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.
Dubey JP, Desmonts G.SEROLOGICAL and parasitological surveys indicate that Toxoplasma gondii infection is widely prevalent in horses (Riemann et a! 1975). To study the pathogenesis of orally-induced toxoplasmosis, 13 equids aged between Aix months and 13 years (nine ponies, three horses and one mule) were each inoculated orally with 10,000 oocysts of the GT-I strain of TRondii. The equids were killed 33 to 476 days after inoculation and their tissues were bioassaycd for T gondit (Dubey 1985). Details of inoculation, housing, clinical response and parasitological and histological findings were previously reported (...
Bernard W, Divers TJ, Whitlock RH, Messick J, Tulleners E.Clostridium botulinum and type-B C botulinum toxin were isolated from a necrotic wound that developed subsequent to castration in a 2-year-old Thoroughbred gelding. The horse had clinical signs of botulism and was successfully treated with wound debridement, C botulinum type-B antitoxin, potassium penicillin, and supportive care.
Magnuson NS, Perryman LE, Wyatt CR, Mason PH, Talmadge JE.Peripheral blood mononuclear cells from foals with hereditary severe combined immunodeficiency (SCID) have morphologic characteristics of large granular lymphocytes (LGL). Attempts to demonstrate cytotoxic activity were without success unless the LGL were incubated with 100 U of human recombinant interleukin 2 (rIL 2)/ml for 24 hr. With rIL 2 incubation, low effector to target ratios (10:1) consistently yielded high levels of cytotoxic activity (30 to 50%) in a standard 4-hr 51Cr-release assay using YAC-1 lymphoma or K562 erythroleukemia cell lines as targets. Monoclonal antibody EqT12 reacted...
Sedgwick AD, Dawson J, Lees P.Subpopulations of equine leucocytes, polymorphonuclear and mononuclear cells, were separated from whole blood on a discontinuous Percoll gradient and used in studies of chemokinesis and chemotaxis. Polymorphonuclear cells responded to the chemo-attractant properties of zymosan-activated plasma in Boyden chamber and agarose microdroplet assays but they responded only slightly (Boyden chamber) or not at all (agarose microdroplet) to the peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP). Equine mononuclear cell movement was increased by FMLP in both assay systems and these cells also respond...
Chirino-Trejo JM, Prescott JF.The antigens extracted from strains belonging to seven capsular serotypes of Rhodococcus equi, as well as from two wild strains isolated from pneumonic foals, were examined. Whole-cell antigens and soluble products present in broth culture supernatants were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroblotted onto nitrocellulose, and stained with serum from hyperimmunized rabbits or foals. Foal sera used included sera from pneumonic animals with known titer to equi factors; from animals bled monthly on a farm with enzootic pneumonia, and from animals bled mont...
Blue JT, Dinsmore RP, Anderson KL.Three horses developed severe, immune-mediated hemolytic anemia after treatment with penicillin. The horses had positive direct antiglobulin (Coombs) tests and high titers of IgG antibody that agglutinated penicillin-coated equine red cells. Two of the horses were tested for antibodies to autologous red cell antigens; autoantibodies were not present. Titers of antipenicillin antibody decreased after penicillin was discontinued but IgG antibody was detectable months after recovery. One of the horses was challenged with penicillin; antibody titer increased slightly, but anemia did not develop. A...
Smith HJ, Snowdon KE.Light Trichinella infections were established in three ponies given 1000, 5000 and 25000 T. spiralis spiralis infective larvae respectively by stomach tube. A predilection site of infection in all ponies was the tongue. Anti-Trichinella antibodies were detected in all ponies by the enzyme-linked immunosorbent assay using a T. spiralis spiralis excretory-secretory antigen. The ponies given 5000 and 25000 infective larvae reacted positively on days 26 and 24 postinfection, respectively, using a criterion of greater than or equal to 5 X mean optical density readings of preinfection sera as positi...
Edwards JF, Yedloutschnig RJ, Dardiri AH, Callis JJ.Virus isolation was attempted from 262 field samples of vesicular material collected during the outbreaks of vesicular exanthema of swine in the U.S.A. from 1952-54. Using primary swine kidney culture, viral cytopathogenic agents were isolated from 76.3% of the samples. However, an overall recovery rate of 82.1% was obtained after samples negative in tissue culture were inoculated intradermally in susceptible swine. All vesicular exanthema of swine virus isolates were identified as serotype B51 using complement fixation and serum neutralization tests. Two isolates did not react with antisera t...
Vandermyde CR, DiPietro JA, Todd KS, Lock TF.Fifteen pony foals were inoculated with 1,500 +/- 298.7 infective Parascaris equorum eggs. The foals were assigned to 3 treatment groups. Treatments included 10 mg of fenbendazole/kg given once on postinoculation day (PID) 11, 10 mg of fenbendazole/kg given daily on PID 11 to 15, and no treatment (controls). The foals were euthanatized on PID 25 and examined for P equorum larvae in the small intestine, lungs, and liver. Significantly (P less than 0.05) lower mean numbers of P equorum larvae were found in the small intestine of foals treated on PID 11 to 15 (1.4 [range, 0 to 6]) than in the sma...
Perdrizet JA, Scott DW.Cellulitis and subcutaneous abscess formation was diagnosed in a 3-month-old Thoroughbred filly. Clinical signs consisted of a large ulcerated plaque, with satellite pustules on the medial aspect of the right hock and subcutaneous abscesses in the right inguinal and mammary gland areas. Laboratory analysis revealed mature neutrophilia. Rhodococcus equi was isolated from the cellulitis and the subcutaneous abscess. Oral administration of erythromycin and rifampin for 35 days resulted in a clinical cure.
Blue J, Perdrizet J, Brown E.Acute myelomonocytic leukemia was diagnosed in a 2-year-old Standardbred mare that had hind limb edema and fever unresponsive to antibiotics. The mare had anemia, thrombocytopenia, and leukocytosis, with circulating myeloblasts and monocytoid cells. A bone marrow specimen was hypercellular, with myeloblasts and monocytoid cells. Peroxidase, chloroacetate esterase, and alpha naphthyl acetate esterase activities were detected in many bone marrow cells. Interstitial pulmonary densities were seen radiographically. The mare was euthanatized and necropsied. Infiltrates of leukemic cells were found m...
Shipton WA.The equine phycomycotic agent known commonly as Hyphomyces destruens or occasionally as Pythium gracile, is described as a new species Pythium destruens. Separation is on the basis of morphological features, temperature growth profiles, esterase/lipase activity, and carbohydrate utilization ability. P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens. P. destruens grew at 40 degrees C on corn meal agar and hydrolysed esters of lauric and oleic acids. These abilities were not displayed by P. diclinum, but this...
Mercer JG, Munn AE, Rees HH.Both free ecdysteroids and hydrolysable polar conjugated ecdysteroids were detected in protoscoleces of Echinococcus granulosus from the equine host, and in hydatid cyst fluid from the same source. Comparisons were made of hydatid cyst fluid from E. granulosus infections of three intermediate host species: horses, sheep and humans. Ecdysone and 20-hydroxyecdysone were identified in both protoscoleces and hydatid cyst fluids by high-performance liquid chromatography monitoring fractions by radioimmunoassay, and by capillary gas chromatography/mass spectrometry (selected ion monitoring). The fre...
Anderson RA, Gallaway WJ.The capillary tube precipitin test was used to determine the host utilization patterns of Culiseta inornata in southwestern Manitoba. Ruminant blood was identified in 83.3% and equine blood in 15.8% of 1,036 positively reacting blood-meals. Human, swine and avian blood accounted for 0.9% of these blood-meals and mixed blood-meals accounted for 1.5% of the total. Culiseta inornata preferentially fed on large mammals, and selection between cattle and horses reflected the relative abundance of these two hosts rather than a specific preference for either one.
Hall BG, Faunce W.The genes for utilization of cellobiose are normally cryptic in both laboratory strains and natural isolates of Escherichia coli. A survey of natural isolates of E. coli reveals that functional genes for cellobiose utilization, while rare, are present. The fraction of E. coli that utilized cellobiose ranged from less than 0.01% in human fecal samples to 7% in fecal samples obtained from horses. Samples obtained from sheep, cows, dogs, and pigs contained 0.1 to 0.5% cellobiose-positive E. coli. Neither the previously identified cel genes nor the bgl genes from E. coli K-12 were expressed during...
The Journal of heredityMay 1, 1987
Volume 78, Issue 3 171-177 doi: 10.1093/oxfordjournals.jhered.a110351
Leone NC, Shupe JL, Gardner EJ, Millar EA, Olson AE, Phillips EC.Hereditary multiple exostosis (HME), a bone tumor first described by Virchow, has been studied over a period of 15 years on a comparative basis. The horse, an excellent biomedical model for this physically deforming multiple bone tumor in man, has been utilized in this study. The etiology, hereditary pattern, potential for malignancy and other aspects of this strange affliction need additional clarification. This in-depth study of 261 individuals from 144 families was compared with that of 55 horses bearing the HME trait, selectively bred and studied over the same period. Important information...
May SA, Wyn-Jones G.Contrast radiography is a valuable technique in the investigation of infected foci in the horse. Its simplest form, a metal probe, will demonstrate the direction and, in the case of a short tract, the extent of the lesion. However, liquid contrast agents often give more information by following the course of long, tortuous sinus tracts, accurately delineating the boundaries of lesions and identifying the presence of foreign bodies.
Dart AJ, Hutchins DR, Begg AP.A 12-year-old Thoroughbred mare, with a history of anorexia, dramatic weight loss, fluctuating pyrexia and intermittent diarrhoea after an episode of colic, was presented for examination with depression, emaciation and ataxia. Thoracic and abdominal paracenteses yielded copious quantities of inflammatory exudate. Palpation per rectum revealed an enlarged spleen. The primary alterations in haematology included a severe leucocytosis with a left shift, and a hyperproteinaemia characterised by hypoalbuminaemia and hypergammaglobulinaemia. Post-mortem examination revealed a low grade pleurisy and p...
Rosendal S, Lumsden JH, Viel L, Physick-Sheard PW.Neutrophils were isolated from the peripheral blood of adult equids (group 1) and were purified on a density gradient of polyvinylpyrrolidone-coated silica gel. A bactericidal assay was developed, using an equine skin isolate of Staphylococcus epidermidis as target bacterium in medium containing pooled fresh equine serum for opsonization. Significant (P less than 0.05) killing was observed after 60 or 120 minutes' incubation. Reduction in bactericidal function of blood neutrophils was not found after incubation with a virulent strain of Mycoplasma felis for 30 or 60 minutes. Similarly, the fun...
Strzemienski PJ, Dyer RM, Sertich PL, Garcia MC, Kenney RM.The oestrous cycles of 20 mixed-breed mares were synchronized with daily injections of 10 mg oestradiol-17 beta and 150 mg progesterone given i.m. for 10 days. On the 10th day, 10-15 mg prostaglandin F-2 alpha was administered i.m. to induce oestrus. Neutrophils were isolated from jugular blood on the 2nd or 3rd day of oestrus, Days 5 and 7 after ovulation or during early pregnancy (Days 18-34 of pregnancy). Neutrophils were challenged with Staphylococcus aureus and their bactericidal activity examined after 30 and 120 min of incubation for a reduction of colony forming units. Bactericidal act...
DiPietro JA, Lock TF, Todd KS, Reuter VE.Twenty ponies less than 18 months of age and infected with Parascaris equorum were treated with either 0.2 mg of ivermectin/kg of body weight (n = 10) or a placebo (n = 10; controls). Five control and 5 ivermectin-treated ponies were euthanatized 14 and 35 days after treatment, respectively. At necropsy, the small intestinal contents, lungs, and liver were examined for larvae and/or adult P equorum. Significantly (P less than 0.02) higher mean total numbers of P equorum were found in the small intestinal contents of the controls on day 14 (51) and on day 35 (21) than in the ivermectin-treated ...
Strzemienski PJ, Sertich PL, Varner DD, Kenney RM.Stallion semen was diluted in a Hepes-supplemented buffer (CM) (10(6) spermatozoa/ml) and placed in the upper well of a Sykes-Moore chemotaxis chamber. Chambers were incubated in a humidified atmosphere (5% CO2 in air) at 37 degrees C for 1 and 2 h and spermatozoa were allowed to swim through filters with a mean pore size of 3,5 or 8 micron. Spermatozoa entered filters of all three pore sizes. Distance travelled was greater for each increase in pore size (P less than 0.01) but did not differ (P greater than 0.05) between 1 and 2h of incubation. Extended semen from stallions of different fertil...
Surma-Kurusiewicz K, Winiarczyk S, Adaszek Ł.The purpose of this study was to conduct a comparative analysis of the ORF5 gene fragment nucleotide sequences and the GP5 protein amino acid sequences formed on this matrix, for the equine arteritis virus (EAV) strains isolated from the semen of infected stallions from Eastern Poland. The study covered 41 stallions whose blood serum tested positive for antigens specific to the EAV. The presence of EAV genetic material was shown in material from 5 horses, in one of which permanent presence of viral RNA was detected over the entire 4-year study period (the material was sampled four times at yea...
Intemann S, Reckels B, Schubert DC, Wolf P, Kamphues J, Visscher C.Evidence has already been provided that feed-borne mold spores and endotoxins can trigger chronic, non-infectious respiratory disease if inhaled. Furthermore, deficiencies in feed microbiology are suspected to trigger gastrointestinal and liver disorders in horses, but the connection needs further clarification. Most of the previous studies regarding horse feed hygiene focused on forage, whereas research regarding hygienic quality of concentrates is scarce. In the present study, results of reports on hygienic quality of compound feed and cereals for horses were evaluated secondarily. Results i...
Müller AC, Büttner K, Röcken M.In postoperative monitoring of synovial structure infection due to limb wounds, early recognition of a recurrence of synovial infection is indispensable to prevent further damage to the affected synovial structure. This study evaluated the role of serum amyloid A (SAA) as a systemic biomarker in disease monitoring and correlated this tool with clinical variables. In this prospective cohort study, 55 horses with acute limb wounds were divided into two groups: those with (group 1, n = 26) or without (group 2, n = 29) a diagnosis of synovial structure penetration. SAA, lameness and body tempe...
Lopez MJ, Robinson SO, Cooley AJ, Prichard MA, McGinnis MR.An 18-year-old mare was evaluated for an oral mass that developed after extraction of a broken incisor. Results: An ulcerated, firm, darkly pigmented, approximately 5-cm-diameter spherical mass involved the gingiva lateral and dorsal to the right first to third maxillary incisors. Osteolysis of the roots of the first and second right maxillary incisors and periosteal proliferation of the adjacent premaxilla margins were apparent on radiographs. Histologic examination of the mass revealed multiple coalescing and ramifying foci of abscess formation, each containing a well-defined, discrete, blac...
Smith IM, Girard A, Corner AH, Mitchell D.Using two known positive equine viral rhinopneumonitis (EVR) sera, conjugates were prepared with fluorescein isothiocyanate and tested for specificity using EVR infected tissue culture cells. The conjugate was then applied to selected tissues from 32 aborted fetuses and foals submitted during a natural outbreak of EVR. Antigen was detected in various tissues by immunofluorescence in 20 cases (62.5%). In 24 cases bovine fetal kidney cell monolayers were inoculated with a pool of lung and liver and EVR virus was isolated from 15 (62.5%). Histological examination of various tissues from 29 cases ...
Mori S, Horita A, Ginnaga A, Miyatsu Y, Sawabe K, Matsumura T, Ato M, Yamamoto A, Shibayama K, Arai S, Yamagishi T, Takahashi M, Taki H, Hifumi T.This is the first report on large-scale experimental production of an equine antivenom against the redback spider (Latrodectus hasseltii) lived in Japan. We captured 10,000 redback spiders in Japan and prepared the toxoids of crude venom extract, mixed the toxoids with a mineral oil adjuvant, and immunized healthy horses repeatedly over a period of several weeks. Thereafter, we separated the horse plasma, purified the γ-globulin fraction, and stocked it as a purified antivenom concentrate. Consequently, we manufactured approximately 6,500 vials of a single-dose freeze-dried test lot from a po...
Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortázar C, Herskin M, Michel V, Miranda Chueca MÁ.... () was identified among the most relevant antimicrobial-resistant (AMR) bacteria in the EU for cattle and horses in previous scientific opinions. Thus, it has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on its eligibility to be listed, Annex IV for its categorisation according to disease prevention and control rules as in Article 9, and Article 8 for listing animal species related to the bacterium. The assessment has been performed following a methodology previously published. The outcome...
Mehdizadeh Gohari I, Boerlin P, Prescott JF.NetF-producing type A Clostridium perfringens, a pathotype of C. perfringens, causes necrotizing enteritis in neonatal foals and necrotizing and hemorrhagic enteritis in dogs. Recent core genome multilocus sequence typing study revealed that netF+ C. perfringens strains belong to two distinct clonal populations (clonal complexes I and II). There are no reports on susceptibility to antimicrobial drugs of isolates from this pathotype. The susceptibility to 13 different antimicrobial drugs of 49 netF+ strains recovered from foals or dogs with necrotizing enteritis in Canada, the United States, an...
Docherty DE, Samuel MD, Egstad KF, Griffin KM, Nolden CA, Karwal L, Ip HS.After the 2001 occurrence of West Nile virus (WNV) in Wisconsin (WI), we collected sera, during 2003-2006, from south-central WI mesopredators. We tested these sera to determine WNV antibody prevalence and geometric mean antibody titer (GMAT). Four-fold higher antibody prevalence and 2-fold higher GMAT in 2003-2004 indicated greater exposure of mesopredators to WNV during the apparent epizootic phase. The period 2005-2006 was likely the enzootic phase because WNV antibody prevalence fell to a level similar to other flaviviruses. Our results suggest that, in mesopredators, vector-borne transmis...
Dauphin G, Zientara S.West Nile virus, a flavivirus transmitted by mosquitoes, has been intensively studied since a few years because of epidemics/epizootics it has caused the last ten years, in particular around the Mediterranean basin and on the North-American continent. This virus mainly circulates in birds ; migrating bird species disseminate the virus while resident species could play a role in viral cycle amplification. A large number of mammal, amphibian and reptile species can also be infected. This virus can cause a lethal disease in humans and horses. For this reason, an active and/or passive surveillance...
Ma J, Zhang Z, Yao Q, Su C, Yin X, Wang X.Rev, an important accessory protein of equine infectious anaemia virus (EIAV), induces the nuclear export of incompletely spliced viral mRNAs. Rev is translated from the tat-rev mRNA through leaky scanning of the tat CUG. In this study, the function of the Kozak sequence at the beginning of the rev ORF was investigated. Deletion or attenuation of the Kozak sequence resulted in expression of an N-terminal 11 aa-truncated Rev in addition to WT Rev. Truncated Rev displayed weaker promotion of Gag expression and processing than WT Rev. Furthermore, EIAV rescued from an infectious molecular clon...
Kinoshita Y, Kakoi H, Ishige T, Yamanaka T, Niwa H, Uchida-Fujii E, Nukada T, Ueno T.Taylorella equigenitalis causes contagious equine metritis. Here we compared seven nucleic acid amplification tests for T. equigenitalis to select a rapid and reliable diagnostic method. The 95% detection limits of each assay varied greatly: real-time PCR had the lowest detection limit (0.77 fg/reaction); those of some of the conventional PCRs (cPCRs) were >100 fg/reaction. In experimentally infected samples, real-time PCR and semi-nested PCR showed the highest positive numbers (33 out of 42 samples), but two of the cPCRs detected only 2 and 7 positive results. Our results indicate that the us...
Skaggs JS, Reed Holyoak G, Montelongo M, Ayalew S, Confer AW.The immune responsiveness of mice (without prior natural exposure) and mares (with naturally acquired antibodies) was determined following vaccination with Actinobacillus equuli outer membrane proteins (OMPs) and/or recombinant A. equuli toxin (rAqx). Mice were vaccinated subcutaneously on days 0 and 21 with one of three doses (5, 25 or 50μg) of A. equuli OMPs, rAqx or both, together with Freund's incomplete adjuvant (FIA). Antibodies against formalin-killed whole bacterial cells (WBCs), OMPs and Aqx were determined on days 0, 21 and 42. Mares were vaccinated subcutaneously on days 0 and 21 w...
Black JB, Frampton AR.Equine herpesvirus type 1 (EHV-1) is a highly transmissible pathogen that leads to a variety of clinical disease outcomes in infected horses. A major sequela that can occur after an EHV-1 infection is a neurological disease termed equine herpesvirus myeloencephalopathy (EHM). Clinical manifestations of EHM include fever, ataxia, incontinence, and partial to full paralysis, which may ultimately lead to the euthanization of the infected horse. To develop an effective treatment strategy for EHM, it is critical that the specific virus-host interactions that lead to EHM be investigated so that safe...
Montelaro RC, West M, Ivey M.Representative glycoproteins including fetuin, protein A, ovalbumin, alpha 1 acid glycoprotein, and the major glycoprotein of equine infectious anemia virus were labelled with 125I by the chloramine-T or Bolton-Hunter procedure and their binding to immobilized Con A or lentil lectin compared to untreated samples of each glycoprotein. Glycoprotein modification was no greater than one substituted residue per protein molecule. Yet the radioiodinated glycoproteins typically displayed only 0-50% of the lectin binding observed with untreated samples. These results indicate that lectin glycoprotein b...
Inzana TJ, Iritani B.A group C latex agglutination reagent, included as the negative control in the PathoDx Strep A latex agglutination test (Diagnostic Products Corp., Los Angeles, Calif), was compared with culture for rapid detection of group C streptococci (Streptococcus equi, S. equisimilis, S. zooepidemicus, and S. dysgalactiae) from swabs of veterinary specimens. The overall sensitivity of the latex test was 78%, and specificity was 97.6%. Only 25% of S. dysgalactiae isolates were detected, thereby accounting for the relatively low sensitivity. Ninety-three percent of the group C streptococci other than S. d...
Perryman LE, Magnuson NS.Significant contributions to understanding the role of lymphocyte subpopulations in the immune response and to the characterization of immunodeficiencies in children have been achieved through study of animal models of immunodeficiency. Additional contributions can be made in two important areas. One is through identification of relevant, naturally-occurring models of adenosine deaminase deficiency and purine nucleoside phosphorylase deficiency. The second, and potentially more important contribution, would be the identification of the metabolic basis for existing immune deficiencies. The nece...
Ahn B, Zhang Y, Osterrieder N, O'Callaghan DJ.The 150 kbp genome of equine herpesvirus-1 (EHV-1) is composed of a unique long (UL) region and a unique short (Us) segment, which is flanked by identical internal and terminal repeat (IR and TR) sequences of 12.7 kbp. We constructed an EHV-1 lacking the entire IR (vL11ΔIR) and showed that the IR is dispensable for EHV-1 replication but that the vL11ΔIR exhibits a smaller plaque size and delayed growth kinetics. Western blot analyses of cells infected with vL11ΔIR showed that the synthesis of viral proteins encoded by the immediate-early, early, and late genes was reduced at immediate-early...
Byrns G, Crump AL, Lalonde G, Bernoco D, Antczak DF.The ELY-1 locus controls the expression of a polymorphic cell surface antigen of equine lymphocytes which was detected using antibodies generated by alloimmunization with peripheral blood lymphocytes. The ELY-1 antigens were not detected on erythrocytes or platelets by absorption experiments. The two alleles, which have been designated ELY-1.1 and ELY-1.2, are expressed codominantly and appear to constitute a closed system at the population level. In family studies, the ELY-1 antigens segregated as products of an autosomal locus not linked to the major histocompatibility complex (MHC) of the h...
Tantawichien T, Benjavongkulchai M, Wilde H, Jaijaroensup W, Siakasem A, Chareonwai S, Yountong C, Sitprija V.The high cost of postexposure prophylaxis for rabies is one reason that treatment is inadequate in developing countries. This problem has kindled interest in the use of equine rabies immune globulin, which is a less expensive, yet effective, substitute for human rabies immune globulin. Fatal anaphylaxis is a feared complication of the administration of heterologous serum; therefore, authoritative sources recommend prior skin testing. However, recommendations for methods of administering such a skin test and for its interpretation vary greatly. We embarked on a long-term study to develop guidel...
Rojas G, Vargas M, Robles A, Gutiérrez JM.Twenty batches of polyvalent antivenom produced at the Instituto Clodomiro Picado were analyzed for turbidity, both before and after freezing-thawing and lyophilization. Eight batches became turbid upon freezing-thawing, and this change correlated with high levels of cholesterol, triglycerides and lipoproteins, especially beta-lipoprotein. Since normal horse serum does not become turbid after freezing-thawing, despite the fact that it has high lipoprotein levels, the possibility was raised that phenol, used as a preservative during serum fractionation, might affect lipoproteins, inducing the a...
Allen GP, Cohen JC, Randall CC, O'Callaghan DJ.The replication of equine herpesvirus type 1 (EHV-1) and type 3 (EHV-3) was unimpeded in three different cell types-equine epithelial cells, equine fibroblasts, and mouse fibroblasts-which had been blocked in their capacity to synthesize host DNA by 2.5 mM hydroxyurea (HU) or 2 mM thymidine (TdR). The rate of DNA synthesis in uninfected or equine herpesvirus-infected cells in the presence of HU or TdR was measured by pulse-labeling cell samples with a labeled DNA precursor at different times after infection. DNA synthesis in uninfected cultures was completely inhibited by both compounds. Howev...
Balke E, Weiss R, Seipp A.A total of 110 strains of beta-hemolytic streptococci, belonging to serogroup C (Lancefield), isolated from horses (71 S. zooepidemicus, 27 S. equisimilis and 12 S. equi) as well as 5 reference strains were tested for their ability to produce hyaluronidase. The determinations were carried out in a culture test on agarose gel and in a liquid test system (turbidity test according to DiFerrante). The results of both methods used showed that the three Streptococcus species could be differentiated by the relative quantitative determination of hyaluronidase activity. S. equisimilis strains produce 5...
Blue HB, Blue MG, Kenney RM, Merritt TL.Forty uterine fluid samples were obtained from 4 mares classified as resistant to uterine bacterial infection. The uterus of each mare was flushed with 50 ml of saline solution during estrus and diestrus of successive estrous cycles. Bacteria or fungi were isolated from 4 samples, and 7 additional samples were obtained from a mare with active intrauterine infection. Fluid volumes obtained during estrus (means = 40.3 +/- 11 ml) tended to be greater than those recovered during diestrus (means = 36.8 +/- 7.9 ml), but the difference was not significant. Concentrations and yields of protein in reco...
Uzcanga GL, Bubis J.Two horses were infected with distinct non-tsetse transmitted Venezuelan stocks, namely TeAp-N/D1 and TeAp-El Frio01 . Preceding reports have revealed that a 64-kDa antigenic glycopolypeptide (p64), which is the soluble form of the predominant variant surface glycoprotein from TeAp-N/D1 , can be used as a good antigen for immunodiagnosis of animal trypanosomosis. Here, the course of the experimental acute infection in both horses was monitored by evaluating total anti-p64 IgG and particular anti-p64 γ-specific IgG and μ-specific IgM isotypes in sera using indirect enzyme-linked immunoso...
Traversa D.The recognition that the health and welfare of some humans are improved through contact and relationships with animals is now established. Two commonly recognized assistance animals are dogs and horses. Both provide therapeutic benefits to humans with some physical and mental illnesses and both assist people with disabilities. Moreover, the public and scientific attention to the health and conservation of many animal breeds is also increasing worldwide. In the past few years, two potentially life-threatening nematode infections that can induce tumours or tumour-like masses in canids and equids...
Suzuki Y, Takai S, Kubota H, Hasegawa N, Ito S, Yabuuchi Y, Sasaki Y, van Duijkeren E, Kakuda T.Rhodococcus equiis the causative agent of pyogenic pneumonia in foals, and a virulence-associated protein A (VapA) encoded on the pVAPA virulence plasmid is important for its pathogenicity. In this study, we analyzed the virulence of R. equi strain U19, originally isolated in the Netherlands in 1997 and the genetic characteristics of the pVAPA_U19 plasmid. U19 expressed VapA that was regulated by temperature and pH and underwent significant intracellular proliferation in macrophages. The restriction fragment length polymorphism of pVAPA_U19 digested with EcoRI was similar to that of pREAT701 (...
Amory H, Cesarini C, De Maré L, Loublier C, Moula N, Detilleux J, Saulmont M, Garigliany MM, Lecoq L.The objective of this retrospective study was to evaluate the clinical significance of fecal quantitative real-time polymerase chain reaction (qPCR) results when taking the cycle threshold values (Ct) into account. The study included 120 qPCR-positive fecal samples obtained from 88 hospitalized horses over a 2-year period. The mean Ct of the qPCR test was evaluated in regard to (1) clinical outcome and (2) systemic inflammatory response syndrome (SIRS) status (no SIRS, moderate SIRS, or severe SIRS) of the sampled horses. An ROC analysis was performed to establish the optimal cut-off Ct valu...
Wilkins PA.Rapid evaluation and intervention is a requirement and a characteristic of patient management in neonatal intensive care units, and this applies for equine neonates also. Appropriate interventions are based on solid knowledge of age, maturity, and species-specific differences in reference ranges. Point-of-care (POC) testing devices speedup decision making regarding treatments and interventions. However, there are potential limitations of these devices when applied to age groups and species beyond those they were specifically developed for. This article discusses the age-specific differences in...
