Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Infection
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.
Equine herpes virus type 1 (EHV-1) infection induces alterations in the cytoskeleton of vero cells but not apoptosis. Effects of infection with two different strains of equine herpes virus type 1 (EHV-1; Piber 178/83, Kentucky D) on the cytoskeleton of Vero cells were investigated immunohistochemically, and evaluated by confocal laser scanning microscopy. Twenty four hours post EHV-1 infection the assembly of the microtubulus system of Vero cells was heavily disturbed. The Golgi region was dispersed into vesicles spread throughout the cytoplasm as demonstrated by WGA lectin binding. Other cytoskeletal elements such as cytokeratin, vimentin, and filamentous actin (F-actin) were not affected by EHV-1 infection....
Agonist-induced adherence of equine neutrophils to fibronectin- and serum-coated plastic is CD18 dependent. Adherence to vascular endothelium and extracellular matrix proteins is a pre-requisite for neutrophil accumulation at sites of inflammation. In this study, equine neutrophil adherence to fibronectin and autologous serum-coated plastic in response to PAF, hrIL-8, hrC5a and PMA has been measured. In addition, the mechanisms involved have been investigated using monoclonal antibodies (MoAbs) against the beta2 integrin CD18. PAF and hrC5a caused similar, concentration dependent, increases in adherence to fibronectin- and serum-coated plastic (maximum responses 19 +/- 4% and 19 +/- 3% for PAF and 1...
Isolates of fungi from symptomatic carthorses in Awassa, Ethiopia. Samples were collected from clinically infected carthorses in Awassa. Fungus species affecting the carthorses were identified. Eight genera of fungal groups were isolated from swabs and skin scrapes taken from symptomatic horses. These included Aspergillus spp., Histoplasma spp., Penicillium spp., Microsporum spp., Trichophyton spp., yeast cells of Candida spp., Cryptococcus spp. and Geotrichum spp. The most frequent isolates were from the genera Aspergillus (48%), Penicillium (39.2%) and Trichophyton (31.6%). Clinical findings are reported, the economic, zoonotic and pathogenetic importance o...
Predilection sites of Trichinella spiralis larvae in naturally infected horses. A total of 120 muscle tissues from three horses naturally infected with Trichinella spiralis were examined. The head was the most infected site. In particular, the muscles harbouring the highest number of larvae were: musculus buccinator (12, 411 and 1183 larvae g-1), the tongue (11, 615 and 1749 larvae g-1), m. levator labii maxillaris (17,582 and 1676 larvae g-1), and the masseter (4.9, 289 and 821 larvae g-1). Compared with the diaphragm, the number of larvae per gram was from 3.5 to 6.8 times higher in the tongue, from 3.5 to 6.5 higher in m. levator labii maxillaris, and from 2.5 to 4.6 h...
Cloning and expression of a 48-kilodalton Babesia caballi merozoite rhoptry protein and potential use of the recombinant antigen in an enzyme-linked immunosorbent assay. A cDNA expression library prepared from Babesia caballi merozoite mRNA was screened with a monoclonal antibody BC11D against the rhoptry protein of B. caballi merozoite. A cDNA encoding a 48-kDa protein of B. caballi was cloned and designated BC48. The complete nucleotide sequence of the BC48 gene had 1,828 bp and was shown to contain no intron. Southern blotting analysis indicated that the BC48 gene contained more than two copies in the B. caballi genome. Computer analysis suggested that this sequence contained an open reading frame of 1,374 bp with a coding capacity of approximately 52 kDa. ...
Vaccination against lyme disease with recombinant Borrelia burgdorferi outer-surface protein A (rOspA) in horses. Eight 1-year-old ponies were vaccinated with recombinant OspA (ospA gene derived from B. burgdorferi B31) with adjuvant (aluminium hydroxide). Four ponies were used as non-vaccinated controls with adjuvant. One hundred and twelve days after the first vaccination, the vaccinated and non-vaccinated ponies were challenged by exposure to B. burgdorferi-infected adults tick (Ixodes scapularis) collected from Westchester County, New York (tick infection rate >/=60%). Protection from infection was evaluated by culture for B. burgdorferi from three monthly skin biopsies taken near the site of tick ...
Characterization of a Sarcocystis neurona isolate (SN6) from a naturally infected horse from Oregon. An isolate of Sarcocystis neurona (SN6) was obtained from the spinal cord of a horse from Oregon with neurologic signs. The parasite was isolated in cultures of bovine monocytes and equine spleen cells. The parasite divided by endopolygeny and completed at least one asexual cycle in cell cultures in three days. Two gamma interferon knockout mice inoculated with cell culture-derived merozoites became ill 35 d later and S. neurona schizonts and merozoites were found in encephalitic lesions. The parasite in tissue sections of mice reacted with S. neurona-specific antibodies and S. neurona was rei...
Evaluation of iodophor skin preparation techniques and factors influencing drainage from ventral midline incisions in horses. To document natural bacterial flora on the ventral aspect of the equine abdomen, to compare 2 preparation techniques, and to identify potential risk factors that may contribute to incisional drainage. Methods: Prospective study. Methods: 53 horses undergoing exploratory celiotomy. Methods: Group-1 horses (n = 26) were prepared with povidone-iodine and alcohol. Group-2 horses (27) were prepared with a film-forming iodophor complex. Numbers of bacterial colony-forming units (CFU) were measured before and after surgical scrub, following skin closure, and after recovery from general anesthesia. Sw...
Factors associated with prognosis for survival and athletic use in foals with septic arthritis: 93 cases (1987-1994). To identify factors affecting the prognosis for survival and athletic use in foals with septic arthritis. Methods: Retrospective study. Methods: 93 foals with septic arthritis. Methods: Medical records were reviewed to obtain clinical findings, laboratory test results, radiographic findings, treatment method, and outcome. Race records for Thoroughbreds and Standardbreds were evaluated to determine whether foals subsequently raced and whether they raced successfully. Results: 43 foals had 1 affected joint, 44 foals had multiple affected joints, and number of affected joints was not recorded for...
An experimental evaluation of methods used to enumerate mucosal cyathostome larvae in ponies. With the increased interest in equine cyathostomes it has become apparent that some evaluations of methods currently used to count the various larval stages which occur in the mucosa would be beneficial. Experiments were conducted to investigate the effects of fixation and storage of mucosal tissues at -20 C on the accuracy of counting these larvae. The accuracy of counting developing larvae within the mucosa by transmural illumination (TMI) and by artificial digestion (DIG) of the mucosa was also compared. The data indicate that fixation of digested mucosa in PBS-buffered 5% or 10% formalin d...
Salmonella Abortusequi strains of equine origin harbor a 95kb plasmid responsible for virulence in mice. Most Salmonella choleraesuis subsp. choleraesuis serovar Abortusequi strains of equine origin harbor a 95kb plasmid, pSA95. Results of PCR and Southern blot analysis suggest that pSA95 contains spv genes. A pSA95-cured strain of S. Abortusequi was 48 times less virulent to mice than its parental strain. Virulence was restored by reintroduction of pSA95. These results provide clear evidence that pSA95 confers virulence on S. Abortusequi in mice. This is the first report describing a virulence plasmid of S. Abortusequi.
Determination of equid herpesvirus 1-specific, CD8+, cytotoxic T lymphocyte precursor frequencies in ponies. The frequency of antigen-specific, genetically restricted cytotoxic T lymphocyte precursors (CTLp) was measured in peripheral blood mononuclear cells (PBMC) of ponies before and after infection with equid herpesvirus 1 (EHV1). Split-well limiting dilution analysis (LDA) was developed to measure CTLp frequency using EHV1-infected 51Cr-labelled lymphoblasts as targets. Extensive characterisation showed that recombinant human interleukin-2, autologous antigen presenting cells and equine serum containing virus neutralising antibody were necessary for maturation of CTLp into effector CTL in vitro. ...
Clinical, haematological and biochemical findings in foals with neonatal Equine herpesvirus-1 infection compared with septic and premature foals. A retrospective multicentre study comparing historical, clinical, haematological, acid-base and biochemical findings of foals with Equine herpesvirus-1 (EHV-1) infection, septicaemia or prematurity was performed to determine if early diagnosis of EHV-1 foals was possible. Fifty-three foals were studied and were assigned to one of 2 groups: herpes positive (n = 14) or herpes negative (n = 39). The latter group included 20 septic, 11 premature, and 8 premature and septic foals. The presence of herpes antigen was confirmed by immunoperoxidase histochemical staining of tissues from necropsied foal...
Comparison of the pathogenesis of acute equine herpesvirus 1 (EHV-1) infection in the horse and the mouse model: a review. The mouse models of the respiratory and abortion forms of equine herpesvirus 1 (EHV-1) infection have been used to investigate the vaccine potential of various EHV-1 immunogens, the effect of antiviral agents on EHV-1 infection and the pathogenicity of EHV-1 strain variants and deletion or insertional mutants. This review examines the similarities and differences in the pathogenesis of primary EHV-1 infection in the natural host, the horse, and in the mouse by comparing tissue tropism, clinical signs of infection, the effects of EHV-1 on pregnancy, haematological changes following infection, v...
Epidemiological studies of equine herpesvirus 1 (EHV-1) in Thoroughbred foals: a review of studies conducted in the Hunter Valley of New South Wales between 1995 and 1997. Sero-epidemiological studies conducted between 1995 and 1997 on two large Thoroughbred stud farms in the Hunter Valley of NSW showed clear evidence of EHV-1 infection in foals as young as 30 days of age. Similarly, serological evidence suggested that these foals were infected with EHV-1 from their dams or from other lactating mares in the group, with subsequent foal to foal spread of infection prior to weaning. These studies also provided evidence of EHV-1 infection of foals at and subsequent to weaning, with foal to foal spread of EHV-1 amongst the weanlings. These data indicated that the mar...
Epidemiology of EHV-1 and EHV-4 in the mare and foal populations on a Hunter Valley stud farm: are mares the source of EHV-1 for unweaned foals. The prevalence of EHV-1 and EHV-4 antibody-positive horses was determined using a type specific ELISA on serum samples collected from 229 mares and their foals resident on a large Thoroughbred stud farm in the Hunter Valley of New South Wales in February 1995. More than 99% of all mares and foals tested were EHV-4 antibody positive, while the prevalence of EHV-1 antibody positive mares and foals were 26.2 and 11.4%, respectively. Examination of the ELISA absorbance data for the individual mares and foals suggested that the EHV-1 antibody positive foals had been infected recently with EHV-1 and...
Endothelial cell infection in vivo by equine infectious anaemia virus. Equine infectious anaemia virus (EIAV) infection of horses is characterized clinically by recurrent episodes of fever, thrombocytopenia and anaemia. In vivo, the only site of virus replication that has been previously demonstrated for EIAV is the tissue macrophage. In this study, in situ hybridization for EIAV was combined with immunohistochemistry for cell-type-specific markers to identify infected endothelial cells. EIAV-infected endothelial cells and macrophages were detected in horses infected with either virulent wild-type or with weakly virulent tissue culture-adapted strains of EIAV. Th...
Potential of DNA-mediated vaccination for equine herpesvirus 1. The potential of DNA-mediated immunisation to protect against equine herpesvirus 1 (EHV-1) disease was assessed in a murine model of EHV-1 respiratory infection. Intramuscular injection with DNA encoding the EHV-1 envelope glycoprotein D (gD) in a mammalian expression vector induced a specific antibody response detectable by two weeks and maintained through 23 weeks post injection. Immune responses were proportional to the dose of DNA and a second injection markedly enhanced the antibody response. EHV-1 gD DNA-injected mice developed neutralising antibodies, and a predominance of IgG2a antibod...
Tumor necrosis factor and interleukin-6 activity and endotoxin concentration in peritoneal fluid and blood of horses with acute abdominal disease. The purpose of this study was to evaluate the diagnostic and prognostic significance of tumor necrosis factor-alpha (TNF) and interleukin-6 (IL-6) activities and endotoxin concentration in blood and peritoneal fluid of 155 adult horses with acute abdominal disease (colic). Samples also were obtained from 20 healthy adult horses. Blood and peritoneal fluid supernatant TNF and IL-6 activities and endotoxin concentration were significantly greater in horses with colic, compared with healthy horses. In horses with colic, the peritoneal fluid endotoxin concentration and TNF and IL-6 activities were...
Actinobacillus lignieresii infection in two horses. A 10-year-old pregnant Norwegian Fjord horse was examined for gross swelling of the muzzle of 2 years' duration. Examination of biopsy specimens revealed diffuse dermal fibrosis, micropustule formation, and vascular thrombosis; large numbers of Actinobacillus lignieresii were isolated in pure culture. Prolonged treatment with i.v. administration of sodium iodide and oral administration of trimethoprim-sulfamethoxazole caused regression of the swelling and did not induce abortion. A 5-month-old American Paint filly was examined for swelling in the udder region. Bacteriologic culture of purulent...
Inter-relationship between Gasterophilus larvae and the horse’s gastric and duodenal wall with special reference to penetration. The degree of penetration into the stomach and duodenum of the horse by bot fly larvae, Gasterophilus intestinalis (De Geer) and G. nasalis (Linnaeus) (Diptera : Gasterophilidae) was evaluated. Evidence of larval perforation of the stomach or duodenum was not found on gross inspection. Palpation of the intact stomach and duodenum was not effective in establishing the existence of Gasterophilus larvae within the organs. Findings suggest that larvae of both species produce an ulcer of similar depth within the gastrointestinal wall. The ulcer depth produced by larvae did not correlate with the no...
Natural variation of equine infectious anemia virus Gag protein cytotoxic T lymphocyte epitopes. Two defined cytotoxic T lymphocyte (CTL) epitopes from equine infectious anemia virus (EIAV)-infected horses, equine leukocyte alloantigen (ELA)-A5.1-restricted epitope 18a, and ELA-A9-restricted epitope 28b-1 were evaluated for conservation among three wild-type EIAV strains. Epitope 18a variation occurred in all three wild-type EIAV strains, while epitope 28b-1 varied in one strain. Further, 12% amino acid changes occurred in the Gag proteins of a recently isolated wild-type strain, documenting a much greater Gag protein variation than previously reported. Evaluation of epitope 18a among two...
Jejunoileal incarceration and strangulation through a splenic defect in a mare. A 6-year-old, standardbred mare was presented for colic of 12 h duration. Transrectal palpation revealed intestinal distension of unknown cause. The mare was euthanized. At necropsy, segmental jejunoileal incarceration and strangulation through an opening in the spleen was observed. This opening was considered to be a congenital defect.
Modulation of cytokine response of pneumonic foals by virulent Rhodococcus equi. The ability of Rhodococcus equi to induce pneumonia in foals depends on the presence of an 85- to 90-kb plasmid. In this study, we evaluated whether plasmid-encoded products mediate virulence by modulating the cytokine response of foals. Foals infected intrabronchially with a virulence plasmid-containing strain of R. equi had similar gamma interferon (IFN-gamma) and interleukin-12 (IL-12) p35 but significantly higher IL-1beta, IL-10, IL-12 p40, and tumor necrosis factor alpha (TNF-alpha) mRNA expression in lung tissue compared to foals infected with the plasmid-cured derivative. IFN-gamma mRNA...
Erythrocyte associated haemato-biochemical changes in Babesia equi infection experimentally produced in donkeys. Equine babesiosis, caused by Babesia equi and transmitted by ticks is of major economic importance in India. The adverse effects which B. equi organism and its metabolites inflict on red blood cells have not been reported. Erythrocytes were analysed for red cell membrane phospholipids, proteins and haemoglobin (Hb) concentration and plasma for malondialdehyde (MDA) in B. equi carrier donkeys before splenectomy (50% parasitaemia. Before splenectomy the mean values of membrane protein, phospholipids, plasma MDA and Hb were found to be 1.63 +/- 0.12 mg/ml PCV, 2.28 +/- 0.9 mg/ml PCV, 3.63 +/- 0.3...
Cyathostominae (Nematoda) parasites of Equus caballus in some Brazilian states. Thirty six horses from nine Brazilian states (Goiás, Minas Gerais, Pará, Maranhão, Piauí, Paraíba, Pernambuco, Rio Grande do Norte, and Ceará) were examined for infections by small strongyles. The following species were identified: Cylicocyclus nassatus, C. insigne, C. brevicapsulatus, C. leptostomum, C. radiatus, C. ultrajectinus, C. ashworthi, Cylicostephanus goldi, C. calicatus, C. minutus, C. longibursatus, Petrovinema poculatum, Coronocyclus coronatus, C. labiatus, C. labratus, Cyathostomum catinatum, C. pateratum, C. alveatum, Parapoteriostomum euproctus, Cylicodontophorus bicorona...
Seroepizootiological survey of Japanese encephalitis virus and Getah virus in regional horse race tracks from 1991 to 1997 in Japan. A sero-epizootiological survey was conducted for Japanese encephalitis virus (JEV) and Getah virus (GeV) at 10 to 20 regional horse race tracks from 1991 to 1997 in Japan. It was observed that geometrical mean (GM) antibody titer to JEV and GeV was 10 to 50 times higher than others at several race courses (RCs) almost every year. Of them, several race horses showing high antibody titer, which were suggested to be infected with the virus, were also observed in this survey. These data suggested that the viruses have spread among race horses almost every year in Japan, although, fortunately, no h...
