, Shukla P, Burgstaller JP, Druml T, Brem G.The paternally inherited Y chromosome displays the population genetic history of males. While modern domestic horses (Equus caballus) exhibit abundant diversity within maternally inherited mitochondrial DNA, no significant Y-chromosomal sequence diversity has been detected. We used high throughput sequencing technology to identify the first polymorphic Y-chromosomal markers useful for tracing paternal lines. The nucleotide variability of the modern horse Y chromosome is extremely low, resulting in six haplotypes (HT), all clearly distinct from the Przewalski horse (E. przewalskii). The most wi...
Ezashi T, Yuan Y, Roberts RM.This review deals with the latest advances in the study of embryonic stem cells (ESC) and induced pluripotent stem cells (iPSC) from domesticated species, with a focus on pigs, cattle, sheep, goats, horses, cats, and dogs. Whereas the derivation of fully pluripotent ESC from these species has proved slow, reprogramming of somatic cells to iPSC has been more straightforward. However, most of these iPSC depend on the continued expression of the introduced transgenes, a major drawback to their utility. The persistent failure in generating ESC and the dependency of iPSC on ectopic genes probably s...
Riddle WT, LeBlanc MM, Stromberg AJ.Endometrial cytology and culture specimens (n=2123) were collected concurrently with a guarded uterine culture instrument from 970 mares (738 barren, 1230 foaling and 155 maiden mares) during three breeding seasons (2001-2004). Results were compared to the 28-d pregnancy rate for the cycle from which the samples were taken. Cytological smears were evaluated for inflammation at x100 and graded as: not inflammatory (0-2 neutrophils/field), moderate inflammation (2-5 neutrophils/field), severe inflammation (>5 neutrophils/field), or hypocellular (scant epithelial cells and no neutrophils). Ute...
Su TW, Choi I, Feng J, Huang K, McLeod E, Ozcan A.We report the discovery of an entirely new three-dimensional (3D) swimming pattern observed in human and horse sperms. This motion is in the form of 'chiral ribbons', where the planar swing of the sperm head occurs on an osculating plane creating in some cases a helical ribbon and in some others a twisted ribbon. The latter, i.e., the twisted ribbon trajectory, also defines a minimal surface, exhibiting zero mean curvature for all the points on its surface. These chiral ribbon swimming patterns cannot be represented or understood by already known patterns of sperms or other micro-swimmers. The...
Iacono E, Brunori L, Pirrone A, Pagliaro PP, Ricci F, Tazzari PL, Merlo B.Mesenchymal stem cells (MSCs) have been derived from multiple sources of the horse including umbilical cord blood (UCB) and amnion. This work aimed to identify and characterize stem cells from equine amniotic fluid (AF), CB and Wharton's Jelly (WJ). Samples were obtained from 13 mares at labour. AF and CB cells were isolated by centrifugation, while WJ was prepared by incubating with an enzymatic solution for 2 h. All cell lines were cultured in DMEM/TCM199 plus fetal bovine serum. Fibroblast-like cells were observed in 7/10 (70%) AF, 6/8 (75%) CB and 8/12 (66.7%) WJ samples. Statistically ...
Janečka JE, Davis BW, Ghosh S, Paria N, Das PJ, Orlando L, Schubert M, Nielsen MK, Stout TAE, Brashear W, Li G, Johnson CD, Metz RP, Zadjali AMA....Dynamic evolutionary processes and complex structure make the Y chromosome among the most diverse and least understood regions in mammalian genomes. Here, we present an annotated assembly of the male specific region of the horse Y chromosome (eMSY), representing the first comprehensive Y assembly in odd-toed ungulates. The eMSY comprises single-copy, equine specific multi-copy, PAR transposed, and novel ampliconic sequence classes. The eMSY gene density approaches that of autosomes with the highest number of retained X-Y gametologs recorded in eutherians, in addition to novel Y-born and transp...
Radin MJ, Sharkey LC, Holycross BJ.In addition to its role as an energy storage depot, adipose tissue is now recognized as a complex endocrine organ. Adipose tissue releases a variety of factors, termed adipokines, that regulate energy metabolism, cardiovascular function, reproductive status, and immune function. Some of the better-studied adipokines include leptin, adiponectin, and components of the renin-angiotensin system such as angiotensinogen. The function of more recently discovered adipokines such as resistin are under intense scrutiny. Abnormal production or regulation of adipokines occurs in obese individuals and is i...
Druart X, Rickard JP, Mactier S, Kohnke PL, Kershaw-Young CM, Bathgate R, Gibb Z, Crossett B, Tsikis G, Labas V, Harichaux G, Grupen CG, de Graaf SP.Seminal plasma contains a large protein component which has been implicated in the function, transit and survival of spermatozoa within the female reproductive tract. However, the identity of the majority of these proteins remains unknown and a direct comparison between the major domestic mammalian species has yet to be made. As such, the present study characterized and compared the seminal plasma proteomes of cattle, horse, sheep, pig, goat, camel and alpaca. GeLC-MS/MS and shotgun proteomic analysis by 2D-LC-MS/MS identified a total of 302 proteins in the seminal plasma of the chosen mammali...
da Silveira JC, Carnevale EM, Winger QA, Bouma GJ.Ovarian follicle growth and maturation requires extensive communication between follicular somatic cells and oocytes. Recently, intercellular cell communication was described involving cell-secreted vesicles called exosomes (50-150 nm), which contain miRNAs and protein, and have been identified in ovarian follicular fluid. The goal of this study was to identify a possible role of exosomes in follicle maturation. Methods: Follicle contents were collected from mares at mid-estrous (~35 mm, before induction of follicular maturation) and pre-ovulatory follicles (30-34 h after induction of folli...
Benachour N, Sipahutar H, Moslemi S, Gasnier C, Travert C, Séralini GE.Roundup is the major herbicide used worldwide, in particular on genetically modified plants that have been designed to tolerate it. We have tested the toxicity and endocrine disruption potential of Roundup (Bioforce on human embryonic 293 and placental-derived JEG3 cells, but also on normal human placenta and equine testis. The cell lines have proven to be suitable to estimate hormonal activity and toxicity of pollutants. The median lethal dose (LD(50)) of Roundup with embryonic cells is 0.3% within 1 h in serum-free medium, and it decreases to reach 0.06% (containing among other compounds 1.2...
Hoffmann C, Ellenberger C, Mattos RC, Aupperle H, Dhein S, Stief B, Schoon HA.This paper describes the histomorphological and immunohistochemical characterisation of phenotypic variations of endometrosis as well as potential etiological factors which may influence disease progression. In total, 779 endometrial biopsies were examined. These biopsies were taken in the breeding and non-breeding season (n=509), on defined days during the estrous cycle (n=70) and before and after experimentally induced bacterial endometritis (n=200). In addition to conventional histopathology, selected biopsies were investigated using alcianblue staining as well as immunohistochemical method...
H A Morris L, M McCue P, Aurich C.Endometritis in the mare begins as a normal physiological inflammatory response to breeding that involves both a mechanical and immunological response pathway activated to rid the uterus of semen and bacteria. With successful resolution of this inflammation, the mare's uterus will provide a hospitable environment for the development of the semi-allogenic conceptus. If the mare fails to resolve this inflammatory response within 48 h of breeding, she will become susceptible to persistent breeding-induced endometritis (PBIE) which will have detrimental effects on her fertility. This condition can...
Hoynowski SM, Fry MM, Gardner BM, Leming MT, Tucker JR, Black L, Sand T, Mitchell KE.Stem cells are being evaluated in numerous human clinical trials and are commercially used in veterinary medicine to treat horses and dogs. Stem cell differentiation, homing to disease sites, growth and cytokine factor modulation, and low antigenicity contribute to their therapeutic success. Bone marrow and adipose tissue are the two most common sources of adult-derived stem cells in animals. We report on the existence of an alternative source of primitive, multipotent stem cells from the equine umbilical cord cellular matrix (Wharton's jelly). Equine umbilical cord matrix (EUCM) cells can be ...
Baumber J, Ball BA, Linfor JJ, Meyers SA.The objective of this study was to examine the effect of reactive oxygen species (ROS) and cryopreservation on DNA fragmentation of equine spermatozoa. In experiment 1, equine spermatozoa were incubated (1 hour, 38 degrees C) according to the following treatments: 1) sperm alone; 2) sperm + xanthine (X, 0.3 mM)-xanthine oxidase (XO, 0.025 U/mL); 3) sperm + X (0.6 mM)-XO (0.05 U/mL); and 4) sperm + X (1 mM)-XO (0.1 U/mL). In experiment 2, spermatozoa were incubated (1 hour, 38 degrees C) with X (1 mM)-XO (0.1 U/mL) and either catalase (200 U/mL), superoxide dismutase (SOD, 200 U/mL), or reduced...
Ambruosi B, Uranio MF, Sardanelli AM, Pocar P, Martino NA, Paternoster MS, Amati F, Dell'Aquila ME.Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of...
Weems CW, Weems YS, Randel RD.Prostaglandins impact on ovarian, uterine, placental, and pituitary function to regulate reproduction in female livestock. They play important roles in ovulation, luteal function, maternal recognition of pregnancy, implantation, maintenance of gestation, microbial-induced abortion, parturition, postpartum uterine and ovarian infections, and resumption of postpartum ovarian cyclicity. Prostaglandins have both positive and negative effects on reproduction; they are used to synchronize oestrus, terminate pseudopregnancy in mares, induce parturition, and treat retained placenta, luteinized cysts, ...
Sieme H, Oldenhof H, Wolkers WF.Native sperm is only marginally stable after collection. Cryopreservation of semen facilitates transport and storage for later use in artificial reproduction technologies, but cryopreservation processing may result in cellular damage compromising sperm function. Membranes are thought to be the primary site of cryopreservation injury. Therefore, insights into the effects of cooling, ice formation and protective agents on sperm membranes may help to rationally design cryopreservation protocols. In this review, we describe membrane phase behaviour of sperm at supra- and subzero temperatures. In a...
Davila MP, Muñoz PM, Bolaños JM, Stout TA, Gadella BM, Tapia JA, da Silva CB, Ferrusola CO, Peña FJ.To investigate the hypothesis that oxidative phosphorylation is a major source of ATP to fuel stallion sperm motility, oxidative phosphorylation was suppressed using the mitochondrial uncouplers CCCP and 2,4,-dinitrophenol (DNP) and by inhibiting mitochondrial respiration at complex IV using sodium cyanide or at the level of ATP synthase using oligomycin-A. As mitochondrial dysfunction may also lead to oxidative stress, production of reactive oxygen species was monitored simultaneously. All inhibitors reduced ATP content, but oligomycin-A did so most profoundly. Oligomycin-A and CCCP also sign...
Rathi R, Honaramooz A, Zeng W, Turner R, Dobrinski I.Grafting of testis tissue from immature animals to immunodeficient mice results in complete spermatogenesis, albeit with varying efficiency in different species. The objectives of this study were to investigate if grafting of horse testis tissue would result in spermatogenesis, and to assess the effect of exogenous gonadotropins on xenograft development. Small fragments of testis tissue from 7 colts (2 week to 4 years of age) were grafted under the back skin of castrated male immunodeficient mice. For 2 donor animals, half of the mice were treated with gonadotropins. Xenografts were analyzed a...
Ortega-Ferrusola C, Sotillo-Galán Y, Varela-Fernández E, Gallardo-Bolaños JM, Muriel A, González-Fernández L, Tapia JA, Peña FJ.The kinematics of the appearance of apoptotic markers was studied by flow cytometry and immunoblot assays in equine spermatozoa subjected to freezing and thawing. Caspase activity, low mitochondrial membrane potential, and increases in sperm membrane permeability were observed in all of the phases of the cryopreservation procedure. Freezing and thawing caused an increase in membrane permeability and changes in the pattern of caspase activity; decreases in mitochondrial membrane potential were observed after centrifugation and cooling to 4 degrees C and after freezing and thawing. It is propose...
Linklater WL, Cameron EZ, Minot EO, Stafford KJ.Feral horse, Equus caballus, breeding groups, called bands, usually include one but sometimes up to five stallions. We found that mares were loyal to single-stallion (SS) or multistallion (MS) bands or were social dispersers (maverick mares, Mv). The spacing and social behaviour of mares and stallions in single- and multistallion bands was measured. Indices of mare well-being were also measured including activity budgets (feeding: MS>SS=Mv; resting: MSSS), maternal effort in maintaining contact with foals (MS=Mv>SS), parasite levels in faeces (MS>Mv>SS), body condition (MS=Mv<SS...
Kirkpatrick JF, Lyda RO, Frank KM.Wildlife, free-ranging and captive, poses and causes serious population problems not unlike those encountered with human overpopulation. Traditional lethal control programs, however, are not always legal, wise, safe, or publicly acceptable; thus, alternative approaches are necessary. Immunocontraception of free-ranging wildlife has reached the management level, with success across a large variety of species. Thus far, the immunocontraceptive research and management applications emphasis have been centered on porcine zona pellucida and gonadotropin-releasing hormone vaccines. Contraceptive succ...
Rathi R, Colenbrander B, Bevers MM, Gadella BM.The primary aim of this study was to establish a flow cytometric technique for determining the capacitation status of stallion spermatozoa. To this end, a flow cytometric technique that demonstrates changes in plasma membrane fluidity; namely, merocyanine 540 staining, was compared with the more conventional Ca(2+)-dependent fluorescence microscopic technique, chlortetracycline (CTC) staining, for assessing capacitation status. In addition, the effect of bicarbonate/CO(2) on the progress of capacitation and the acrosome reaction (AR) and on temporal changes in sperm motility, with particular r...
