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.
Nieman RT, Lamim LI, Del Fava C.Fetal loss in mares can result from a range of causes, including infectious agents or noninfectious conditions such as neoplasia, which may originate from either the fetus or the dam. Among neoplastic conditions, teratomas are rarely reported and, to date, have not been described in the equine fetal testis. Teratomas arise from the partial differentiation of pluripotent germ cells and may occur in young and adult horses, typically in cryptorchid testes. Their gross and histopathological features vary widely between cases. This report describes a rare case of bilateral fetal testicular teratoma...
Toishimanov M, Zhanten O, Kanat R, Beishova I, Ulyanov V, Assanbayev T, Sharapatov T, Daurov D, Daurova A, Sapakhova Z, Nametov A, Shamekova M.This study aimed to evaluate the chemical composition of milk from Kazakh mares kept under free-grazing conditions on natural pasture without supplementary feeding. Fifty Kazakh mares were aged 3 to 13 years, kept in herds, and categorized by age, number of foalings, and lactation stage for statistical analysis. Milk samples were collected, chilled, and analyzed on the same day using a Milkoscan FT2. The composition of fat, protein, lactose, total solids, casein, and other components was examined. Statistical analyses, including ANOVA, PCA, CDA, and Pearson correlation analysis, were performed...
Viljanto M, Cutler C, Habershon-Butcher J, Hincks P, Scarth J.The use of testosterone in racehorses is predominantly monitored using international urine and plasma concentration-based thresholds and complementary steroid ratios. To date, there has been no published pharmacokinetic study on transdermally applied testosterone products in horses and whether their use could result in adverse analytical findings. Therefore, quantitative analysis of testosterone and epitestosterone in urine and testosterone in plasma samples was performed following a pilot multi-dose transdermal Testogel administration (1 mg/kg once a day for 7 days on clipped skin) to one...
Janczarek I, Gazda I, Barłowska J, Kurnik J, Łuszczyński J.It is assumed that horses have a strong herd instinct that cannot be suppressed by any form of social support from humans. The aim of this study was to assess the behaviour and heart rate parameters of horses that received various forms of human support during short-term social isolation. The research material consisted of 12 clinically healthy recreational warmblood mares and geldings. The test was carried out four times. The research test consisted of two parts, which began in the presence of accompanying horses and under conditions of social isolation, with and without support provided by a...
Parra MT, Ayala MSF.A retrospective study was conducted at the Foal Care Equine Perinatology Center in Colombia from October 2017 to May 2023. The goal was to analyze the most frequent pathologies, as well as assess the sexes, ages, and breeds of the patients, with an emphasis on the perinatal population. Out of 945 clinical histories, 776 pertained to perinatology. Survival rates were calculated, and a descriptive analysis was performed. The overall survival rate for neonates was 73.6%, with females constituting 57% of the neonatal patients. The most prevalent breed among mares and neonates was the Creole Colomb...
Lection J, Schnobrich M, Wagner B, Byron M, Back B, Rollins A, Castro Alves RF, Cheong SH, Diel de Amorim M.To evaluate inflammatory cytokine and chemokine concentrations in endometrial samples collected by cytobrush or swab as a potential screening diagnostic marker for equine endometritis. Unassigned: 88 mares had endometrial samples collected, which included cytobrush, swab, and/or biopsy. Clinical reproductive records, reproductive ultrasound examination, endometrial cytology and culture results, and biopsy grading score were recorded. Fluorescent bead-based multiplex assays for the inflammatory markers interferon-γ, interferon-α, IL-1β, IL-4, IL-10, IL-17A, soluble CD14, tumor necrosis facto...
Ren X, Xue Y, Shen Z, Liu X, Chang X, Meng J, Ren W, Wang J, Yao X, Zeng Y.Branched-chain amino acids (BCAAs) play a crucial role in regulating nutritional metabolism in lactating animals. However, limited research has been conducted on BCAAs in equines. This study aimed to investigate the effects of different doses of BCAA supplementation on plasma and milk amino acid profiles in Yili mares, as well as the growth performance of their suckling foals, thereby providing a scientific basis for optimizing feeding management practices. Eighteen pairs of Yili mares and their sucklings were randomly assigned to four groups: a control group (Group D, no BCAA supplementation)...
da Fé VCS, Dos Santos VMO, de Lima ACB, Hernandes MSP, Caldara FR, Gomes MNB.This study aimed to evaluate the effect of auditory stimuli on mares and geldings during social isolation and movement restriction, and their ability to promote the reduction of stress responses. The research was conducted with eight Pantaneiro horses, divided into Experiment I (4 mares) and Experiment II (4 geldings), both experiments were executed equally using a 4x4 Latin square design with experimental (classical, country and new age) and control (no music) treatments. Physiological parameters (heart rate, heart rate variability, respiratory rate, ocular temperature by infrared thermograph...
Bailey CS, Beachler TM, Mochel JP, Wulf LW, Yaeger M, Kundu D, Withowski K, Papich MG.Despite their widespread clinical use, there is limited pharmacokinetic data for many equine intrauterine antimicrobials. This study aimed to measure the concentration of gentamicin and penicillin in the uterine fluid of mares following infusion of either a standard (PPGent) or long-acting (LA-PPGent) compounded formulation. We hypothesized that both formulations would result in therapeutic concentrations, with total concentrations sustained for longer using the long-acting formulation. Mares were administered 2400 mg of procaine penicillin and 200 mg of gentamicin via a single intrauterin...
Hannan MA, Watanabe H, Takeyama A, Yoshida S, Wudamu D, Lkhagvasuren N, Claes A, Stout TAE, Cheong SH, Haneda S, Nambo Y.This study evaluated the viability of in vitro embryo production using ovum pick-up (OPU) and intracytoplasmic sperm injection (ICSI) as breeding techniques for pure and crossbred Hokkaido native ponies (n = 9). Oocytes were collected using transvaginal ultrasound-guided follicle aspiration. ICSI was performed on in vitro matured oocytes using frozen semen. Embryonic cultures were monitored using time-lapse cinematography. Blastocysts were cryopreserved and, after thawing, were transferred non-surgically into recipient mares. Over nine OPU sessions, the mean number of aspirated follicles was 2...
Ziadi C, Valera M, Laseca N, Perdomo-González D, Demyda-Peyrás S, de Los Terreros AR, Molina A. By simultaneously integrating both genotyped and non-genotyped animals into genetic evaluation, the single-step genomic BLUP method enhanced the accuracy of genetic assessments. This study aimed to compare the increase in prediction reliability (R) between restricted maximum likelihood (REML) and single-step genomic REML (ssGREML) in the Pura Raza Española (PRE) horse breed. The dataset comprised reproductive records for seven fertility traits from 47,502 females, with a total of 57,316 animals represented in the pedigree. A total of 4009 animals were genotyped using the EQUIGENE 90K SNP ar...
Hosseinzadeh S, Nofouzi K, Hasanzadeh F, Esmaeili S, Ayen E.Q fever is a frequently occurring illness that is induced by the bacterium ) that can infect humans and various animals. It targets the macrophage cells in the tissues, and circulating monocytes. Unassigned: This study was conducted between 2022 and 2023 in the West Azerbaijan and Ardabil provinces of northwestern Iran to examine the presence infection of . Specimens were obtained by swabbing from 140 mares (70 from each province) and 20 stallions (10 from each province) which were apparently healthy, and their DNA was analyzed using quantitative PCR assay detecting the element of the bacteri...
Hosseinzadeh S, Nofouzi K, Hasanzadeh F, Esmaeili S, Ayen E.Q fever is a frequently occurring illness that is induced by the bacterium ) that can infect humans and various animals. It targets the macrophage cells in the tissues, and circulating monocytes. Unassigned: This study was conducted between 2022 and 2023 in the West Azerbaijan and Ardabil provinces of northwestern Iran to examine the presence infection of . Specimens were obtained by swabbing from 140 mares (70 from each province) and 20 stallions (10 from each province) which were apparently healthy, and their DNA was analyzed using quantitative PCR assay detecting the element of the bacteri...
Filho RRR, França DS, Alonso MA, Riccio AV, Affonso FJ, Brito MM, Francischini MCP, Nichi M, Boakari Y, Fernandes CB.During gestation, there is a higher energy demand which increases oxygen requirements. As a result, there is an elevated production of reactive oxygen species. Notably, unlike in horses, the effects of maternal age and parity on women's oxidative profiles are well-documented. Thus, this study aimed to investigate oxidative changes in mares during the last third of gestation and the postpartum period, considering age and parity. Seventeen mares were categorized by age (3-7, 8-11, ≥12 years) and parity (nulliparous, 1-3, 4-6 parities). Oxidative processes were assessed using Thiobarbituric Aci...
Bouquet A, Nicol C, Díez-León M.The natural behaviour of wood-chewing (WC) in horses may, under certain conditions, become excessive or it may precede crib-biting . However, the potential causes of WC, including frustrated foraging motivation) or developmental exploratory or teething behavior are poorly understood. We studied WC in 31 mares and their foals, examining associations with browsing access, stocking density, foal sex and performance of other non-nutritive oral behaviors. Behaviors (counts/hour) were recorded by all-occurrences sampling during focal, continuous observations of grazing,resting and suckling for 20 ...
Rajapakse S, Fernando N, Dreyfus A, Smith C, Rodrigo C.Leptospirosis is a zoonotic bacterial infection that is prevalent across all continents and is caused by pathogenic spirochaetes of the genus Leptospira. Although infection can be asymptomatic, symptomatic disease can vary in severity from mild to severe illness, the latter characterized by icterus and/or multi-organ dysfunction and potentially death. An estimated one million cases of leptospirosis occur globally each year, resulting in ~60,000 deaths. The pathogenesis of severe leptospirosis is poorly understood but is believed to involve an interplay between genetic predisposition, pathogen ...
Renaudin CD, Picandet V, Kass PH.Using the equation of Hartwig et al. and the table established for light breed horses, day of gestation was predicted in 108 Warmblood (WB) and 59 racehorses (Thoroughbred [TB] and Standardbred [STB]) pregnant mares. In WB, gestational ages were predicted within 2 weeks from 100 to 200 days of gestation using biparietal diameter (BPD), aortic diameter (AortD) or femur length (FL); within 2 weeks from 100 to 250 days using BPD or AortD; within 2 weeks from 100 to 300 days using BPD alone; and within 3 weeks from 100 to 350 days using eye approximated volume (EyV) alone. In the ...
de la Rebière de Pouyade G, Binard M, Deleuze S, Ponthier J.Standing caesarian section (C-section) in mares is poorly documented in the literature. It is reportedly straightforward to perform for veterinarians experienced in bovine practice and is more accessible and less expensive than recumbent techniques. The study aimed to create a survey to report the outcomes of in field C-section through a flank laparotomy with the mare standing under sedation. Unassigned: A survey was developed for field veterinarians practicing standing C-sections. Data were collected regarding the veterinarian's experience and practice type, details about the mare and the rea...
da Silva-Álvarez E, Gómez-Arrones V, Correa-Fiz F, Martín-Cano FE, Gaitskell-Phillips G, Carrasco JJ, Rey J, Aparicio IM, Peña FJ, Alonso JM....This study aims to unveil potential differences in the vaginal and uterine microbiomes in mares and jennies, and to identify possible mechanisms involved in uterine immune homeostasis. The microbiota was characterized using 16S rRNA sequencing, and the uterine proteome was analyzed using UHPLC/MS/MS in 18 samples from healthy mares and 14 from jennies. While taxonomic analysis revealed high interspecies similarities, β-diversity analysis showed distinct clustering, with only two vaginal taxa and five uterine taxa differing between species. Despite compositional differences, PICRUSt analysis s...
Quattrini C, Knych HK, Magdesian KG.Alprazolam is used to facilitate mare-foal bonding in aggressive or anxious postpartum mares. In humans, alprazolam crosses the blood-milk barrier, but the amount transferred into milk is minor and compatible with breastfeeding as the relative infant dose is < 10%. Similar data are not available for horses. The aim of this study was to measure alprazolam in serum and milk of mares (milk: serum ratio) administered alprazolam, and to determine alprazolam serum concentrations in nursing foals to estimate the extent of absorption. This was a prospective observational study involving 7 healthy...
Wójtowicz A, Sadowska A, Piotrowska-Tomala K, Szóstek-Mioduchowska A.The role of AREG in the development of fibrosis in the progression of endometrosis in mare remains unknown. We aimed to determine the effects of AREG on fibroblast functional characteristics as well as the expression of extracellular matrix (ECM)-associated genes in fibroblast derived from non-fibrotic and fibrotic equine endometria. Our findings suggest that the mechanisms associated with ECM remodeling regulated by AREG in non-fibrotic fibroblasts may be dysregulated in the progression of fibrosis in endometrosis.
Nabenishi H, Tsuda T, Omoya Y, Ishii T.This study aimed to detect characteristic changes in the behavior and body surface temperature (BST) of pregnant mares before parturition using camera image analysis. A total of 53 pregnant Thoroughbred mares, which were individually stabled in box stalls, were included in this study. The mares were continuously monitored using a digital camera system comprising a thermal imaging camera and a visible camera. For the automatic determination of the x and y coordinates of each mare, the centroid of the mares was calculated using image processing software. Subsequently, trajectory analysis was per...
Boshuizen B, De Maré L, Oosterlinck M, Van Immerseel F, Eeckhaut V, De Meeus C, Devisscher L, Vidal Moreno de Vega C, Willems M, De Oliveira JE....Aleurone, derived from the bran layer of grains like wheat and barley, has demonstrated positive effects on energy metabolism in pigs, mice, and untrained horses, influencing glucose-insulin dynamics and gut microbiome composition. Training itself enhances insulin sensitivity in horses, similar to the improvements in performance capacity observed in human athletes. This study aimed to investigate whether aleurone supplementation provides additional benefits to training by modulating insulin metabolism and gut microbiota in Standardbred mares. Unassigned: Sixteen Standardbred mares (aged 3-5 ye...
Van den Branden E, Salamone M, Broothaers K, Peere S, Polfliet E, Dewulf M, Van Steenkiste G, van Loon G, Smits K, Govaere J.The use of transvaginal ultrasound-guided follicle aspiration (TVA) for oocyte collection has become a widely used procedure in horses for embryo production (IVEP). The TVA procedure is characterized by various manipulations, which are physical restraint, perineal preparation, transrectal palpation, insertion of an intravaginal device, and needle punctures. These repeated transvaginal and transovarian punctures have raised concerns about their potential effects on mare welfare. Our study aimed to investigate the effects of TVA manipulations, and especially puncturing, on pain and stress in ma...
Carvalho IB, Branco S, Laranjo M, Queiroga MC, Bettencourt E.Uterine health is paramount to fertility in broodmares and for the success of a breeding project, and the Lusitano breed is no exception. This study aimed to characterize the mare uterine microbiota using practical clinical evaluation methods. Mares were examined by transrectal palpation and ultrasonography, followed by the collection of samples by one of three different techniques: uterine lavage, biopsy, or swab. The results of cytology, histology, microbiology, and antimicrobial susceptibility testing were recorded, and statistical analyses were performed. Inflammation was present in 42.2% ...
Changes in the global climate pose a severe threat to human and animal welfare and productivity. Total proteins (TP), globulins (GLOB), albumins (ALB), alkaline phosphatase (ALP), creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), blood urea nitrogen (BUN), γ-glutamyl transferase (GGT), and creatinine (CREA) were evaluated during a three-year monitoring period (2021-23) on 16 Thoroughbred retired mares from the regional Golkoy Breeding Farm in Kastamonu- Turkey. The following thermal and hygrometric parameters were gathered: ambient temperature (AT), relative...
Muñoz-Jurado A, Requena F, Agüera EI, Escribano BM.Anti-Müllerian hormone (AMH) is a dimeric glycoprotein belonging to the superfamily of the transforming growth factor-β. Due to the discovery of AMH functions, relative to the ovarian function, it is being postulated as being a highly important marker in studies on mammalian reproduction. Therefore, the objective of this review was to describe the role of this hormone in different reproductive aspects of female mammals, taking women, cows, and mares as reference species. The relationship between ovarian reserve and AMH was analysed, and it has been verified that there is a relationship betwe...
There are four genotypes of ovine papillomaviruses (OaPVs): OaPV1, OaPV2, and OaPV4, which are ovine delta papillomaviruses responsible for epithelial and mesenchymal cell infections, and OaPV3, an epitheliotropic Dyokappapapillomavirus associated with cutaneous tumors in sheep, including squamous cell carcinoma. Vaginal swabs of healthy mares were evaluated for the presence of PVs to investigate whether the vaginal virobiota of asymptomatic mares harbored OaPVs. High-performance digital droplet polymerase chain reaction (ddPCR) was used to quantitatively detect OaPV types 1-4 DNA in 94 vagina...
Abdelnaby EA, ElKader NAA, Yehia SG, Salem NY, Ramadan ES, Khattab MS, Farghali HA, Emam IA.This study aimed to demonstrate the vaginal tissue alterations via vaginal biopsy and hemodynamic alterations by introducing chromoendoscopy to analyse the effect of equine vaginitis on the oxidative and hormonal profile. Mares were divided into normal mares (N = 10) and affected mares (N = 10). Animals were subjected to Doppler ultrasonographic evaluation, endoscopic examination, oxidative stress was estimated, and biopsy samples were taken for histopathology and immunohistochemistry. Uterine body (UB) thickness (mm), circumference (mm) and area (mm) elevated significantly in infected...
Wagner JCP, Edwards M, Trivedi S, Minter LJ, Ange-van Heugten K.Microquantity laboratory procedures (<5 mL) are often used to analyze milk from non-bovid or less common species due to limited available samples and small sample sizes, unlike the large quantities of milk needed for macroquantity (~20 mL) assays standard in the commercial dairy industry. To better understand microquantity milk laboratory analyses, quarter horse () milk from North Carolina State University (females = 4, n = 43) and California Polytechnic State University (females = 4, n = 42) equine centers was compared to investigate differences in macronutrient composition from 4 to 130 d...
Allen GP, Bolin DC, Bryant U, Carter CN, Giles RC, Harrison LR, Hong CB, Jackson CB, Poonacha K, Wharton R, Williams NM.An emerging problem of equine herpesvirus-1 (EHV-1) infection in horses in the USA is a high-mortality myeloencephalopathy that commonly occurs where large numbers of horses are stabled. EHV-1 isolates recovered from recent neurological outbreaks represent a mutant virus strain that possesses enhanced neuropathogenicity. A central question of EHV-1 myeloencephalopathy is the latency carriage rate for these mutants of EHV-1 in USA horse populations. Objective: To estimate the prevalence of neuropathogenic strains of EHV-1 as latent infections in the Thoroughbred broodmare population of central ...
Allen WR.The equine embryo takes 6 days to traverse the oviduct and, when it finally enters the uterus, it remains spherical in shape and moves continually throughout the uterine lumen until day 17 after ovulation to deliver its maternal recognition of pregnancy signal to the entire endometrium. Between day 25 and day 35 after ovulation, the trophoblast cells of a discrete annulate portion of the chorion multiply rapidly and acquire an invasive phenotype and, between day 36 and day 38, migrate deeply into the maternal endometrium to form the equine-unique endometrial protuberances known as endometrial ...
Albihn A, Båverud V, Magnusson U.Uterine microbiology and antimicrobial susceptibility was investigated in 239 mares with fertility problems in a prospective study in Sweden. Uterine swab samples were collected with double guarded swabs and transported overnight before being cultured. The Minimum Inhibitory Concentrations (MIC) was determined for a panel of antimicrobials. From 152 of the 239 mares at least one bacterial species was isolated, most frequently E. coli (104 isolates), beta-haemolytic streptococci (31) and fungi (16). beta-haemolytic streptococci were more frequently (p < 0.01) associated with clinical endomet...
Conley AJ.Analytical advancements, especially methods using gas or liquid chromatography tandem mass spectrometry, have allowed more specific and reliable measurement of multiple steroid hormones in the plasma of mares throughout gestation and the periparturient period. Data such as these will form the central focus of this review. The comprehensive analyses possible with liquid chromatography tandem mass spectrometry illuminate the key physiological and developmental transitions that make equine gestation unique. Weeks 6 to 20 encompass endometrial cup formation and equine chorionic gonadotropic secret...
Gabryś J, Kij-Mitka B, Sawicki S, Kochan J, Nowak A, Łojko J, Karnas E, Bugno-Poniewierska M.The in vitro maturation (IVM) of equine oocytes is still not efficient and does not yield consistent results. The specific requirements of equine oocytes during this process are still largely unknown, which hinders the development of assisted reproductive techniques (ART) in this species. Because the ovarian follicle microenvironment supports oocytes in their acquisition of developmental competence, follicular fluid seems to be a substantial source of bioactive factors that could support the IVM process. Extracellular vesicles (EVs) are cell-secreted molecules in body fluids that are able to ...
Barba M, Martínez-Boví R, Quereda JJ, Mocé ML, Plaza-Dávila M, Jiménez-Trigos E, Gómez-Martín Á, González-Torres P, Carbonetto B....Lactic acid bacteria (LAB) dominate human vaginal microbiota and inhibit pathogen proliferation. In other mammals, LAB do not dominate vaginal microbiota, however shifts of dominant microorganisms occur during ovarian cycle. The study objectives were to characterize equine vaginal microbiota in mares by culture-dependent and independent methods and to describe its variation in estrus and diestrus. Vaginal swabs from 8 healthy adult Arabian mares were obtained in estrus and diestrus. For culture-dependent processing, bacteria were isolated on Columbia blood agar (BA) and Man Rogosa Sharpe (MRS)...
Heldens JG, Hannant D, Cullinane AA, Prendergast MJ, Mumford JA, Nelly M, Kydd JH, Weststrate MW, van den Hoven R.Pregnant mares and young foals were vaccinated with Duvaxyn EHV1,4, an inactivated and adjuvanted vaccine containing both the EHV-1 and 4 antigens. SN and CF antibody titres were induced two weeks after first vaccination. Antibody levels were boosted after second vaccination, however they never reached the levels induced after virus challenge. Young foals were challenged with virulent EHV-1 and EHV-4 field viruses. Pregnant mares were challenged with the highly abortigenic EHV-1 strain Ab4. Vaccinated animals showed a clear reduction in clinical signs and virus excretion compared to unvaccinat...
Carter AM, Enders AC.Epitheliochorial placentation is a derived condition and has evolved separately in strepsirrhine primates and laurasiatherians (pangolins, whales, and hoofed mammals). Usually it is associated with a long gestation period, small litters, and precocial young. Oxygen transfer is facilitated by indenting of the uterine and trophoblast epithelia by maternal and fetal capillaries, respectively. Histotrophic nutrition is important, and adaptations include areolas and hemophagous regions. In pigs and horses, for example, iron is transported as uteroferrin secreted from the uterine glands and taken up...
Overbeck W, Witte TS, Heuwieser W.The objective of this study was to compare the accuracy of a uterine swab (US), a cytological brush (CB) and an endometrial biopsy (EB) to detect subclinical endometritis in mares. Cytological and bacteriological results of all three techniques were related to histological occurrence of polymorphonuclear neutrophils (PMNs) in the stratum compactum, commonly known as 'best standard'; to diagnose endometritis. Samples were taken from 55 mares of different breeds without clinical signs of endometritis. Samples for US, CB and EB were collected, smeared on a microscopic slide and cultured for bacte...
Salmonella enterica subsp. enterica serovar Abortusequi is frequently reported as a cause of abortion in mares and neonatal septicemia and polyarthritis in Asian and African countries, but only sporadically in Europe and the United States. We report an outbreak of S. Abortusequi in foals in Italy, characterized by high mortality. In a herd of Murgese horses, 10 of 34 newborns died at birth and a further 7 died, after developing severe clinical signs, during the first 10 d of life. Tissue specimens from different organs of 2 dead foals, synovial fluids from 4 sick foals, and vaginal and rectal ...
Katila T.This review suggests a classification for uterine diseases of mares. Information is presented on the prevalence of endometritis in the past and at present. The review describes uterine sampling techniques for mares: swabbing, cytobrushing, low volume lavage and biopsy. The performance of culture, cytology and histology and threshold values is discussed. Correlations between different diagnostic methods and fertility are presented, as well as specificities, sensitivities and positive and negative predictive values of the diagnostic methods. The necessity for double-guarded techniques is emphasi...
Scoggin CF.Advancing age can adversely affect a thoroughbred brood-mare's reproductive efficiency and influence the commercial and athletic potential of her progeny. Causes for the decline in fertility include decreased oocyte and embryo quality, anatomical defects and endometrial degeneration. In addition, evidence exists that as the age of a dam increases, her foals will be at increased risk of morbidity and mortality during the neonatal period. Health issues can have lasting and deleterious effects on surviving foals, including decreased sale value and reduced athletic performance. The purpose of this...
Snider TA, Sepoy C, Holyoak GR.The equine endometrial biopsy, an important tool in equine reproduction science, has experienced a rich period of increasing knowledge, development, and application over the past 40 y. Much of the foundational work in this field was conducted by Dr. Robert M. Kenney. In view of his recent passing, this review is dedicated to our alumnus, Dr. Robert M. Kenney (OSU, 1954). In this manuscript, we pay tribute to Kenney-eponymous for the equine endometrial biopsy grading system-by reviewing the procedure. We present this review in three parts: 1) how observational data are acquired; 2) how these da...
Kydd JH, Wattrang E, Hannant D.In general, vaccines containing inactivated equine herpesvirus-1 (EHV-1) fail to prevent abortion in pregnant mares following infection with a virulent strain of EHV-1. We have tested the hypothesis that resistance to EHV-1-induced abortion in pregnant mares is associated with high frequencies of EHV-1 specific, major histocompatibility complex (MHC) class I-restricted, cytotoxic T lymphocytes (CTL) in the circulation. To test this theory, three groups of pregnant mares were assembled with varying backgrounds of infection or vaccination in an attempt to mimic the immune status of the general p...
Ball BA, Conley AJ, MacLaughlin DT, Grundy SA, Sabeur K, Liu IK.Anti-Müllerian hormone (AMH), also known as Müllerian inhibiting substance (MIS), is expressed by granulosa cells in females of many mammalian species, and circulating AMH concentrations have been used to monitor granulosa-cell tumors (GCT) in women. The objective was to characterize expression of AMH in equine GCT, and in normal equine ovaries, based upon immunohistochemistry (IHC), using a polyclonal primary antibody directed against human AMH. Equine GCT (n=27) and normal equine ovaries (n=10) were examined by IHC. In addition, sera from four mares with GCT were characterized for AMH bioa...
Hong CB, Donahue JM, Giles RC, Petrites-Murphy MB, Poonacha KB, Roberts AW, Smith BJ, Tramontin RR, Tuttle PA, Swerczek TW.Pathologic and microbiologic examinations were performed on 1,211 aborted equine fetuses, stillborn foals, and placentas from premature foals in central Kentucky during the 1988 and 1989 foaling seasons to determine the causes of reproductive loss in the mare. Placentitis (19.4%) and dystocia-perinatal asphyxia (19.5%) were the 2 most important causes of equine reproductive loss. The other causes (in decreasing order) were contracted foal syndrome and other congenital anomalies (8.5%), twinning (6.1%), improper separation of placenta (4.7%), torsion of umbilical cord (4.5%), placental edema (4...
Battsetseg B, Lucero S, Xuan X, Claveria FG, Inoue N, Alhassan A, Kanno T, Igarashi I, Nagasawa H, Mikami T, Fujisaki K.The potential role of Boophilus microplus as a natural tick vector of Babesia equi and Babesia caballi in Brazilian horses was assessed using nested polymerase chain reaction (PCR)-based marker assay. B. equi merozoite-specific 218bp gene fragment was detected in almost 96% of horse blood samples, and 45.3-62.5% of females, eggs, larvae, and nymphs of B. microplus collected from 47 horses at Campo Grande in the State of Matto Grosso, Brazil. Except for the partially-fed female ticks, the B. caballi-specific 430bp gene fragment was amplified from horse blood samples, and all developmental stage...
Ferris RA, McCue PM, Borlee GI, Loncar KD, Hennet ML, Borlee BR.In this study, we evaluated the ability of the equine clinical treatments N-acetylcysteine, EDTA, and hydrogen peroxide to disrupt in vitro biofilms and kill equine reproductive pathogens (Escherichia coli, Pseudomonas aeruginosa, or Klebsiella pneumoniae) isolated from clinical cases. N-acetylcysteine (3.3%) decreased biofilm biomass and killed bacteria within the biofilms of E. coli isolates. The CFU of recoverable P. aeruginosa and K. pneumoniae isolates were decreased, but the biofilm biomass was unchanged. Exposure to hydrogen peroxide (1%) decreased the biofilm biomass and reduced the CF...
Chavatte-Palmer P, Velazquez MA, Jammes H, Duranthon V.Epidemiological studies in humans and animal models (including ruminants and horses) have highlighted the critical role of nutrition on developmental programming. Indeed, it has been demonstrated that the nutritional environment during the periconceptional period and foetal development can altered the postnatal performance of the resultant offspring. This nutritional programming can be exerted by maternal and paternal lineages and can affect offspring beyond the F1 generation. Alterations in epigenetic mechanisms have been proposed as the causative link behind the programming trajectories obse...
Kearns CF, McKeever KH, Roegner V, Brady SM, Malinowski K.Plasma concentrations of adiponectin and leptin were measured in 23 mature Standardbred mares (age: 10+/-3 years) and 12 weanling fillies (10 Quarter Horse/Belgian crossbreds and two Quarter Horses; aged: 4+/-3 months) to test the hypothesis that adipocytokines are proportional to adiposity in horses. Rump fat thickness was measured using B-mode ultrasound and percent body fat (% fat) calculated using a published formula for the estimation of fatness in horses. Plasma adiponectin and leptin were determined using radioimmunoassay. In the absence of purified equine adiponectin or leptin, results...
Rebordão MR, Galvão A, Szóstek A, Amaral A, Mateus L, Skarzynski DJ, Ferreira-Dias G.Endometrosis is a degenerative chronic process, characterized by paramount fibrosis development in mare endometrium. This condition is one of the major causes of subfertility/infertility in mares. As in other organs, fibrosis might be a pathologic sequel of many chronic inflammatory diseases. However, aetiology and physiopathologic mechanisms involved in endometrial fibrosis are still controversial. This review presents new hypotheses based on our newest data. As the first line of innate immune defence, systemic neutrophils arrive in the uterus at mating or in the presence of pathogens. A nove...
Allen WR, Wilsher S.Constant, self induced mobility throughout the uterine lumen between days 6 and 17 after ovulation, complete envelopment by a self-secreted glycoprotein capsule between days 7 and 30 and 'injection' of specialised, gonadotrophin-secreting trophoblast cells into the maternal endometrium at days 35-37 are three unusual aspects of equine embryogenesis. The outer trophoblast layer of the allantochorion finally establishes a stable, microvillous contact with the lumenal epithelium of the endometrium around days 40-42 and placentation commences thereafter. The allantochorion elongates steadily until...
Gilkerson JR, Whalley JM, Drummer HE, Studdert MJ, Love DN.The prevalence of EHV-1 and EHV-4 antibody-positive horses was determined using a type specific ELISA on serum samples collected from 229 mares and their foals resident on a large Thoroughbred stud farm in the Hunter Valley of New South Wales in February 1995. More than 99% of all mares and foals tested were EHV-4 antibody positive, while the prevalence of EHV-1 antibody positive mares and foals were 26.2 and 11.4%, respectively. Examination of the ELISA absorbance data for the individual mares and foals suggested that the EHV-1 antibody positive foals had been infected recently with EHV-1 and...
Stout TA, Allen WR.Between at least day 9 and day 16 after ovulation the spherical equine conceptus migrates continuously throughout the uterine lumen, propelled by peristaltic myometrial contractions. This unusually long period of intrauterine movement ensures that the conceptus delivers its anti-luteolytic signal to the entire endometrium to achieve luteostasis. The present experiment tested the hypothesis that prostaglandins stimulate the myometrial contractions that result in the migration of the conceptus. Serial ultrasonographic examinations of the uteri of eight mares performed during 2 h periods between ...
Bucca S, Fogarty U, Collins A, Small V.Ultrasound assessment of feto-placental well-being has found its application in the equine field, as a valid diagnostic tool. Most reports on equine fetal parameters focus on advanced to late gestation. The aim of the present study was to further validate the technique of ultrasound evaluation of the equine fetal environment, by extending its application to earlier stages of pregnancy. Fetal parameters were collected (on 150 pregnancies) over a 3-year period. Data included in the study were selected according to the clinical behaviour of the mare, the neonate/fetus and fetal membranes at the t...
Qi M, Zhou H, Wang H, Wang R, Xiao L, Arrowood MJ, Li J, Zhang L.A total of 262 fecal specimens collected from grazing horses at five locations in Xinjiang, China were examined by PCR for Cryptosporidium spp. and Giardia duodenalis. The Cryptosporidium and G. duodenalis infection rates were 2.7% and 1.5%, respectively. Seven Cryptosporidium-positive specimens were found in foals (16.3%), and four G. duodenalis-positive specimens were found in mares (2.5%). Sequence analyses of 18S rRNA and gp60 genes revealed that seven animals were positive for the subtype VIaA15G4 of Cryptosporidium horse genotype. G. duodenalis assemblages A and B were identified by mole...
Hong CB, Donahue JM, Giles RC, Petrites-Murphy MB, Poonacha KB, Roberts AW, Smith BJ, Tramontin RR, Tuttle PA, Swerczek TW.Placentas from aborted, stillborn, and premature foals were examined during the 1988 and 1989 foaling seasons, and 236 of 954 (24.7%) had placentitis. Microorganisms associated with placentitis were isolated or demonstrated from 162 of 236 (68.6%) placentitis cases. Leptospira spp. and a nocardioform actinomycete were 2 important, newly emerging bacteria associated with equine placentitis. Major pathogens identified in decreasing order were Streptococcus zooepidemicus, Leptospira spp., Escherichia coli, a nocardioform actinomycete, fungi, Pseudomonas aeruginosa, Streptococcus equisimilis, Ente...
Lehmann J, Ellenberger C, Hoffmann C, Bazer FW, Klug J, Allen WR, Sieme H, Schoon HA.The aim of the present study was to characterize the morpho-functional features of endometrosis in barren and foaling mares, using both conventional histopathological and immunohistochemical methods. Endometrial biopsy samples were collected during the physiological breeding season from 159 estrous, clinically healthy mares (mean age 12 years), and the quality and degree of endometrosis was histomorphologically defined. The mares were bred and those that foaled were put in the foaling group whereas those that did not foal were placed in the barren group. Foaling mares were then compared with b...
Lazzari G, Colleoni S, Crotti G, Turini P, Fiorini G, Barandalla M, Landriscina L, Dolci G, Benedetti M, Duchi R, Galli C.Assisted reproduction technologies (ART) are well developed in humans and cattle and are gaining momentum also in the equine industry because of the fact that the mare does not respond to superovulation but can donate large numbers of oocytes through ovum pick up (OPU). After collection, the oocytes can be fertilized by intracytoplasmic sperm injection (ICSI) using a variety of stallion semen samples, even of poor quality, and the resulting embryos can establish high pregnancy rates after cryopreservation and transfer. The discoveries that equine oocytes can be held at room temperature without...
