Pathogens are microorganisms, such as bacteria, viruses, fungi, and parasites, that can cause disease in horses. These microorganisms interact with the equine immune system, often leading to a range of health issues that can affect individual horses or entire populations. Pathogens can be transmitted through various routes, including direct contact, vectors, or environmental exposure. Common equine pathogens include Streptococcus equi, Equine Herpesvirus, and Strongylus vulgaris. Understanding the interactions between equine hosts and pathogens is essential for disease prevention, management, and treatment. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, transmission, and impact of pathogens on equine health.
Hrala M, Andrla P, Bosák J, Fedrová P, Mugutdinov A, Karpíšková R, Nedbalcová K, Raichová J, Faldyna M, Hořín P, Šmajs D.Taylorella equigenitalis is the causative agent of sexually transmitted contagious equine metritis. Infections manifest as cervicitis, vaginitis and endometritis and cause temporary infertility and miscarriages of mares. While previous studies have analyzed this organism for various parameters, the evolutionary dynamics of this pathogen, including the emergence of antibiotic resistance, remains unresolved. The aim of this study was to isolate contemporary strains, determine their genome sequences, evaluate their antibiotic resistance and compare them with other strains. We determined nine comp...
Benitez-Ibalo AP, Debárbora VN, Mangold AJ, Nava S, Sebastian PS.After the previous description and characterization of Theileria equi sensu stricto (Genotype A) in Argentina, the aim of the present study was to investigate the possible heterogeneity of 18 S rDNA genotypes circulating in this country. Therefore, blood samples from 18 horses from two different neighborhoods of Corrientes City, Corrientes Province, were analyzed for infection with Theileria species. Theileria DNA was detected in five samples (27.8%). Four nearly complete 18 S rDNA gene sequences were obtained and phylogenetic analyses were carried out. The maximum likelihood tree constructe...
Equine infectious anemia virus (EIAV) is the simplest described within the family, related to the human immunodeficiency viruses (HIV-1 and HIV-2). There is an important interplay between host cells and viruses. Viruses need to hijack cellular proteins for their viral cycle completion and some cellular proteins are antiviral agents interfering with viral replication. HIV cellular partners have been extensively studied and described, with a special attention to host proteins able to inhibit specific steps of the viral cycle, called restriction factors. Viruses develop countermeasures against ...
Smith MZ, York M, Townsend KS, Martin LM, Gull T, Coghill LM, Ericsson AC, Johnson PJ.Whereas restoration of fecal consistency after treatment with clioquinol for chronic diarrhea and free fecal water syndrome has been attributed to its antiprotozoal properties, actions of clioquinol on the colonic bacterial microbiota have not been investigated. Objective: Characterize the dynamics of fecal microbial diversity before, during, and after PO administration of clioquinol to healthy horses. Methods: Experimental prospective cohort study using a single horse group. Methods: Eight healthy adult horses received PO clioquinol (10 g, daily) for 7 days. Feces were obtained daily for ...
Egli P, Boone L, Huber L, Higgins C, Gaonkar PP, Arrington J, Naskou MC, Peroni J, Gordon J, Lascola KM.Platelet lysate (PL) demonstrates antimicrobial and anti-inflammatory properties offering potential for treatment of bacterial pneumonia in horses. It remains unknown whether nebulization is suitable for PL administration in horses. This pilot study characterized particle size and flow rate of pooled equine PL (single preparation) nebulized using an equine-specific nebulizer (Flexivent®). Unassigned: Protein composition and antimicrobial activity were compared before and after nebulization. Protein composition was evaluated according to growth factor, antimicrobial peptide and cytokine concen...
Haenni M, Châtre P, Drapeau A, Cazeau G, Troncy J, François P, Madec JY.Enterobacter hormaechei is an important pathogen in humans and animals, which, in addition to its intrinsic AmpC, can acquire a wide variety of genes conferring resistances to extended-spectrum cephalosporins (ESCs) and carbapenems (CPs). In France, human clinical outbreaks of E. hormaechei resistant to ESC or carbapenem were reported. Objective: To study E. hormaechei isolates from cats and dogs (=59) as well as from horses (n = 55) presenting a non-susceptible phenotype to beta-lactams in order to determine which clones, resistance genes and plasmids are circulating in France. Methods: E. ho...
Padalino B, Pellegrini F, Felici M, Zappaterra M, Catella C, Cordisco M, Lorusso E, Cirone F, Pratelli A.Respiratory disorders (RDs) are a common transport-related welfare consequence in horses. This prospective study described the journeys of horses transported to two slaughterhouses in Italy, documented the prevalence of potentially RD-related pathogens, and identified possible predisposing factors. Data were recorded from arrival until 48 h after arrival and included the collection of Deep Nasopharyngeal Swabs (DNS), journey details and welfare assessment of horses (n = 155). PCR was used to quantify the presence of influenza A virus, reovirus, equine herpesvirus type 1 and 4, adenovirus, r...
Jung C, Gentil M, Müller E.The objective of the study was to investigate the age dependent occurrence of different infectious agents in foals with diarrhea. Methods: Fecal samples, which were submitted to a commercial laboratory for a PCR-profile "Foal Diarrhea Pathogens" from 01.01.2021 up to 31.12.2022 (n=144), were examined for Equine Coronavirus (ECoV), , (), toxin-encoding genes , , , and , toxin-encoding genes and , as well as Rotavirus A via PCR. Results: Pathogens could be detected in a high proportion (42.9%) of the samples. Rotavirus A was the most prevalent pathogen in the current study, followed by clos...
Chhabra D, Nagra J, Manuja A, Singha HS, Vaid RK, Goutam U, Kumar B. poses a significant threat to equine health globally. The bacteria causes strangles, a respiratory disease characterized by enlarged, abscessed lymph nodes, leading to airway obstruction. The bacterium, a Gram-positive, chain-forming, Lancefield group C β-hemolytic , is closely related to and distinction between these species is challenging. The present study focused on characterization of isolates from horses in northern India, aiming at elucidation of their sugar fermentation patterns. Nasal and nasopharyngeal swabs collected from different geographical regions of northern India, yieldin...
Hain-Saunders N, Knight DR, Bruce M, Riley TV.Recent increases in community-associated Clostridioides difficile infections have highlighted the importance of monitoring toxigenic C. difficile from animal and environmental sources. We provide the complete circularized genomes of two toxigenic C. difficile strains isolated from feral horse faeces. Genome N64 (sequence type 964) consists of a single chromosome of 4,078,791 bp, while genome H251 (sequence type 963) comprises one chromosome (4,304,722 bp) and three plasmids (150,942 bp, 11,534 bp, and 9,074 bp).
Mazzei M, Sorvillo B, Sgorbini M, Bindi F, Perelli A, Laus F.(1) Background: Respiratory problems may be associated with pathogens among which viruses may play an important role in causing or promoting clinical signs. However, traditional diagnostic methods for equine infectious diseases, such as PCR, are limited to known pathogens and often miss rare or novel viruses. Metagenomic next-generation sequencing is a transformative method that allows the sequencing of all genomes present in a sample. Recent studies have used next-generation sequences to identify viral sequences in horses with unexplained respiratory symptoms, revealing potential links betwee...
Mazzei M, Sorvillo B, Sgorbini M, Bindi F, Perelli A, Laus F.(1) Background: Respiratory problems may be associated with pathogens among which viruses may play an important role in causing or promoting clinical signs. However, traditional diagnostic methods for equine infectious diseases, such as PCR, are limited to known pathogens and often miss rare or novel viruses. Metagenomic next-generation sequencing is a transformative method that allows the sequencing of all genomes present in a sample. Recent studies have used next-generation sequences to identify viral sequences in horses with unexplained respiratory symptoms, revealing potential links betwee...
Migdał A, Migdał Ł, Oczkowicz M, Tombarkiewicz B, Okólski A.Colostrum contains substances such as hormones, enzymes, polyamides, nucleic acid derivatives, and amino acid derivatives and also includes immunomodulating substances, proline-rich polypeptides, immunoglobulins (Ig) as well as bacteriostatic compounds. The aim of the study was to evaluate the impact of colostral Ig on the level of expression of selected Toll-like receptor genes (TLR3, TLR4, and TLR7). The experiments were conducted on 25 Polish Pony foals. Blood samples were collected according to the following scheme: before first suckling, at the 1st, 3rd, 5th, 10th, 20th, and 30th, day of ...
Cheong SH, Franklin-Guild R, Goodman LB, Lago-Alvarez Y, Lee YL, de Aguiar LH, de Amorim MD, Altier C.Fungal and bacterial culture is currently the primary method for pathogen detection and identification. Next-generation sequencing is a powerful method for detecting and identifying the presence of microbial DNA in samples. We evaluated the correlation between fungal and bacterial culture with next-generation sequencing in equine uterine samples. Fungal cultures (n=63) were evaluated based on their culture results. In culture positive (n=16) samples, next-generation sequencing identified the same organism in 10 samples (62.5%), 5 samples did not identify fungal agents, and 1 sample identified ...
Scupham AJ, Tong C.In 2018, a new virus, named equine parvovirus-hepatitis (EqPV-H), was discovered in a biologic product that had been administered to horses that subsequently developed clinical signs of equine serum hepatitis (Theiler disease). Further correlation of the virus with the disease sparked federal requirements that all equine biologics be free of EqPV-H. The initial quantitative real-time PCR (qPCR) test for EqPV-H has proved to be sensitive to co-extracted PCR inhibitors in template nucleic acids, causing false-negative results. We investigated the use of digital PCR (dPCR) as a more robust test. ...
Ryu SH, Jang B, Kim BS, Park KT.This is the first report describing the isolation and genome sequence of Flavobacterium ceti (F. ceti IJFC025) from a draining submandibular lymph node abscess in a 6-year-old mixed-breed mare in Korea. Since F. ceti is not a usual infectious pathogen that causes equine health problems, this study presents the complete genome sequence of F. ceti isolated from a submandibular lymph node abscess sample in Jeju, South Korea, in 2022. The entire genome sequence of F. ceti IJFC025 consisted of a 3,144,426-bp chromosome with 35.6 % G + C content. Gene prediction revealed that this strain possesse...
Köhne M, Hüsch R, Tönissen A, Schmidt M, Müsken M, Böttcher D, Hirnet J, Plötz M, Kittler S, Sieme H. subspecies (subsp.) is an important facultative pathogen in horses and can cause severe infections in other species including humans. Facing the post-antibiotic era, novel antimicrobials are needed for fighting bacterial infections. Bacteriophages (phages) are the natural predators of bacteria and discussed as a promising antimicrobial treatment option. The objective of this study was to isolate and characterize subsp. specific phages for the first time and to evaluate their efficacy and . In total, 13 phages with lytic activity were isolated and host ranges were determined. Two phages wit...
Sasaki M, Fukumoto N, Fukumoto S.A two-year-old male Japanese draft horse (known as a "Ban'ei horse") excreted eight cestodes. Based on their morphological features, they were identified as Anoplocephala perfoliata. The partial mitochondrial cytochrome c oxidase subunit 1 (COI) sequences of the worms were nearly identical to A. perfoliata isolated from horses in Europe. The results of phylogenetic analyses of COI revealed that our samples and the European isolates formed the same clade, which was separate from Chinese and Australian isolates. Ban'ei horses were developed by crossbreeding draft horses imported from European co...
Haywood LMB, Sheahan BJ.Equine colitis is a devastating disease with a high mortality rate. Infectious pathogens associated with colitis in the adult horse include Clostridioides difficile, Clostridium perfringens, Salmonella spp., Neorickettsia risticii/findlaynesis, and equine coronavirus. Antimicrobial-associated colitis can be associated with the presence of infectious pathogens. Colitis can also be due to non-infectious causes, including non-steroidal anti-inflammatory drug administration, sand ingestion, and infiltrative bowel disease. Current treatments focus on symptomatic treatment (restoring fluid and elect...
Fahey MJ, Harman RM, Thomas MA, Pugliese BR, Peters-Kennedy J, Delco ML, Van de Walle GR.We aimed to study the antimicrobial and pro-healing potential of equine mesenchymal stromal cell secreted products (i.e. secretome), collected as conditioned media (mesenchymal stromal cell-conditioned media, MSC CM), in a novel in vivo model of methicillin-resistant Staphylococcus aureus (MRSA)-inoculated equine thorax wounds. Methods: Prospective in vivo study. Methods: Two Thoroughbred geldings. Methods: Six full-thickness cutaneous wounds were created bilaterally on the dorsal thorax of two horses (n = 12 wounds/horse). Wounds on the left thoraces were inoculated with MRSA on day 0. Al...
Samir A, Abdel-Moein KA, Zaher HM.The upsurge of diarrheagenic E. coli pathotypes carrying extended-spectrum beta-lactamases (ESBLs)/plasmid-mediated AmpC β-lactamase (pAmpC) among animals constitutes an emerging threat for humans and animals. This study investigated the burden of ESBL-/pAmpC-producing diarrheagenic E. coli among diarrheic foals and its potential public health implications. Rectal swabs were collected from 80 diarrheic foals. These swabs were processed to isolate and identify ESBL/pAmpC-producing E. coli using a selective culture medium, biochemical tests, phenotypic identification, and molecular identificati...
de Albuquerque CV, da Silva Andrade M, de Freitas MS, Paulino PG, Santos HA, de Tarso Landgraf Botteon P.Equine Piroplasmosis (EP) and Equine Granulocytic Anaplasmosis (EGA) are diseases that affect horses, transmitted by ixodid ticks, causing a nonspecific febrile syndrome. Equine Piroplasmosis is endemic in Brazil, and most horses are in enzootic stability. Serological and molecular studies carried out on horses in Brazil have shown the presence of Anaplasma phagocytophilum, however, the clinical relevance of this infection has not yet been established. The present study aims to evaluate the importance of Babesia caballi, Theileria equi, and A. phagocytophilum as etiological agents in horses wi...
Ochi A, Toya Y, Sengoku M, Tsuchiya S, Kishi D, Ueno T.Equine piroplasmosis (EP) is a protozoal disease affecting equids, caused by and . EP is conventionally diagnosed using microscopic, molecular, and/or serological methods, which are time-consuming. Consequently, there is a need for faster testing methods. In this study, we evaluated the application of the Sysmex XN-31 automated hematology analyzer, originally a rapid test for detecting malaria in humans, for the diagnosis of EP. The cultured parasites were measured using the XN-31 that had been customized for horse blood samples (XN-31m). The following parameters were evaluated: limit of dete...
Mizuguchi Y, Tsuzuki N, Ebana MD, Suzuki Y, Kakuda T. is an intracellular bacterium that causes suppurative pneumonia in foals. T-helper (Th) 1 cells play an important role in the protective response against . In mice and humans, the directionality of IgG switching reflects the polarization of Th-cell responses, but this has not been fully elucidated in horses. In this 4-year study, we classified -infected foals into surviving and non-surviving group and investigated differences in IgG subclass response to virulence-associated protein A, the main virulence factor of , between the groups. IgGa, IgGb, and IgG(T) titers were significantly higher in...
Tyrnenopoulou P, Tsilipounidaki K, Florou Z, Gkountinoudis CG, Tyropoli K, Starras A, Peleki C, Marneris D, Arseniou N, Lianou DT, Katsarou EI....The objectives of this study were (a) to detect zoonotic gastrointestinal pathogens in faecal samples of horses using the FilmArray GI Panel and (b) to identify variables potentially associated with their presence. Faecal samples collected from 224 horses obtained during a countrywide study in Greece were tested by means of the BioFire FilmArray Gastrointestinal (GI) Panel, which uses multiplex-PCR technology for the detection of 22 pathogens. Gastrointestinal pathogens were detected in the faecal samples obtained from 97 horses (43.3%). Zoonotic pathogens were detected more frequently in samp...
Lawrence KE, Gedye K, Carvalho L, Wang B, Fermin LM, Pomroy WE.To determine whether evidence for infection with (Ikeda) could be identified in samples of commercial red deer , horses, and working farm dogs in New Zealand. Unassigned: Blood samples were collected during October and November 2019 from a convenience sample of red deer (n = 57) at slaughter. Equine blood samples (n = 50) were convenience-sampled from those submitted to a veterinary pathology laboratory for routine testing in January 2020. Blood samples, collected for a previous study from a convenience sample of Huntaway dogs (n = 115) from rural regions throughout the North and ...
Ramsay L, Eberhardt C, Schoster A.Reports of leptospirosis in horses are limited. Objective: To describe the clinical and diagnostic findings of acute systemic leptospirosis in horses. Methods: Eleven client-owned horses presented to an equine hospital because of acute onset of disease between 2015 and 2023. Methods: Retrospective case series. Horses diagnosed with leptospirosis by 1 or more of urine PCR, serologic microscopic agglutination test (MAT), and histopathology. Results: Common clinical signs included lethargy (10), anorexia (10), fever (9), tachypnea (9), abnormal lung sounds (9), and epistaxis (6). Acute kidney inj...
Anandu S, Tanuj GN, Vijayasarathi MK, Manjusha KM, Samanta S, Bandyopadhyay S, Sankar M.Ocular setariasis is an ectopic infection caused by a parasite under the genus Setaria. Adult worms belong to the Setariidae family and typically reside in the peritoneal cavity of ungulates. However, immature forms of these species may aberrantly migrate to the eyes of cattle, buffalo, goats, horses and several other hosts, leading to corneal opacity and blindness. Here, we have distinguished the Setaria digitata collected from both equine and buffalo hosts based on the morphology, molecular profiling of mitochondrial cytochrome c oxidase subunit 1 (Cox1), cytochrome c oxidase subunit 3 (Cox3...
Campos AS, Franco AC, Godinho FM, Huff R, Candido DS, da Cruz Cardoso J, Hua X, Claro IM, Morais P, Franceschina C, de Lima Bermann T, Dos Santos FM....Western equine encephalitis virus (WEEV) is a mosquitoborne virus that reemerged in December 2023 in Argentina and Uruguay, causing a major outbreak. We investigated the outbreak using epidemiologic, entomological, and genomic analyses, focusing on WEEV circulation near the Argentina‒Uruguay border in Rio Grande do Sul state, Brazil. During November 2023‒April 2024, the outbreak in Argentina and Uruguay resulted in 217 human cases, 12 of which were fatal, and 2,548 equine cases. We determined cases on the basis of laboratory and clinical epidemiologic criteria. We characterized 3 fatal equ...
Hietala SK, Ardans AA.The interaction of Rhodococcus equi with alveolar macrophages from adult horses, foals experimentally exposed to R. equi (sensitized foals) and non-exposed foals was studied using in vitro bactericidal assays, cytochemical staining and transmission electron microscopy. It was demonstrated that R. equi is a facultative intracellular parasite, able to survive and multiply within the alveolar macrophages of the host by interfering with phagosome-lysosome fusion. Opsonization of R. equi with antibody against capsular components was associated with increased phagosome-lysosome fusion and significan...
Erol E, Locke SJ, Donahoe JK, Mackin MA, Carter CN.The goal of this retrospective study was to have a comprehensive picture of the β-hemolytic streptococci of horses including tissue/organ distributions and susceptibility patterns against specific antimicrobials between January 1, 2000 and December 31, 2010. A total of 2,497 β-hemolytic streptococci were isolated from 2,391 cases, of which Streptococcus equi subsp. zooepidemicus was the most frequent isolate (72.0%). Other species isolated were Streptococcus dysgalactia subsp. equisimilis (21.3%), Streptococcus equi subsp. equi (5.8%), and unidentified β-hemolytic streptococci (0.9%). As ex...
Dubey JP, Howe DK, Furr M, Saville WJ, Marsh AE, Reed SM, Grigg ME.Equine protozoal myeloencephalitis (EPM) is a serious disease of horses, and its management continues to be a challenge for veterinarians. The protozoan Sarcocystis neurona is most commonly associated with EPM. S. neurona has emerged as a common cause of mortality in marine mammals, especially sea otters (Enhydra lutris). EPM-like illness has also been recorded in several other mammals, including domestic dogs and cats. This paper updates S. neurona and EPM information from the last 15 years on the advances regarding life cycle, molecular biology, epidemiology, clinical signs, diagnosis, treat...
Oladunni FS, Oseni SO, Martinez-Sobrido L, Chambers TM.Equine influenza virus (EIV) is a constantly evolving viral pathogen that is responsible for yearly outbreaks of respiratory disease in horses termed equine influenza (EI). There is currently no evidence of circulation of the original H7N7 strain of EIV worldwide; however, the EIV H3N8 strain, which was first isolated in the early 1960s, remains a major threat to most of the world's horse populations. It can also infect dogs. The ability of EIV to constantly accumulate mutations in its antibody-binding sites enables it to evade host protective immunity, making it a successful viral pathogen. C...
Greay TL, Oskam CL, Gofton AW, Rees RL, Ryan UM, Irwin PJ.Ticks are among the most important vectors of pathogens affecting companion animals, and also cause health problems such as tick paralysis, anaemia, dermatitis, and secondary infections. Twenty ixodid species have previously been recorded on dogs, cats, and horses in Australia, including Rhipicephalus sanguineus, Ixodes holocyclus and Haemaphysalis longicornis, which transmit tick-borne diseases. A survey of hard ticks (Acari: Ixodidae) was conducted during 2012-2015 to investigate tick species that infest dogs, cats, and horses in Australia. Individual tick specimens were collected from dogs,...
M'ghirbi Y, Yaïch H, Ghorbel A, Bouattour A.Anaplasma phagocytophilum , the causative agent of granulocytic anaplasmosis, affects several species of wild and domesticated mammals, including horses. We used direct and indirect methods to compare and evaluate exposure to A. phagocytophilum in horses in northern Tunisia. Methods: Serum from 60 horses was tested by IFA for antibodies to A. phagocytophilum , and whole blood was tested for A. phagocytophilum 16S rRNA gene using a nested-PCR. To examine the risk of A. phagocytophilum transmission, 154 ticks that had been collected from horses were examined for the presence of A. phagocytophilu...
Lüthje P, Schwarz S.In this study, erythromycin- and/or clindamycin-resistant isolates among 248 coagulase-positive and coagulase-variable staphylococci and 500 streptococci, collected all over Germany during 2004-2006 in the resistance monitoring program BfT-GermVet, were investigated for their genetic basis of macrolide and/or lincosamide resistance. Staphylococci were sampled from various disease conditions of dogs/cats or pigs, whereas streptococci were from dogs/cats, pigs or horses. Resistant staphylococci were further identified biochemically to species and subspecies level and tested for the resistance ge...
Hansford KM, Carter D, Gillingham EL, Hernandez-Triana LM, Chamberlain J, Cull B, McGinley L, Paul Phipps L, Medlock JM.During September 2018, a tick was submitted to Public Health England's Tick Surveillance Scheme for identification. The tick was sent from a veterinarian who removed it from a horse in Dorset, England, with no history of overseas travel. The tick was identified as a male Hyalomma rufipes using morphological and molecular methods and then tested for a range of tick-borne pathogens including; Alkhurma virus, Anaplasma, Babesia, Bhanja virus, Crimean-Congo Haemorrhagic fever virus, Rickettsia and Theileria. The tick tested positive for Rickettsia aeschlimannii, a spotted fever group rickettsia li...
Ladrón N, Fernández M, Agüero J, González Zörn B, Vázquez-Boland JA, Navas J.The actinomycete Rhodococcus equi is an important pathogen of horses and an emerging opportunistic pathogen of humans. Identification of R. equi by classical bacteriological techniques is sometimes difficult, and misclassification of an isolate is not uncommon. We report here on a specific PCR assay for the rapid and reliable identification of R. equi. It is based on the amplification of a fragment of the choE gene encoding cholesterol oxidase. The choE-based PCR was assessed by using a panel of strains comprising 132 isolates from different sources and of different geographical origins, all i...
Takai S, Ohbushi S, Koike K, Tsubaki S, Oishi H, Kamada M.The prevalence of virulent Rhodococcus equi in isolates from soil and feces of foals on a farm with endemic R. equi infections was significantly higher than that of a farm with no history of the disease. Foals bred on a farm with the endemic disease might be constantly exposed to virulent R. equi in their environment.
Busscher JF, van Duijkeren E, Sloet van Oldruitenborgh-Oosterbaan MM.Two hundred healthy horses housed at 23 different farms and one clinic and 42 persons in close contact with these horses were screened for the presence of methicillin resistant staphylococci. Samples were taken from the nose and the pastern of the horses and from the nose and throat of the humans and incubated in selective media. Isolates were identified by standard techniques and their susceptibilities were tested using an agar diffusion method. Methicillin-resistant strains were tested for the presence of the mecA gene by PCR. In 45 horses (22.5%) and 15 humans (35.7%) mecA positive staphylo...
Milinovich GJ, Trott DJ, Burrell PC, Croser EL, Al Jassim RA, Morton JM, van Eps AW, Pollitt CC.Carbohydrate-induced laminitis in horses is characterized by marked changes in the composition of the hindgut microbiota, from a predominantly Gram-negative population to one dominated by Gram-positive bacteria. The objective of this study was to monitor changes in the relative abundance of selected hindgut bacteria that have previously been implicated in the pathophysiology of equine laminitis using fluorescence in situ hybridization (FISH). Caecal cannulae were surgically implanted in five Standardbred horses and laminitis induced by oral administration of a bolus dose of oligofructose. Caec...
Silaghi C, Liebisch G, Pfister K.Equine Granulocytic Anaplasmosis (EGA) is caused by Anaplasma phagocytophilum, a tick-transmitted, obligate intracellular bacterium. In Europe, it is transmitted by Ixodes ricinus. A large number of genetic variants of A. phagocytophilum circulate in nature and have been found in ticks and different animals. Attempts have been made to assign certain genetic variants to certain host species or pathologies, but have not been successful so far. The purpose of this study was to investigate the causing agent A. phagocytophilum of 14 cases of EGA in naturally infected horses with molecular methods o...
Estep LK, McClure CJ, Burkett-Cadena ND, Hassan HK, Hicks TL, Unnasch TR, Hill GE.Eastern equine encephalitis virus (EEEV) is a mosquito-borne pathogen that cycles in birds but also causes severe disease in humans and horses. We examined patterns of avian host use by vectors of EEEV in Alabama from 2001 to 2009 using blood-meal analysis of field-collected mosquitoes and avian abundance surveys. The northern cardinal (Cardinalis cardinalis) was the only preferred host (fed on significantly more than expected based on abundance) of Culiseta melanura, the enzootic vector of EEEV. Preferred hosts of Culex erraticus, a putative bridge vector of EEEV, were American robin (Turdus ...
Bruhn O, Grötzinger J, Cascorbi I, Jung S.Antimicrobial peptides play a pivotal role as key effectors of the innate immune system in plants and animals and act as endogenous antibiotics. The molecules exhibit an antimicrobial activity against bacteria, viruses, and eukaryotic pathogens with different specificities and potencies depending on the structure and amino-acid composition of the peptides. Several antimicrobial peptides were comprehensively investigated in the last three decades and some molecules with remarkable antimicrobial properties have reached the third phase of clinical studies. Next to the peptides themselves, numerou...
Gold JJ, Heath IB, Bauchop T.Vegetative and reproductive stages of Caecomyces equi gen. nov., sp. nov. isolated from the horse caecum were examined by light and electron microscopy. This organism, which is similar to isolates known as Sphaeromonas communis, produces uniflagellate, uninucleate zoospores whose perikinetosomal structures, i.e. circumflagellar ring, spur, struts and scoop, are similar in many respects to those described in species of Neocallimastix. Microtubular roots extend basally from the spur and associate with hydrogenosomes and the nucleus. Another group of microtubules radiates laterally in a fan-shape...
Oyarzun-Ampuero F, Vidal A, Concha M, Morales J, Orellana S, Moreno-Villoslada I.The treatment of skin wounds represents an important research area due to the important physiological and aesthetic role of this tissue. During the last years, nanoparticles have emerged as important platforms to treat skin wounds. Silver, gold, and copper nanoparticles, as well as titanium and zinc oxide nanoparticles, have shown potential therapeutic effects on wound healing. Due to their specific characteristics, nanoparticles such as nanocapsules, polymersomes, solid lipid nanoparticles, and polymeric nanocomplexes are ideal vehicles to improve the effect of drugs (antibiotics, growth fact...
de Jong NWM, Vrieling M, Garcia BL, Koop G, Brettmann M, Aerts PC, Ruyken M, van Strijp JAG, Holmes M, Harrison EM, Geisbrecht BV, Rooijakkers SHM.Staphylococcus aureus is a versatile pathogen capable of causing a broad range of diseases in many different hosts. S. aureus can adapt to its host through modification of its genome (e.g. by acquisition and exchange of mobile genetic elements that encode host-specific virulence factors). Recently, the prophage φSaeq1 was discovered in S. aureus strains from six different clonal lineages almost exclusively isolated from equids. Within this phage, we discovered a novel variant of staphylococcal complement inhibitor (SCIN), a secreted protein that interferes with activation of the human complem...
Yager JA.The pathogenesis of Rhodococcus equi pneumonia in foals is reviewed. The main routes of infection are respiratory and alimentary. The latter is probably the chief route of exposure in all foals and probably leads to development of specific immunity. Susceptible foals, those whose maternal immunity wanes before generation of their own immune response, readily develop disease if exposed aerogenously to sufficient numbers of R. equi. Management and environmental circumstances have a major role to play in determining the magnitude of this challenge and, therefore, in the prevalence of the disease....
Jensen-Jarolim E, Pacios LF, Bianchini R, Hofstetter G, Roth-Walter F.Owners and their domestic animals via skin shedding and secretions, mutually exchange microbiomes, potential pathogens and innate immune molecules. Among the latter especially lipocalins are multifaceted: they may have an immunomodulatory function and, furthermore, they represent one of the most important animal allergen families. The amino acid identities, as well as their structures by superposition modeling were compared among human lipocalins, hLCN1 and hLCN2, and most important animal lipocalin allergens, such as Can f 1, Can f 2 and Can f 4 from dog, Fel d 4 from cats, Bos d 5 from cow's...
Journal of medical entomologyDecember 9, 2008
Volume 45, Issue 6 1152-1155 doi: 10.1603/0022-2585(2008)45[1152:tobcbd]2.0.co;2
Schwint ON, Knowles DP, Ueti MW, Kappmeyer LS, Scoles GA.The tropical horse tick, Dermacentor nitens, is a natural vector of Babesia caballi in the Americas. B. caballi, one of the etiologic agents of equine piroplasmosis, occurs widely throughout the world, but the United States and a few other countries are considered to be free of infection. B. caballi is transovarially transmitted by the one-host tick D. nitens; we tested the hypothesis that B. caballi can persist in multiple generations of D. nitens in the absence of opportunity to reacquire infection from a susceptible equine host. Partially engorged female D. nitens were collected from a B. c...
Flickinger EA, Van Loo J, Fahey GC.Inulin and oligofructose are prebiotic oligosaccharides fermented in the large intestine. This article provides an extensive review of the effects of these oligosaccharides on gastrointestinal characteristics (microflora, pathogen control, epithelial cell proliferation, putrefactive compound production, fecal characteristics, and nutrient digestibility) and systemic metabolism of carbohydrates, nitrogen, lipids, and minerals in dogs, cats, horses, calves, pigs, poultry, and rabbits. In addition, intake of inulin and oligofructose and considerations in their supplementation to animal diets are ...
Grooters AM, Gee MK.Pythium insidiosum is an important cause of cutaneous and gastrointestinal disease in horses and dogs in the southeastern United States. Culture-based diagnosis of pythiosis is rarely definitive because production and identification of reproductive structures is difficult. The purpose of this study was to develop a polymerase chain reaction (PCR)-based assay for the identification of P insidiosum. Genomic DNA was extracted from 3 clinical isolates of P insidiosum and I isolate each of Pythium graminicola and Pythium arrhenomanes. The ITS I region of the ribosomal RNA gene of each isolate was a...
Snyder SP, England JJ, McChesney AE.Five of six immunodeficient Arabian foals that died of adenoviral infection were found to be infected with an intestinal coccidian of the genus Cryptosporidium. Various developmental stages of the organism were found in the microvillous border of the intestinal mucosa. The foals had diarrhea but it was not possible to separate the effects of the cryptosporidial infection from those of the concomitant adenoviral enteritis.
Ciscotto P, Machado de Avila RA, Coelho EA, Oliveira J, Diniz CG, Farías LM, de Carvalho MA, Maria WS, Sanchez EF, Borges A, Chávez-Olórtegui C.Venoms from the bee Apis mellifera, the caterpillar Lonomia achelous, the spiders Lycosa sp. and Phoneutria nigriventer, the scorpions Tityus bahiensis and Tityus serrulatus, and the snakes Bothrops alternatus, Bothrops jararaca, Bothrops jararacussu, Bothrops moojeni, Bothrops neuwiedi, Crotalus durissus terrificus, and Lachesis muta were assayed (800mug/mL) for activity against Staphylococcus aureus. Venoms from B. jararaca and B. jararacussu showed the highest S. aureus growth inhibition and also against other Gram-positive and Gram-negative bacteria. To characterize the microbicidal compon...
Baek S, Maloney JG, Molokin A, George NS, Cortés Vecino JA, Santin M. is a common intestinal protist in humans and animals worldwide. Wild and domestic animals are thought to be reservoirs of subtypes that also infect humans. There are limited studies on the prevalence and subtype distribution of in horses. In this study, 185 fecal samples were collected from horses (1 month to 17 years of age) in four regions of Colombia (Sabana de Bogotá, Costa Atlántica, Llanos Orientales, and Bogotá D.C.). presence and subtypes were determined by PCR and next generation amplicon sequencing. Eighty-one (43.8%) horses were positive for , with positive horses in all four...
Lewis GE, Huxsoll DL, Ristic M, Johnson AJ.Dogs (German Shepherd Dogs and Beagles), cates, rhesus macaques (Macaca mulatta), and baboons (Papio anubis) were inoculated with Whrlichia equi, the etiologic agent of equine ehrlichiosis. Within 3 to 7 days after inoculation, morulae were observed in the eosinophils of cats, neurtrophils of macaques and baboons, and in both neutrophils and eosinophils of dogs. The severe disease produced in horses by this agent was not a feature of E equi infection in dogs, cats, macaques, and baboons. However, a susceptible horse, inoculated with the pooled blood of 2 infected macaques, developed severe cli...
Risseti RM, Zastempowska E, Twarużek M, Lassa H, Pantoja JCF, de Vargas APC, Guerra ST, Bolaños CAD, de Paula CL, Alves AC, Colhado BS....Trueperella pyogenes is an opportunistic pathogen that causes diverse pyogenic infections in livestock. The genes that encode the exotoxin pyolysin (plo) and other putative factors that promote adhesion of pathogen to host cells (fimbriae fimA, fimC, fimE, fimG, neuraminidases nanH, nanP, and collagen-binding protein cbpA) have been associated with virulence, particularly in mastitis and uterus infections of dairy cows. However, the role of these virulence markers in the pathogenicity of the agent in domestic animals infections still is incompletely understood. The genes plo, fimA, fimC, fimE,...
Scholtzek AD, Hanke D, Walther B, Eichhorn I, Stöckle SD, Klein KS, Gehlen H, Lübke-Becker A, Schwarz S, Feßler AT.The detection of borderline oxacillin-resistant (BORSA) represents a challenge to both, veterinary and human laboratories. Between 2015 and 2017, 19 equine with elevated minimal inhibitory concentrations for oxacillin were detected in routine diagnostics. The aim of this study was to characterize these isolates to identify factors possibly associated with the BORSA phenotype. All were subjected to antimicrobial susceptibility testing and whole genome sequencing (WGS). A quantifiable β-lactamase activity assay was performed for a representative subset of 13 isolates. The WGS data analysis o...
Iwatani S, Zendo T, Yoneyama F, Nakayama J, Sonomoto K.A novel bacteriocin, lacticin Z, produced by Lactococcus lactis QU 14 isolated from a horse's intestinal tract was identified. Lacticin Z was purified through a three step procedure comprised of hydrophobic-interaction, cation-exchange chromatography, and reverse-phase HPLC. ESI-TOF MS determined the molecular mass of lacticin Z to be 5,968.9 Da. The primary structure of lacticin Z was found to consist of 53 amino acid residues without any leader sequence or signal peptide. Lacticin Z showed homology to lacticin Q from L. lactis QU 5, aureocin A53 from Staphylococcus aureus A53, and mutacin BH...
