Infections in horses encompass a range of diseases caused by various pathogens, including bacteria, viruses, fungi, and parasites. These infections can affect different systems within the horse, such as the respiratory, gastrointestinal, and integumentary systems, leading to a variety of clinical signs depending on the pathogen and the severity of the infection. Common infectious diseases in horses include equine influenza, strangles, and equine herpesvirus. Diagnosis often involves clinical examination, laboratory testing, and sometimes imaging, to identify the causative agent and assess the extent of the disease. Treatment strategies may include antimicrobial therapy, supportive care, and preventive measures such as vaccination and biosecurity practices. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment, and prevention of infectious diseases in equine populations.
Retteg Pauls S, Jottini S, Takai S, Venner M, Wohlsein P.A 3-month-old female trotter foal was euthanized due to severe dyspnoea. Pathomorphologically a chronic granulomatous to necrotizing pneumonia was found and Rhodoccocus (R.) equi was isolated microbiologically. An immunohistological method using a murine monoclonal antibody against a 15-17 kDa antigen of virulent R. equi was established in formalin-fixed and paraffin-embedded tissue sections using various antigen retrieval techniques to optimize the staining results. Microwave treatment was most suitable for the demonstration of bacterial antigen localized predominantly in intralesional macrop...
Rohdich N, Zschiesche E, Heckeroth A, Wilhelm C, Leendertse I, Thomas E.A multicentre field study was conducted in accordance with VICH Guideline on Good Clinical Practice (VICH 2000) to confirm the efficacy and safety of a new formulation of cefquinome for the treatment of naturally occurring severe bacterial infections and septicaemia in foals. Thirty-nine foals suffering from severe bacterial infections (such as pneumonia, gastro-enteritis, arthritis, omphalitis, or wound infections) or acute septicaemia were treated twice daily with the test product (1 mg cefquinome/kg body weight) intravenously for three days and then intramuscularly for three to 11 days. Inv...
Liu M, Liu T, Bordin A, Nerren J, Cohen N.Toll-like receptor 9 (TLR9) activation stimulates protective immune responses against intracellular pathogens by phagocytes, including neutrophils. This study examined TLR9-mediated neutrophil activation in neonatal foals. Unmethylated CpGs, ligands for TLR9, were used to stimulate equine neutrophils, either purified or in contact with other peripheral blood leukocytes. Rhodococcus equi was used as another stimulus in parallel. TLR9 mRNA was constitutively expressed at a similar level in purified equine neutrophils across different ages from birth to adulthood, and expression was not affected ...
Bright LA, Burgess SC, Chowdhary B, Swiderski CE, McCarthy FM.The horse genome is sequenced, allowing equine researchers to use high-throughput functional genomics platforms such as microarrays; next-generation sequencing for gene expression and proteomics. However, for researchers to derive value from these functional genomics datasets, they must be able to model this data in biologically relevant ways; to do so requires that the equine genome be more fully annotated. There are two interrelated types of genomic annotation: structural and functional. Structural annotation is delineating and demarcating the genomic elements (such as genes, promoters, and ...
Ryu SH, Koo HC, Park YK, Kim JM, Jung WK, Davis WC, Park YH, Lee CW.Equine respiratory disease is a common cause of poor performance and training interruptions. The higher incidence rate of infectious upper respiratory disease (IURD) in thoroughbred racehorses at the Seoul Race Park coincided with the frequent stabling season, shorter stabling periods, and younger ages in this study. Incidence rates were also correlated with significantly lower proportions of cells expressing MHC class II-, CD2 antigen-, CD4+- or CD8+-T lymphocyte-, and B lymphocyte in IURD patients compared with healthy control groups in the summer and fall and in 2-and-3-year-old groups. The...
Tamarit A, Gutierrez C, Arroyo R, Jimenez V, Zagalá G, Bosch I, Sirvent J, Alberola J, Alonso I, Caballero C.An outbreak of Trypanosoma evansi infection that occurred in mainland Spain is described. The outbreak occurred on an equine and camel farm to which dromedary camels from an infected area of the Canary Islands had recently been introduced. One of these camels developed clinical signs and T. evansi was discovered in a blood smear examination. The herd was evaluated in order to determine the extent of the disease. The results showed that 76% of the camels, 35% of the donkeys and 2% of the horses were affected. The animals were isolated and treated using Cymelarsan((R)) (0.5mg/kg). After treatmen...
Guimarães-Ladeira CV, Palhares MS, Oliveira JS, Ramirez MA, Guedes RM.Proliferative enteropathy, caused by the intracellular bacterium Lawsonia intracellularis, has been described in horses in Australia, the USA, Canada and European countries but has not been reported in Latin America. The prevalence of the disease in horses worldwide is unknown. Objective: To evaluate the presence of subclinical L. intracellularis infection in horses in the state of Minas Gerais, Brazil. Methods: A longitudinal study using serology and PCR for detecting antibodies (IgG) and shedding of L. intracellularis in faecal samples, respectively, was conducted using a total of 223 horses...
Grinberg A, Pomroy WE, Carslake HB, Shi Y, Gibson IR, Drayton BM.To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study. Methods: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for...
Santín M, Vecino JA, Fayer R.This is the first report of Enterocytozoon bieneusi in an equid species. Feces from 195 horses from 4 locations in Colombia were examined for E. bieneusi by polymerase chain reaction. Of these, 21 horses (10.8%) were found positive for E. bieneusi . The prevalence of E. bieneusi in horses 1 yr of age (2.5%). No significant differences in prevalence were observed between male (13.7%) and female horses (9%). Sequencing of the internal transcribed spacer region of the SSUrRNA locus identified 3 genotypes. Two genotypes appear to be unique to horses and were named Horse 1 and Horse 2. A third geno...
Ellison S, Witonsky S.Sarcocystis neurona is the principal etiologic agent of equine protozoal myeloencephalitis (EPM). An immunodominant protein of S. neurona, SnSAG-1, is expressed by the majority of S. neurona merozoites isolated from spinal tissues of horses diagnosed with EPM and may be a candidate for diagnostic tests and prophylaxis for EPM. Five horses were vaccinated with adjuvanted recombinant SnSAG1 (rSnSAG1) and 5 control (sham vaccinated) horses were vaccinated with adjuvant only. Serum was evaluated pre- and post-vaccination, prior to challenge, for antibodies against rSnSAG1 and inhibitory effects on...
Reuss SM, Chaffin MK, Cohen ND.To describe frequency, types, and clinical outcomes of extrapulmonary disorders (EPDs) in foals in which Rhodococcus equi infection was diagnosed, and to identify factors determined at the time of admission that differentiated foals that developed EPDs from foals with R equi infection identified only in the lungs. Methods: Retrospective case series. Methods: 150 foals aged 3 weeks to 6 months with a diagnosis of R equi infection. Methods: Medical records were reviewed for information on date of admission, signalment, history, clinical signs, diagnostic testing, treatment, duration of hospitali...
Konishi E.The literature on natural infections with Japanese encephalitis virus in Japan and subclinical:clinical infection rates was summarized. To detect natural infections, conventional serologic methods were used in the past, while nonstructural 1 protein-based methods have been used recently. Annual infection rates in humans and horses indicated the status of natural virus activity in Japan.
Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM.Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both loc...
Corning S.The small strongyles of horses, also known as cyathostomins, are considered the most prevalent and pathogenic parasites of horses today. The clinical syndrome of larval cyathostominosis which occurs as a result of mass emergence of inhibited stages has a high fatality rate despite the best standard of care given to affected horses. Management of the challenge level of cyathostomins to prevent the syndrome is preferable. Many different management programmes have been tried over the past two decades, with mixed success. Programmes have relied heavily on repeated use of anthelmintic treatments th...
von Samson-Himmelstjerna G, Traversa D, Demeler J, Rohn K, Milillo P, Schurmann S, Lia R, Perrucci S, di Regalbono AF, Beraldo P, Barnes H, Cobb R....For the control of worm infections, the strategic use of anthelmintics, often accompanied by additional farm and/or pasture management procedures, is currently applied on most horse farms in industrialized countries. However, the particular effects of the specific worm control procedures are often unclear and have only been investigated to a limited extent. We examined faecal egg count (FEC), faecal egg count reduction (FECR) and questionnaire data on farm and pasture management procedures. The aim of this study was to determine whether specific worm control practices reported to be applied in...
Lake SL, Matthews JB, Kaplan RM, Hodgkinson JE.Genetic resistance against benzimidazole (BZ) anthelmintics is widespread in cyathostomins, the commonest group of intestinal parasitic nematodes of horses. Studies of BZ-resistant nematodes of sheep, particularly Haemonchus contortus, have indicated that an anthelmintic resistance-conferring T/A polymorphism, encoding an F (phenylalanine) to Y (tyrosine) substitution, in beta-tubulin isotype 1 is present at two loci, codons 167 and 200 (F167Y, F200Y). Recent studies using complementary (c) DNA derived from BZ-susceptible and -resistant cyathostomins identified statistical differences in the f...
Dantas-Torres F.The objective of this article was to discuss some aspects of ticks associated with domestic animals in the State of Pernambuco, northeastern Brazil, based on a literature review and present new data obtained from recent tick collections carried out in this northeastern Brazilian state. From August 2007 to June 2008, 1,405 ticks were collected and five species were identified: Amblyomma cajennense (Fabricius, 1787), Amblyomma ovale Koch, 1844, Dermacentor nitens Neumann, 1897, Rhipicephalus (Boophilus) microplus (Canestrini, 1887), and Rhipicephalus sanguineus (Latreille, 1806). Dogs from urban...
Schaffartzik A, Weichel M, Crameri R, Björnsdóttir TS, Prisi C, Rhyner C, Torsteinsdóttir S, Marti E.Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of Culicoides and sometimes Simulium spp. The aim of this investigation was to identify Simulium allergens associated with IBH. A phage surface display cDNA library expressing recombinant Simulium vittatum salivary gland proteins was screened using sera of IBH-affected horses sensitized to S. vittatum salivary gland proteins as shown in immunoblot, resulting in the identification of seven cDNAs encoding IgE-binding proteins. The deduced amino acid sequences of these proteins showed sequence similarities to a...
Gao X, Jiang CG, Han XE, Zhao LP, Shen RX, Xiang WH, Zhou JH.To elucidate the function of the S2 gene in equine infectious anemia virus (EIAV) and its role in the attenuation of the Chinese attenuated EIAV vaccine strains, the S2 in the EIAV vaccine strain EIAV (FDDV) was reverse-mutated and the in vitro replication character of the resultant virus was evaluated. Based on the sequence variation of the S2 gene between the EIAV virulent strains and vaccine strains, all the four vaccine-specific sites in the S2 of an EIAV(FDDV) infectious clone, pFDDV3-8, were reverse-mutated to the sequences of the virulent strain EIAV(DV115). The reverse-mutated molecula...
Woldehiwet Z.Anaplasma phagocytophilum is the recently designated name replacing three species of granulocytic bacteria, Ehrlichia phagocytophila, Ehrlichia equi and the agent of human granulocytic ehrlichiosis, after the recent reorganization of the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales. Tick-borne fever (TBF), which is caused by the prototype of A. phagocytophilum, was first described in 1932 in Scotland. A similar disease caused by a related granulocytic agent was first described in horses in the USA in 1969; this was followed by the description of two distinct granulocy...
Guss B, Flock M, Frykberg L, Waller AS, Robinson C, Smith KC, Flock JI.Streptococcus equi subspecies equi (S. equi) is a clonal, equine host-adapted pathogen of global importance that causes a suppurative lymphodendopathy of the head and neck, more commonly known as Strangles. The disease is highly prevalent, can be severe and is highly contagious. Antibiotic treatment is usually ineffective. Live attenuated vaccine strains of S. equi have shown adverse reactions and they suffer from a short duration of immunity. Thus, a safe and effective vaccine against S. equi is highly desirable. The bacterium shows only limited genetic diversity and an effective vaccine coul...
Swinburne JE, Bogle H, Klukowska-Rötzler J, Drögemüller M, Leeb T, Temperton E, Dolf G, Gerber V.Recurrent airway obstruction (RAO), or heaves, is a naturally occurring asthma-like disease that is related to sensitisation and exposure to mouldy hay and has a familial basis with a complex mode of inheritance. A genome-wide scanning approach using two half-sibling families was taken in order to locate the chromosome regions that contribute to the inherited component of this condition in these families. Initially, a panel of 250 microsatellite markers, which were chosen as a well-spaced, polymorphic selection covering the 31 equine autosomes, was used to genotype the two half-sibling familie...
Pusterla N, Byrne BA, Hodzic E, Mapes S, Jang SS, Magdesian KG.A quantitative real-time (RT)-PCR assay was developed to detect Salmonella spp. in the feces of 911 equine species admitted to a veterinary hospital. Fresh feces and feces enriched for 24h in selenite broth were assessed by conventional culture and by RT-PCR targeting the Salmonella invA gene. The detection limit for the RT-PCR assay was 3 and 10 organisms, respectively, when spiked samples were purified from selenite broth and feces. The analytical specificity was 100% based on the detection of a panel of 40 salmonella serotypes from five serogroups and the lack of cross-reactivity with non-r...
Fortier G, van Erck E, Pronost S, Lekeux P, Thiry E.Equine gammaherpesviruses (γEHV) have been widely studied over the past 45 years and many isolates have been characterised. Despite this, the diagnosis of γEHV infection remains difficult to establish as its clinical manifestations lack specificity, ranging from mild respiratory signs in a small number of animals to outbreaks in large groups of young horses. This review focuses on the epidemiology, pathogenesis, clinical manifestations and diagnosis of equine herpesvirus (EHV)-2 and -5 infections, as well as on the genetic variation of these viruses. Study of these variations has resulted in...
Pearce JW, Giuliano EA, Moore CP.To evaluate and compare the in vitro susceptibility of Aspergillus and Fusarium spp. isolated from horses with ulcerative keratomycosis, address regional differences in equine keratomycosis isolates, and provide susceptibility data to update prior studies. Methods: Fourteen horses with ulcerative keratomycosis. Methods: Banked fungal isolates from equine corneal ulcers (eight Aspergillus spp. and six Fusarium spp.) were identified at The University of Texas Health Science Center at San Antonio. In vitro minimum inhibitory concentration and susceptibility to natamycin, fluconazole, itraconazole...
Stewart AJ, Salazar T, Waldridge BM, Schumacher J, Welles EG, Hanson RR, Sartin EA, Lenz SD, Holland M, Beard DM.A 7-year-old 509-kg (1,120-lb) Tennessee Walking Horse mare was evaluated because of bilateral mucosanguinous nasal discharge, intermittent right-sided epistaxis, and worsening dyspnea of 9 months' duration. Results: Multiple masses in the nasopharynx were detected via endoscopic and radiographic examinations. Cytologic and histologic examinations of biopsy specimens of 1 mass revealed round yeasts with thick nonstaining capsules and occasional narrow-based budding that resembled cryptococcal organisms. Results: Oral administration of fluconazole and organic ethylenediamine dihydriodide and in...
Müller N, Welle M, Lobsiger L, Stoffel MH, Boghenbor KK, Hilbe M, Gottstein B, Frey CF, Geyer C, von Bomhard W.The present report describes a novel etiological agent of cutaneous leishmaniasis in horses that, at least for some cases, sporadically appeared as autochthonous infections in geographically distant regions of Germany and Switzerland. The infection was initially diagnosed upon clinical and immunohistological findings. Subsequent comparative sequence analysis of diagnostic PCR products from the internal transcribed spacer 1 (ITS1) of ssrRNA classified the respective isolates as neither Old World nor New World Leishmania species. However, four isolates subjected to molecular analyses all exhibit...
Carslake HB.Three horses were presented with facial swelling and epiphora. Results: All horses had facial swellings and radiographic findings consistent with exostosis at the lacrimomaxillary suture, and ipsilateral epiphora. Positive contrast dacryocystorhinography demonstrated that the site of obstruction of the nasolacrimal duct was located where the duct traverses the lacrimomaxillary suture. Methods: Lacrimomaxillary suture exostosis. Conclusions: Lacrimomaxillary suture exostosis should be considered as a differential diagnosis in cases of epiphora in horses. Dacryocystorhinography, preferably retro...
Muñoz-Prieto A, Escribano D, Contreras-Aguilar MD, Horvatić A, Guillemin N, Jacobsen S, Cerón JJ, Mrljak V.The aim of this study was to investigate the changes in the salivary proteome in horses with acute abdominal disease (AAD) using a tandem mass tags (TMT)-based proteomic approach. The saliva samples from eight horses with AAD were compared with six healthy horses in the proteomic study. Additionally, saliva samples from eight horses with AAD and eight controls were used to validate lactoferrin (LF) in saliva. The TMT analysis quantified 118 proteins. Of these, 17 differed significantly between horses with AAD and the healthy controls, 11 being downregulated and 6 upregulated. Our results showe...
Murphy B, Bell C, Koehne A, Dubielzig RR.Odontoameloblastoma (OA) is a mixed odontogenic tumor that is an ameloblastoma with concurrent histologic evidence of odontoma differentiation. As a mixed tumor, OA is a tripartite lesion comprised of neoplastic odontogenic epithelium, induced dental ectomesenchyme (dental pulp), and mineralized dental matrix. Although rare, OA represents a diagnostic conundrum, as it is histologically closely related to 2 other mixed odontogenic tumors: odontoma (complex and compound) and ameloblastic fibro-odontoma. Herein we describe an OA arising from the mandible of a 4-mo-old Fischer 344 rat that had bee...
Husebekk A, Husby G, Sletten K, Marhaug G, Nordstoga K.Amyloid was extracted from the liver of a horse that had developed amyloidosis after being used for several years for the production of antibodies to bacterial antigens. The amyloid fibrils were shown to be of the AA type. Two AA proteins with molecular weights of 9000 and 11,000 and with identical partial N-terminal amino acid sequences were identified. Marked structural homology with AA from other species including man was seen, although clear species-related antigenic specificity was observed. SAA isolated from an acute phase (septic abortion) horse serum was identical to AA with respect to...
Witte TS, Bergwerff AA, Scherpenisse P, Drillich M, Heuwieser W.Endometritis is one of the major problems in the horse breeding industry. The use of antibiotics for treatment of endometritis in the mare is recommended as best practice. The intrauterine application of antibiotics, however, has been under discussion over the last years because of concerns about its efficacy. The systemic use of antibiotics has been considered more effective because of its better distribution within the uterus. The objective of the present study was to determine the concentration of ceftiofur derivates in serum and endometrial tissue after intramuscular administration. Specif...
Schumacher J, Vaughan JT.Treatments of penile and preputial injuries, anomalies, tumors, "summer sores," paraphimosis, phimosis, and priapism are presented. Surgical procedures described include preputiotomy, reefing, penile retraction, amputation, and relocation. Treatment of hemospermia by means of urethrotomy is discussed.
Frazier K, Liggett A, Hines M, Styer E.We describe a fatal case of mushroom intoxication in an 18-y-o horse presumably due to Amanita verna. Horses are normally regarded as too fastidious to eat the ill-flavored toadstools. In this case, the horse had a rare benign brain tumor, meningioangiomatosis, which may have altered the horse's normal eating behavior resulting in consumption of the mushrooms.
Kelmer G, Tatz A, Bdolah-Abram T.To describe indwelling cephalic or saphenous vein catheter use for intravenous regional limb perfusion (ID-IV-RLP) to treat horses with synovial injury (contamination/infection) of the distal aspect of the limb. Methods: Retrospective case series. Methods: Horses (n = 44; 45 limbs) treated with proximal ID-IV-RLP. Methods: Horses had ID-IV-RLP using a cephalic (21 limbs) or saphenous (24 limbs) vein. Amikacin was the most frequently used antibiotic. Number of perfusions ranged from 3 to 21 (median 7). A cast was applied to 14 injured limbs (1 tube cast, 1 full-limb cast, 2 foot casts, and 10 h...
Cholleti H, Paidikondala M, Munir M, Hakhverdyan M, Baule C.Equine arteritis virus (EAV) causes a respiratory and reproductive disease in horses, equine viral arteritis. Though cell death in infection with EAV is considered to occur by apoptosis, the underlying molecular mechanism has not been extensively elucidated. We investigated the expression of mRNA of pro-apoptotic and caspase genes during EAV infection in BHK21 cells, a well-established cell type for EAV replication. Using a SYBR Green real-time PCR, mRNA of p53, Bax, caspase 3 and caspase 9 were found up-regulated in a time dependent manner in EAV infected cells. Western blot analysis for casp...
Love S, Burden FA, McGirr EC, Gordon L, Denwood MJ.Domesticated grazing animals including horses and donkeys are frequently housed using deep litter bedding systems, where it is commonly presumed that there is no risk of infection from the nematodes that are associated with grazing at pasture. We use two different approaches to test whether equids could become infected with cyathostomines from the ingestion of deep litter straw bedding. Two herbage plot studies were performed in horticultural incubators set up to simulate three straw bedding scenarios and one grass turf positive control. Faeces were placed on 16 plots, and larval recoveries pe...
Lew AM, Thomas LM, Huntington PJ.Sera of sixteen horses with clinical signs of EIA from six different outbreaks and sera of 100 uninfected horses were used to validate an ELISA for EIA diagnosis. The antigen used was a recombinant protein derived from the amino-terminal portion of the transmembrane envelope protein of EIA (gp45). Reactivity between positive and negative sera could be clearly distinguished. Comparison with the traditional agar gel immunodiffusion test (commonly called the Coggins test) showed that the ELISA was superior in sensitivity. Comparison of this ELISA with the FAST-ELISA system showed that the latter ...
Keller M, Krehon S, Stanek C, Rosengarten R.Specimens of hoof horn from 187 horses were examined for a possible relationship between clinically affected hooves and the occurrence of pathogenic fungi. Specimens were taken from the coronary band and from the stratum externum and medium of the coronary horn and transferred on to Sabouraud dextrose agar, with and without cycloheximide, and incubated at 28 degrees C. Dermatophytes and mould fungi were identified by their macroscopic and microscopic characteristics. The 732 isolates could be assigned to 26 species of moulds, two different species of the dermatophyte Microsporum and three diff...
Hollis AR.Sarcoids are the most common cutaneous neoplasm of the horse, arising as a result of a neoplastic proliferation of fibroblasts associated with infection with bovine papillomavirus, most notably types 1 and 2. Although they do not metastasise, they are locally invasive and aggressive, and can lead to important welfare concerns, interfere with tack and therefore impede athleticism, and undoubtedly lead to a reduction in the value of affected horses. This review discusses the evidence behind the most commonly used treatments for equine sarcoids. The most commonly used treatments are discussed. No...
Burger NC, Nesvadba J, Nesvadba Z, Busato A, Gottstein B.A cross-sectional field study on the prevalence of Dicrocoelium dendriticum was performed in the Emmental. The study included 211 bovines, 170 equines, 20 ovines, 46 caprines and 23 rabbits (from 119 farms). In addition, laboratory routine diagnostic data obtained from 2.840 animals--all originating from the same area of investigation--were assessed in the same way. The infection extent concerning the different animal species were the following: bovines 46%, equines 12%, ovines 30%, caprines 48% and rabbits 9%. Univariate analyses of baseline epidemiological data identified no significant risk...
Parkinson NJ, Buechner-Maxwell VA, Witonsky SG, Pleasant RS, Werre SR, Ahmed SA.The innate immune response to lipopolysaccharide contributes substantially to the morbidity and mortality of gram-negative sepsis. Horses and humans share an exquisite sensitivity to lipopolysaccharide and thus the horse may provide valuable comparative insights into this aspect of the inflammatory response. MicroRNAs, small non-coding RNA molecules acting as post-transcriptional regulators of gene expression, have key roles in toll-like receptor signaling regulation but have not been studied in this context in horses. The central hypothesis of this study was that lipopolysaccharide induces di...