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.
Costa LR, Santos IK, Issel CJ, Montelaro RC.Cardinal features of equine infectious anemia (EIA) include fever, hemolytic anemia and thrombocytopenia during the acute phase of the disease, and cachexia and anemia seen during the chronic phase. These signs are thought to result from the release of inflammatory cytokines such as TNF-alpha. In order to determine if TNF-alpha has a role in the pathogenesis of acute EIA and vaccine-induced disease enhancement, we measured plasma concentrations of TNF-alpha in ponies immunized with virus enriched major core protein-p26 and/or experimentally infected with EIAV. Naturally infected inapparent EIA...
Eysker M, Boersema JH, Grinwis GC, Kooyman FN, Poot J.The efficacy of a 2% moxidectin equine gel at a dosage rate of 0.4 mg kg-1 was evaluated in a controlled trial at Utrecht University. Twelve yearling castrated male Shetland ponies grazed a pasture of 2 ha from May 1994 until housing in November. Six ponies were treated with moxidectin, whereas the others served as non-treated controls. Necropsy was carried out 35 days after treatment. Greater than 99% efficacy of moxidectin was observed on faecal egg output. No effect of moxidectin was observed on mucosal inhibited early cyathostome L3 (EL3) or on the total numbers of mucosal developing stage...
Paweska JT.Clinical, virological and serological responses were investigated in five pregnant donkey mares after experimental exposure to the South African asinine-94 strain of equine arteritis virus (EAV), and the duration of maternal immunity to EAV was studied in their foals. In four intranasally inoculated mares, fever with maximum rectal temperatures of 39.1-40.7 degrees C was recorded 2-11 d after challenge. All the inoculated mares developed mild depression, and a serous ocular and nasal discharge; in three mares mild conjuctivitis was observed. The virus was recovered from the nasopharynx and fro...
Haites RE, Muscatello G, Begg AP, Browning GF.The prevalence of the plasmid-encoded virulence-associated gene (vapA) of Rhodococcus equi, as determined by PCR, was found to be 98% in isolates from 154 foals with pneumonia, confirming the strong association of vapA with virulence. The vapA genes from 60 representative isolates were compared by digestion with the restriction endonuclease HinfI, and no evidence of sequence variation was detected.
Chesters PM, Allsop R, Purewal A, Edington N.Results from Southern hybridization and PCR amplification experiments using a randomly synthesized reverse transcription-PCR product showed that peripheral blood leukocytes from horses showing no clinical signs of disease expressed a putative latency-associated transcript antisense to and overlapping the 3' end of the equid herpesvirus 1 (EHV-1) immediate-early gene (gene 64). A PCR product derived from this transcript has > or =96% identity with the published EHV-1 sequence. In situ hybridization studies of equine bronchial lymph nodes corroborated these findings and are consistent with re...
Hammond SA, Cook SJ, Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a natural model system by which immunological control of lentivirus infections may be studied. To date, no detailed study addressing in parallel both the humoral and cellular immune responses induced in horses upon infection by EIAV has been conducted. Therefore, we initiated the first comprehensive characterization of the cellular and humoral immune responses during clinical progression from chronic disease to inapparent stages of EIAV infection. Using new analyses of antibody avidity and antibody epitope conformation dependence that had not been...
Madić J, Hajsig D, Sostarić B, Curić S, Seol B, Naglić T, Cvetnić Z.An abortion outbreak occurred in a herd of 38 horses, 26 of which were pregnant mares. Twenty-one mares aborted between 5-10 months of gestation. In no case were there indications of impending abortion. Pathoanatomical, histopathological, virological and bacteriological examinations were carried out on 4 aborted fetuses. Histopathology identified Gram-negative bacteria compatible with salmonella in all 4 placentae. By subsequent bacteriological examination Salmonella abortusequi was isolated as the single causative agent in each case. Nonmotile Salmonella abortusequi with antigenic formula 4,1...
Del Piero F, Wilkins PA, Lopez JW, Glaser AL, Dubovi EJ, Schlafer DH, Lein DH.Clinical, pathological, immunohistochemical, serological and microbiological findings are described for 2 geographically and temporally distinct equine arteritis virus (EAV) epidemics in newborn foals. Outbreak A occurred at a commercial Standardbred breeding facility; Outbreak B began in a group of research animals. Clinical signs were severe and primarily referable to the respiratory tract. Fever and leucopenia and/or thrombocytopenia were observed in foals surviving for more than 24 h. The most common gross pathological findings were limited to the respiratory tract. Common histopathologica...
Sailleau C, Moulay S, Cruciere C, Laegreid WW, Zientara S.A reverse transcription-polymerase chain reaction (RT-PCR) assay followed by dot-blot hybridisation was used to detect African horse sickness virus (AHSV); the primers employed amplified the S7 gene that encodes the VP7 protein. The RT-PCR assay was compared with virus isolation for detecting AHSV in blood samples form horses experimentally infected with AHSV-4 and AHSV-9. The influence of sample storage and transportation and the effects of two anticoagulants (EDTA and heparin) were also studied. RT-PCR results were obtained within 48 hours as opposed to a minimum of 15 days for virus isolati...
Machida N, Taniguchi T, Nakamura T, Kiryu K.Twenty-five aborted equine fetuses infected with equid herpesvirus 1 (EHV-1) were examined cardio-histopathologically. The main changes in the heart consisted of interstitial myocarditis and intramyocardial vascular lesions accompanied by degeneration and necrosis of the cardiac myocytes. Vascular pathology of intramyocardial small arteries and arterioles was characterized by endothelial cell necrosis and fibrinoid changes in the media. Eosinophilic intranuclear inclusion bodies characteristic of herpesvirus infection were detected in the myocardial cells and macrophages within and around the ...
Ringger NC, Edens L, Bain P, Raskin RE, Larock R.A 5-year-old Thoroughbred mare presented with a 4 week history of weight loss, fever and leukopenia. Rectally, a large active foetus, thickened spleen and an abdominal mass were palpated. Leukopenia, mild anaemia, marked thrombocytopenia and hyperfibrinogenaemia were found. Cytology and cytochemical staining of a bone marrow aspirate supported a diagnosis of acute myelogenous leukaemia. The mare deteriorated despite medical therapy and was humanely euthanased.
Birch-Machin I, Rowan A, Pick J, Mumford J, Binns M.The nucleotide sequence of the nonstructural protein NS1 of the influenza virus A/equine 2/Suffolk/89 was determined and found to be 97% identical to that of A/equine 2/Miami/63. A similar level of identity was shown for the deduced NS1 amino acid sequence. The NS1 gene was expressed, in its entirety and in part, as fusion proteins with glutathione S-transferase using the pGEX-3X expression vector. Antibodies to NS1 protein were detected in serum samples from ponies experimentally infected with influenza virus, but not in animals vaccinated with whole inactivated virus or in unprimed control a...
Hobo S, Oikawa M, Kuwano A, Yoshida K, Yoshihara T.To study the effects of extended transportation on the composition of bronchoalveolar lavage fluid (BALF) obtained from horses. Methods: 30 horses (14 males, 16 females: 25 Thoroughbreds and 5 Thoroughbred-Arabian cross-breds; 27 to 30 months old) without a history or clinical signs of respiratory tract disease. Bronchoalveolar lavage was performed on nontransported control horses (groups 1 and 2) and transported horses (group 3). Methods: 20 horses were used to determine the effect of 41 hours of transportation on the composition of BALF (group 3). Bronchoalveolar lavage fluid was analyzed fo...
McAnulty JF, Stone WC, Darien BJ.The purpose of this study was to examine the effects of ischemia and reperfusion on the biochemical integrity of equine colonic mucosa to assess the relative roles of ischemic- and reperfusion-induced damage. Methods: Two hours of no-flow ischemia experimentally induced by 720 degrees counterclockwise ascending colon volvulus followed by 2 hours reperfusion after derotation. Methods: Ten ponies. Methods: Ascending colon biopsies were obtained every hour for measurement of mucosal adenosine triphosphate (ATP), water, sodium, and potassium content. Additional samples were homogenized for assay o...
Kumar S, Malhotra DV, Dhar S.The present study aimed to develop Dot-ELISA, complement fixation test (CFT) and capillary tube agglutination test (CAT) for serodiagnosis of Babesia equi infection and to compare their sensitivity with each other. For this study, sequential serum samples were collected from four donkeys experimentally infected with B. equi up to 90 days post infection (P.I.). B. equi antigen was prepared from the blood of a donkey showing more than 80% parasitaemia. Dot-ELISA, CF and CA tests were standardized as per the standard method. While performing CFT, it was observed that CFT standardized for the donk...
Borchers K, Wolfinger U, Lawrenz B, Schellenbach A, Ludwig H.Neuronal and lymphoid tissues of 15 randomly selected horses were analysed post mortem by liquid nested-PCR to study the tropism of equine herpesvirus 4 (EHV-4). In four animals the trigeminal ganglia and in one case the lung were positive. Using a direct in situ PCR the EHV-4 genome was localized in the nuclei of neurons and in the bronchiolar as well as alveolar epithelium of the lung. In none of these tissues could infectious virus or viral antigens be detected. Applying the more sensitive liquid RT-PCR, however, an acute infection was demonstrated in one of the trigeminal ganglia by amplif...
Rizvi SM, Slater JD, Wolfinger U, Borchers K, Field HJ, Slade AJ.The distribution of equine herpesvirus 2 (EHV-2) DNA within neurological and lymphoid tissues from 12 EHV-2 seropositive Welsh mountain ponies was determined by PCR. The lymphoid sites sampled in this study were almost universally PCR positive, thus confirming the existing virus co-cultivation data which suggest that the lymph nodes draining the respiratory tract are the main reservoirs of EHV-2 DNA. In addition, EHV-2 DNA was also detected, albeit with lower frequency, within both the peripheral and central nervous systems (PNS and CNS) of these animals. Of the CNS sites sampled 11% were PCR-...
Smith KC.Abortion or neonatal disease may follow infection with several alpha, beta and gamma-herpesviruses. The alpha-herpesvirus, equid herpesvirus-1 (EHV-1), causes single or epizootic abortions or neonatal deaths in equids, and the closely related virus EHV-4 causes sporadic equine abortions. In cattle, the alpha-herpesviruses, bovine herpesvirus-1 (infectious bovine rhinotracheitis virus) and bovine herpesvirus-5 (bovine encephalitis virus), and a gamma-herpesvirus, bovine herpesvirus-4, have all been implicated as causes of abortion. In pigs, suid herpesvirus-1 (SHV-1: pseudorabies virus), an alp...
Bonilla E, Valero-Fuenmayor N, Pons H, Chacín-Bonilla L.We investigated whether the administration of melatonin (MLT) reduces the death rate and evolution of the disease in mice infected with Venezuelan equine encephalomyelitis (VEE) virus. Our results show that, MLT protects mice infected with the virus. The mortality rate was reduced from 100% to 16% merely by increasing the dose from 0 to 1000 micrograms/MLT per kg body weight MLT significantly postponed the onset of the disease and death by several days. In surviving mice very high titres of VEE virus IgM antibodies were found seven weeks after virus inoculation. MLT significantly reduced VEE v...
Glaser AL, Chirnside ED, Horzinek MC, de Vries AA.Equine arteritis virus (EAV) is a small, enveloped, positive-stranded RNA virus, in the family Arteriviridae , W.H.ich can infect both horses and donkeys. While the majority of EAV infections are asymptomatic, acutely infected animals may develop a wide range of clinical signs, including pyrexia, limb and ventral edema, depression, rhinitis, and conjunctivitis. The virus may cause abortion and has caused mortality in neonates. After natural EAV infection, most horses develop a solid, long-term immunity to the disease. Marzz and geldings eliminate the virus within 60 days, but 30 to 60% of acut...
Parlevliet JM, Bleumink-Pluym NM, Houwers DJ, Remmen JL, Sluijter FJ, Colenbrander B.Contagious equine metritis (CEM) is a sexually transmissible disease in mares. Although the disease is commonly diagnosed by culturing the causative bacterium Taylorella equigenitalis (T. equigenitalis) . false negative results do occur. A recently developed Polymerase Chain Reaction (PCR) assay, however, appeared to be much more sensitive, with initial results indicating an unexpected high incidence of the agent in selected horses. In this study, samples from 107 randomly selected mares with no clinical signs of CEM submitted for conventional culture were all negative for T. equigenitalis . b...
Tschetter JR, Byrne KM, Perryman LE, McGuire TC.Horses infected with equine infectious anemia virus (EIAV) have recurrent episodes of viremia which are eventually controlled, but the immune mechanisms have not been identified. Antibodies were detected to the surface of EIAV-infected cells within 1 month postinfection and remained for at least 3.5 years postinfection. These antibodies recognized cell surface-exposed envelope (Env) glycoproteins, but could not mediate antibody dependent cellular cytotoxicity (ADCC) using EIAV-WSU5-infected equine kidney (EK) cells as targets and peripheral blood mononuclear cells (PBMC) or polymorphonuclear c...
Wood JL, Chanter N, Newton JR, Burrell MH, Dugdale D, Windsor HM, Windsor GD, Rosendal S, Townsend HG.Lower respiratory tract disease developed in a group of racehorses in training between two and six years of age. Disease was observed in 22 of 25 horses for which full records were available. Seroconversion to Mycoplasma felis was demonstrated by indirect haemagglutination assay in 19 of 22 paired sera and high titres (> or = 64) were found in convalescent sera from the three remaining horses. Evidence of respiratory viral infection was confined to seroconversions to equine herpesvirus-4 in two of the horses. Tracheal wash samples, taken from four horses with visibly increased tracheal muco...
Uhlinger C.Leukoencephalomalacia in horses is caused by fumonisins. These mycotoxins are produced by Fusarium spp. that contaminate corn and corn byproducts while in the field. The most common clinical presentation is a multifocal neurologic disease that affects multiple horses in a herd. Although the majority of affected horses die, treatment directed at decreasing inflammation and edema in the CNS may result in recovery in some animals.
Greppi MC, Guillot J, Melloul E, Bourdoiseau G, Lepage O, Cadoré JL.Guttural pouch mycosis (GPM) is a rare but potentially life-threatening condition in horses. GPM is caused by a fungal invasion into the mucosal lining of the guttural pouches and, frequently, the associated neurovascular structures. Although several species of fungi have been associated with this disease, Aspergillus spp. appear to be the most common isolated from the guttural pouches. However, it remains unclear which are the predisposing factors leading to the development of the infection. The objectives of the present study were to experimentally reproduce an infection by Aspergillus fumig...
Sentsui H, Inoshima Y, Murakami K, Akashi H, Purevtseren B, Pagmajav O, Sugiura T.Cross reactivity of equine infectious anemia virus (EIAV) antigen prepared using a recombinant baculovirus containing the p26 gene of strain P337-V70 was examined by the agar gel immunodiffusion (AGID) test and enzyme-linked immunosorbent assay (ELISA). Serum samples serially collected from 13 horses experimentally infected with six different EIAV strains (two or three horses per strain) were subjected to the test. Positive reactions were observed in the AGID test and ELISA before or soon after the first feverish period and continued persistently in most of the horses. The results with recombi...
Bertram TA, Jensen AE.Morphology and function of equine neutrophils were evaluated after combination with contagious equine metritis organism (CEMO) or 1 of 2 CEMO lipopolysaccharides (LPS). The 2 LPS (LPS-a; LPS-p) isolated from the CEMO contained 14- and 16-carbon fatty acids, ketodeoxyoctanate, hexose, and heptose, but were morphologically distinct. Neutrophils exposed to LPS had fewer granules, whereas those exposed to CEMO had more granules than did the controls (phosphate-buffered saline solution). Neutrophil iodination was significantly increased with 10 and 25 micrograms of LPS-a, but not significantly alte...
Abreu RA, Weiss RR, Thomaz-Soccol V, Locatelli-Dittrich R, Laskoski LM, Bertol MA, Koch MO, Alban SM, Green KT.Sera from 112 mares from 5 horse-breeding farms was examined for the presence of antibodies to Neospora caninum and Toxoplasma gondii by an indirect fluorescent antibody test (IFAT), as well as from dogs and cattle present on these properties for the presence of antibodies to N. caninum. Among the 112 mares, 35 had a history of reproductive problems in the last breeding season and 77 had no reproductive problems. The rates of seroprevalence of N. caninum in mares with and without a history of reproductive problems were 25.71% and 6.49% and from T. gondii 2.85% and 1.29%, respectively. In dogs ...
Lorenzo-Figueras M, Pusterla N, Byrne BA, Samitz EM.To evaluate the effectiveness of a commercial conventional blood culture system (BCS), a commercial resin-containing BCS, and a commercial lysis-centrifugation-based BCS for the recovery of Escherichia coli from equine blood samples inoculated with that organism. Methods: Samples of blood obtained from a clinically normal horse that were inoculated with E coli. Methods: Blood samples were aseptically collected and inoculated with an E coli specimen (50 CFUs/mL) that had been previously isolated from a foal with sepsis. Subsequently, samples were spiked with gentamicin at a concentration of 30 ...
Ganjam VK, McLeod C, Klesius PH, Washburn SM, Kwapien R, Brown B, Fazeli MH.The reaction between ovarian hormones and experimental uterine infection (Streptococcus zooepidemicus) was investigated in 3 groups, each containing 6 ovariectomized mares. Group 1 served as controls ('anoestrus'), Group 2 mares were injected with oestrogen ('oestrus') and Group 3 with progesterone ('dioestrus') over a period of 5 weeks. All mares received an intrauterine inoculation of the bacteria 1 week after the start of hormonal treatment, and the results of the challenge were examined by endometrial biopsy and swabs once weekly. At the end of Week 1 no bacteria were recovered from the ma...
Mosichuk AP, Smith JS, Tatarniuk DM, Troy JR, Kreuder AJ.Septic synovitis is a critical orthopedic condition in horses. Early intervention is key, with antibiotic therapy typically initiated prior to culture and susceptibility reports becoming available. The pharmacokinetics of several antibiotics have been studied in horses for use in intravenous regional limb perfusion (IVRLP) for septic synovitis, including the carbapenem antibiotic, meropenem. For a variety of factors, some veterinary clinicians may select IVRLP meropenem as therapy for these cases. Meropenem is a vital antibiotic in human medicine, making veterinary use divisive. However, verif...
Infectious causes of myositis are reported relatively uncommonly in horses. Among them, bacterial causes include subsp. , , spp. spp, and . Infection can be spread to muscles via haematogenous or extension from skin lesions. Parasitic myositis has also been documented. In this report, a 12 year-old Italian Quarter Horse mare presented with diffuse subcutaneous nodules and masses ranging from 2 × 3 to 5 × 20 cm in size, and adherent to subcutis and muscles that were first macroscopically and cytologically diagnosed as pyogranulomas. Subsequently, histological, molecular, bacteriological, a...
Ruggles AJ, Ross MW.Medical records of 28 horses with impaction of the small colon were reviewed; 20 horses were admitted during the winter months. Diagnosis of small-colon impaction was made in 21 horses by rectal examination, and in 7 horses at exploratory celiotomy. Ten horses were treated medically, and 18 were treated surgically. Horses that were treated surgically were more likely to have abdominal distention than were those that responded to medical treatment (P less than 0.025). Signs of greater degree of abdominal pain and higher heart rate were seen in horses treated surgically, but these values were no...
McGuire TC, Banks KL, Evans DR, Poppie MJ.Agammaglobulinemia was diagnosed in a 1-year-old Thoroughbred horse on the basis of the following observations: (1) absence of serum immunoglobulins M, A, and G(T); (2) small amounts of serum immunoglobulin G (16 mg/100 ml); (3) absence of specific antibody in the serum of the horse following immunization and challenge exposure to 2 antigens; (4) absence of plasma cells, primary follicles, and germinal centers in a lymph node removed after antigenic stimulation; (5) absence of "natural" serum antibodies to rabbit-erythrocytes which were easily detectable in age-matched control horse serums; an...
Mawhinney I, Errington J, Stamper N, Torrens N, Engelsma MY, Roest HIJ.Sets of genital swabs are routinely taken from horses to screen for the presence of Taylorella equigenitalis, the cause of contagious equine metritis. Typically, two to four different sites are swabbed at a time and tested by culture or PCR. Objective: This study explored the feasibility of pooling these swabs for a single PCR test per animal instead of testing each swab individually. Methods: In vitro. Methods: PCR signal strengths (Ct values) from 149 historical PCR positive genital swabs, together with historical data on the number of swabs in a set expected to be positive, were used to ass...
Dewes HF, Townsend KG.Two horses repeatedly underwent episodes of frenzy characterised by extreme discomfort and hyperactivity. Within 2 days of an attack the lower extremities of both hind legs of one subject were uniformly swollen, while on the second subject skin lesions erupted 3-4 days after an attack and swelling persisted for 2-3 weeks. Filariform larvae of Strongyloides westeri were cultured from soil and sawdust where the subjects were kept. Larvae were cultured from soil of low pH (4.5-5.8) but were absent from neutral or alkaline soils. Larvae were found in sawdust with a wide pH range. It is thought tha...
McClure S, Sibert G, Hallberg J, Bade D.The efficacy and safety of sustained release ceftiofur administered twice, 4 days apart, for treatment of horses with naturally acquired Streptococcus equi subsp. zooepidemicus (Strep. zoo.) pneumonia was evaluated in a multicenter, placebo-controlled, double-blinded, randomized clinical trial. The study included 373 horses (278 treated and 95 placebos) with naturally acquired pneumonia. Inclusion in the statistical analyses for treatment efficacy for Strep. zoo. required recovery of ≥10(4) CFU/mL of Strep. zoo. on the primary isolation plate which resulted in 201 cases (145 treated and 56 p...
Salmonella enterica subsp. enterica serovar Abortusequi (S. Abortusequi) is a serotype restricted to equines, which produces abortion outbreaks. Nowadays the disease is being reported in different countries including Argentina thus generating an important impact in the equine industry. Molecular characterization of the 95 kb virulence plasmid and the spvC gene of S. Abortusequi demonstrated their importance in the pathogenicity of the serotype. In the last decades, high clonality of S. Abortusequi was identified in Japan, Mongolia and Croatia. Objective: The aim of this work was to characteriz...
Sallé G, Cortet J, Koch C, Gascogne T, Reigner F, Cabaret J.Drug resistance in equine gastro-intestinal parasitic nematodes has been reported throughout the world. While the focus is usually put on cyathostomins, observations of macrocylic lactone failure against Oxyuris equi have accumulated over the last decade. Here we report the failure of ivermectin in the control of O. equi in an experimental Welsh pony herd. In a first trial, 6 ponies previously drenched with moxidectin and showing patent O. equi infections were administered ivermectin and subsequently monitored for O. equi egg excretion over one month. This trial demonstrated a failure of iverm...
Tanaka Y, Adilbish A, Koyama K, Bayasgalan MO, Horiuchi N, Uranbileg N, Watanabe K, Purevdorj B, Gurdorj S, Banzragch B, Badgar B, Suganuma K....Dourine is a deadly protozoan disease in equids caused by infection with Trypanosoma equiperdum. Neurological signs in the later stage of infection may be caused by peripheral polyneuritis and related axonal degeneration. This neuritis involves T lymphocytes, B lymphocytes, and macrophages, and is observed in cases without obvious neurological signs. However, the pathogenesis of neuritis remains unclear. We identified M2 macrophages and CD8 T cells as the predominant phenotypes in neuritis of dourine-affected horses with or without neurological signs. In contrast, the populations of M1 macroph...
Debey MC, Bailie WE.Horse farms in Kansas were surveyed for the incidence of Rhodococcus equi. Fecal specimens and soil or cobweb samples were collected from each farm and cultured on selective media. One control farm (with no history of R. equi infection), one farm which had an outbreak 3 and 4 years previously and 2 farms which had R. equi-infected foals that season were surveyed. In addition, fecal samples from 21 horses hospitalized in the Kansas State University Veterinary Hospital were cultured. There was no significant difference in the incidence of R. equi in fecal samples from the 2 farms with recent dis...
Kubota T, Inaba Y, Uwatoko K, Akashi H, Fukunaga Y.Equine arteritis virus (EAV) grown on RK13 cell cultures was tested for hemagglutination (HA) with erythrocytes from a variety of species at 4 degrees C, room temperature and 37 degrees C. HA was observed at all temperatures with erythrocytes from mouse and chicken but not with those of cattle, horse, rabbit, guinea pig, mongolian gerbil, goose or chick embryo. Chickens showed an individual variation in agglutinability of their erythrocytes, requiring selection of birds to obtain erythrocytes for HA. The HA activity was enhanced by treatment of virus materials with Tween 80 followed by treatme...
Chapman MR, Kearney MT, Klei TR.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...
Andersen UV, Haakansson IT, Roust T, Rhod M, Baptiste KE, Nielsen MK.Strongyle and trichostrongyle parasites are ubiquitous nematodes of grazing livestock. Several molecular diagnostic tests are based upon measuring and quantifying DNA obtained from parasite eggs. It is well known that such eggs undergo development during storage, but it remains unknown to which extent developmental stages can affect the variation of diagnostic test results. This study investigated the influence of developmental stages of strongyle eggs on the variation real-time polymerase chain reaction (PCR) results. Mixed species strongyle eggs were obtained from the faeces of a naturally i...
Müller I, Khanakah G, Kundi M, Stanek G.Grazing animals are continuously exposed to tick bites. Consequently, one may expect that horses will become infected with the various pathogens carried by ticks including Borrelia burgdorferi sensu lato. Whether horses may develop clinical disease due to this pathogen is controversially discussed. We were interested to learn about the infection of horses with Borrelia burgdorferi sensu lato within one season by studying the dynamics of the humoral immune response in paired blood samples. The majority of horses examined were Lipizzaner from the stud farm in Piber/Steiermark, and from the Spani...
Halliwell RE, Hines MT.A radioimmunoassay was developed for detection of immunoglobulin in the aqueous of normal horses and horses with intraocular diseases. Levels of albumin were detected by radial immunodiffusion. Results of assays on samples from normal eyes from which aqueous was obtained by paracentesis under anesthesia were 32.10 +/- 21.50 microgram/ml for IgG, 0.05 +/- 0.01 microgram/ml for IgM, 0.04 +/- 0.02 microgram/ml for IgA and 34.0 +/- 38.0 microgram/ml for albumin. Results in 138 normal eyes sampled post mortem were 41.56 +/- 38.65 microgram/ml for IgG, 0.18 +/- 0.43 microgram/ml for IgM, 0.46 +/- 1....
Leber R, Wiler R, Perryman LE, Meek K.V(D)J rearrangement is the molecular mechanism by which an almost limitless number of unique immune receptors is generated. V(D)J rearrangement involves two DNA breaks and religations resulting in two DNA joints; coding and signal joints. If V(D)J recombination is impaired (as in murine SCID (C.B-17 mouse] or RAG [Recombinase Activating Genes) deficient mice), B lymphocyte and T lymphocyte development is blocked and severe immunodeficiency results. The first animal model of SCID was reported in Arabian foals in 1973. Recently we demonstrated that the mechanistic defect in SCID foals is V(D)J r...
Collobert-Laugier C, Hoste H, Sevin C, Chartier C, Dorchies P.From December 1998 to March 2000, caecum and ascendant colon of 42 horses naturally infected with cyathostomes were collected during routine necropsy or from a local slaughterhouse. Changes in the numbers of mucosal and submucosal mast cells (MMC and SMMC), intraepithelial, mucosal and submucosal eosinophils (IE, ME and SME) in the large intestine were investigated by histochemical techniques in relation to the worm burdens. The effect of age was examined in three subgroups: 6-24-month-old horses (group 1), 2-10-year-old horses (group 2) and horses more than 10 years of age (group 3). No globu...
Zheng J, Guo JG, Wang XF, Zhu HQ.To study the relationship between the livestock trade and schistosomiasis transmission and to provide an evidence for making a strategy of schistosomiasis control in mountainous areas. Methods: A retrospective survey and analysis was conducted to investigate the prevalence of schistosomiasis in both humans and livestock (cattle, horses, mules, donkeys and pigs), and the number and migration of livestock in Weishan County, Yunnan Province in 1980-1991. Results: A positive correlation was found between the infection rate of residents and the numbers of livestock migration (R = 0.9151, P < 0.0...
Davis SW, Speer CA, Dubey JP.Asexual stages of Sarcocystis neurona were seen in cultured bovine monocytes (M617) inoculated with tissue homogenates from the spinal cord of a horse with naturally acquired protozoal myelitis. Organisms first were observed as intracytoplasmic schizonts and later as motile extracellular zoites capable of infecting surrounding M617 cells. Parasites most often occurred as clusters of merozoites dispersed throughout the host cell cytoplasm; however, schizonts also contained merozoites arranged in a radial fashion surrounding a prominent residual body. Schizonts divided by endopolygeny. The paras...
Wang Y, Zhang LP, Li J, Li DD, Zhang Q, Li C.The aim of this study was to determine the seroprevalence of Babesia caballi and Theileria equi in horses imported into Shanghai port. Between 2018 and 2019, 344 horse sera samples were collected and tested for B. caballi and T. equi, using commercially available kits. Only one B. caballi seropositive sample was detected. To the best of our knowledge, this is the first report of a B. caballi seropositive in imported horses at Shanghai port, which reflects the importance of monitoring piroplasmosis seroprevalence in imported horses.
Karamalla ST, Gubran AI, Adam IA, Abdalla TM, Sinada RO, Haroun EM, Aradaib IE.African horse sickness virus (AHSV) is an infectious non contagious insect-transmitted double-stranded (ds) RNA orbivirus of the family Reoviridae. AHSV causes an often fatal hemorrhagic infection with high mortality among selected breeds of Arabian horses. This study was conducted to avail some information with regard to the prevalence and associated risk factors of AHSV among ecotype breeds of horses in central Sudan. Methods: Sera were collected from 320 horses, which were selected randomly from four localities and employed in the study. A competitive enzyme-linked immunosorbent assay (cELI...
Araujo JM, Araújo JV, Braga FR, Tavela Ade O, Ferreira SR, Soares FE, Carvalho GR.Strongyloides westeri is the most prevalent nematode among equines aged up to four months and causes gastrointestinal disorders. The objective of this study was to observe the control of infective S. westeri larvae (L3) by the nematophagous fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34) after passage through the gastrointestinal tract of female donkeys. Twelve dewormed female donkeys that were kept in stables were used. Two treatment groups each comprising four animals received orally 100 g of pellets made of sodium alginate matrix containing a mycelial mass of either...
Pinna A, Martins G, Souza G, Lilenbaum W.The aim of this study was to demonstrate that seroreactivity against Leptospira is significantly associated to the reproductive efficiency of recipient mares of an embryo transfer (ET) programme. A serosurvey was conducted from August 2007 to March 2009 in five herds from Rio de Janeiro, Brazil, with high rates of reproductive failure, as early embryonic death (>12%), abortion (>12%) and perinatal death. Detailed information about the losses was obtained from practitioner. A total of 338 recipient mares were tested by microscopic agglutination test, and 226 (66.9%) were seroreactive, mainly ag...
