Endometritis in horses is an inflammatory condition of the endometrium, the inner lining of the uterus, often resulting from bacterial infection. It is a significant reproductive disorder that can affect fertility in mares. The condition can be classified as acute or chronic, depending on the duration and severity of the inflammation. Common causative agents include Streptococcus equi subsp. zooepidemicus, Escherichia coli, and other opportunistic pathogens. Clinical signs may include abnormal uterine discharge, prolonged estrus, and failure to conceive. Diagnosis typically involves uterine cytology, culture, and biopsy. Treatment strategies often include antimicrobial therapy, uterine lavage, and management of underlying predisposing factors. This page compiles peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnostic methods, and treatment options for endometritis in equine reproductive health.
Allen JL, Begg AP, Browning GF.Pseudomonas aeruginosa is an opportunistic pathogen that has been recognized as a cause of endometritis in mares. Pulsed field gel electrophoresis was used to characterize and compare isolates of P. aeruginosa from an outbreak of endometritis and unrelated isolates collected at the same time as the outbreak. The restriction endonuclease digestion patterns and antimicrobial resistance profiles of all outbreak isolates were identical. Therefore, a single strain of P. aeruginosa was responsible for the cases of endometritis. The unrelated isolates could be distinguished from the outbreak strain u...
Cocchia N, Paciello O, Auletta L, Uccello V, Silvestro L, Mallardo K, Paraggio G, Pasolini MP.Endometritis is the most important cause of infertility in barren mares. The quick method of endometrial cytology (EC) has a relatively high reliability in diagnosing endometrial inflammation in the mare. For reliable cytological results, a collection technique that yields many well-preserved cells representative of a large uterine surface area without causing harm to the reproductive tract is required. The aim of the study was to compare three usually employed techniques for collection of endometrial and inflammatory cells (guarded cotton swab, uterine lavage, and cytobrush) in chronically in...
Casagrande Proietti P, Bietta A, Coppola G, Felicetti M, Cook RF, Coletti M, Marenzoni ML, Passamonti F.The objective of this manuscript was to validate published PCR-based methods for detection of β-haemolytic Streptococci by comparison with established bacteriological techniques using 85 clinical isolates recovered from uterine swabs of mares with clinical signs of endometritis and to determine the distribution of SeeL/SeeM and SzeL/SzeM superantigens in isolates of Streptococcus equi subsp. equi (S. equi) and S. equi subsp. zooepidemicus (S. zooepidemicus). The conventional bacteriological techniques showed the vast majority of these isolates (78) were S. zooepidemicus with just 5 Streptococ...
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....
Scherzer J.Reproductive performance in mares can be enhanced by various techniques. Protocols hastening the onset of follicular development help establish pregnancy in mares and ensure that foals are born early in the year. The time spent breeding mares can be reduced by synchronizing estrus and inducing ovulation. After successful fertilization of the oocyte, the developing embryo can survive in the uterus only if postbreeding endometritis, if present, is treated.
LeBlanc MM, Causey RC.Endometritis, a major cause of mare infertility arising from failure to remove bacteria, spermatozoa and inflammatory exudate post-breeding, is often undiagnosed. Defects in genital anatomy, myometrial contractions, lymphatic drainage, mucociliary clearance, cervical function, plus vascular degeneration and inflamm-ageing underlie susceptibility to endometritis. Diagnosis is made through detecting uterine fluid, vaginitis, vaginal discharge, short inter-oestrous intervals, inflammatory uterine cytology and positive uterine culture. However, these signs may be absent in subclinical cases. Hyper...
Hemberg E, Kindahl H, Lundeheim N, Einarsson S.The objectives of this study were to investigate: (i) relationships between early foal health and their dams' reproductive health at mating/conception as well as after parturition and (ii) health status during early foal life and its association with performance as an adult. The study included 35 foals showing clinical symptoms indicating septicaemia, sometimes in combination with other disturbances, within their first 18 h postpartum (Group I). Eighty-eight foals that were healthy during their first few days of life were used as control (Group II). All foals were born in the same region of Sw...
Koblischke P, Kindahl H, Budik S, Aurich J, Palm F, Walter I, Kolodziejek J, Nowotny N, Hoppen HO, Aurich C.We tested the hypothesis that subclinical endometritis occurs after embryo transfer (ET) in the horse. Recipient mares were treated with meclofenamic acid (M) or flunixin meglumin (F) after ET or were left untreated (n=9 per group). Embryos were re-collected 4 days after transfer. Endometrial biopsies were taken for histology and analysis of cyclooxygenase-2 (COX-2) by immunohistochemistry and for PCR. Bacteriological swabs were collected from the uterus and lavage fluid of donor and recipient mares. Progesterone and prostaglandin F(2alpha) release was analysed in recipient mares after ET. Fou...
Bucca S, Carli A, Buckley T, Dolci G, Fogarty U.The present study describes the effect of a single dose of dexamethasone administered to mares at time of breeding. In an initial experiment, the authors investigated safety of treatment. In a second experiment the effect of treatment on the uterine environment, fetal development and pregnancy outcome was examined. In the final part of the study, mares susceptible to persistent mating induced endometritis were identified, by means of a risk factor score system and the effect of treatment evaluated. Results indicated that dexamethasone administered at breeding time did not negatively impact on ...
Dickinson CE, Gould DH, Davidson AH, Avery PR, Legare ME, Hyatt DR, DebRoy C.A postpartum mare and foal were presented for evaluation of fever and lethargy in the mare. The mare was diagnosed with endometritis and initially responded well to treatment. On the second day of hospitalization, the mare developed renal insufficiency characterized by oliguria, azotemia, hemolysis, and thrombocytopenia. Concurrently, the foal developed rapidly progressive central nervous system signs culminating in refractory seizures. Both animals failed to respond to treatment and were euthanized. Thrombotic microangiopathy involving glomeruli was evident on microscopic examination of the m...
Rohrbach BW, Sheerin PC, Cantrell CK, Matthews PM, Steiner JV, Dodds LE.To determine whether treatment with a preparation of Propionibacterium acnes would improve pregnancy and live foal rates in mares with persistent endometritis. Methods: Randomized placebo-controlled clinical trial. Methods: 95 mares with a cytologic diagnosis of persistent endometritis. Methods: Mares were treated with P acnes or placebo (both administered IV) on days 0, 2, and 6. No attempt was made to alter additional treatments administered by attending veterinarians. Information on breeding history, physical examination findings, results of cytologic examination and microbial culture of ut...
LeBlanc MM, Magsig J, Stromberg AJ.Low-volume uterine flush (n=401) was performed in 308 infertile mares to diagnose endometritis. Mares evaluated were either barren after three or more breedings or had two or more unsuccessful embryo recovery attempts during consecutive cycles. Culture results were compared with cytological and histological findings, efflux clarity and pH to substantiate that the micro-organisms recovered were truly pathogens. Cytological specimens were evaluated for presence of epithelial and inflammatory cells, bacteria, yeast and debris. Endometrial biopsies (n=110) were examined for the presence of neutrop...
Troedsson MH.Endometritis is a common cause of infertility in broodmares. In the past, the condition was believed to be exclusively the result of bacterial contamination of the uterus. Treatment strategies were focused on preventing bacteria from entering the uterus and on treating mares with signs of endometritis with antibiotics. More recent research on uterine defense mechanisms has increased our understanding of the pathophysiology of equine endometritis. Additional causative agents have been identified, and we have learned to separate uterine infections and a physiologic breeding-induced endometritis ...
Samper JC, Tibary A.Bacterial, viral and protozoal infections may cause severe reproductive losses. The present paper reviews the risk factors, clinical signs and preventive measures for the most important venereal or potential sexually transmitted diseases in horses. The stallion and use of semen for artificial insemination represent major risk factors for the transmission of bacterial contaminants of the penis, including Streptococcus equi subspecies zooepidemicus, Pseudomonas aeruginosa and Klebsiella pneumoniae, known to cause endometritis and infertility in the mare. The role of the stallion in disease trans...
Neves AP, Keller A, Trein CR, Möller G, Jobim MI, Castilho LF, Cardoso MR, Leibold W, Zerbe H, Klug E, Gregory RM, Mattos RC.This study compared four treatments for bacterial endometritis in mares experimentally infected with Streptococcus zooepidemicus. Twenty-five mares were used, 20 resistant and five susceptible to endometritis. Mares would be in estrus when infected. Twenty-four hours after inoculation, clinical, bacteriological and cytological examinations were performed and repeated until the first occurrence: negative cytology and no Streptococcus growth or the seventh day post-infection. All mares showed clinical signs of endometritis and were assigned to one of the following treatments: (1) intrauterine in...
Yaralioglu-Gurgoze S, Cetin H, Cen O, Yilmaz S, Atli MO.Endometritis is an important factor in infertility. Free radicals play an important role in endometritis and we have investigated their possible role and scavenging systems in endometritis in purebred Arabian mares. The plasma concentration of malondialdehyde (MDA) and erythrocyte glutathione peroxidase (GPx) activity were compared in healthy mares and in mares with endometritis. The level of MDA was significantly increased while GPx activity was decreased in the mares with endometritis. Our findings support the notion that GPx is consumed by increased lipid peroxidation in purebred Arabian ma...
Alghamdi AS, Foster DN, Carlson CS, Troedsson MH.Breeding-induced endometritis (BIE) in the mare is resolved by 36 hr after insemination in resistant mares. However, 10-15% susceptible broodmares fail to do so because of impaired uterine contractility between 7 and 19 hr after exposure to seminal or bacterial challenge, which reduces their fertility. Methods: Nitric oxide (NO) in uterine secretions, and expression of nitric oxide synthase (NOS) in uterine biopsies were compared between susceptible and resistant groups 13 hr after insemination. Results: Susceptible mares had a higher NO in their uterine secretions and greater inducible NOS (i...
Kolm G, Gemeiner M, Deichsel K, Budik S, Aurich J, Aurich C.The failure of clearance mechanisms in the mare's uterus results in persistent inflammation and is considered a major cause of subfertility. Eighteen mares, of which three were susceptible to endometritis and four had been ovariectomised, underwent charcoal clearance testing to evaluate their clearance mechanisms. This consisted of installing 500 mg of charcoal (particle size 4 to 90 microm) added to 50 ml of phosphate-buffered saline (PBS) into the uterus. Forty-eight hours later the uterus was flushed out with 0.0012 per cent methylene blue in 50 ml of PBS for determination of the diluting f...
Zerbe H, Castilho LF, Engelke F, Mattos RC, Schuberth HJ, Klug E, Leibold W.Sufficient numbers of functionally competent polymorphonuclear neutrophil granulocytes (PMN) seem to be of major importance during the course of equine endometritis. In this study, we wanted to establish a method for cryopreservation of functionally competent neutrophils for an intended local endometritis therapy in mares. The separation of leucocytes by hypotonic lysis of whole blood from clinically healthy mares was superior to the separation by dextrose sedimentation. After suspension of the cells in the cryoprotective solution [equine plasma with 5% (v/v) dimethyl sulphoxide (DMSO)], the l...
Zerbe H, Schuberth HJ, Engelke F, Frank J, Klug E, Leibold W.In order to investigate pathogenic mechanisms of acute endometritis in cows and mares, we established an in vivo model in both species. Based on the results of an in vitro transmigration system, human recombinant interleukin-8 (rhIL-8; 1.25 microg per mare and 5 microg per cow in 50 ml phosphate-buffered saline) was used to attract polymorphonuclear neutrophil granulocytes (PMNs) into the uteri. Peak numbers of uterine neutrophils were attracted after 6h, in both cows and mares. On average, mares responded more sensitively than cows, with 15 times higher numbers of rhIL-8-attracted uterine neu...
Vanderwall DK, Woods GL.To determine the effect on fertility of large-volume uterine lavage with lactated Ringer's solution (LRS) performed immediately prior to insemination in mares. Methods: Prospective randomized controlled study. Methods: 20 mares. Methods: Control mares (n = 10) were inseminated with 1 billion (estimated before cooling) progressively motile spermatozoa that had been cooled in a passive cooling unit for 24 hours. Mares (n = 10) in the treatment group were inseminated with 1 billion progressively motile spermatozoa (cooled as described for control mares) immediately after uterine lavage with 4 L o...
Szeredi L, Tenk M, Schiller I, Révész T.In six healthy mares and 24 mares showing reproductive disorders swab samples were taken from the fossa clitoridis to isolate Taylorella equigenitalis, and from the uterus to isolate mycoplasmas, ureaplasmas and other aerobic bacteria. Swab samples were also taken from the uterus for Chlamydia antigen ELISA and Chlamydia PCR studies. The uterus of 27 mares was examined cytologically, and biopsy samples were taken from the endometrium for histological examinations and for immunohistochemical examinations aimed at the detection of chlamydiae. T. equigenitalis, mycoplasmas, ureaplasmas and chlamy...
Madill S.Functional alterations within the reproductive system and in other supporting systems may limit the reproductive capacity of geriatric patients; however, the age of onset and degree of compromise show wide individual variation. Aging of the hypothalamopituitary-ovarian axis in the mare manifests as delayed entry to the breeding season, prolonged follicular phases, reduced response to ovulation induction, irregular cycles, oocyte defects, increased early embryonic death, and, eventually, persistent anestrus. Aging of the reproductive tract may increase her susceptibility to endometritis, compro...
Nikolakopoulos E, Watson ED.Bacteria were infused into the uteri of 5 estrous mares resistant to persistent mating-induced endometritis, first during a control cycle, and then during treatment with clenbuterol, a beta 2 agonist. Uterine cellular response was evaluated 48 h later by transrectal ultrasonography, followed by uterine lavage. During clenbuterol treatment all mares accumulated intrauterine fluid, whereas in the control cycle none of the mares retained fluid. There was no significant difference between the 2 cycles in the cloudiness of the lavage fluid, number of cells per milliliter, percentage of neutrophils ...
Hinrichs K, Betschart RW, McCue PM, Squires EL.Mares with preovulatory follicles >33 mm in diameter were administered hCG and were randomly assigned for aspiration of the dominant follicle at 24 h or 35 h after hCG administration. Oocytes recovered at 24 h were cultured for 12 h before transfer and oocytes recovered at 35 h were cultured for 1 h. Oocytes were transferred by flank laparotomy to the oviduct of the same mare, or to the oviduct of another oocyte donor. Recipient mares were inseminated before and after transfer. The oocyte recovery rates at 24 h and 35 h after hCG administration were not significantly different (10/15 (66%) and...
Nikolakopoulos E, Kindahl H, Watson ED.Mares resistant (n=7) and susceptible (n=9) to persistent mating-induced endometritis were artificially inseminated (AI) during oestrus with chilled extended semen. Blood samples were collected from 30 min before AI, for 2 h after AI and again between 16 and 18 h after AI. Samples were assayed for oxytocin and the PGF2alpha metabolite 13,14-dihydro-15-keto PGF2alpha (PGFM). AI caused a significant increase in oxytocin concentrations in both the resistant and susceptible mares and there was no significant difference in oxytocin release between the two groups of mares. Mean PGFM concentrations w...
Madill S, Troedsson MH, Alexander SL, Shand N, Santschi EM, Irvine CH.The aim of this study was to investigate the effect of different breeding stimuli on uterine contractility and pituitary oxytocin release in five oestrous mares, in order to design better treatments for mares with defective physical uterine clearance mechanisms. Electrodes and strain gauges were implanted surgically on the uterine myometrium and myometrial activity was monitored with a Grass polygraph. A catheter was placed non-surgically in the intercavernous sinus of each oestrous mare to sample pituitary venous blood and a second catheter was placed in the jugular vein. Continuous sampling ...
van Ittersum AR, van Buiten A.Mares with a large vulvar orifice have an increased risk of pneumovagina, which is associated with reduced fertility. Treatment is by means of the Caslick operation, by which size of the vulvar orifice is reduced. Factors that influence the occurrence of pneumovagina are the age and fertility status of the mare. In this study the risk factors for pneumovagina and the effect of the Caslick operation on fertility were investigated. In 1994, 1995, and 1996 a total of 967 mares were sent for service at a stud. Of these mares, 116 underwent a Caslick operation. The operated mares were older than th...
Miragaya MH, Woods GL, Losinno L.The occurrence of uterine and oviductal inflammation, and fertilisation rates, were measured on Day 3 post ovulation in inseminated mares that had either exhibited intrauterine lumenal fluid during a previous dioestrus (Experiment 1) or had acute endometritis induced by intrauterine infusion of 1% glycogen (Experiment 2). Endometritis was assessed by uterine cytology and histology whereas oviductal inflammation was measured histologically. Fertilisation rates were calculated from the percentage of cleaved ova recovered by retrograde flushing of the oviducts. Mares with or without pre-existing ...
Dickinson CE, Gould DH, Davidson AH, Avery PR, Legare ME, Hyatt DR, DebRoy C.A postpartum mare and foal were presented for evaluation of fever and lethargy in the mare. The mare was diagnosed with endometritis and initially responded well to treatment. On the second day of hospitalization, the mare developed renal insufficiency characterized by oliguria, azotemia, hemolysis, and thrombocytopenia. Concurrently, the foal developed rapidly progressive central nervous system signs culminating in refractory seizures. Both animals failed to respond to treatment and were euthanized. Thrombotic microangiopathy involving glomeruli was evident on microscopic examination of the m...
Rohrbach BW, Sheerin PC, Cantrell CK, Matthews PM, Steiner JV, Dodds LE.To determine whether treatment with a preparation of Propionibacterium acnes would improve pregnancy and live foal rates in mares with persistent endometritis. Methods: Randomized placebo-controlled clinical trial. Methods: 95 mares with a cytologic diagnosis of persistent endometritis. Methods: Mares were treated with P acnes or placebo (both administered IV) on days 0, 2, and 6. No attempt was made to alter additional treatments administered by attending veterinarians. Information on breeding history, physical examination findings, results of cytologic examination and microbial culture of ut...
Caissie MD, Gartley CJ, Scholtz EL, Hewson J, Johnson R, Chenier T.Persistent breeding-induced endometritis (PBIE) is a major cause of infertility in mares. Endometrial inflammation that persists until embryonic descent ultimately results in early embryonic death. A poor endometrial biopsy grade (IIb or III) has been identified as a risk factor for PBIE. Intrauterine fluid accumulation (>2 cm in depth), pathologic endometrial edema, and elevated intrauterine neutrophil levels are all clinical features of PBIE. Commonly applied treatment options include uterine lavage and oxytocin therapy. N-acetyl cysteine (NAC), a mucolytic used to treat bacterial endome...
Bucca S, Carli A.Human chorionic gonadotropin (hCG) and dexamethasone have a role in the reproductive management protocols of mares susceptible to persistent mating-induced endometritis (PMIE). However, it is possible that there is interference between these 2 drugs. Objective: The objective of this retrospective study was to determine the efficacy of hCG to induce ovulation in mares treated with dexamethasone at breeding time. Methods: Medical records from 152 mares and 223 cycles were analysed. In 113 cycles, mares susceptible to PMIE were treated with 1500 iu hCG and a single dose of 50 mg dexamethasone, 11...
Watson ED, Stokes CR, Bourne FJ.Both random and directional migration of blood neutrophils from 9 mares susceptible to persistent endometritis were significantly less (p less than 0.05) than neutrophils from 8 resistant mares. Serum from susceptible mares had significantly more (p less than 0.01) chemotactic activity than serum from resistant mares. Although phagocytosis of yeast blastospores by blood neutrophils from 4 resistant and 3 susceptible mares was similar, uterine neutrophils from susceptible mares were significantly worse (p less than 0.01) at phagocytosis than uterine neutrophils from resistant mares. Uterine was...
Köhne M, Hegger A, Tönissen A, Hofbauer L, Görgens A, Sieme H.Bacterial endometritis is a major problem in equine reproduction usually treated with antibiotics, however reports of success rates are scarce. This study collected data from mares diagnosed with intrauterine bacterial growth and compared the outcome of different therapies for bacterial endometritis in German stud farm practice. Data on mares with positive uterine culture results were collected retrospectively in veterinary practices (n = 5; 2018-2022). Information relating to 30 factors (mare, diagnostics, therapy, pregnancy rate) of bacterial endometritis cases (n = 772) were recorded an...
Martínez-Boví R, Sala-Ayala L, Querol-Paajanen A, Plaza-Dávila M, Cuervo-Arango J.PGF is commonly given at the end of embryo flushing (EF) to shorten the interval to the next oestrus and ovulation. Objective: To determine the effect of repeated EF on plasma progesterone concentration, percentage of mares with endometritis, unwanted pregnancy and subsequent fertility in mares flushed without the use of PGF . Methods: Controlled experiments. Methods: Nine mares were inseminated in seven consecutive cycles (n = 63), to either perform an EF (n = 54) 7-9 days after ovulation or left pregnant (n = 9). PGF was not used to induce oestrus. Ultrasound examination and bl...
Retamar GC, Bustos CP, Guillemi EC, Becú T, Ivanissevich A, Mesplet M, Muñoz AJ.Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a mucosal commensal of the lower genital tract in horses and is the most isolated bacterium causing endometritis in mares. The aim of this study was to determine the molecular diversity of S. zooepidemicus obtained from endometritis in mares in Buenos Aires province, Argentina. Thirty isolates obtained from the uterus of mares in 2005 and 2017 were studied. The MLST scheme was applied to identify the Argentinian genotypes and the clonal relationships and patterns of evolutionary descent were identified using the eBURST algorithm - g...
Scholtz M, Guthrie AJ, Newton R, Schulman ML.Three bacteria extensively acknowledged as venereal pathogens with the potential to induce endometritis include Taylorella equigenitalis, the causative agent of contagious equine metritis (CEM), specific strains of Pseudomonas aeruginosa, and certain capsule types of Klebsiella pneumoniae. The United Kingdom's Horserace Betting Levy Board recommends pre-breeding screening for these bacteria in their International Codes of Practice and >20 000 samples are tested per annum in the United Kingdom alone. While the pathogenesis and regulatory importance of CEM are well established, an evaluation...
Dawson FL.Mares rarely ovulate in winter; ovulation is induced by increase in daylight length. Ova accumulate in the oviducts of unserved mares. During pregnancy, corpora lutea accumulate; all regress together at mid pregnancy. Plasma progesterone levels rise and oestrogen levels fall towards the end of pregnancy. Methods are available for early termination of pregnancy and for induction of parturition. Pregnancy can be diagnosed efficiently by rectal examination, and by immunological assay of pregnant mare serum gonadotrophin. Service at the foal heat is associated with an increased prevalence of early...
Swift LA, Christensen BW, Samocha MB, le Jeune SS, Millares-Ramirez EM, Dujovne GA.Although exercise and acupuncture are frequently used therapies to treat persistent postbreeding endometritis, their efficacy to date is unproven. The objective of this study was to determine if exercise and acupuncture are effective methods to reduce intrauterine fluid and compare the effectiveness of these treatments to the use of uterine ecbolics. Twelve mares susceptible to postbreeding endometritis were enrolled in the study with a randomized cross-over design using both positive and negative controls. During each estrous cycle, mares were randomized into one of six treatment groups, incl...
Youngquist RS, Blanchard TL, Lapin D, Klein W.Four groups of five pony mares each were used to determine if the intrauterine infusion of EDTA-Tris solution caused adverse effects on the endometrium. The uteri of mares were infused with either saline or EDTA-Tris solution or biopsied or sham-biopsied without infusion. Acute endometritis developed in one (20%) to three (60%) mares in each group during the seven days following treatment, but there were no differences (P > 0.05) in the incidence of endometritis among the groups. Endometrial fibrosis was not evident in biopsies taken on days 14, 30 and 60 following infusion of saline or EDT...
Da Silva E, Martín-Cano FE, Gómez-Arrones V, Gaitskell-Phillips G, Alonso JM, Rey J, Becerro L, Gil MC, Peña FJ, Ortega-Ferrusola C.Equine endometritis is one of the main causes of subfertility in the mare. Unraveling the molecular mechanisms involved in this condition and pinpointing proteins with biomarker potential could be crucial in both diagnosing and treating this condition. This study aimed to identify the endometritis-induced changes in the endometrial proteome in mares and to elucidate potential biological processes in which these proteins may be involved. Secondly, biomarkers related to bacterial endometritis (BE) in mares were identified. Uterine lavage fluid samples were collected from 28 mares (14 healthy: ne...
Asbury AC, Schultz KT, Klesius PH, Foster GW, Washburn SM.Ten mares, 5 resistant and 5 susceptible to bacterial endometritis, were examined for differences pertaining to the efficiency of phagocytosis of bacteria by neutrophils in the uterus. An assay for chemiluminescence was used to evaluate various schemes of opsonization and relate them to phagocytic rate. 123I-labelled albumin was used to measure protein migration to the inoculated uterus. Neutrophil numbers moving to the uterine lumen were determined. Before inoculation resistant mares were found to have substances in their uterine secretions that opsonized bacteria, resulting in effective phag...
Neves AP, Keller A, Trein CR, Möller G, Jobim MI, Castilho LF, Cardoso MR, Leibold W, Zerbe H, Klug E, Gregory RM, Mattos RC.This study compared four treatments for bacterial endometritis in mares experimentally infected with Streptococcus zooepidemicus. Twenty-five mares were used, 20 resistant and five susceptible to endometritis. Mares would be in estrus when infected. Twenty-four hours after inoculation, clinical, bacteriological and cytological examinations were performed and repeated until the first occurrence: negative cytology and no Streptococcus growth or the seventh day post-infection. All mares showed clinical signs of endometritis and were assigned to one of the following treatments: (1) intrauterine in...
Hansen PJ, Asbury AC.The release of opsonins into the uterine lumen of mares susceptible or resistant to endometritis was examined after intrauterine inoculation of a filtrate of Streptococcus culture fluid or vehicle. Uterine flushings were collected at 0.5 hour before and 2, 4, 6, 8, and 24 hours after inoculation on day 2 or 3 of estrus and on day 7 or 8 after ovulation. Amounts of opsonins in flushings were quantified as the H2O2 produced by leukocytes incubated with flushings-opsonized bacteria, compared with H2O2 produced by leukocytes incubated with nonopsonized bacteria. Opsonin values in flushings increas...
Zerbe H, Castilho LF, Engelke F, Mattos RC, Schuberth HJ, Klug E, Leibold W.Sufficient numbers of functionally competent polymorphonuclear neutrophil granulocytes (PMN) seem to be of major importance during the course of equine endometritis. In this study, we wanted to establish a method for cryopreservation of functionally competent neutrophils for an intended local endometritis therapy in mares. The separation of leucocytes by hypotonic lysis of whole blood from clinically healthy mares was superior to the separation by dextrose sedimentation. After suspension of the cells in the cryoprotective solution [equine plasma with 5% (v/v) dimethyl sulphoxide (DMSO)], the l...
Chiba A, Ujiie Y, Aoki T.While intrauterine fluid (IUF) is observed as mucous in healthy mares during estrus, the presence of IUF during diestrus is an indicator of endometritis. Mating induces endometrial inflammation in healthy mares, called mating-induced endometritis, that disappears within 1-2 days after mating. On the other hand, it is also known that IUF remaining beyond 12 hr after mating can cause persistent inflammation, bacterial growth, and decreased fertility. This study aimed to investigate the relationship between the presence of IUF and cervical bacteria before and after mating. Mares were classified i...
Douwes RA, van der Kolk JH.The use of dimethyl sulphoxide in equine medicine is discussed with special reference to trauma of the central nervous system, chronic endometritis, trauma of the locomotor apparatus, and ischaemic bowel pathophysiology. The ability of dimethyl sulphoxide to reduce connective tissue formation might be of interest in abdominal surgery. The anti-inflammatory effect of dimethyl sulphoxide is used in the treatment of muscle trauma, tendinitis, laminitis, and arthritis. Dimethyl sulphoxide can potentiate the effects of other drugs. The most common dose is 1 g/kg body weight intravenously up to a 40...
Ferrer MS, Lyle SK, Paccamonti DL, Eilts BE, Hosgood G, Godke RA.Low-dose insemination has been proposed to reduce persistent breeding-induced endometritis (PBIE) in mares with delayed uterine clearance (DUC). Others proposed that hysteroscopic insemination induces an exaggerated inflammatory response and should be avoided in DUC mares. The objectives here were to evaluate presence and severity of PBIE in normal and DUC mares after hysteroscopic insemination with fresh semen, and to determine if hysteroscopy could be used in DUC mares without inducing excessive inflammation. Reproductively normal (n = 4) and DUC (n = 5) mares received four treatments in ran...
Nikolakopoulos E, Kindahl H, Watson ED.Mares resistant (n=7) and susceptible (n=9) to persistent mating-induced endometritis were artificially inseminated (AI) during oestrus with chilled extended semen. Blood samples were collected from 30 min before AI, for 2 h after AI and again between 16 and 18 h after AI. Samples were assayed for oxytocin and the PGF2alpha metabolite 13,14-dihydro-15-keto PGF2alpha (PGFM). AI caused a significant increase in oxytocin concentrations in both the resistant and susceptible mares and there was no significant difference in oxytocin release between the two groups of mares. Mean PGFM concentrations w...
Boyd EH, Allen WE.Plasma concentrations of neomycin were measured after intrauterine infusion of 3.3 mg/kg neomycin sulphate. Mares infected two hours previously with an intra-uterine infusion of beta-haemolytic streptococci absorbed approximately 12 per cent of the neomycin in both the oestrous and the luteal phases of the cycle. Normal mares in oestrus absorbed 6 per cent of the neomycin infused and luteal mares absorbed 56 per cent. In infected mares the peak plasma concentrations occurred two hours after neomycin infusion, earlier than in healthy mares. Cervical flushings after neomycin infusion in infected...
Scudamore CL, Pemberton AD, Miller HR, McDonnell AM, Thomson SR, Dawson A, Watson ED.An enzyme linked immunosorbent assay (ELISA) was developed and used to estimate the concentrations of the serine proteinase inhibitor, alpha-1 proteinase inhibitor (API), in uterine flushings recovered from mares at different stages of the oestrous cycle and before and after the induction of experimental endometritis. There was a significant increase in the concentrations of API and albumin relative to total protein in flushings recovered during oestrus compared with dioestrus but no difference was observed in the concentrations of these proteins relative to total protein before and after the ...
Hemberg E, Kindahl H, Lundeheim N, Einarsson S.The objectives of this study were to investigate: (i) relationships between early foal health and their dams' reproductive health at mating/conception as well as after parturition and (ii) health status during early foal life and its association with performance as an adult. The study included 35 foals showing clinical symptoms indicating septicaemia, sometimes in combination with other disturbances, within their first 18 h postpartum (Group I). Eighty-eight foals that were healthy during their first few days of life were used as control (Group II). All foals were born in the same region of Sw...
Woods GL, Hillman RB, Schlafer DH.To evaluate embryo transfer as a possible method to circumvent infertility in mares, embryos from 14 normal and 14 infertile mares were collected three times and examined. Fewer flushes (p less than 0.05) from normal than infertile mares (1/42 vs 9/42) contained only abnormal embryos whereas more flushes (p less than 0.05) from normal than infertile mares contained one or more normal embryos (28/42 vs 8/42). More flushes (p less than 0.05) from normal than infertile mares contained embryos (29/42 vs 17/42). The embryo diameters (mm) at either day-7 or day-8 post ovulation were greater (p less ...
Hakansson A, Albihn A, Magnusson U.The aim of the present study was to investigate if complement contributes to opsonic activity in the uterine secretions of mares with normal reproductive functions. Five mares with a mean age of 9 years were used in the study. The mares were considered to be free of endometritis based upon clinical history, palpation per rectum and ultrasonogaraphy of the genital tract, videoendoscopic inspection of the uterus, electronmicroscopy of endometrial biopsies, and bacteriological and cytological examination of swabs from the endometrium. The hormonal status of the mares was also determined. Uterine ...
Asif S, Umar T, Umar Z, Jamil H, Feng H, Zhang P, Umer S.Endometritis plays an important role in mare infertility. Certain infectious agents interfere with the innate immune system of endometrium, causing a systemic inflammatory response that lasts for a long time and circulates via the blood or cellular degeneration, leading to endometritis due to bacterial endotoxins. Different small, non-coding RNA molecules are involved in many biological functions. For instance, microRNAs (miRNAs) are involved in the post-transcriptional regulation of gene expression. These miRNAs are important regulators of gene expression, primarily via inhibiting transcripti...
Zhang X, Mai Z, Gao Y, Zhao X, Zhang Y.Endometritis is a common condition in mares that causes significant economic loss. Lacking obvious clinical signs, the clinical diagnosis of endometritis in mares relies on case-by-case clinical examinations, which can be particularly inefficient in large-scale farms. Therefore, the identification of potential biomarkers can serve as a non-invasive and efficient screening technique for endometritis in mares. Objective: To compare the blood proteome between fertile mares and mares with endometritis to identify biomarkers potentially associated with the development of endometritis and validate t...