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.
Crowell CN, Fenton JM, Perry EB.Gustatory and olfactory changes have been reported during gestation in multiple species. However, few data are available regarding feeding preferences in gestating mares. The objective of this research was to evaluate the effect of oil-based palatants on feeding behavior in late term gestating mares. Late-term gestating mares (n = 5) and reproductively sound, open mares (n = 4) were evaluated via paired preference testing during the final 120 days of gestation. Oil-based flavors (corn oil, anise, and apple) were topically applied to a basal pelleted diet (0.375 ml/0.23 kg). Diets were offe...
Diel de Amorim M, Bramer SA, Rajamanickam GD, Klein C, Card C.Our understanding of the temporal changes in endometrial and luteal gene transcripts related to the actions of oxytocin and prostaglandin during early equine pregnancy is incomplete. Additionally, the role of oxytocinase, also known as Leucyl-cystinyl aminopeptidase (LNPEP), during early pregnancy in mares has not been previously investigated. Luteal and endometrial biopsies were obtained on Day (D)8, D10, D12 and D15 post-ovulation in pregnant (PREG) and diestrus (DIEST) mares for real-time qPCR. Differences in endometrial gene expression occurred over time in: SLC2A4, SLC2A1, PTGES, OXTR and...
Possessing high meat and dairy productivity and good reproductive and adaptive qualities to year-round grazing, the Kushum breed plays an exceptional role in the improvement of productive qualities in horse herding in Kazakhstan and the former Soviet republics. The aim of the study was to develop breeding methods for creating new highly productive breeding lines for the Kushum breed horses. The leading method was linebreeding, which is based on the systematic use of remarkable animals, the offspring of which will accumulate and develop all the desired qualities and traits. The practical signif...
Holyoak GR, Premathilake HU, Lyman CC, Sones JL, Gunn A, Wieneke X, DeSilva U.The goal of this study was to understand the composition and existence of the resident uterine microbiome in healthy mares and to establish the presence of a core microbiome for the healthy equine uterus. We analyzed the microbiomes of 35 healthy mares that are long-time residents of three farms in Oklahoma, Louisiana, and Australia as well as that of 19 mares purchased from scattered owners in the Southern Mid-Western states of the United States. Over 6 million paired-end reads of the V4 region of the 16S rRNA gene were obtained resulting in 19,542 unique Amplicon Sequence Variants (ASVs). AS...
Di Azevedo MIN, Lilenbaum W.Leptospirosis may be associated with important syndromes in equines, including reproductive ones. Recently, our group demonstrated a reproductive syndrome of leptospirosis in ruminants (Bovine Genital Leptospirosis - BGL), that presents its own agent, particular diagnostic methods, and specific treatment and prevention, requiring special attention. We realized that the genital syndrome of leptospirosis may not be exclusive to ruminants and may also affect horses. The aim of the present study is to gather the available data on leptospirosis in equine reproduction and propose a new genital lepto...
Tasma Z, Hou W, Damani T, Seddon K, Kang M, Ge Y, Hanlon D, Hollinshead F, Hisey CL, Chamley LW.Mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) have shown promise as off-the-shelf therapeutics; however, producing them in sufficient quantities can be challenging. In this study, MSCs were isolated from preimplantation equine embryos and used to produce EVs in two commercially available bioreactor designs. Mesenchymal stromal cells (MSC) have recently been explored for their potential use as therapeutics in human and veterinary medicine applications, such as the treatment of endometrial inflammation and infertility. Allogeneic MSC-derived extracellular vesicles (EVs) may...
He HY, Liu LL, Chen B, Xiao HX, Liu WJ.Donkey milk has high nutritional and medicinal value, but there are few researches in donkey milk traits, especially on genome. The whole lactation of 89 donkeys was recorded and it was found that Xinjiang donkey had good lactation performance while great differences among individuals. In our previous study, four genes including , , and were identified as milk-associated with Chinese Kazakh house, based on Equine 670k Chip genomic analysis. And then 15 SNPs of the four key genes were conducted for genotyping in Xinjiang donkey in this study, one of Chinese indigenous breed, 14 SNPs were succ...
Kudrimoti S, Machin J, Arojojoye AS, Awuah SG, Eisenberg R, Fenger C, Maylin G, Lehner AF, Tobin T.Based on structural similarities and equine administration experiments, Barbarin, 5-phenyl-2-oxazolidinethione from Brassicaceae plants, is a possible source of equine urinary identifications of aminorex, (R,S)-5-phenyl-4,5-dihydro-1,3-oxazol-2-amine, an amphetamine-related US Drug Enforcement Administration (DEA) controlled substance considered illegal in sport horses. We now report the synthesis and certification of d -barbarin to facilitate research on the relationship between plant barbarin and such aminorex identifications. D -barbarin synthesis commenced with production of d -2-oxo-2-phe...
Sielhorst J, Roggel-Buecker U, Neudeck KC, Kahler A, Rohn K, Luettgenau J, Bollwein H, Hollinshead F, Sieme H.The aim of this double-blinded placebo-controlled study was to investigate the effect of acetylsalicylic acid (ASA) on uterine blood flow, gestation length, placental and foal weights in pregnant mares. Sixteen Thoroughbred mares of different age (13.3 ± 4.1) and parity (7.4 ± 3.1) were randomly assigned to three treatment groups. Mares in group C (n = 4) served as controls and received 5,000 mg lactose orally once daily from D 120 (D 0 = day of ovulation) until parturition. Mares in group ASA1 (n = 7) received 5,000 mg ASA orally once daily from D 120 until parturition. Mares in group...
Orsolini MF, Verstraete MH, van Heule M, Orellana D, Ortega A, Meyers S, Dini P.Intracytoplasmic sperm injection (ICSI) is the only method for in vitro embryo production (IVP) in horses. Besides oocyte developmental competence, the outcome of IVP is also highly dependent on sperm quality. Therefore, it is not only essential to employ superior methods of selecting high quality sperm, but also to be able to characterize which quantifiable properties of sperm quality are most indicative of its fertility. In men, a net negative surface charge, estimated by zeta potential (ZP) is highly correlated with sperm quality and in vitro embryo developmental outcomes. However, there ...
Mouncey R, Arango-Sabogal JC, de Mestre A, Verheyen K.The study aimed to (1) describe the use of reproductive therapeutics; (2) estimate the incidence of disease and injury; and (3) describe non-reproductive medications administered during pregnancy in Thoroughbred broodmares. A prospective birth cohort was established on seven farms across the UK and Ireland. Details of dams' signalment, breeding history, reproductive management during the breeding season(s) and veterinary-attended episodes of illness or injury and medication usage during gestation were retrieved retrospectively for 275 pregnancies in 235 mares over two breeding seasons. Results...
Houben RMAC, van Maanen K, Kemp-Symonds JG, Waller AS, Sloet van Oldruitenborgh-Oosterbaan MM, Heesterbeek H.Streptococcus equi spp. equi (S. equi), the cause of strangles in horses, is considered a highly contagious pathogen affecting equines and the equine industry worldwide. Fundamental epidemiological characteristics of outbreaks, such as the basic reproduction number (R ), are not well described. Objective: Estimate R for S. equi in equine populations from outbreak data. Methods: Systematic review and meta-analysis of published and unpublished data. Methods: A literature search for outbreak reports was carried out. Depending on data available in the reports, the early epidemic growth rate or fin...
Oquendo PS, Silva ESM, Oquendo FMG, Cuervo-Arango J, Beletti ME.The effect of three different hormonal protocols to prepare anestrous recipient mares on embryo survival was evaluated. The first group consisted of only progesterone administration (NE) 4 days before embryo transfer, while the recipients from the other two groups received a single administration of 2.5 mg of oestradiol benzoate (SE) 2 days earlier or 8 mg of oestradiol split in increasing doses for 5 consecutive days (LE) ending 3 days before progesterone treatment. The likelihood of recovering an embryo 2 days after transfer was 46.1% (6/13), 62.5% (5/8) and 85.7% (6/7) for recipie...
Stonehouse O, Stefanovski D, Bowman B, Sertich PL, Demchur J, Lewis GM, Turner RM, Turner RMO.Nocardioform placentitis (NP) has been associated with mid to late pregnancy loss in mares. To date, disease outbreaks have been described only in central Kentucky, although sporadic, isolated cases have been reported globally. This study describes a series of cases of NP that occurred in a sample population of 299 mares foaling in southeastern Pennsylvania and northeastern Maryland in 2020. These cases coincided with an outbreak of NP that occurred in Kentucky that same year. On farms that reported information on both normal and abnormal foalings, nocardioform organisms/DNA were isolated from...
Shen Y, Ren H, Davshilt T, Tian S, Wang X, Yi M, Ulaangerel T, Li B, Dugarjav M, Bou G.During equine early gestation, trophectoderm forms chorion tissue, which is composed of two parts that one is covering allantoin, called allantochorion (AC) and another is covering yolk sac, which here we call vitelline-chorion (VC). Given that little is known about the equine trophoblast-derived chorion differentiation at an early stage, we first compared the transcriptome of AC and VC of day 30 equine conceptus based on RNA-sequencing. As a result, we found that compared to VC, there are 484 DEGs, including 305 up- and 179 down-regulated genes in AC. GO and KEGG analysis indicated that up-re...
El-Sheikh Ali H, Scoggin K, Murase H, Norris J, Menarim B, Dini P, Ball B.The equine chorioallantois (CA) undergoes complex physical and biochemical changes during labor. However, the molecular mechanisms controlling these changes are still unclear. Therefore, the current study aimed to characterize the transcriptome of equine CA during spontaneous labor and compare it with that of normal preterm CA. Placental samples were collected postpartum from mares with normal term labor (TL group, n = 4) and from preterm not in labor mares (330 days GA; PTNL group, n = 4). Our study identified 4137 differentially expressed genes (1820 upregulated and 2317 downregulat...
Li J, Zhu Y, Mi J, Zhao Y, Holyoak GR, Yi Z, Wu R, Wang Z, Zeng S.Endometrial and vaginal microbiomes are critical in the study of endometritis, which is an important cause of infertility in donkeys. Our objective was to investigate the difference of the endometrial and vaginal microbiomes between healthy donkey jennies (group C) and jennies with endometritis (group E). Endometrial and vaginal swab samples were collected, and the 16 s rRNA gene amplicon high-throughput sequencing technique was applied to identify the microbial composition in the samples. A similar microbial composition pattern was found between endometrial and vaginal samples, which indica...
Cappelli K, Ciucis CG, Mecocci S, Nervo T, Crescio MI, Pepe M, Gialletti R, Pietrucci D, Migone LF, Turco S, Mechelli L, Passamonti F, Drago C....Equine Papillomavirus 2 (EcPV2) is responsible for squamous cell carcinomas (eSCCs) of external genitalia of both male and female horses. However, few studies report the EcPV2 prevalence among healthy horses. Currently, the lack of these data does not permit identifying at-risk populations and, thus, developing screening protocols aimed at the early detection of the infection, as for humans. The aim of our study was to estimate the genoprevalence of EcPV2 in clinically healthy horses in Italy and to evaluate their innate immune response. For this purpose, penile and vulvar swabs of 234 healthy...
Wobbe M, Reinhardt F, Reents R, Tetens J, Stock KF.Awareness of breeders of Warmblood Fragile Foal Syndrome (WFFS) increased after a widely discussed case in the USA in 2018. The hereditary connective tissue disorder, first described by a US research group in 2011 and for which a commercial genetic test exists since 2013, is caused by a point mutation in the PLOD1 gene, inherited autosomal recessively. Extension of molecular genetic testing and reporting of test results of organized horse breeders to their studbooks implies new opportunities for analyses. In Germany, data are centrally accessible through the integrated equine data base allowin...
Koroleva E, Steffen HC, Bosch C, Flemming L, Botha A.Increasing cases of equine infertility and early embryonic loss in the Western Cape, South Africa, were documented in recent years. These appeared to be associated with Corynebacterium uterequi isolated from the uteri of infected mares. The purpose of this study was, therefore, to investigate the physiology and potential pathogenicity of this bacterium. Histopathological analyses were conducted on five mares suffering from reproductive complications, and from which Corynebacterium strains were detected on culture of uterine swabs. The histopathology revealed that the mares suffered from variou...
Walbornn SR, Felix M, Schnobrich MR, Bradecamp EA, Scoggin CF, Stefanovski D, Hinrichs K.To determine the effect of stage of estrus cycle (day after ovulation) at the time of transvaginal ultrasound-guided follicle aspiration (TVA) on parameters related to the success of in vitro equine embryo production. 14 healthy mares were used; 11 completed the study and were included for analysis. Mares underwent TVA of all follicles ≥ 5 mm diameter at each of 3 timepoints: 7 days after ovulation, 14 days after ovulation, and S-DSF (subordinate to a dominant stimulated follicle), during estrus at 24 hours after gonadotropin administration. The 3 treatments were assigned to each mare in ran...
Alpoim-Moreira J, Fernandes C, Rebordão MR, Costa AL, Bliebernicht M, Nunes T, Szóstek-Mioduchowska A, Skarzynski DJ, Ferreira-Dias G.Collagen pathological deposition in equine endometrium (endometrosis) is responsible for infertility. Kenney and Doig's endometrial biopsy histopathological classification is the gold standard method for endometrosis evaluation, whereby blood biomarkers identification would be less invasive and could provide additional information regarding endometrosis diagnosis and fertility prognosis. This study aimed to identify blood biomarkers for endometrosis diagnosis (42 mares were used in experiment 1), and fertility assessment (50 mares were used in experiment 2). Reproductive examination, endometri...
Inoue S.Maternal aging has negative influences on the development and racing performance of their offspring in racehorses. However, the mechanism by which pregnancy at old age reduces the race performance of the offspring is unknown. Here, two hypotheses were posited: 1) Foals born to older mares are more likely to have muscular, skeletal, and cognitive disadvantages (direct effects). 2) Foals born to older mares are more likely to be affected by non-physiological factors correlating with the mare's age, such as the quality of sires (e.g. low-quality sires are likely to be chosen as partners of older ...
Salem SE, Sinnott A, Roach JM, Verheyen KLP, de Mestre AM.Multiple pregnancies (MPs) are commonly diagnosed during breeding management of mares. Whilst some studies have reported on factors associated with the risk of MPs, few have utilised multivariable data analysis to control for confounding variables. A prospective cohort study of Thoroughbred broodmares was conducted with information collected on 27 factors. Mixed-effects logistic regression was used to determine risk factors for MPs. Mare, stallion, stud, and veterinarian were evaluated as random effects. The prevalence of MPs in 1754 mares and 2245 pregnancies was 16.06% (95% confidence interv...
Müller A, Glüge S, Vidondo B, Wróbel A, Ott T, Sieme H, Burger D.Prediction of impending foaling is highly desirable as early intervention may improve mare and foal outcomes. However, monitoring the peripartum mare is a time-consuming challenge for breeders and many foaling prediction systems have limitations. "Heating up" of the mare is empirically used by breeders as a sign of upcoming parturition in mares. The purpose of this study was to investigate if an increase in skin temperature shortly before parturition is detectable and to determine whether such physiological changes could be an additional valuable parameter to predict foaling. For that, 56 foal...
Handschuh S, Okada CTC, Walter I, Aurich C, Glösmann M.Here, we describe a workflow for high-detail microCT imaging of formalin-fixed and paraffin-embedded (FFPE) equine embryos recovered on Day 34 of pregnancy (E34), a period just before placenta formation. The presented imaging methods are suitable for large animals' embryos with intention to study morphological and developmental aspects, but more generally can be adopted for all kinds of FFPE tissue specimens. Microscopic 3D imaging techniques such as microCT are important tools for detecting and studying normal embryogenesis and developmental disorders. To date, microCT imaging of vertebrate e...
Ortega-Ferrusola C, Gómez-Arrones V, Martín-Cano FE, Gil MC, Peña FJ, Gaitskell-Phillips G, Da Silva-Álvarez E.Ultrasound technology has led to new lines of research in equine reproduction, and it has helped to greatly improve clinical diagnosis and reproductive outcomes in equine practice. This review aims to discuss the potential clinical uses and new approaches of ultrasonography in equine reproduction. Doppler modalities are usually used to evaluate the vascularization of the follicles, corpus luteum (CL), and the uterus in the mare for diagnostic purposes. Inclusion of Doppler ultrasound in artificial insemination and embryo transfer programs could improve the reproductive outcome of these techniq...
Podico G, Canisso IF.This study aimed to assess the parameters of epididymal sperm harvested by retrograde flushing (RF) followed by slicing float-up (SF). Epididymides from donkeys (n = 18) and horses (n = 28) were subjected to RF with a freezing extender and then SF technique. The retrieved sperm after RF and SF was evaluated for volume, concentration, and total sperm and then cryopreserved separately. Post-thaw total motility (TM) and progressive motility (PM) were evaluated with CASA. Sperm membrane integrity (SMI) and mitochondrial membrane potential (MMP) were assessed with flow cytometry. Sperm concentratio...
Zhang FL, Zhang XY, Zhao JX, Zhu KX, Liu SQ, Zhang T, Sun YJ, Wang JJ, Shen W.Mongolian horses have been bred and used for labor and transport for centuries. Nevertheless, traits of testicular development in Mongolian horses have rarely been studied; particularly, studies regarding the transcriptional regulation characteristics of testicular development are lacking. In this paper, transcription specificity during testicular development in Mongolian horses is highlighted via a multispecies comparative analysis and weighted gene co-expression network analysis (WGCNA). Interestingly, the results showed that most genes were up-regulated in the testes after sexual maturity, ...
Fabová Z, Tarko A, Harrath AH, Alwasel S, Kotwica J, Sirotkin AV.Influence of oil-related product toluene and herbal remedy puncturevine Tribulus terrestris L. (TT) on female reproduction is known. Yet, mechanisms of their action on ovaries in different species and potential protective effect of TT against adverse toluene action remain to be established. We studied the effect of toluene, TT, and their combination on ovarian granulosa cells from two mammalian species (cows and horses). Viability, markers of proliferation (PCNA) and apoptosis (bax), steroid hormones, IGF-I, oxytocin, and prostaglandin F (PGF) release were analyzed by trypan blue exclusion tes...
Alves KA, Alves BG, Gastal GD, de Tarso SG, Gastal MO, Figueiredo JR, Gambarini ML, Gastal EL.Ovarian tissue collected by biopsy procedures allows the performance of many studies with clinical applications in the field of female fertility preservation. The aim of the present study was to investigate the influence of reproductive phase (anestrous vs. diestrous) and ovarian structures (antral follicles and corpus luteum) on the quality, class distribution, number, and density of preantral follicles, and stromal cell density. Ovarian fragments were harvested by biopsy pick-up procedures from mares and submitted to histological analysis. The mean preantral follicle and ovarian stromal cell...
Christoffersen M, Woodward EM, Bojesen AM, Petersen MR, Squires EL, Lehn-Jensen H, Troedsson MH.The objective of the present study was to evaluate the effect of immunomodulatory therapy (glucocorticoids (GC) and mycobacterium cell wall extract (MCWE)) on the endometrial gene expression of inflammatory cytokines in susceptible mares with induced infectious endometritis. Endometrial gene expression of pro- and anti-inflammatory cytokines; interleukin (IL)-1β, IL-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, IL-1 receptor antagonist (ra), acute phase protein (APP) serum amyloid A (SAA) and clinical parameters were evaluated. Five mares were classified as susceptible to persistent endomet...
Torner H, Alm H, Kanitz W, Goellnitz K, Becker F, Poehland R, Bruessow KP, Tuchscherer A.The aim of this investigation was to examine the chromatin configuration of the nucleus, pattern of mitochondrial aggregation and mitochondrial activity in parallel studies in the same horse oocytes. Horse oocytes recovered by ultrasound-guided follicle aspiration in vivo were classified according to two main initial cumulus morphologies as having compact or expanded cumulus. The percentage of oocytes with a diplotene meiotic configuration at the time of recovery from the follicles was highest in compact oocytes. Oocytes with expanded cumulus layers at the time of recovery matured more rapidly...
BMC research notesApril 12, 2011
Volume 4 120 doi: 10.1186/1756-0500-4-120
Klein C, Rutllant J, Troedsson MH.Quantitative RT-PCR data are commonly normalized using a reference gene. A reference gene is a transcript which expression does not differ in the tissue of interest independent of the experimental condition. The objective of this study was to evaluate the stability of mRNA expression levels of putative reference genes in three different types of equine tissue, endometrial, testicular, and conceptus tissue. Results: The expression stability of four (uterine tissue) and six (testicular and conceptus tissue) was assessed using descriptive data analysis and the software programs Normfinder and geN...
Del Piero F.Equine viral arteritis (EVA) can cause prominent economic losses for the equine industry. The purpose of this review is to provide the pathologist some familiarity with the clinical history, lesions, pathogenesis, and diagnosis of EVA. EVA is caused by an arterivirus (equine arteritis virus, EAV), and the vascular system is the principal but not unique viral target. EVA has variable presentations, including interstitial pneumonia, panvasculitis with edema, thrombosis and hemorrhage, lymphoid necrosis, renal tubular necrosis, abortion, and inflammation of male accessory genital glands. EAV anti...
Caillaud M, Duchamp G, Gérard N.A growing body of evidence suggests that the interleukin-1 system is involved in periovulatory events. Previous work from our lab demonstrated that in the mare, interleukin-1beta (IL-1beta) increases the ovulatory rate of metaphase II oocytes. The present study was conducted to analyze in vivo the effect of IL-1 on oocyte cytoplasmic maturation, ovulation and pregnancy rate. In the present work, IL-1beta (experiment 1, n = 13; experiment 2, n = 25) and interleukin-1RA (IL-1RA; experiment 1, n = 25) were injected intrafollicularly by using the transvaginal ultrasound-guided injection method. In...
Ball BA, Medina V, Gravance CG, Baumbe J.Preservation of liquid semen at 5 degrees C is an important technique in the breeding management of horses. Oxidative damage to spermatozoa during storage is a potential cause of the decline in motility and fertility during hypothermic storage of liquid semen. The objective of this study was to evaluate the use of water-soluble and lipid-soluble antioxidants to improve the maintenance of motility of equine spermatozoa at 5 degrees C during storage for 72 to 96 h. In Experiment 1, the effect of addition of catalase on the maintenance of motility, viability and acrosomal integrity was determined...
Giontella A, Sarti FM, Cardinali I, Giovannini S, Cherchi R, Lancioni H, Silvestrelli M, Pieramati C.The Sardinian Anglo Arab (SAA) is a famous horse breed in Italy, with a significant historical background in the island of Sardinia. The aim of the study is to perform an evaluation of genetic variability in SAA using pedigree and mitochondrial data. In the current population, pedigree completeness was observed to be close to 100%, while the inbreeding coefficient and the average relatedness were lower than 3%. The ratio of effective founders/numbers of ancestors was 3.68 for the whole pedigree. The effective population size (N) computed by an individual increase in inbreeding (N) was 456.86, ...
Walsh CM, Prendergast RL, Sheridan JT, Murphy BA.The production of melatonin during night-time hours decodes day length for seasonally breeding animals. The use of artificial light to advance the breeding season in mares is common practice within the equine industry. Four healthy Thoroughbred mares were used to evaluate the minimum intensity of light required to inhibit serum melatonin. Mares were fitted with indwelling jugular catheters and using a crossover design blood samples were collected following 1h exposure to light (barn lighting approximately 200 lux), dark (<0.1 lux), and 3, 10, 50, and 100 lux intensities. The light source wa...
Claes A, Stout TAE.In vitro embryo production (IVEP) via Ovum Pick-Up (OPU) and Intracytoplasmic Sperm Injection (ICSI) has become a popular breeding technique in Warmblood mares because of the high success rate and several practical advantages. IVEP offers a solution for a variety of reproductive issues including, but not limited to, sub-fertility in stallions or mares, poor quality or scarce frozen semen, difficulty in synchronizing donor and recipient mares, and inefficient use of recipient mares. In 515 OPU-ICSI sessions performed in our facility in 2021, a mean of 25.9 antral follicles were aspirated yield...
Jacobson CC, Choi YH, Hayden SS, Hinrichs K.Oocytes may be collected from live mares from either the stimulated preovulatory follicle or from all visible immature follicles. We evaluated the yield of mature oocytes, and of blastocysts after intracytoplasmic sperm injection (ICSI), for both follicle types. In Experiment 1, mares were assigned to Progesterone (1.2g biorelease progesterone weekly) or Control treatments. Transvaginal aspiration of all follicles was performed every 14 d. Overall, 596 follicles were aspirated, with a 54% oocyte recovery rate. There was no difference between treatments in number of follicles punctured (9.0 to ...
Alvarenga MA, Papa FO, Landim-Alvarenga FC, Medeiros AS.Stallion semen cryopreservation, despite its impact on the horse industry, is not an established technology. During the last years, a number of modifications have been proposed to the freezing process, however, a large population of stallions still have poor semen quality and fertility after frozen-thawed. Glycerol toxicity could be a reason for the variation on stallion sperm freezability. There are limited publications concerning the use of alternative cryoprotectants for equine sperm. Glycerol is contraceptive for some species and other cryoprotectors, such as amides, have been show to be a...
Ginther OJ.The nature of selection of the dominant follicle is reviewed by comparing research results between cattle and horses. In both species, emergence of a follicular wave is stimulated by an FSH surge. The surge reaches a peak by the time the follicles attain 4 mm in diameter in cattle and 13 mm in mares. In cattle, all of the growing follicles >/=5 mm contribute to the decline in FSH concentrations. However, the declining FSH concentrations are still needed by the growing follicles. Several days after the peak of the FSH surge and emergence of the wave, the two largest follicles reach means of 8.5...
Ortega-Ferrusola C, Gracia-Calvo LA, Ezquerra J, Pena FJ.Doppler ultrasonography is an important tool in the andrological evaluation in humans; however, this method is not so extensively used by equine andrologists. Spectral or pulse Doppler is a useful non-invasive method for the early diagnosis of subfertility problems in the male, especially those triggered by vascular disturbance. The identification of any disturbance in the blood flow of the testis is crucial for a correct diagnosis of various testicular and scrotal disorders but also to monitor the therapeutic outcome following treatment. The aim of this review is to provide an update on the c...
McCabe L, Griffin LD, Kinzer A, Chandler M, Beckwith JB, McCabe ER.The lethal white foal syndrome (LWFS) is a congenital abnormality of overo spotted horses which is a model for human aganglionic megacolon or Hirschsprung disease. Foals with LWFS have an all white, or nearly all white, coat. They also present clinically with an intestinal obstruction that proves fatal within the first few days of life. The LWFS involves both melanocytes and intestinal ganglion cells, and appears to result from a genetic defect involving neural crest cells. This report describes pathologic studies of two recent cases of LWFS. Two different hypothetical models of inheritance of...
Nash DM, Sheldon IM, Herath S, Lane EA.Reproductive efficiency in mares is low and persistent mating-induced endometritis (PMIE) is an important cause of subfertility. Mating-induced endometritis (MIE) an obligate precursor to PMIE, is a ubiquitous, transient inflammatory response to the presence of sperm, seminal components and pathogens. However, the specific inflammatory pathways that derive from MIE and that may also be precursors to PMIE are not clear. The ability to identify and measure robust, repeatable markers of inflammation integral to MIE may be key to understanding the progression to PMIE. The aim of the study was to (...
Miró J, Marín H, Catalán J, Papas M, Gacem S, Yeste M.In the donkey, artificial insemination (AI) with frozen-thawed semen is associated with low fertility rates, which could be partially augmented through adding seminal plasma (SP) and increasing sperm concentration. On the other hand, post-AI endometrial inflammation in the jenny is significantly higher than in the mare. While previous studies analyzed this response through recovering Polymorphonuclear Neutrophils (PMN) from uterine washings, successive lavages can detrimentally impact the endometrium, leading to fertility issues. For this reason, the first set of experiments in this work inten...
Dunowska M.Equid herpesvirus (EHV) type 1 is a common pathogen of horses with worldwide distribution. Although severe tracheobronchitis has been described in some field outbreaks of EHV-1 respiratory disease, many EHV-1 infections occur asymptomatically or are accompanied only by signs of mild respiratory disease. However, EHV-1 infection can also result in outcomes other than respiratory disease such as abortion, neonatal death or neurological disease. This review provides an overview of the diagnosis, treatment and prognosis for EHV-1-associated diseases, with an emphasis on neurological presentations ...
Del Piero F.Equine viral arteritis (EVA) can cause prominent economic losses for the equine industry. The purpose of this review is to provide the pathologist some familiarity with the clinical history, lesions, pathogenesis, and diagnosis of EVA. EVA is caused by an arterivirus (equine arteritis virus, EAV), and the vascular system is the principal but not unique viral target. EVA has variable presentations, including interstitial pneumonia, panvasculitis with edema, thrombosis and hemorrhage, lymphoid necrosis, renal tubular necrosis, abortion, and inflammation of male accessory genital glands. EAV anti...
Bonilla-Correal S, Noto F, Garcia-Bonavila E, Rodríguez-Gil JE, Yeste M, Miro J.Aquaporins (AQPs) are transmembrane proteins found in all cells and are responsible for the transport of water and small solutes. While these proteins have been found in the spermatozoa of humans, rodents, pigs and cattle, where not only do they play a role for the regulation of sperm volume but are also related with the sperm resilience to withstand freeze-thawing procedures, their presence in stallion sperm is yet to be reported. Therefore, the objectives of this work were as follows: (i) to determine whether AQP3, AQP7 and AQP11 are present in stallion sperm and (ii) to investigate whether ...
Sandra O, Charpigny G, Galio L, Hue I.In mammalian species, endometrial receptivity is driven by maternal factors independently of embryo signals. When pregnancy initiates, paracrine secretions of the preattachment embryo are essential both for maternal recognition and endometrium preparation for implantation and for coordinating development of embryonic and extraembryonic tissues of the conceptus. This review mainly focuses on domestic large animal species. We first illustrate the major steps of preattachment embryo development, including elongation in bovine, ovine, porcine, and equine species. We next highlight conceptus secret...
Causey RC.Equine uterine infections inflict major losses on the equine industry. Persistent inflammation of the oviduct and uterus leads to loss of the conceptus and mares susceptible to infection have weakened uterine defences partly due to retention of inflammatory exudate. Bacteria may trigger inflammation, resist phagocytosis, or adhere to the endometrium and types of infection range from genital commensals in susceptible mares to reproductive pathogens in normal mares. Uterine infections are diagnosed by history, detection of uterine inflammation, and isolation of typical organisms and susceptible ...
Gozalo-Marcilla M, Bettschart-Wolfensberger R, Johnston M, Taylor PM, Redondo JI.It is almost 20 years since the largest observational, multicentre study evaluating the risks of mortality associated with general anaesthesia in horses. We proposed an internet-based method to collect data (cleaned and analysed with R) in a multicentre, cohort, observational, analytical, longitudinal and prospective study to evaluate peri-operative equine mortality. The objective was to report the usefulness of the method, illustrated with the preliminary data, including outcomes for horses seven days after undergoing general anaesthesia and certain procedures using standing sedation. Within ...
Woodward EM, Troedsson MH.Transient post breeding endometritis is a normal physiological reaction in the mare, as it is believed that an inflammatory response is necessary for the effective removal of contaminating bacteria and excess spermatozoa introduced into the uterus. While most mares can clear endometritis within a reasonable amount of time, persistent endometritis caused by either bacteria or spermatozoa can threaten the success of a pregnancy. A subpopulation of mares is susceptible to persistent endometritis, and these mares are a concern in equine reproductive medicine. Research has identified several factor...
Ginther OJ.The mare is a good comparative model for study of ovarian follicles in women, owing to striking similarities in follicular waves and the mechanism for selection of a dominant follicle. Commonality in follicle dynamics between mares and women include: (1) a ratio of 2.2:1 (mare:woman) in diameter of the largest follicle at wave emergence when the wave-stimulating FSH surge reaches maximum, in diameter increase of the two largest follicles between emergence and the beginning of deviation between the future dominant and subordinate follicles, in diameter of each of the two largest follicles at th...
Nuñez CM, Adelman JS, Rubenstein DI.Although the physiological effects of immunocontraceptive treatment with porcine zona pellucida (PZP) have been well studied, little is known about PZP's effects on the scheduling of reproductive cycling. Recent behavioral research has suggested that recipients of PZP extend the receptive breeding period into what is normally the non-breeding season. Results: To determine if this is the case, we compiled foaling data from wild horses (Equus caballus) living on Shackleford Banks, North Carolina for 4 years pre- and 8 years post-contraception management with PZP (pre-contraception, n = 65 births...
Meijer MC, van Weeren PR, Rijkenhuizen AB.The condition of septic arthritis was treated in 12 foals with 21 affected joints (Group I) and in 27 adult horses. The adult horses were divided into three groups, based on aetiology of the condition: haematogenous (Group II, n = 6), iatrogenic (Group III, n = 6), and perforating trauma (Group IV, n = 15). The treatment consisted of an initial systemic antibiotic that anticipated the microbial agents that were considered most likely per group, repeated through-and-through joint lavages every other day and non-steroidal anti-inflammatory drugs. The antibiotics were adjusted to the results of b...
Aurich C, Budik S.Early equine pregnancy shares many features with that of more intensively assessed domestic animals species, but there are also characteristic differences. Some of those are poorly understood. Descent of the equine conceptus into the uterine lumen occurs at day 5 to 6 after ovulation but is only possible when the embryo secretes prostaglandin E2. Although maintenance of equine pregnancy probably involves secretion of a conceptus derived anti-luteolytic factor, this agent has not been identified. Rapid growth, conceptus mobility and presence of an acellular capsule at the time of maternal recog...
Natali AN, Carniel EL, Frigo A, Pavan PG, Todros S, Pachera P, Fontanella CG, Rubini A, Cavicchioli L, Avital Y, De Benedictis GM.What is the central question of this study? Prostheses for treatment of urinary incontinence elicit complications associated with an inadequate mechanical action. This investigation aimed to define a procedure addressed to urethral mechanical characterization. Experimental tests are the basis for constitutive formulation, with a view to numerical modelling for investigation of the interaction between the tissues and a prosthesis. What is the main finding and its importance? Horse urethra, selected for its histomorphometric similarity to human urethra, was characterized by integrated histologic...
Glazar AI, Mullen SF, Liu J, Benson JD, Critser JK, Squires EL, Graham JK.Stallion spermatozoa exhibit osmotic damage during the cryopreservation process. Recent studies have shown that the addition of cholesterol to spermatozoal membranes increases the cryosurvival of bull, ram and stallion spermatozoa, but the exact mechanism by which added cholesterol improves cryosurvival is not understood. The objectives of this study were to determine if adding cholesterol to stallion sperm membranes alters the osmotic tolerance limits and membrane permeability characteristics of the spermatozoa. In experiment one, stallion spermatozoa were treated with cholesterol-loaded cycl...
