Topic:Piroplasmosis
Piroplasmosis is a tick-borne disease affecting horses, caused by the protozoan parasites Theileria equi and Babesia caballi. These parasites invade and multiply within the red blood cells of the host, leading to hemolytic anemia. Clinical signs of piroplasmosis in horses may include fever, lethargy, jaundice, and anemia, although some horses may remain asymptomatic carriers. Diagnosis is typically confirmed through blood tests, including serological assays and polymerase chain reaction (PCR) techniques. Piroplasmosis can impact equine health and performance, and it poses challenges for international horse movement due to quarantine regulations. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, pathogenesis, diagnostic methods, and management strategies for equine piroplasmosis.
Diagnosis of equine piroplasmosis in Xinjiang province of China by the enzyme-linked immunosorbent assays using recombinant antigens. The prevalence of equine piroplasmosis in Xinjiang province, China, was examined by enzyme-linked immunosorbent assays (ELISAs). A total of 70 serum samples were taken from horses pastured on three farms in western Xinjiang, and examined for diagnosis of equine Babesia equi (B. equi) infection and B. caballi infection by ELISAs using recombinant equi merozoite antigen 1 (EMA-1) and recombinant P48 antigen, respectively. Of the 70 samples, 28 (40.0%) and 17 (24.3%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 11 (15.7%) samples were positive f...
The role of international transport of equine semen on disease transmission. Despite the numerous benefits of having the capability to transport semen internationally, there are serious potential ramifications if that semen is contaminated with a communicable disease. Bacteria: Many commensal bacteria colonize the exterior of the stallion penis and are not regarded as pathogenic. They may be cultured from an ejaculate. Alterations of the normal bacterial flora on the exterior genitalia may cause the growth of opportunistic bacteria such as Klebsiella pneumonia, Pseudomonas aeruginosa, Streptococcus zooepidemicus, which, if inseminated, may cause infertility in suscepti...
Diagnosis of equine piroplasmosis in Brazil by serodiagnostic methods with recombinant antigens. Serum samples from horses in the States of Sao Paulo and Mato Grosso do Sul, Brazil were examined for diagnosis of equine piroplasmosis by both the latex agglutination test (LAT) and enzyme-linked immunosorbent assay (ELISA) with recombinant antigens. Of the 47 samples analyzed, 38 (81%) and 42 (90%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 35 (75%) samples were positive for both B. equi and B. caballi infections. These results indicate that equine piroplasmosis is widespread and therefore a cause for serious concern in the States of Sao ...
Validation of a competitive enzyme-linked immunosorbent assay for diagnosing Babesia equi infections of Moroccan origin and its use in determining the seroprevalence of B. equi in Morocco. A highly specific and sensitive competitive enzyme-linked immunosorbent assay for detection of specific antibody to Babesia equi in serum from equids was validated for use in Morocco. The assay is based on the specific inhibition of binding of a monoclonal antibody to a conserved epitope within a recombinant parasite peptide by serum from infected animals. The assay was compared to an established indirect immunofluorescence assay, with a concordance of 91%. The assay was used to determine seroprevalence for B. equi infections in donkeys and horses throughout Morocco. A total of 578 sera (163 h...
Could treatment of pregnant mares prevent abortions due to equine piroplasmosis? Treatment of pregnant mares to prevent abortions due to equine piroplasmosis is a novel idea practised empirically at some Thoroughbred studs in South Africa. This paper presents the results of an investigation to ascertain whether imidocarb dipropionate crosses the equine placenta. Three pregnant mares were injected intramuscularly with imidocarb and their foetuses were mechanically aborted at varying time intervals thereafter. Imidocarb was found in foetal blood at a level similar to that in the dam's blood, suggesting that imidocarb administered to the dam would be available for anti-parasi...
Procedurally similar competitive immunoassay systems for the serodiagnosis of Babesia equi, Babesia caballi, Trypanosoma equiperdum, and Burkholderia mallei infection in horses. Procedurally similar competitive enzyme-linked immunoassay (cELISA) methods were developed for the serodiagnosis of Babesia equi and Babesia caballi (piroplasmosis), Trypanosoma equiperdum (dourine), and Burkholderia mallei (glanders) infections in horses. Apparent test specificities for the B. equi, B. caballi, T. equiperdum, and B. mallei cELISAs were 99.2%, 99.5%, 98.9%, and 98.9%, respectively. Concordances and kappa values between the complement fixation (CF) and the cELISA procedures for the serodiagnosis of B. equi, B. caballi, T. equiperdum, and B. mallei infections in experimentally e...
Erythrocyte associated haemato-biochemical changes in Babesia equi infection experimentally produced in donkeys. Equine babesiosis, caused by Babesia equi and transmitted by ticks is of major economic importance in India. The adverse effects which B. equi organism and its metabolites inflict on red blood cells have not been reported. Erythrocytes were analysed for red cell membrane phospholipids, proteins and haemoglobin (Hb) concentration and plasma for malondialdehyde (MDA) in B. equi carrier donkeys before splenectomy (50% parasitaemia. Before splenectomy the mean values of membrane protein, phospholipids, plasma MDA and Hb were found to be 1.63 +/- 0.12 mg/ml PCV, 2.28 +/- 0.9 mg/ml PCV, 3.63 +/- 0.3...
Molecular detection of Babesia equi and Babesia caballi in horse blood by PCR amplification of part of the 16S rRNA gene. Babesia equi and Babesia caballi are tick-borne haemoparasites that may cause babesiosis of Equidae. In southern Europe B. equi is enzootic and infections may occur asymptomatically and more frequently than those due to B. caballi. Complement fixation test (CFT) is the official serological test for the diagnosis of equine babesiosis, but it has low sensitivity during early and latent stages of the disease. With the aim of developing more sensitive and rapid direct diagnostic alternatives, PCR systems that amplified DNA targets of 664 or 659 bp regions of the 16S rRNA genes were designed and de...
Pathogenesis of Babesia caballi infection in experimental horses. The present study was designed to investigate the role of cytokines in the pathogenesis of Babesia caballi in experimentally infected horses. The expression of cytokine mRNA was determined by using reverse transcription-polymerase chain reaction in two B. caballi-infected horses for 2 weeks after the infection. In one horse, there was up-regulation of interferon-gamma, tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 mRNAs, while in the second horse, expression of only TNF-alpha mRNA was up-regulated. No change was observed in interleukin-4 mRNA in both of the horses. To know the rela...
Babesia equi field isolates cultured from horse blood using a microcentrifuge method. Babesia equi, a causative agent of equine piroplasmosis, was isolated from horses in the Chaco Province of Argentina, a known piroplasmosis endemic region. Fifteen B. equi field isolates were acquired by culture from 23 actively working horses from 2 ranches. The horses appeared healthy with no clinical signs or histories indicative of equine piroplasmosis. All 23 horses had B. equi-specific antibody activity by the indirect fluorescent antibody test and 18 were also complement fixation test positive for B. equi. Equine erythrocytes were prepared for parasite culture using a microcentrifuge tu...
Prevalence of equine piroplasmosis in Central Mongolia. Antigen for the indirect fluorescent antibody test (IFAT) was routinely prepared from infected erythrocytes from horses experimentally infected with Babesia equi and Babesia caballi. With the successful establishment of in vitro cultures of B. equi and B. caballi, it is now possible to employ culture-derived antigens in this test. In this study, in vitro-propagated B. equi- and B. caballi-infected erythrocytes were used as antigen in the IFAT. Various modifications to an established protocol had to be implemented to allow repeatable results. Cultures with 3-4% parasitized erythrocytes were fou...
Serodiagnosis of Babesia equi infection–a comparison of Dot-ELISA, complement fixation test and capillary tube agglutination test. 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...
Case report: field-acquired subclinical Babesia equi infection confirmed by in vitro culture. A horse with no prior clinical history of equine piroplasmosis tested negative for Babesia caballi and Babesia equi in the complement fixation test before importation into the United States from France. After 5 years in residence in the United States, the animal tested serologically positive for B. equi by the complement fixation test, the immunofluorescent antibody test, and Western blot analysis. The carrier status of the horse was confirmed by culture of B. equi parasites. In vitro culture offers an efficient and comparatively inexpensive method to determine the carrier status of horses sus...
A sero-epidemiological survey of equine piroplasmosis in the northern and eastern Cape Provinces of South Africa. Serum samples from yearling Thoroughbred horses (n = 176) in the magisterial districts of Colesberg, Venterstad, and Wodehouse in the Northern and Eastern Cape Provinces were collected between September and November 1995 to determine the prevalence of antibodies to Babesia equi and Babesia caballi in these regions. Samples were examined for specific antibodies using the indirect fluorescent antibody test. The 95% confidence intervals for the prevalence of serum antibodies in the 3 districts combined varied from 47% to 61% for B. equi and from 26% to 40% for B. caballi. Antibody prevalence did ...
An account on equine babesioses. A review of the distribution of Babesia equi and Babesia caballi, the
transmission of these protozoa by ticks and the immune response of infected
horses, in addition to a brief survey of diagnostic. tests and chemotherapy.
Control of Babesia equi parasitemia. Infection of horses with the hemoprotozoan Babesia equi has been reported in southern Florida, US Virgin Islands, part of Asia, Russia, India, the Middle East, Europe, Africa, Australia, South America, Central America, Mexico, Philippine Islands and some Caribbean islands. The restrictions placed on the international movement of infected horses has refocused attention on potential methods to control or eliminate infection. Don Knowles here discusses the primary chemotherapeutic compounds that have been used; the current knowledge concerning immune responses that potentially contribute to contr...
Equine piroplasmosis an update on diagnosis, treatment and prevention. Two haemoprotozoan parasites, Babesia caballi and Babesia equi, can cause equine piroplasmosis. Due to the presence of potential tick vectors in areas so far unaffected by equine babesias, import and export regulations often require the serum testing of animals for evidence of infection. Although the complement fixation test (CFT) has been recommended for detecting the presence of antibodies to Babesia spp., it has been demonstrated to have several disadvantages, including false-positive results and low sensitivity for detecting latent infections. An enzyme-linked immunosorbent assay (ELISA) m...
Epidemiological aspects of equine babesioses in a herd of horses in Brazil. Epidemiological studies of Babesia equi and B. caballi were undertaken in a herd of 120 pastured horses in Rio de Janeiro, Brazil. The area where the horses were held was shown to be highly endemic for both Babesia spp., i.e. the prevalence of B. equi antibodies in horses aged 6 months or older ranged from 90.6% to 100% as determined by the immunofluorescence antibody (IFA) test, and the prevalence of B. caballi antibodies as determined by Western blot ranged from 59.4% to 65.5%. From the herd, 20 foals and their dams were selected to estimate the degree of tick infestation and the foals were ...
The development of Babesia (Theileria) equi (Laveran, 1901) in the gut and the haemolymph of the vector ticks, Hyalomma species. The development of the piroplasm Babesia equi was studied by light microscopy in the gut and the haemolymph of three different Hyalomma species during and after the nymphs had engorged on parasitaemic horses. The stock of B. equi used was isolated from a horse imported from Turkmenistan (CIS) in 1991. The existence of gamogony was identified by the occurrence of gamonts and gametes in the gut contents of the nymphs at between 3 and 4 days after infestation of the nymphs, before the ticks dropped off the experimentally infected horses. Zygotes and kinetes were observed in the intestinal cells f...
Suspected red maple (Acer rubrum) toxicosis with abortion in two Percheron mares. Horses develop severe and often fatal hemolytic anemia after ingesting dried leaves from red maple (Acer rubrum) trees. Toxicosis appears related to an unknown oxidant present in the dried or wilted leaves. This case report describes 2 horses that aborted and developed fatal hemolytic anemia after consuming wilted leaves from red maple (Acer rubrum). While an absolute diagnosis was not confirmed due to lack of proper antemortem and postmortem examinations, red maple toxicosis appeared a reasonable diagnosis based on clinical signs and laboratory findings. Other differentials include equine inf...
Protein characterization of Babesia equi piroplasms isolated from infected horse erythrocytes. Proteins of Babesia equi piroplasms were characterized. The piroplasms of B. equi were purified by lysis of infected horse erythrocytes with N2 gas cavitation followed by separation in Percoll density-gradient centrifugation. The relative molecular weights (Mr) of major proteins separated by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 18, 28, 30, 41, 43, 54, 66.5, and 96 kDa. Immunoblot analysis using serum from an experimentally infected horse revealed six immunodominant proteins of 15, 18, 28, 30, 41, and 96 kDa. Two immunodominant proteins of 18 and 28 kDa...
Efficacy of buparvaquone as a therapeutic and clearing agent of Babesia equi of European origin in horses. We evaluated the efficacy of buparvaquone in eliminating infection with Babesia equi of European origin in carrier horses and in splenectomized horses with experimentally induced acute infection. When administered at the rate of 5 mg/kg of body weight, IV, 4 times at 48-hour intervals, buparvaquone prompted rapid abatement of parasitemia. However, secondary and tertiary recrudescent parasitemias invariably returned with establishment of the carrier state. Buparvaquone, at the dosage evaluated, had transitory therapeutic efficacy against acute B equi infection in splenectomized horses, but was ...
Transmission and diagnosis of equine babesiosis in South Africa. The transmission and prevalence of Babesia equi and B. caballi are being studied. Rhipicephalus evertsi mimeticus an ixodid tick from Namibia was identified as a new vector of B. equi, however, R. turanicus, previously reported to be a vector, failed to transmit both B. equi and B. caballi in the laboratory. The accurate diagnosis of B. caballi is being investigated because the nature of its low level parasitaemia does not allow easy detection in thin blood smears, routinely used for diagnosis, by clinicians. Consequently its role as a pathogen remains obscure. The importance of identifying in...