Mares and horses are integral components of equine studies, focusing on the reproductive and behavioral aspects of equine biology. Mares, or adult female horses, play a significant role in breeding programs and are often studied for their reproductive physiology, gestation, and maternal behaviors. Horses, as a broader category, encompass both sexes and all age groups, providing a comprehensive view of equine anatomy, physiology, and behavior. Research in this area often investigates the differences and similarities between mares and other horses in terms of hormonal cycles, reproductive health, and social interactions. This page compiles peer-reviewed studies and scholarly articles that explore the biological and behavioral characteristics of mares and horses, offering insights into their roles in equine science and management.
Nielsen MK, Littman BA, Orzech SW, Ripley NE.Equine cyathostomins are ubiquitous in grazing horses around the world and a main target in parasite control programs. Anthelmintic resistance has been reported with increasing frequency in these parasites over the past decades, and recent findings of fulminant resistance to the macrocyclic lactone class have raised severe concerns. This study aimed to evaluate ivermectin efficacy in cohorts of yearlings and mares present on four different farms in Central Kentucky. Strongylid egg counts were determined with an automated egg counting system, and the percent fecal egg count reduction (FECR) was...
Knott LE, Fonseca-Martinez BA, O'Connor AM, Goodrich LR, McIlwraith CW, Colbath AC.To evaluate the use of mesenchymal stem cells (MSCs), autologous conditioned serum (ACS), platelet-rich plasma (PRP), and autologous protein solution (APS) for the treatment of equine musculoskeletal disease by diplomates of the American College of Veterinary Surgery (ACVS), and American College of Veterinary Sports Medicine and Rehabilitation (ACVSMR). Methods: Cross-sectional study. Methods: Diplomates (n = 423). Methods: An email link was sent to ACVS and ACVMR diplomates. A survey contained 59 questions regarding demographics, as well as indications, frequency, adverse effects, and limit...
Hyde KA, Aguiar FLN, Alves BG, Alves KA, Gastal GDA, Gastal MO, Gastal EL.Characterization of the ovarian preantral follicle population is a necessary step to improve understanding of folliculogenesis and ovarian physiology. Therefore, in the present study, the preantral follicle population in the equine ovary in young and old mares was investigated according to follicular morphology, follicular class, distance from the geometric center using ovarian maps, and follicular density within ovarian portions (lateral vs intermediary) and regions (dorsal vs ventral). Ovaries were collected from an abattoir and histologically processed for evaluation, and the follicle popul...
Renaudin CD, Kass PH, Bruyas JF.A table was generated, based on foetal ultrasonographic measurements in light breed mares, for each day of gestation beginning with day 100, to provide the predicted value of four biometric parameters: biparietal diameter (BPD), eye approximated volume (EyV), foetal aortic diameter (AortD) and femur length (FL). Using this table, day of gestation was successfully predicted in 23 Quarter Horses (QH) with known mating or ovulation dates. BPD, EyV and FL were the best foetal age predictors between 100- and 200-days gestation predicting within 2 weeks of the actual day of gestation, while BPD and...
Stasiak K, Dunowska M, Rola J.Equid herpesvirus 2 (EHV-2) and 5 (EHV-5) are two γ-herpesviruses that are commonly detected from horses worldwide, based on several cross-sectional molecular surveys. Comparatively few studies examined the dynamics of γ-herpesvirus infection over time in a group of horses. The aim of the current study was to investigate the dynamics of EHV-2/5 infections among mares and their foals at three Polish national studs with different breeds of horses: Arabians, Thoroughbreds and Polish Konik horses. Nasal swabs were collected from each of 38 mare-foal pairs monthly for a period of 6 to 8 months. V...
Kaps M, Lutzer A, Gautier C, Nagel C, Aurich J, Aurich C.Horse mares are frequently treated with the progestin altrenogest with the aim to suppress estrous behavior and its negative impact on equestrian performance. Progestogens, however, also have sedative effects in males, and females of different species. The aim of our study was therefore to investigate altrenogest-induced changes in the stress response of female horses during initial equestrian training. Three-yr-old Warmblood mares were randomly assigned to treatment with altrenogest (ALT; 0.044 mg/kg once daily; n = 6) or sunflower oil (CON; n = 5) for 12 wk during training. At predefined...
Spencer KM, Podico G, Megahed AA, Jones KL, Bittar JHJ, Canisso IF.This study aimed to assess the ovulatory response of deslorelin acetate during the fall and the response to PGF2α 8 d post-ovulation. One hundred estrous cycles from 22 mares kept in 40° latitude were evaluated. Mares were checked by transrectal ultrasonography until a preovulatory follicle was detected and ovulation induced with deslorelin acetate. Ovulation was confirmed by ultrasonography performed at 24, 36 h post-induction and then repeated at 2-h intervals post-induction. Serum progesterone concentrations and luteal tissue area were determined daily to assess CL function. A dose of P...
Donatsch L, Friker B, Sieme H, Kaeser R, Burger D.A potential source of fertility loss in mares is oviductal dysfunction, potentially caused by masses or debris in the lumen, that may prevent either sperm from reaching the fertilization site or the embryo from reaching the uterus. Recently a novel therapeutic method leading to increased pregnancy results was described by infusing misoprostol, a synthetic prostaglandin E, in the uterus of mares with unexplained fertility problems. In this study, we aimed, after examining the compatibility of misoprostol with semen, to evaluate the pregnancy rate after routine preovulatory deep uterine horn app...
Fanelli D, Tesi M, Monaco D, Diaz-Jimenez M, Camillo F, Rota A, Panzani D.In the literature, the very low pregnancy rates after artificial insemination (AI) with frozen semen in donkeys were improved in one study after re-extension of the frozen-thawed semen in autologous seminal plasma. The aims of our study were (1) to describe in vitro post-thaw parameters of donkey jackass semen after re-extension in seminal plasma (SP) or in INRA96 and (2) to compare pregnancy rates in jennies bred with frozen-thawed semen using two different AI protocols. Semen collected from two Amiata donkey stallions, known to be fertile, was frozen in INRA96 supplemented with 2% egg yolk, ...
Rampacci E, Mazzola K, Beccati F, Passamonti F.Feeding foals with poor quality colostrum predisposes them to failure of passive transfer (FPT). FPT is a major risk factor for neonatal infections. Objective: To assess the optimal cut-offs for the optical (OR) and digital (DR) refractometer and determine their accuracy for poor quality colostrum diagnosis. Methods: A diagnostic validation study. Methods: Eighty-one colostrum samples and sera were collected from broodmares and their neonatal foals, respectively. Colostral and serum IgG concentrations were measured by radial immunodiffusion (RID), DR and OR. Correlation coefficients were calcu...
Lutzer A, Nagel C, Aurich J, Murphy BA, Aurich C.In horses, blue LED light directed at one eye of pregnant mares shortens gestation length and results in the birth of foals with lower wither heights, similar weight and reduced hair length compared to controls. In this study, we have therefore analysed postnatal development of foals born to either blue LED light-treated (n = 20) or control mares (n = 20). Size, weight and hair coat changes were determined for 1 year and heart rate, heart rate variability (HRV) and selected haematology parameters for 1 month. Haematocrit decreased (P < .001) and leukocyte and lymphocyte counts increased...
Ginther OJ.Traveling of the fetal-amniotic unit throughout the uterus ceases on ∼ Day 180 followed by closure of each uterine horn. By mean Day 240, the fetus and nearly all of the pool of allantoic fluid are confined to the uterine body. Intrauterine fetal-location changes end, but in-place activity of limbs, head, and body and changes in fetal recumbency and presentation continue, sometimes vigorously. Preference for cranial presentation (fetal sternum toward maternal cervix) has been hypothesized to be stimulated by ∼ 40° incline of uterine body toward the cervix. The uterine body expands forward...
Derisoud E, Jouneau L, Margat A, Gourtay C, Dubois C, Archilla C, Jaszczyszyn Y, Dahirel M, Daniel N, Peynot N, Briot L, De Geoffroy F, Wimel L....No abstract available
Derisoud E, Auclair-Ronzaud J, Palmer E, Robles M, Chavatte-Palmer P.Although puberty can occur as early as 14-15months of age, depending on breed and use, the reproductive career of mares may continue to advanced ages. Once mares are used as broodmares, they will usually produce foals once a year until they become unfertile, and their productivity can be enhanced and/or prolonged through embryo technologies. There is a general consensus that old mares are less fertile, but maternal age and parity are confounding factors because nulliparous mares are usually younger and older mares are multiparous in most studies. This review shows that age critically affects c...
Tong P, Duan R, Palidan N, Deng H, Duan L, Ren M, Song X, Jia C, Tian S, Yang E, Kuang L, Xie J.EHV-1 is one of the most serious viral pathogens that frequently cause abortion in horses around the world. However, so far, relatively little information is available on EHV-1 infections as they occur in China. In January 2021, during an abortion storm which occurred in Yili horses at the Chinese State Studs of Zhaosu (North Xinjiang, China), 43 out of 800 pregnant mares aborted. Results: PCR detection revealed the presence of EHV-1 in all samples as the possible cause of all abortions, although EHV-4, EHV-2 and EHV-5 were also found to circulate in the aborted fetuses. Furthermore, the parti...
Jasiński T, Zdrojkowski Ł, Kautz E, Juszczuk-Kubiak E, Ferreira-Dias G, Domino M.Endometritis is an important issue decreasing mares' fertility. In the case of endometritis, both inflammatory cells infiltration and proinflammatory molecules production are regulated by various cellular and gene regulatory mechanisms, including the nuclear factor-κB (NF-κB)-dependent pathway. NF-κB-signalling pathway has been recently studied in the equine endometrium in the context of endometrosis. Thus, this study aimed to determine gene transcription of NF-κB subunits (RelA; NF-κB1; NF-κB2), proinflammatory molecules (MCP-1; IL-6) and hyaluronan synthases (HAS 1; HAS 2; HAS 3) in en...
Whitty JA, Miller AV, Miller AD, Carney PC, Scrivani PV.The styloid process sheath (SPS) is a part of the tympanic temporal bone and an incomplete bony sleeve surrounding the styloid process, tympanohyoid cartilage, and dorsal part of the stylohyoid bone. In horses undergoing head CT, we observed a range of SPS sizes and questioned whether differences were early features of temporohyoid osteoarthropathy (THO) or normal anatomic variations associated with age, body weight, sex, or breed. We hypothesized that SPS sizes were positively correlated with age and body weight, but not with sex or breed. Using a convenience population of horses that underwe...
Ravaioli V, Raffini E, Tamburini M, Galletti G, Frasnelli M.Endometritis is a major cause of infertility and subfertility in the mare. Early diagnosis and identification of the pathogens involved in infectious endometritis are crucial to initiate correct treatments in time, in order to optimize fertility and reduce the risk of bacterial resistance development. In this retrospective study (from 2014 to 2018), 394 samples (uterine swabs and lavages) obtained from mares before breeding, regardless of clinical history of endometritis were analyzed. Our bacteriological procedure included the subculturing from the enrichment in Brain Heart Infusion Broth of ...
Patterson Rosa L, Campos FA, Martin K, Vierra M, Foster G, Lundquist E, Brooks SA, Lafayette C.Pedigrees and horse written ancestry contain numerous inconsistencies and divergence between farm histories, owner accounts and registration records. In particular, the origins of the Brazilian Mangalarga, or "Mangalarga Paulista'' horse breed is controversial, and the breed's popular history claims that one of its most famous individuals, Turbante J.O., may have been sired by an unknown Hanoverian stallion. Turbante J.O. sired over 1678 offspring and is present in about 71% of the male pedigrees. We genotyped Turbante J.O. and 29 registered Mangalarga individuals using a commercially availabl...
Stelletta C, Alberti S, Cil B, Tekin K, Tirpan MB, Arganaraz M, Akcay E, Daskin A.The identification of various substances in seminal plasma has opened the way to study their functionality. It was aimed to identify the electrophoretic protein profile (EPP) and biochemical parameters (BP) of seminal plasma (SP) as predictors of semen quality and fertility in stallion. Forty-six ejaculates from 7 fertile stallions, aged between 6-26 years, were collected from May to July and 117 mares were used to obtain fertility data. For each ejaculate, volume, sperm motility, concentration were determined and seminal plasma samples were collected to perform one- -dimensional electrophores...
Lawson EF, Grupen CG, Baker MA, Aitken RJ, Swegen A, Pollard CL, Gibb Z.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. Recently, lipidomic technologies have advanced considerably and analytical strategies have been enhanced and diversified. Consequently, in-depth lipidomic exploration now has the potential to reveal new lipid biomarkers and biochemical relationships that im...
Ávila ACA, Diniz NC, Serpa RT, Chaves MMBC, Viu MAO, de Oliveira RA.Endometritis is defined as inflammation of the endometrium that may be acute or chronic, infectious, or non-infectious. Endometritis is an important cause of subfertility in mares. Considering the antimicrobial characteristics, immune-stimulating ability, and low cost of ozone (O3) therapy, we aimed to evaluate the effectiveness of intrauterine O3 therapy as an alternative treatment for endometritis in mares. Twenty-five mares with a known reproductive history of uterine infection and inflammation were allocated into three groups: Group 1 (control; n = 7), uterine lavage with Ringer's lactat...
Mainguy-Seers S, Diaw M, Lavoie JP.While the prevalence of asthma is higher in boys than in girls during childhood, this tendency reverses at puberty, suggesting an effect of sex hormones on the disease pathophysiology. Fluctuations of asthma severity concurring with the estrus cycle are reported in women, but this phenomenon has never been investigated in mares to date. The objective of this exploratory study was to determine whether the estrus cycle modulates airway obstruction in severe equine asthma (SEA). Five mares with SEA during exacerbation of the disease were studied. The whole breath, expiratory and inspiratory resis...
Laseca N, Molina A, Ramón M, Valera M, Azcona F, Encina A, Demyda-Peyrás S.The loss of genetic variability in livestock populations bred under strict selection processes is a growing concern, as it may lead to increased inbreeding values and lower fertility, as a consequence of the "inbreeding depression" effect. This is particularly important in horses, where inbreeding levels tend to rise as individuals become more and more closely related. In this study, we evaluated the effect of increased inbreeding levels on mare fertility by combining an SNP-based genomic approach using runs of homozygosity and the estimation of genetic breeding values for reproductive traits ...
Piotrowska-Tomala KK, Jonczyk AW, Szóstek-Mioduchowska AZ, Żebrowska E, Ferreira-Dias G, Skarzynski DJ.We examined the effect of prostaglandin (PG) E on the secretory function of equine corpus luteum (CL), according to the application site: intra-CL injection vs. an intrauterine (intra-U) administration. Moreover, the effect of intra-CL injection vs. intra-U administration of both luteotropic factors: PGE and human chorionic gonadotropin (hCG) as a positive control, on CL function was additionally compared. Mares were assigned to the groups ( = 6 per group): (1) an intra-CL saline injection (control); (2) an intra-CL injection of PGE (5 mg/ml); (3) an intra-CL injection of hCG (1,500 IU/ml); (4...
Szóstek-Mioduchowska AZ, Baclawska A, Okuda K, Skarzynski DJ.Equine endometrosis (endometrial fibrosis) is a degenerative chronic process that occurs in the uterus of the mare and disturbs proper endometrial function. Fibrosis is attributed to excessive deposition of extracellular matrix (ECM) components. The turnover of ECM is mediated by matrix metallopeptidases (MMP). Previously, it was shown that cytokines modulate MMP expression in other tissues and may regulate fibrosis indirectly by attracting inflammatory cells to the site of inflammation and directly on various tissues. However, the regulation of MMP expression in equine endometrosis is still r...
Hinrichs K, Schmidt AL.Horse oocytes were collected from an abattoir over a 15-mo period. After classification of follicle size and cumulus morphology, oocytes were either fixed immediately (0 h) or matured in vitro (24 h). There was no effect of season on the number of antral follicles present on the ovaries, or on oocyte maturation rate for any class of oocyte. The proportion of oocytes having condensed chromatin at 0 h increased with increasing follicle size. The oocyte maturation rate also increased with follicle size, and for follicles </= 20-mm diameter, was higher for oocytes initially having expanded cumu...
Flaminio MJ, Antczak DF.At days 36-38 of gestation, the equine invasive trophoblast cells migrate into the endometrium of the pregnant mare to form the endometrial cups. During their migration, they become surrounded by maternal CD4+ and CD8+ T lymphocytes, and stimulate a cytotoxic antibody response to the paternal major histocompatibility complex class I antigens that they express. Nevertheless, endometrial cup cells remain viable at the site of uterine invasion up to days 80-100 of gestation, suggesting the participation of immunomodulatory mechanisms to the maternal cellular immune response. To determine the effe...
Hendriks WK, Colleoni S, Galli C, Paris DB, Colenbrander B, Roelen BA, Stout TA.Advanced maternal age and in vitro embryo production (IVP) predispose to pregnancy loss in horses. We investigated whether mare age and IVP were associated with alterations in mitochondrial (mt) DNA copy number or function that could compromise oocyte and embryo development. Effects of mare age (<12 vs ≥12 years) on mtDNA copy number, ATP content and expression of genes involved in mitochondrial replication (mitochondrial transcription factor (TFAM), mtDNA polymerase γ subunit B (mtPOLB) and mitochondrial single-stranded DNA-binding protein (SSB)), energy production (ATP synthase-couplin...
Weber JA, Freeman DA, Vanderwall DK, Woods GL.The hypothesis that treatment of pregnant mares with prostaglandin E2 (PGE2) hastens the oviductal transport of equine embryos was tested by treating bred mares with PGE2 on Day 3 after ovulation and subsequently measuring the rate of hastened oviductal transport (estimated by the uterine embryo recovery rate on Day 4 after ovulation). In a preliminary, noncontrolled experiment, oviductal transport was apparently not hastened after intramuscular, intrauterine, or intraperitoneal PGE2 administration to bred mares (0/6, 0/3, and 0/3 mares, respectively). Oviductal transport appeared to be hasten...
DARLINGTON RW, RANDALL CC.Equine abortion virus was purified from the plasma of infected golden Syrian hamsters by differential centrifugation and nuclease treatment. The preparations were essentially free of nonviral elements on electron microscopic examination, and sedimentation in sucrose and potassium tartrate density gradients resulted in a single visible band. Electron microscopy of this band showed it to be composed of viral particles, and injection into hamsters resulted in infection and death of the animals. The viral particles had a sedimentation coefficient of approximately 2200 S and a hydrated density of 1...
Altermatt JL, Suh TK, Stokes JE, Carnevale EM.Young (4 to 9 yr) and old (>or=20 yr) mares were treated with equine follicle-stimulating hormone (eFSH), and oocytes were collected for intracytoplasmic sperm injections (ICSI). Objectives were to compare: (1) number, morphology and developmental potential of oocytes collected from young v. old mares from cycles with or without exogenous eFSH and (2) oocyte morphology parameters with developmental competence. Oocytes were collected from preovulatory follicles 20 to 24 h after administration of recombinant equine LH and imaged before ICSI for morphological measurements. After ICSI, embryo d...
Charlton KM, Mitchell D, Girard A, Corner AH.During an outbreak of abortion caused by equine herpesvirus 1, a neurologic disease characterized clinically by dullness and ataxia occurred in several mares. Equine herpesvirus 1 was isolated from brain and lung of two severely affected mares. Histologically, both mares had disseminated meningoencephalomyelitis characterized by necrotizing arteritis, focal malacia in grey and white matter of brain and spinal cord, and accumulation of lymphocytes and neutrophils in paravertebral ganglia. Eosinophilic intranuclear inclusion bodies occurred in foci of necrosis in thyroid adenomas of both mares.
Gildea S, Arkins S, Cullinane A.In Ireland, horses may be protected against equine influenza virus (EIV) as a result of natural exposure or vaccination. Current mandatory vaccination programmes are targeted at highly mobile horses. A correlation between antibody levels as measured by single radial haemolysis (SRH) and protective immunity against EIV has been established. Objective: The objective of this study was to determine the susceptibility of selected populations of horses by quantifying their antibodies to EIV. Methods: Blood samples were collected from Thoroughbred weanlings, yearlings, racehorses and broodmares, teas...
de Mestre AM, Rose BV, Chang YM, Wathes DC, Verheyen KLP.Early pregnancy loss (EPL) between days 15-65 after breeding has been shown to occur in 7.9% of equine pregnancies with substantial economical, welfare and safety implications. Whilst maternal age has been recognised as an important risk factor in relation to the incidence of EPL, few other risk factors have been conclusively identified. Further, multivariable data analysis of risk factors for EPL is sparse. A prospective cohort investigation of thoroughbred broodmares in the United Kingdom was conducted over the 2013 and 2014 breeding seasons. Information relating to 28 factors including mare...
Roberto da Costa RP, Ferreira-Dias G, Mateus L, Korzekwa A, Andronowska A, Platek R, Skarzynski DJ.Nitric oxide (NO) plays an important role in angiogenesis and in the regulation of the blood flow. This study was carried out to investigate (i) the effects of endogenous estrogens and progestins and exogenous progesterone (P(4)) (5 ng/ml or 1 microg/ml) or estradiol 17beta (E(2)beta) (50 pg/ml or 1 microg/ml) on in vitro endometrial NO synthesis; (ii) the presence of different isoforms of NO synthase; (iii) and their relationship to microvascular density in the equine endometrium during the estrous cycle. NOS expression was also evaluated in the myometrium. Expression of endothelial and induc...
Amaral A, Fernandes C, Lukasik K, Szóstek-Mioduchowska A, Baclawska A, Rebordão MR, Aguiar-Silva J, Pinto-Bravo P, Skarzynski DJ, Ferreira-Dias G.We have shown that bacteria induce neutrophil extracellular traps (NETs) in mare endometrium. Besides killing pathogens, NETs may contribute for endometrosis (chronic endometrium fibrosis). Since elastase (ELA) is a NETs component that regulates fibrosis and prostaglandin (PG) output, the aim was to evaluate if inhibition of ELA would affect collagen 1 (COL1) transcription and PGs secretion by endometrium explants, in different estrous cycle phases. Follicular-FP (n = 8) and mid luteal-MLP (n = 7) phases explants were cultured for 24-48 hr with medium alone (Control), ELA (0.5 μg/ml,1 ...
Duchamp G, Bour B, Combarnous Y, Palmer E.Injection of hCG (2000-2500 i.u., i.v.) to mares when a follicle reaches 35 mm induces ovulation between 24 and 48 h. However, repeated injections induce antibodies against hCG. We report attempts to induce ovulation without this inconvenience. We called 'response' an ovulation between 24 and 48 h after treatment. The typical response to hCG was obtained in 73% (N = 145) of treated mares. After immunization against hCG, the response (0%, N = 10) was less than in nonimmunized controls (100%, N = 9). Simultaneous injection of dexamethasone and hCG resulted in induction of ovulation (71%, N = 14)...
Holtan DW, Houghton E, Silver M, Fowden AL, Ousey J, Rossdale PD.This study used gas chromatography/mass spectrometry (GC/MS) to identify and measure plasma progestagens. The method included deuterated internal standards, e.g. [17,21,21,21-2H]-5 alpha-pregnane-3,20-dione, solid-phase extraction, derivatization (methoxime/t-butyldimethylsilyl) and GC/MS. Full-scan screening identified 3 5-pregnenes, 2 4-pregnenes and 7 5 alpha-pregnanes (no 5 beta-pregnanes). The selected ion mode was used for routine quantitation from calibration curves; response was linear (r greater than 0.98) from 2 to 2000 ng equivalents/ml (0.5 ng/ml method sensitivity) and intra- and ...
Silver IA, Brown PN, Goodship AE, Lanyon LE, McCullagh KG, Perry GC, Williams IF.This project was carried out over a five year period (1977 to 1981 inclusive) at the University of Bristol following discussion between the British Veterinary Association and the Royal College of Veterinary Surgeons about the efficacy of, and ethical justification for, the practice of 'firing' (cautery). These discussions had been promoted by parliamentary questions but led to no firm conclusions because previously reported clinical investigations on specific treatments lacked adequate comparisons and controls and thus did not provide scientifically acceptable, statistically valid data. The pr...
Kaseda Y, Khalil AM, Ogawa H.The stability of relationships between harem stallions and mares (consort relations) was investigated and the durations of inter partum intervals were determined in order to establish if there was any correlation between the stability of consort relation and reproductive success of mares in Misaki feral horses. Thirty-four mares were observed continuously for more than 5 years. The lifetime stability was 80-100% (mean 92.4%) for 16 mares, 60-79% (mean 70.4%) for 10 mares and 0-59% (mean 27.9%) for 8 mares. The continuous length (years) of specific consort relations was 2-10 years and was found...
Berghold P, Möstl E, Aurich C.Stressful events may contribute to low reproductive efficiency due to glucocorticoid-mediated inhibition of hormone secretion in a variety of species. We therefore investigated effects of stress related to management of mares around artificial insemination on secretion of cortisol and fertility parameters. To avoid further disturbance of mares by frequent blood sampling, faecal cortisol metabolites (fCM) were determined instead (sample collection at 8-h intervals). A total of 50 mares (16 maiden, 17 barren, 12 foaling, 5 teaching mares) were included in the study. Mares were brought to the AI ...
Kidd TJ, Gibson JS, Moss S, Greer RM, Cobbold RN, Wright JD, Ramsay KA, Grimwood K, Bell SC.Pseudomonas aeruginosa is associated with infectious endometritis in horses. Although infectious endometritis is often considered a venereal infection, there is relatively limited genotypic-based evidence to support this mode of transmission. The study sought to determine the relatedness between genital P. aeruginosa isolates collected from a limited geographical region using molecular strain typing. Enterobacterial repetitive intergenic consensus PCR typing was performed on 93 isolates collected between 2005 and 2009 from 2058 thoroughbred horses (including 18 stallions) at 66 studs. While P....
Watson ED, Sertich PL.Embryos, endometrial biopsies, and uterine lavage fluid were collected from pregnant and non-pregnant mares 14 days after ovulation. Embryos were cultured for 20.5 h with and without endometrial tissue from pregnant mares, and endometrial tissue was cultured alone. Endometrial content of PGF tended to be higher (P = 0.06) in non-pregnant than in pregnant mares, but the amount of PGF released from tissue during culture was similar for pregnant and non-pregnant mares. Lavage fluid from non-pregnant mares also tended (P = 0.08) to contain higher concentrations of PGF. Coincubation of embryos with...
Galuppi R, Piva S, Castagnetti C, Iacono E, Tanel S, Pallaver F, Fioravanti ML, Zanoni RG, Tampieri MP, Caffara M.The present study aims to evaluate the prevalence, pattern of spread and risk factors for the transmission of cryptosporidiosis in foals and mares hospitalized in a University Equine Perinatology Unit, where a new subtype family of Cryptosporidium horse genotype was described by Caffara et al. (2013). Mares (36) and foals (37) hospitalized during the 2012 foaling season were included. Multiple sampling from each animal was performed (a total of 305 stool samples were collected). One hundred and eleven environmental samples (gauze swabs) were also collected before and after the breeding season....
Klohonatz KM, Nulton LC, Hess AM, Bouma GJ, Bruemmer JE.Maternal recognition of pregnancy (MRP) in the mare is an unknown process. In a non-pregnant mare on day 14 post-ovulation (PO), prostaglandin F2α (PGF) is secreted by the endometrium causing regression of the corpus luteum. Prior to day 14, MRP must occur in order to attenuate secretion of PGF. The embryo is mobile throughout the uterus due to uterine contractions from day of entry to day 14. It is unknown what signaling is occurring. Literature stated that infusing oil or placing a glass marble into the equine uterus prolongs luteal lifespan and that in non-pregnant mares, serum exosomes co...
Vilés K, Rabanal R, Rodríguez-Prado M, Miró J.Artificial insemination (AI) involving the placing of frozen-thawed semen directly into the jenny uterine body is associated with very low pregnancy rates. This might be because of an exacerbation of the acute response of the endometrium to sperm, as seen in mares with persistent induced mating endometritis. Pregnancy rates can be increased in such mares, however, by including anti-inflammatory treatments in the insemination protocol (Bucca S, Carli A, Buckley T, Dolci G, Fogarty U. The use of dexamethasone administered to mares at breeding time in the modulation of persistent mating induced e...
Sarwar G, Botting HG, Davis TA, Darling P, Pencharz PB.Preterm and term transitional milks of human subjects and mature milks of human subjects, non-human primates and non-primates were analysed for free amino acids (AA) using precolumn phenylisothiocyanate derivatization and liquid chromatography. Differences in free AA between three types of human milk were small. Milks of pinnipeds (seals and sea lions) contained the highest levels of total free AA (8634-20,862 mumol/l), while the milks of cows and sheep had the lowest levels of total free AA (1061-1357 mumol/l). The milks of human subjects, chimpanzees (Pan troglodytes), gorillas (Gorilla gori...
Coignoul FL, Cheville NF.Six pregnant mares were given equine viral arteritis virus intravenously. Tissues from genital tracts, placentae, and fetuses were examined by light and electron microscopy to study the mechanism of abortion. Four mares which died with acute disease had diffuse vacuolation of endometrial epithelium and systemic necrotizing vasculitis. Two of these mares had dead fetuses and two had live fetuses; virus was isolated from tissues of one live fetus. Placentae of mares dying from acute disease did not have lesions attributable to infection; virus was isolated from two of these placentae. One of the...
Segabinazzi LG, Friso AM, Correal SB, Crespilho AM, Dell'Aqua JA, Miró J, Papa FO, Alvarenga MA.Persistent mating-induced endometritis (PMIE) results in decreased fertility in horses, thereby causing a significant impact in the horse market. Platelet-rich plasma (PRP), a modulator of the inflammatory response, has been largely used in veterinary medicine. Here, we investigated the effects of PRP on uterine inflammation, conception rate, endometrial polymorphonuclear neutrophil (PMN) migration, and COX-2 protein levels in the endometrial tissue. Thirteen PMIE-susceptible mares were used for artificial insemination (AI). The mares were inseminated with fresh semen in three consecutive cycl...
Weber R, Hospes R, Wehrend A.The aim of this study was to summarize the current status of the possible causes, clinical symptoms and pathogenesis of abortion in the mare and to evaluate the frequency of varying causes of abortion in German thoroughbred breeding. An analysis of the literature using electronic libraries, journals and textbooks was performed. In addition, the results of examinations of 123 abortions of thoroughbred breeding in central Germany were evaluated. In the literature, bacterial infections are the most frequently described cause of abortion. Other important causes are infections with equine herpesvir...
Smith DJ, Hamblin AS, Edington N.Evidence is presented to show that activation of endothelial and leucoyte adhesion molecules is a key step in transferring virus from infected leucocytes; and determines the restricted tissue tropism. A range of tissues from 2 experimentally infected mares in late pregnancy at 4 and 8 days after infection with EHV-1 were compared with those from normal pregnant and nonpregnant mares. Rabbit antisera to equine activated endothelial cell molecules were used to identify which tissues expressed these molecules in normal nongravid and gravid mares, and to investigate whether the range of tissues wa...
Smith KC, Whitwell KE, Mumford JA, Gower SM, Hannant D, Tearle JP.Twelve Welsh Mountain pony mares in late gestation were infected intranasally with EHV-1 (AB4 isolate) at dose rates from 10(3) to 10(7.3) TCID50. This resulted in 3 cases of paresis, at Days 9, 10 and 12 after inoculation, and 5 abortions, at Days 6, 9, 18, 19 and 20. Euthanasia was performed between Days 6 and 21, with collection of uterine specimens for histopathology, virus isolation and immunoperoxidase staining from the pregnant horn, non-pregnant horn and body. EHV-1 replication in endometrial vessels was detected as early as Day 6 and was maximal at Days 9-11, when widespread thrombois...
