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.
Dean PW, Robertson JT.A urachal remnant, causing pollakiuria and dysuria, was diagnosed by rectal palpation of a urinary bladder adhesion and endoscopic visualization of a urinary bladder diverticulum. Surgical excision of the remnant resulted in relief of abnormal micturition, but the filly was euthanatized 9 months after surgery because of a chronic ventral midline incisional infection. Pollakiuria and dysuria associated with urachal abscessation occur most commonly in calves. This report documents the syndrome in a horse.
Songer JG, Beckenbach K, Marshall MM, Olson GB, Kelley L.Isolates (n = 94) of Corynebacterium pseudotuberculosis were obtained from sheep, goats, horses, and cattle from various parts of the world. The isolates were characterized biochemically and by restriction endonuclease analysis of DNA. We found near homogeneity in the ability of isolates to ferment carbohydrates and to produce urease. All isolates produced phospholipase D and catalase. The ability of isolates from horses to reduce nitrate, the inability of isolates from sheep and goats to do so, and the correlation of this characteristic with results of restriction endonuclease analyses confir...
Mendoza L, Alfaro AA, Villalobos J.A 5-year-old, female saddle horse developed a tumoral mass anterolaterally on the metacarpal region of its right front leg. Histopathological study showed hyaline, aseptate, broad hyphae in the sequestered coral-like necrotic masses. Radiographs revealed an extensive osteomyelitis with disorganized bone proliferation of the metacarpal bones, as well as exostosis of the distal radius and the proximal and distal row of carpal bones. The etiologic agent was detected histologically, isolated in culture and identified as Pythium insidiosum. Serological tests were positive. Immunotherapy was applied...
Murray MJ, Ball MM, Parker GA.A 3-month-old foal with a history of persistent fever and leukocytosis was found to have pneumonia, ulceration of the squamous portion of the stomach, and dilatation of the distal portion of the esophagus. The foal was euthanatized and necropsied. The distal portion of the esophagus was severely dilated, and there was severe ulceration and mural thickening of the stomach at the cardia. Because of the severe gastric ulceration and mural thickening, the gastroesophageal junction was fixed in an open position, permitting gastroesophageal reflux. The megaesophagus and pneumonia were considered to ...
Bridges CG, Ledger N, Edington N.Ponies, without evidence of previous exposure to Equine herpes virus-1 (EHV-1), were experimentally infected with EHV-1 subtype 2 and investigated for lymphocyte transformation to virus-infected cell polypeptides, as shown by separation with gel electrophoresis. Animals made significant responses to Western blot fractions that corresponded to molecular weights of approximately 30,000, 40,000-45,000, 60,000-65,000, 80,000-95,000 and 100,000-140,000 MW. These molecular weight ranges correlated with the positions of major EHV-1 subtype 2 glycoproteins that were found at migration distances approx...
Palmer JE, Whitlock RH, Benson CE.Equine ehrlichial colitis was experimentally induced in 18 ponies, using Ehrlichia risticii-infected blood. Four ponies (group 1) were treated with oxytetracycline (6.6 mg/kg of body weight, IV, q 12 h), beginning 14 hours before inoculation and continuing for 5 days after inoculation. Four additional ponies (group 2) were treated similarly for 10 days after inoculation. The remaining 10 ponies were used as nontreated, infected controls. Clinical disease was delayed in 3 group-1 ponies and in 4 group-2 ponies. Protective immunity developed in the remaining pony that did not develop clinical di...
Belknap J, Arden W, Yamini B.A 2-month-old Standard-bred colt with signs of abdominal pain and large scrotum was found to have septic periorchitis involving the right testis. Surgical exploration of the abdomen and scrotum was performed; the colt was then castrated. Actinobacillus equuli was isolated from specimens obtained at surgery. The colt was treated with broad-spectrum antibiotics and flunixin meglumine after surgery, and fully recovered. The clinical signs of periorchitis in the colt were similar to an inguinal/scrotal hernia.
Divers TJ, Byars TD, Spirito M.Bilateral ureteral defects were diagnosed as the cause of depression and azotemia in an 8-day-old Thoroughbred filly. The azotemia resulted from accumulation of urine in the retroperitoneal area. A ventral midline laparotomy was performed, and defects found in both the left and right ureter were repaired. Uroperitoneum and abdominal distention, presumably from urine leakage at the left ureteral surgery site, were detected on the fourth postoperative day and necessitated abdominal drainage. Thirty-six hours later, the leakage stopped spontaneously, and the foal recovered normally. This report s...
Plenderleith RW.In large animal practice, clinical cases involving deep-seated infections affecting bones, joints, meninges and the larynx are particularly difficult to treat. The antibiotic lincomycin has the ability to penetrate tissue of poor vascularity and is also effective in the presence of pus. Eleven cattle, six sheep and three horses were treated with the drug at various doses and in 75 per cent of the cases there was a positive response.
Boyd EH, Allen WE.Plasma concentrations of neomycin were measured after intrauterine infusion of 3.3 mg/kg neomycin sulphate. Mares infected two hours previously with an intra-uterine infusion of beta-haemolytic streptococci absorbed approximately 12 per cent of the neomycin in both the oestrous and the luteal phases of the cycle. Normal mares in oestrus absorbed 6 per cent of the neomycin infused and luteal mares absorbed 56 per cent. In infected mares the peak plasma concentrations occurred two hours after neomycin infusion, earlier than in healthy mares. Cervical flushings after neomycin infusion in infected...
Lyons ET, Drudge JH, Tolliver SC.During 1986, fecal specimens were collected 1 or more times from each of 164 horse foals (158 Thoroughbred and 6 mixed light horse type), ranging in age from 0 to 252 days, on 13 farms in central Kentucky. To detect natural infection with Eimeria leuckarti, feces were examined for oocysts. Oocysts were found in 67 (41%) of the foals on 11 (85%) of the farms. The earliest age at which oocysts were first detected was 15 days (1 foal); the latest age was 123 days (1 foal). The mean age for the first appearance of oocysts in the feces of the 67 foals positive for E leuckarti was approximately 70 d...
Cabañes FJ, Abarca L, Bragulat MR, Bruguera T.A phaeohyphomycotic infection caused by Alternaria alternata is reported in a 5-month-old Spanish mare. The diagnosis was made by direct microscopic examination and by repeated isolation of the fungus in culture. This is the first documented case to be reported in Spain.
Principato M.Listed and described herein are the main macroscopic lesions produced along the whole digestive tract of free-ranging horses by larvae of the five Gasterophilus spp., occurring in Umbria, a region of central Italy: Gasterophilus intestinalis, Gasterophilus nasalis, Gasterophilus pecorum, Gasterophilus inermis, Gasterophilus haemorrhoidalis. Lesions are classified on the basis of their sizes and shapes and the host's anatomic sites infested, and they are examined in relation to the developmental stages of larvae causing them. The examination of the lesions shows that it is very difficult to dif...
Brewer BD, Koterba AM.A sepsis scoring system was developed and tested prospectively in a blind study of 190 neonatal foals admitted to the University of Florida Veterinary Medical Teaching Hospital's neonatal intensive care unit. The system used 14 readily available historical, clinical or laboratory variables and weighted each item to arrive at a sepsis score. The score was found to have a sensitivity of 93 per cent, a specificity of 86 per cent, positive accuracy rate of 89 per cent and negative accuracy rate of 92 per cent. The sepsis score was far more sensitive and specific for infection, even in very early c...
Bermudez V, Miller RB, Johnson W, Rosendal S, Ruhnke L.The growth of Mycoplasma equigenitalium and Mycoplasma subdolum from specimens collected from the clitoral fossa of each of four Standardbred mares was not diminished by freezing of the specimens in liquid nitrogen (-196 degrees C) for up to 30 days when compared to samples cultured immediately.
Burgess EC.Blood samples from Wisconsin horses and cows suspected of having clinical disease due to Borrelia burgdorferi infection were submitted by veterinary practitioners. All serum, milk, colostrum, and synovial samples were tested for B. burgdorferi antibodies by immunofluorescence. Whole blood, milk, colostrum, and synovial fluid samples were cultured for B. burgdorferi. Records were kept on the clinical signs of antibody-positive animals, date of sample, and location of the animal by county. Of the samples tested for antibodies 282/430 cow sera, 118/190 horse sera, 5/10 cow synovial fluids, 3/6 ho...
Thein P, Brown K.Infections with EHV1 can lead to manifestation at the CNS of horses followed by encephalomyelitis and "equine stroke". Horse experiments could confirm the clinical picture and gave links to the potential pathogenesis of the disease. We also have been in the position to isolate and characterize an EHV4 virus out of the brain of a horse with CNS disorders. The two viruses carry different biological properties which obviously dominate the pathogenesis. These properties as well as experimental and field cases are described and different diagnostic tests are discussed.
Browning GF, Ficorilli N, Studdert MJ.Two previously unknown and distinct herpesviruses were isolated from donkeys. One, with the characteristics of a betaherpesvirus, was isolated from the leukocytes of an apparently healthy donkey, while the second, an alphaherpesvirus, was recovered from the nasal cavity of donkeys given high doses of corticosteroids, and caused rhinitis in two seronegative weanling donkeys when they were intranasally infected. Few, if any, restriction endonuclease fragments were shared by the donkey betaherpesvirus, equine herpesvirus 2 (EHV 2) or EHV 5, a second distinctly different equine betaherpesvirus, no...
Perryman LE, Wyatt CR, Magnuson NS, Mason PH.Monoclonal antibodies specific for equine T lymphocyte subpopulations were produced and procedures for the continuous culture of equine lymphocytes were developed. These reagents and procedures were used to analyse the appearance, maturation and functions of T lymphocytes in normal horses and in T lymphocyte deficient horses with severe combined immunodeficiency (SCID). T lymphocytes appeared as early as the 75th day of fetal development and were normally distributed prior to birth of normal foals. Analysis of thymic T lymphocyte differentiation in SCID foals revealed the presence of both prot...
Adams R, Koterba AM, Cudd TC, Baker WA.The medical records of 18 neonatal foals, in which exploratory celiotomies were performed for suspected urinary tract lesions, were reviewed. Despite clinical signs and laboratory values indicative of disruption of the urinary tract, three foals did not have a site of urinary tract leakage at surgery. Eight foals had ruptured bladders and seven foals had urachal lesions. Ultrasonography was used as a pre-operative diagnostic procedure in eight foals to evaluate the presence of free peritoneal fluid and urinary tract integrity. Nine foals were alive six months after discharge. Seven of the nine...
Bosler EM, Cohen DP, Schulze TL, Olsen C, Bernard W, Lissman B.By using paired sera the IgM and IgG host responses were analyzed in dogs with ELISA and Western blot techniques. Antibodies in clinical seropositive dogs bound to 4-25 IgM and up to 40 or more IgG antigenic determinants. Early IgM response to the 41-kDa flagellin persisted for at least 9 months and involved as many as seven other peptides. IgG response expanded later in the disease and involved more immunogens than are currently recognized in late human disease. A percentage of asymptomatic dogs that later developed clinical symptoms were seropositive. Immunoblot studies suggested that B. bur...
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...
Kuttler KL, Goff WL, Gipson CA, Blackburn BO.Both the complement-fixation test (CFT) and the indirect fluorescent antibody test (IFAT) were conducted on weekly serum samples from nine Arab geldings for 28 days before and 256 days after their exposure to Babesia equi of European origin. On an average the IFAT became positive 8 days before the CFT and showed higher relative serum titer increases. Both test procedures successfully detected infection and neither showed an appreciable drop in titer during this time frame, with the exception of the CFT, which showed a transient drop immediately following treatment with imidocarb. A test conduc...
Cohen D, Bosler EM, Bernard W, Meirs D, Eisner R, Schulze TL.A serologic survey of horses in the New Jersey-Pennsylvania area demonstrated that about 10% (6.2-14.2%) have significant levels of serum antibody to Borrelia burgdorferi. However, in a highly endemic area of central New Jersey, up to 60% of the mares and yearlings samples on one farm were seropositive. In 1983, sera from this same farm exhibited only 12% positives in mares and 35% positives in yearlings. Longitudinal studies of paired sera obtained from individual yearlings over a 6-month period in 1985 showed that 34% of them declined during the period. A new clinical syndrome associated wit...
De Almeida JC, Augusto Mde M, Da Silva TG, De Toledo PS, De Souza DF, Antunes J, Molento MB.The objective of this work was to determine the quantitative prevalence of Anoplocephala sp. in thoroughbred horses raised in São José dos Pinhais, PR using the modified centrifugal-flotation technique. Repeatability values for the eggs per gram (EPG) were evaluated at 28-day intervals. The coproparasitological tests were made in 28 one-year old animals, 25 two-year old animals and 28 mares during the 2007 period of January 31st and June 15th. In the comparison of EPG, all mares presented low values than the foals (P = 0.04). The prevalence results indicated 50, 18 and 40% Anoplocephala sp. ...
Cian F, Whiteoak S, Stewart J.A 12-year-old British Warmblood mare was examined by the referring veterinarian for evaluation of a cutaneous lesion on the dorsal thorax to the right of the midline. Cytologic examination of fine-needle aspirates from the mass was supportive of a giant cell tumor of soft parts (GCTSP). Laser surgical excision and postoperative methyl aminolevulinate (MAL) photodynamic therapy (PDT) were performed. Histologic examination of the mass confirmed the cytologic diagnosis. At 8 months from surgery, no evidence of recurrence has been observed. Giant cell tumors of soft parts are rare cutaneous neopla...
Waelchli RO, Corboz L, Doebeli M.To investigate the vulvovestibular contamination of endometrial culture swabs in the mare, a liquid culture of a streptomycin-resistant strain of Escherichia coli was applied to the vulvovestibular area of mares and used as a marker of contamination of endometrial culture swabs. Prior to taking endometrial swabs, the perineal area was washed with soap, rinsed with water, and dried. Endometrial culture swabs were taken from mares that were in anestrus or diestrus and from mares that were in estrus. When a manual transvaginal swabbing technique was used, 22 of 24 endometrial swab specimens from ...
Dill SG, Simoncini DC, Bolton GR, Rendano VT, Crissman JW, King JM, Tennant BC.During a period of 18 months, between July 1978 and January 1980, 4 adult horses were referred to the New York State College of Veterinary Medicine with evidence of congestive heart failure. Characteristic clinical abnormalities included marked muffling of heart sounds, tachycardia, jugular vein distention, and peripheral edema. Treatment with antibiotics, diuretics, and anti-inflammatory drugs was unsuccessful, and all four died or were euthanatized and necropsied. At necropsy, there was marked distention of the pericardial sac with fluid, and thick layers of fibrin were deposited uniformly o...
Drummer HE, Reynolds A, Studdert MJ, MacPherson CM, Crabb BS.Sera from 33 Australian thoroughbred mares were tested during an outbreak of equine herpesvirus 1 (EHV1) abortion with an enzyme-linked immunosorbant assay (ELISA) for the presence of EHV1-specific antibodies. The ELISA used a recombinant EHV1 antigen derived from glycoprotein G (gG) and distinguished antibodies to EHV1 from those of the antigenically related and widespread herpesvirus EHV4. Sera were obtained from most of the mares on three occasions, three, 13 and 67 days after the first abortion. Mares which were negative in the ELISA were kept separate from mares which were positive. A sec...
Cymerys J, Słońska A, Chodkowski M, Golke A, Krzyżowska M, Bańbura MW.Equid herpesvirus 1 (EHV-1) causes respiratory disease, abortion and neurological disorders in horses. Similarly, to other alphaherpesviruses, EHV-1 is neurotropic and establishes latency in the neurons of its natural host. Despite the fact that many studies have been devoted to the pathogenesis of various clinical forms of EHV-1 infection, mechanisms of the neuronal damage are still not fully understood. The aim of this study was to define the phosphorylation status of tau protein in neuronal cell culture infected with EHV-1. Phosphorylation of tau was tested at tau-ser199/ser202, tau-ser404,...
Stefanetti V, Pascucci L, Wilsher S, Cappelli K, Capomaccio S, Reale L, Passamonti F, Coletti M, Crociati M, Monaci M, Marenzoni ML.Endogenous retroviruses (ERVs) are proviral phases of exogenous retroviruses, which have coevolved with vertebrate genomes for millions of years. The conservation of ERV genes throughout evolution suggests their beneficial effects on their hosts' survival. An example of such positive selection is demonstrated by the syncytin gene, which encodes a protein with affinity for various mammalian placentas that is involved in the formation of syncytiotrophoblasts. Although the horse has an epitheliochorial placenta, in which the fetal trophoblasts are simply apposed to the intact uterine epithelium, ...
Jager MC, Tomlinson JE, Henry CE, Fahey MJ, Van de Walle GR.Theiler's disease, a.k.a. equine serum hepatitis, is a devastating, highly fatal disease of horses. Equine parvovirus-hepatitis (EqPV-H) has been identified as the likely cause of this disease. While the incidence of Theiler's disease is low, the prevalence of EqPV-H DNA in horses is high, with up to 37% in some regions, suggesting that subclinical or persistent infection is common. To determine the prevalence and pathogenicity of EqPV-H infection at New York racetracks, DNA was extracted from archived formalin-fixed, paraffin-embedded liver tissues from racehorses submitted for necropsy to th...
Losinno SJ, Aguilar J, Carbonetti L, Ferniot E, San Esteban F, Flores Suares CM.Strategies for parasite control have undergone major changes in recent years, especially in Europe and the United States, replacing traditional approaches by schemes based on surveillance and selective therapy. A first step in helminth control planning is to understand and demonstrate how horse owners or trainers currently control nematodes. The aim of this study was to collect information, through a survey, about important aspects of routine anthelmintic strategies in sport horses in Argentina and other regional countries. A total of 100 surveys were sent. Sixty nine were responded, 53% of th...
Gharaibeh MH, Abutarbush SM, Mustafa FG, Lafi SQ, Halaiqa MS.Antimicrobial resistance is a growing global problem that will need a multinational collaborative effort to overcome this serious challenge. The aim of the study is to investigate the potential risk factors associated with the prevalence and distribution of antimicrobial-resistance genes (ARGs) of Escherichia coli isolates obtained from equine fecal samples. One hundred and eighteen horses from different geographical locations and management systems were enrolled in the study and a questionnaire containing information about each individual horse was designed and filled. The enrolled horses bel...
Sternberg S, Johannisson A, Magnusson U, Jensen-Waern M.After exposure of equine granulocytes from both foals and adult horses to culture supernatants from clinical isolates of Actinobacillus equuli, phagocytic capacity and respiratory burst was examined by flow-cytometry and a chemiluminescence assay, respectively. One haemolytic isolate of an equine Actinobacillus was also included in the study. An average decrease of 22% in total number of granulocytes, in the flow cytometric assay (P < 0.01), and an average decrease of 26% in light emission, in the chemiluminescence assay (P < 0.001), was seen after exposure to bacterial culture supernata...
Foster AP, Cunningham FM.Equine eosinophils and neutrophils are believed to play an important part in the protection of horses against parasitic and bacterial invasion. Eosinophils may also play a key role in the pathogenesis of equine inflammatory conditions such as the allergic skin disease, insect hypersensitivity. The factors which stimulate the respiratory burst of equine eosinophils and neutrophils are poorly understood. The first aim of the present study was to determine the effects of the phorbol ester, phorbol myristate acetate (PMA), which is believed to activate intracellular protein kinase C, and opsonised...
Kettner NU, Parker JE, Watrous BJ.A 2-week-old Morgan filly examined because of lameness of 5 days' duration was found, on the basis of clinical and radiographic findings, to have septic physitis of the distal end of the radius. The foal was treated by means of intraosseous regional perfusion with penicillin and amikacin and systemic administration of antimicrobials. Intraosseous regional perfusion was performed 3 times. The foal was anesthetized for the first episode of intraosseous regional perfusion, but was only sedated for the subsequent 2 episodes. Antimicrobials were administered systemically for 22 days. Foals with sep...
Lorenzo FDR.Non-unions at forearms are usually challenging and difficult to treat. If additionally, an infection is present, reconstructive surgery should be planned only after full debridement, antibiotic treatment, and confirmation, based on clinical observation and laboratory tests that the infection has subsided. Bone grafting may be required for reconstruction. The use of autogenous bone calls for a second surgical site with an increased risk of morbidity. Using bone substitutes may reduce the need for autogenous bone. Stimulating factors, such as bone marrow concentrate (BMC) and demineralized bone ...
Dwyer RM.Disinfection of equine premises provides a challenge to farm managers, in view of the variety of surfaces which may be contaminated and the wide variety of horse pathogens. Of the commonly occurring infectious diseases for which disinfection and disease control are especially important, rotavirus diarrhoea, salmonellosis and strangles are the most difficult to control. Phenolic disinfectants have been scientifically demonstrated to be effective in the presence of organic matter and are also virucidal. When used after thorough cleaning and rinsing of stall surfaces, phenolics have proved effect...
Salco R, Bowers J, Hernandez V, Barnum S, Pusterla N.This study aimed to determine if the administration of a modified live equine influenza virus vaccine (FluAvert) to foals would positively impact their health and reduce colonization of their upper airways with equine herpesviruses (EHV) during the weaning period. A single dose of FluAvert was given to 20 healthy foals 7 days prior to being weaned; 20 healthy foals served as unvaccinated controls. Nasal secretions and blood were collected before vaccination, the day of weaning, and weekly thereafter for 3 weeks. Nasal secretions were tested by quantitative polymerase chain reaction (qPCR) for ...
Andersen S, Fogh J.During a 5 months' period from January to May 1981 faecal samples of 176 donkeys from 59 herds all over the country were examined at the Institute of internal medicine, The Royal Veterinary and Agricultural University, Copenhagen. In addition, the investigation also included 106 horses from 30 of the donkey herds and 34 horses hospitalized with symptoms of dyspnoea and chronic coughing. In all, 87.5% of the donkeys were shown to excrete D. arnfieldi larvae, often in very high numbers, and the larval excretion was the only symptom of lungworm infection. There was no significant correlation betw...
French DA, Fretz PB.A retrospective study was conducted on 35 equine patients with lower leg wounds that were managed utilizing skin graft procedures. Two pinch graft, five punch graft, seven tunnel graft, eight split-thickness mesh graft and thirteen full-thickness mesh expansion graft procedures were performed in the initial treatment. The average wound size was 188 cm(2). Twentyfour cases had pregrafting complications: 10 wounds developed sequestra; three wounds were grossly contaminated and infected; and 11 cases developed granulation tissue complications prior to grafting. Graft failure following the initial...
Rossano MG, Schott HC, Kaneene JB, Murphy AJ, Kruttlin EA, Hines MT, Sellon DC, Patterson JS, Elsheikha HM, Dubey JP, Mansfield LS.To determine whether daily administration of pyrantel tartrate can prevent infection in horses experimentally challenged with Sarcocystis neurona. Methods: 24 mixed-breed specific-pathogen-free weanling horses, 10 adult horses, 1 opossum, and 6 mice. Methods: Sarcocystis neurona-naïve weanling horses were randomly allocated to 2 groups. Group A received pyrantel tartrate at the labeled dose, and group B received a nonmedicated pellet. Both groups were orally inoculated with 100 sporocysts/d for 28 days, 500 sporocysts/d for 28 days, and 1000 sporocysts/d for 56 days. Blood samples were collec...
Zhang K, Ju Z, Zhang Y, Wang C, Mubalake S, Hu D, Zhang D, Li K, Chu H.The genus Gasterophilus (Diptera, Gastrophilidae) is an obligate parasite of the equine family that causes widespread myiasis in desert steppe. Based on four common naturally excreted Gasterophilus larvae collected systematically in the Karamaili Ungulate Nature Reserve from March to September 2021, this paper studies the population dynamics and ontogenetic laws of horse flies, and discuss the coexistence pattern and population dynamics prediction of horse flies. The results showed that the Gasterophilus larvae had obvious concentrated development period, and the time of population peaks was d...
Hashikura S, Higuchi T, Taharaguchi S, Orita Y, Nanao Y, Takai S.The reliability of preparing bacteriological cultures from nasotracheal aspirates of foals routinely in order to diagnose R. equi pneumonia in foals was studied by isolating Rhodococcus equi from specimens obtained from 96 foals by nasotracheal aspiration with a silicon catheter. Results were compared with specimens obtained from 21 foals by transtracheal aspiration (percutaneous tracheal puncture). These 117 foals showed clinical signs of respiratory tract infection at sampling. R. equi was isolated from 14 of 21 (66.7%) specimens by transtracheal aspiration and from 59 of 96 (61.4%) specimen...
Morgan SJ, Storts RW, Stromberg PC, Sowa BA, Lay JC.Factors involved in the proliferation of equine vascular smooth muscle cells were studied in vitro. The most prominent proliferative responses in cultured vascular smooth muscle cells were induced by Strongylus vulgaris larval antigen extract (LAE) and platelet-derived factors. Less significant proliferative responses were obtained with conditioned media from S. vulgaris LAE stimulated and from unstimulated equine mononuclear leukocytes. Additionally, vascular smooth muscle cells exposed to S. vulgaris LAE developed numerous perinuclear vacuoles and were more spindle-shaped than control or smo...
Honnas CM, Schumacher J, Kuesis BS.A 6-month-old 300-kg Quarter Horse filly was treated for septic arthritis of the distal interphalangeal joint and septic navicular bursitis that developed as a result of a deep puncture to the foot. Initial treatment consisted of establishing ventral drainage for the navicular bursa, lavage of the distal interphalangeal joint, and administration of broad-spectrum antimicrobial drugs and non-steroidal anti-inflammatory drugs. Because of continuing sepsis in the distal interphalangeal joint, subsequent treatment included packing the defect in the bottom of the foot with cancellous bone in an att...
Crabill MR, Cohen ND, Martin LJ, Simpson RB, Burney N.Equine synovial fluid aliquots were inoculated with Salmonella enteritidis, Escherichia coli, Actinobacillus equuli, Staphylococcus aureus, and Streptococcus zooepidemicus to obtain approximate concentrations of 1000, 100, 10, and 1 colony forming U/mL. Synovial fluid aliquots were also inoculated with an unquantitated inoculum of Bacteroides fragilis and Clostridium perfringens. Inoculated synovial fluid was incubated in trypticase-soy broth or Columbia broth for approximately 12 hours. Then aliquots were removed for DNA extraction and polymerase chain reaction (PCR) analysis for detection of...
Rossano MG, Schott HC, Murphy AJ, Kaneene JB, Sellon DC, Hines MT, Hochstatter T, Bell JA, Mansfield LS.Equine protozoal myeloencephalitis (EPM) is a serious neurological disease of horses in Americans. Most cases are attributed to infection of the central nervous system with Sarcocystis neurona. Parasitemia has not been demonstrated in immunocompetent horses, but has been documented in one immunocompromised foal. The objective of this study was to isolate viable S. neurona from the blood of immunocompetent horses. Horses used in this study received orally administered S. neurona sporocysts (strain SN 37-R) daily for 112 days at the following doses: 100/day for 28 days, followed by 500/day for 2...
Yamaguchi K, Sawada T, Yamane S, Haga S, Ikeda K, Igata-Yi R, Yoshiki K, Matsuoka M, Okabe H, Horii Y, Nawa Y, Waltrip RW, Carbone KM.Borna disease virus (BDV) is a neurotropic pathogen that infects a wide variety of vertebrates. We have developed a new electrochemiluminescence immunoassay (ECLIA) for the detection of antibodies to BDV, using three synthetic peptides corresponding to the amino acid residues 3-20 and 338-358 of p40 and 59-79 of p24 peptide of BDV. Using the ECLIA, we examined serum samples for the presence of anti-BDV antibodies in 20 rats (experimentally BDV-infected and uninfected) and 38 horses (13 US horses, experimentally infected and uninfected, and 25 Japanese horses, feral and domestic). The ECLIA, pe...
Rawlinson RJ, Jones RT.The history and clinical findings of 1 horses with guttural pouch mycosis referred to us are described. The salient features of the history and clinical signs common to both cases were profuse spontaneous nasal haemorrhage, partial pharyngeal paralysis; subsequently bilateral nasal discharge containing food material, inability to drink and parotid pain became evident. One case made a gradual recovery with conservative medical treatment while the second case was destroyed and submitted for post-mortem, histopathological and microbiological examination. This examination failed to establish the i...
Wada S, Yoshinari M, Katayama Y, Anzai T, Wada R, Akuzawa M.A 2-year-old Thoroughbred filly presented with ocular pain and epiphora of the left eye. The pupil was miotic and the cornea edematous near the ventro-temporal limbus, but did not retain any fluorescein. The topical antibiotics and atropine and diclofenac, and systemic flunixin meglumine and antibiotic therapy did not resolve the condition. A pink and fleshy infiltrate developed near the limbus indicating nonulcerative keratouveitis. The anterior uveitis deteriorated as manifested by the presence of dyscoria, hypopyon, and organized fibrin in the anterior chamber. Ocular signs were improved by...
Weese JS, Saab M, Moore A, Cai H, McClure JT.To compare PCR and culture results for the detection of subspecies . Respiratory tract samples (N = 158) from horses being tested for Bacterial culture was carried out on samples from which was detected by quantitative real-time PCR. was isolated from 12 (7.6%) samples: 4/9 (44%) samples when the PCR cycle threshold (C) was ≤ 30, 7/30 (23%) when the C was 30.1 to 35, and 1/119 (0.8%) when the C was 35.1 to 40. The highest C sample from a sample that yielded a positive culture was 36.9. The optimal Youden's J value was at a C of 34.2, the same value as determined by number needed to misdi...
Leblanc MM, Pritchard EL.The effects of bovine colostrum, absorption of equine colostral immunoglobulins and age on phagocytic and serum opsonizing activity of nine clinically healthy foals were examined. Cells and serum were collected prior to suckling and at 7, 14 and 28 days of age. Seven foals had serum IgG concentrations greater than 600 mg/dl whereas two foals had less than 350 mg of IgG/dl. Phagocytic and serum opsonic activity of eight clinically ill foals with less than 400 mg of IgG/dl of serum were also examined before and after plasma transfusion. Phagocytic and serum opsonizing activities were evaluated b...