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We recently described a protein O-glycosylation pathway conserved in all species of the Burkholderia genus that results in the synthesis and incorporation of a trisaccharide glycan to membrane-exported proteins. Here, we exploited this system to construct and evaluate a diagnostic tool for glanders. Burkholderia mallei, the causative agent of glanders, is a highly infectious and fatal zoonotic pathogen that infects horses, mules, donkeys, and occasionally humans. A highly sensitive and specific diagnostic tool is crucial for the control, elimination, and eradication of B. mallei infections. We constructed plasmids carrying synthetic genes encoding a modified, previously unannotated Burkholderia glycoprotein containing three glycosylation sequons fused to the cholera toxin B-subunit. The resulting proteins were glycosylated in the B. cenocepacia K56-2 parental strain, but not in glycosylation-deficient mutants, as determined by SDS-PAGE and fluorescent lectin blots. One of these glycoproteins was used as an antigen in ELISA and western blots to screen a panel of serum samples collected from glanders-infected and healthy horses, which were previously investigated by complement fixation test and indirect ELISA based on a semi-purified fraction of B. mallei. We show that ELISA and western blot assays based on our glycoprotein antigen provide 100% specificity, with a sensitivity greater than 88%. The glycoprotein antigen was recognized by serum samples collected from patients infected with B. pseudomallei, B. mallei, B. multivorans, and B. cenocepacia. Our results indicate that protein O-glycosylation in Burkholderia can be exploited as a biomarker for diagnosis of Burkholderia-associated infections.

We recently described a protein O-glycosylation pathway conserved in all species of the Burkholderia genus that results in the synthesis and incorporation of a trisaccharide glycan to membrane-exported proteins. Here, we exploited this system to construct and evaluate a diagnostic tool for glanders. Burkholderia mallei, the causative agent of glanders, is a highly infectious and fatal zoonotic pathogen that infects horses, mules, donkeys, and occasionally humans. A highly sensitive and specific diagnostic tool is crucial for the control, elimination, and eradication of B. mallei infections. We constructed plasmids carrying synthetic genes encoding a modified, previously unannotated Burkholderia glycoprotein containing three glycosylation sequons fused to the cholera toxin B-subunit. The resulting proteins were glycosylated in the B. cenocepacia K56-2 parental strain, but not in glycosylation-deficient mutants, as determined by SDS-PAGE and fluorescent lectin blots. One of these glycoproteins was used as an antigen in ELISA and western blots to screen a panel of serum samples collected from glanders-infected and healthy horses, which were previously investigated by complement fixation test and indirect ELISA based on a semi-purified fraction of B. mallei. We show that ELISA and western blot assays based on our glycoprotein antigen provide 100% specificity, with a sensitivity greater than 88%. The glycoprotein antigen was recognized by serum samples collected from patients infected with B. pseudomallei, B. mallei, B. multivorans, and B. cenocepacia. Our results indicate that protein O-glycosylation in Burkholderia can be exploited as a biomarker for diagnosis of Burkholderia-associated infections. [ABSTRACT FROM AUTHOR]

• Equine granulocytic anaplasmosis is typically caused by Anaplasma phagocytophilum. • A 23-year-old horse in Korea was diagnosed with Anaplasma bovis infection. • We used 16S rRNA gene sequencing and RFLP to identify the pathogen as A. bovis. • This is the first clinical report of A. bovis in horse, suggesting a new reservoir. A 23-year-old male Thoroughbred horse at the Korean Military Academy appeared thin with visible rib bones and presented clinical signs of fever, anorexia, lethargy, and severe dehydration. To determine the presence of various febrile disease-causing agents, the 23 cohabiting horses at the academy, including this horse, were subjected to hematology, blood chemistry, and molecular analysis using whole blood samples collected during regular medical check-ups. On the basis of clinical history, physical examination, hematology, blood chemistry, and fecal examination, differential diagnosis using molecular analyses was performed for various febrile disease-causing agents, including Lyme borreliae, Coxiella , piroplasms (Babesia and Theileria), Rickettsiales (Anaplasma , Ehrlichia , and Rickettsia), equine herpesvirus, equine infectious anemia virus, and equine arteritis virus. While other pathogens were not detected, PCR and phylogenetic analysis targeting the Anaplasma 16S rRNA gene revealed that the horse was infected with Anaplasma bovis. Although PCR targeting the groEL and gltA genes of A. bovis was not successful, the restriction enzyme fragment length polymorphism assay for differential diagnosis and determination of coinfectivity between Anaplasma phagocytophilum and A. bovis confirmed the pathogen as A. bovis. To the best of our knowledge, this is the first clinical report of A. bovis infection in a horse, suggesting a new reservoir host. [ABSTRACT FROM AUTHOR]

Trypanosoma equiperdum (T. equiperdum) causes dourine, a venereally transmitted infection in horses. Purification of semen by single layer centrifugation (SLC) has been proven to be successful in reducing venereally transmitted diseases when dealing with other pathogens. The objective of this study was to evaluate the purification of T. equiperdum spiked semen by SLC. Semen was spiked using cryopreserved T. equiperdum stabilates (Dodola strain isolate 943). In total, 6 concentrations, varying from 102 to >5 × 106 trypanosomes, were added to semen samples. Subsequently, SLC was performed following standard procedures. The presence of the parasite in the purified semen was checked by wet smear examination, ITS1 PCR and in vivo inoculation in mice. Before SLC, all spiked semen samples, except the negative controls, were positive on PCR analysis. After SLC, all the pellets were found to be negative for T. equiperdum on microscopic examinations. Examination of the pellet by PCR could also not detect any parasite-DNA in the SLC-pellet of semen spiked with the lower number of parasites (102 to104 trypanosomes). However, in the SLC pellets spiked with 104 - 5 × 104 trypanosomes, only 1 out of the 4 replicates was negative for parasite DNA. All groups spiked with >5 × 104 trypanosomes were found to be positive on PCR. All mice in the positive controls exhibited parasitaemia (5/5). Mice inoculated with SLC-purified semen that was spiked with lower than 5 × 104 trypanosomes, remained free of parasitaemia, similar to the negative controls. However inoculation with SLC-pellets from samples with a higher number of trypanosomes (>5 × 104 - 5 × 106 and > 5 × 106), induced parasitaemia in 2 out of 5 and 3 out of 5 mice, respectively. This study indicates that single layer centrifugation can be used to clear T. equiperdum infected semen but that the success is dependent on the number of parasites. Image 1 • Single layer centrifugation can be used to clear T. equiperdum infected semen. • The success to remove the parasite is dependent on the number of Trypanosomes. • A more persevering centrifugation protocol needed to remove the higher number of trypanosomes. [ABSTRACT FROM AUTHOR]

Halicephalobus gingivalis is a small saprophytic rhabditid nematode, represented only by females with a typical rhabditoid oesophagus and one egg in the uterus, capable of infecting vertebrates. This opportunistic parasite present in the soil, manure and decaying humus, is thought to penetrate through previous injuries to the mouth, eyes and skin of horses and migrate to various organs. The brain is one such organ, where the females lay their eggs, leading to malacia and causing a sudden onset of neurological signs, such as anorexia, ataxia, urinary incontinence, blindness, decreased menace and tonal reflexes, tremors and aggressiveness. The disease is invariably fatal whenever brain lesions are present, and the diagnosis usually achieved only post‐mortem. The present work aims to describe the first case of infection by H. gingivalis ever reported in Portugal. An 8‐year old warmblood horse presented with an 8‐day history of progressive blindness involving the left eye, initially with normal pupillary reflexes, advancing to bilateral blindness and increasing deterioration in clinical condition. After euthanasia, the animal was submitted for necropsy. Organ samples were collected and fixed in 10% neutral buffered formalin for routine histopathology. A large mass was found in the left kidney corresponding to fibrous tissue heavily infiltrated with inflammatory cells and numerous nematodes. In the brain, multiple, bilateral and asymmetrical foci of malacia containing several rhabditoid nematodes, larvae and zygotes, and high numbers of inflammatory cells were found. The nematodes were identified as H. gingivalis. The clinical history, necropsy and histological findings presented constitute a typical case of H. gingivalis infection in a horse, never previously described in Portugal to the authors' best knowledge. Humans can be infected by contact with contaminated manure, which makes this nematode a public health concern, especially for people living and/or working in close proximity to horses. [ABSTRACT FROM AUTHOR]

Although relatively uncommon in horses, infections caused by Mycobacterium spp. may affect the gastrointestinal tract. Mycobacterium branderi is a non-tuberculous Mycobacterium (NTM) that causes respiratory infections in man. Non-tuberculous mycobacteria may also affect horses; however, infection by M. branderi has not yet been reported in this species. This report describes the clinical, pathological, microbiological and molecular findings of M. branderi infection in a horse, causing granulomatous mesenteric lymphadenitis. A 17-year-old Thoroughbred stallion had a 3-month history of chronic diarrhoea, cachexia and ventral and cervical oedema. Necropsy examination revealed severe mesenteric lymphadenomegaly, together with mesenteric lymphangiectasia and diffuse small intestinal mucosal thickening. Microscopically, the mesenteric lymph node had diffuse granulomatous inflammatory infiltration, replacing most of the nodal parenchyma, with multiple acid-fast bacilli within the cytoplasm of macrophages. There was also diffuse lymphangiectasia. Fresh samples of mesenteric lymph nodes yielded no bacterial growth; however, nested polymerase chain reaction products obtained from the mesenteric lymph node samples were consistent with M. branderi. This infection should be included as a differential diagnosis in cases of chronic diarrhoea in horses, especially when granulomatous enteritis and lymphadenitis are also observed. [ABSTRACT FROM AUTHOR]

Currently, Canine influenza virus (CIV) H3N2 is continuously circulating in dog populations in China, Korea, and the United States (US). Both influenza SA‐α‐2,3‐Gal and SA‐α‐2,6‐Gal receptors have been observed in the respiratory tracts of both horses and dogs. Hence, the increasing number of CIV H3N2 cases in the world indicates a potential risk for transspecies transmission to horses with dog exposure. Here, a seroepidemiological survey of CIV H3N2 infections in horses was conducted using hemagglutination inhibition (HI), microneutralization (MN) and the chicken embryo neutralization test (CENT). From April 2014 to November 2016, 399 sera from race horses were collected in Guangzhou, Dongguan, Huizhou, and Shenzhen in China. Nine specimens (2.2%, 9/399) were positive for CIV H3N2 with HI titers ≥ 1:20, MN titers ≥ 1:80 and CENT titers ≥ 1:80. Furthermore, these positive horses showed significant correlation with dog exposure, and some dogs (20%, 3/15) from the same riding clubs as the positive horses also possessed antibodies against CIV H3N2. This study is the first to provide seroepidemiological evidence of CIV H3N2 infection in horses with exposure to dogs. Based on these findings, continuous serological and virological surveillance of CIV H3N2 infection among horses is imperative, and further animal experiments should be performed. [ABSTRACT FROM AUTHOR]

During July 2018, the first clinical case of neurological West Nile virus (WNV) infection was reported in a Belgian sports mare in Belgrade, Serbia. Typical symptoms, such as hypersensitive skin reaction, disorientation, weakness, ataxia and the loss of equilibrium were reported. Detection of WNV IgM antibodies by commercial ELISA in the serum samples of the diseased mare strongly indicated acute infection. The ELISA positive results were confirmed by VNT. Hematological and biochemical parameters were in the reference range. The only finding was a minor lymphopenia. WNV RNA was not detected by RT-qPCR in the blood sample extracted seven days after the disease had broken out. The horse improved clinically in two weeks while other horses at the same premises remained asymptomatic. The clinical, serological, biochemical and molecular analyses applied confirmed the first clinical case of neuroinvasive WNV infection in horses in Serbia. The West Nile virus has been circulating in Serbia in the last decade in mosquitoes, birds, and horses, but no evidence of equine WNV clinical cases were registered so far. [ABSTRACT FROM AUTHOR]

Summary: Limited scientific evidence from other countries and plenty of anecdotal evidence suggest that the risk of personal injury in equine veterinary practice is high. However, a comprehensive description of the types of risks to which equine veterinary surgeons expose themselves has not previously been available. The aim of this study was to quantify the number, types and causes of personal injury sustained by equine veterinary practitioners in the UK. An interview (and online) questionnaire‐based survey was conducted with a large number of equine veterinary practitioners. Questions were designed to identify the number of injuries sustained during the respondent's career to date and to acquire details of the worst injury sustained including cause, treatment and short‐ and long‐term outcomes. A total of 2292 injuries were reported by 620 respondents, equating to one injury every 3 years 7 months in those respondents. Most ‘worst’ injuries occurred while the veterinary surgeon was conducting most common reasons for equine examination. The most frequent sites of this ‘worst’ injury were the leg and the head with the main cause of injury being a kick with hindlimb. Of all reports, 33% of injuries resulted in a hospital admission of which 43% required hospital admission for longer than 24 h and 7% of reports resulted in a loss of consciousness. The main limitation of this work is the descriptive nature of the survey. It would be unwise to assume that the procedures identified as being most commonly associated with injury in the study are more risky than other less commonly conducted procedures. In conclusion, equine veterinary practice is a risky profession. Greater emphasis on and awareness of methods to avoid or mitigate risk should be a priority for anyone working with horses and their employers. [ABSTRACT FROM AUTHOR]

On the 15th of August 2016, a 6-month-old colt weighing 118 kg was presented to the large animal clinic of Veterinary Teaching Hospital, Michael Okpara University of Agriculture, Umudike. The colt showed clinical signs including fever, weakness, inappetence, anaemia, tachycardia, dyspnoea, rough hair coat, pale mucus membranes, lacrimation, ataxia and edematous swelling of distal limbs. Rhipicephalus eversti eversti ticks were detected on different parts of the colt's body. Examination of peripheral blood smear showed Babesia caballi within the erythrocytes. Haematological analysis showed a decrease in red blood cell count, packed cell volume and haemoglobin concentration. Administration of imidocarb dipropionate and good nursing care yielded a successful result after two weeks of treatment. It is necessary to control ticks by regular use of acaricide and timely treatment of affected horses in order to reduce the devastating effects of this protozoan disease. [ABSTRACT FROM AUTHOR]

Objective To identify prognostic variables for adult equids and foals with tetanus. Design Multicenter retrospective study (2000-2014). Setting Twenty Western, Northern, and Central European university teaching hospitals and private referral centers. Animals One hundred fifty-five adult equids and 21 foals with tetanus. Interventions None. Measurements and Main Results Variables from history and clinical examination were statistically compared between survivors and nonsurvivors (adults: 49 survivors, 85 nonsurvivors; foals: 7 survivors, 10 nonsurvivors). Cases euthanized for financial reasons were excluded. Mortality rates in adults and foals were 68.4% and 66.7%, respectively. Variables associated with survival in adults included: standing, normal intestinal sounds and defecation, voluntarily drinking, eating soft or normal food, lower heart and respiratory rates, high base excess on admission, longer diagnosis time, treatment and hospitalization delay, and mild severity grade. Variables associated with death included: anorexia, dysphagia, dyspnea, low blood potassium concentration on admission, moderate and severe disease grading, development of dysphagia, dyspnea, recumbency and seizures during hospitalization, treatment with glycerol guaiacolate, intravenous fluids, and intravenous glucose solutions. Variables associated with survival in foals included standing on admission, voluntarily eating soft food and drinking, older age, and longer hospitalization delay. Outcome was not different between different tetanus antitoxin (TAT) dosages, although there was a trend of increasing survival rate with increasing TAT dosages. Cases with appropriate vaccination prior to development of tetanus were rare, but had improved outcome and shorter hospitalization. Conclusions Prognosis for equine tetanus is poor with similar outcome and prognostic factors in foals and adults. The prognostic assessment of cases with tetanus provides clinicians with new evidence-based information related to patient management. Several prognostic indicators relate to the ability to eat or drink, and more severe clinical signs relate to poor outcome. Increasing intravenous dosages of TAT has no significant effect on outcome, but the positive trend identified may support a recommendation for high intravenous TAT dosages. Further evaluation is warranted. [ABSTRACT FROM AUTHOR]

Objective To describe clinical data of hospitalized adult equids and foals with tetanus. Design Multicenter retrospective study (2000-2014). Setting Twenty Western, Northern, and Central European university teaching hospitals and private referral centers. Animals One hundred fifty-five adult equids (>6 months) and 21 foals (<6 months) with tetanus. Interventions None. Measurements and Main Results Information on geographic, annual and seasonal data, demographic- and management-related data, clinical history, clinical examination and blood analysis on admission, complications, treatments, and outcomes were described and statistically compared between adults and foals. The described cases were often young horses. In 4 adult horses, tetanus developed despite appropriate vaccination and in 2 foals despite preventive tetanus antitoxin administration at birth. Castration, hoof abscesses, and wounds were the most common entry sites for adults; umbilical cord infections and wounds for foals. Stiffness was the commonest observed initial clinical sign. Blood analyses frequently revealed an inflammatory response, hemoconcentration, muscle damage, azotemia, negative energy balance, liver damage, and electrolyte and acid base disturbances. Common complications or clinical signs developing during hospitalization included dysphagia, dyspnea, recumbency, hyperthermia, seizures, hyperlipemia, gastrointestinal impactions, dysuria, and laryngeal spasms. Cases were supported with wound debridement, antimicrobial treatment, tetanus antitoxin, muscle spasm and seizure control, analgesia, anti-inflammatory drugs, fluid therapy, and nutritional support. Mortality rates were 68.4% in adult horses and 66.7% in foals. Foals differed from adult horses with respect to months of occurrence, signalment, management-related data, potential causative events, clinical signs on admission, blood analysis, complications, and severity grades. Conclusions This is the first study that rigorously describes a large population of equids affected by tetanus. The information provided is potentially useful to clinicians for early recognition and case management of tetanus in adult horses and foals. Tetanus affects multiple organ systems, requiring broad supportive and intensive care. Neonatal and adult tetanus in the horse should be considered as distinct syndromes, as in human medicine. [ABSTRACT FROM AUTHOR]

Pteropid bats (flying-foxes) are the natural reservoir of Hendra virus, an emergent paramyxovirus responsible for fatal infection in horses and humans in Australia. Pteropus alecto (the Black flying-fox) and the paraphyletic P. conspicillatus (the Spectacled flying-fox) appear to be the primary reservoir hosts. Previous studies have suggested that physiological and ecological factors may underpin infection dynamics in flying-foxes, and subsequent spillover to horses and in turn humans. We sought to examine temporal trends in urinary cortisol concentration in wild Australian flying-fox populations, to elucidate the putative relationship between Hendra virus infection and physiological stress. Pooled and individual urine samples were non-invasively collected from under roosting flying-foxes at two latitudinally disparate regions in the eastern Australian state of Queensland. Hendra virus detection, and (in individual urine samples) sex and species determination were PCR-based. Urinary cortisol measurement used a validated enzyme immunoassay. We found no direct correlation between increased urinary cortisol and Hendra virus excretion, but our findings do suggest a biologically plausible association between low winter temperatures and elevated cortisol levels in P. alecto in the lower latitude Southeast Queensland roosts. We hypothesize an indirect association between low winter temperatures and increased Hendra virus infection and excretion, mediated by the physiological cost of thermoregulation. Our findings and our approach are directly relevant to elaboration of the disease ecology of Nipah virus and other emerging henipaviruses in bats. More broadly, they inform investigation of emerging disease infection dynamics across the wildlife/livestock/human interface. [ABSTRACT FROM AUTHOR]

African horse sickness (AHS) is a fatal disease of equids relevant to the global equine industry. Detection of AHS virus (AHSV) during outbreaks has become more rapid and efficient with the advent of group specific reverse transcriptase quantitative polymerase chain reaction (GS RT-qPCR) assays to detect AHSV nucleic acid. Use of GS RT-qPCR together with recently described type specific (TS RT-qPCR) assays cannot only expedite diagnosis of AHS but also facilitate further evaluation of the dynamics of AHSV infection in the equine host. A potential limitation to the application of these assays is that they detect viral nucleic acid originating from any AHS live attenuated vaccine (LAV), which is the vaccine type routinely administered to horses in South Africa. The aim of this study was to contrast the dynamics and duration of the RNAaemia to the serological responses of horses following immunization with a commercial polyvalent AHSV-LAV using GS and TS RT-qPCR assays and serum neutralisation tests. The results of the study showed extended RNAemia in vaccinated horses, and that more horses tested positive on GS RT-qPCR with lower Cq values after receiving the AHSV-LAV containing types 1, 3 and 4 prior to the vaccine containing types 2, 6, 7 and 8, rather than when the vaccine combinations were reversed. Furthermore, lower Cq values were obtained when vaccines were administered 4 weeks apart as compared with a longer interval or 12 weeks apart. These findings are of particular relevance in regions where AHSV-LAVs are used as the use of these vaccines may complicate the accurate interpretation of diagnostic testing results. [ABSTRACT FROM AUTHOR]

The aim of the current study was to determine the prevalence of Theileria equi and Babesia caballi infections in horses in the Central and Southwest, Iran. Blood samples were collected from 53 and 37 horses settled in Isfahan and Shahrekord, respectively and a PCR method was used to detect the parasites in blood samples. The results showed that Theileria equi detected in 6 horses in Isfahan and in 4 horses in Shahrekord. Based on the findings, the prevalence of equine theileriosis was much higher than babesiosis and it occurred in both Isfahan and Shahrekord regions of the country. To the authors’ knowledge, this is the first report of the molecular survey of Theileria equi and Babesia caballi infections in horses in Iran. This survey could provide further information on different parasitic infections in horses and its epidemiology. [ABSTRACT FROM AUTHOR]

This study aimed to monitor the occurrence of gastrointestinal parasites in horses evaluating different rural properties in Santa Catarina State, Southern Brazil. Fresh samples of feces were collected and processed by the McMaster technique, quantifying the number of eggs per gram of feces (EPG), followed by coproculture for identification of helminths. The population investigated was composed of 111 horses of varying ages (1-27 years, 63 males and 48 females). Among all the animals evaluated, 76 animals showed EPG ≥50, representing 63.96 % (IC 54.24-72.70) of samples positive for gastrointestinal helminths. The EPG values ranged from 0 to 5600, with EPG average set as 490. There was a great variation among EPG in different farms. The anthelmintic treatments were carried out in all properties, most of them ranging from 30 to 90 or more 90 days. However, when we correlated the interval of treatment with EPG values, we did not observe significant difference for these variables ( P > 0.05). Similarly, there was also no relation between EPG with age and sex of horses ( P > 0.05), showing that the EPG values are not dependent of these two independent variables. In coproculture, 40 % of the evaluated properties had only the presence of Strongylus spp., while 60 % had mixed infection of Strongylus sp. and Trichostrongylus sp. With our results, we conclude that approximately 64 % of the horses of this study were positive for gastrointestinal parasites. [ABSTRACT FROM AUTHOR]

West Nile virus (WNV) is an important arthropod-borne pathogen and a leading cause of morbidity and mortality in human and animal populations in many parts of the world. The presence of WNV in Turkey has been reported in various studies during the last 15 years. In this study, 1500 horse serum samples collected from Ardahan Province in Northeastern Turkey were screened by using a virus neutralization test against WNV and then positives were confirmed by a plaque reduction test-90 (PRNT90). The overall seropositivity was 0.13% (2/1500), with neutralizing antibody titers determined to be 1/40 and 1/80. These findings suggest that some of horses in Ardahan had been exposed to WNV and also indicates the evidence of WNV circulation in the Northeastern Turkey. [ABSTRACT FROM AUTHOR]

Parasitic gastroenteritis (PGE) caused by infection of the gut with parasitic nematodes is one of the most important diseases of livestock animals from both financial and welfare perspectives. Parascaris equorum and Habronema microstoma are of the most endemic nematodes of the world which are currently the major cause of PGE of the domestic horses in Egypt. The present investigation introduced the first morphological description of these nematodes recovered from the domestic horse, Equus ferus caballus (Equidae), in Egypt by light and scanning electron microscopy. Seven P. equorum (fifth stage) and 18 adults of H. microstoma were recovered from the gastrointestinal tracts of four young domestic horses collected during the year of 2015. Microscopic examination of the isolated fifth stage P. equorum revealed that it possessed a long body with a broad anterior end equipped by large shamrock-like lips with deep transverse groove on medial surface set off from the rest of the body by a deep post-labial constriction giving the body a shouldered appearance. The total body length was 12-15 (14 ± 2) cm for males and 13-18 (16 ± 2) cm for females. Lips were three in number in the form of one dorsal and two sub-ventral surrounding the central stoma. The isolated adult worms of H. microstoma were whitish in color narrowed slightly at the anterior end. Single lateral ala in the cephalic region in both sexes was observed. The buccal vestibule was markedly thickened and equipped by two tridentate teeth. The adult worms had two bilobed lateral lips surrounding the mouth with four sub-median cephalic papillae and two amphids. The males were 14.5-18.0 (17.2 ± 0.3) mm long and 1.23-1.57 (1.42 ± 0.3) mm wide. The posterior end was spirally coiled and had wide caudal alae. The spicules were unequal. The females were 13.5-21.0 (16.2 ± 0.3) mm long and 1.55-1.75 (1.69 ± 0.3) mm wide. The anal pore had a thin upper rim and was located 177.0 μm from the posterior end. [ABSTRACT FROM AUTHOR]

This paper summarises the clinical findings of 9 cases of disseminated alimentary mycobacteriosis in horses presented at a Finnish referral equine hospital 2009-2014. Four of 9 horses were Standardbreds and 8/9 horses were male. The median age was 2 years, ranging from 6 months to 15 years. The duration of clinical signs before admission ranged from 2 weeks to 6 months. All horses demonstrated deterioration of the clinical signs after a protracted period of the disease and were finally subjected to euthanasia after poor response to multiple medical therapies. The most common complaints on admission were weight loss and diarrhoea (9/9), pyrexia (7/9), ventral oedema (7/9), lethargy (7/9) and inappetance (6/9). The most common clinicopathological abnormalities were hypoalbuminaemia and hyperfibrinogenaemia, which were present in all horses. Rectal biopsy specimens were examined from 5/9 horses and specimens were stained with Ziehl-Nielsen ( ZN). At rectal biopsy, mild multifocal neutrophilic or mild granulomatous proctitis was recognised in all 5 horses, but the ZN stain for mycobacteria was positive in only one biopsy. A liver biopsy was taken from one horse in which hepatomegaly was observed clinically and revealed marked granulomatous hepatitis with the presence of mycobacteria. The rectal biopsy from this horse was ZN negative. At post mortem examination, chronic, multifocal to coalescing granulomatous typhlocolitis and lymphadenitis were found in all horses with the small intestine less frequently involved. At histopathological examination of post mortem samples, a ZN stain was performed and intracellular acid-fast bacilli were identified in macrophages and multinucleated giant cells in the large intestine, liver and lymph nodes in 9/9 horses and in the small intestine in 5/9 horses. Mycobacterium avium ssp. hominissuis was isolated in 5/9 horses from post mortem samples. [ABSTRACT FROM AUTHOR]

Rupture of the urinary bladder is rare in adult horses with various standing or recumbent surgical repair techniques historically reported as the treatments of choice. This case series describes the successful conservative management of cystorrhexis in 4 adult horses. Conservative management is therefore a potentially viable treatment option which forgoes the risks of general anaesthesia and may reduce the post operative complications associated with surgery of the bladder. [ABSTRACT FROM AUTHOR]

Six young horses presented with clinical signs of maxillary cheek teeth apical infection (bilateral in 2 horses) that included the presence of rostral maxillary swellings with discharging sinus tracts and were unexpectedly found to have no evidence of endodontic infection in 7 affected teeth. The apical infection of these teeth was attributed to infundibular dysplasia that allowed inoculation of the periapical tissue with contaminated oral contents. Treatment was by debridement and obturation of affected infundibula from their occlusal aspect using techniques normally used for endodontic therapy. Five out of 6 cases showed resolution of clinical signs over a mean follow-up period of 19 months (range 6-48 months). These cases demonstrate that patency of the infundibular apex is a potential cause of cheek teeth apical infection in young horses, which can be successfully treated by debridement and subsequent infundibular restoration. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the concentrations of oxidative stress parameters and DNA damage in horses infected by Theileria equi . Initial screening of 110 horses with duplex PCR enabled the selection of 30 infected horses with T. equi and 30 free of infection (control). Specimens from the 60 horses were further analysed by determining the following oxidative stress parameters: extent of haemolysis (EH), plasma free haemoglobin (PHb), catalase (CAT), Cu,Zn superoxide dismutase (SOD1), paraoxonase (PON1), nitrite (NO 2 − ), total nitrate and nitrite (NOx), malondialdehyde (MDA) and free thiol groups (–SH). In addition, relative distribution of lactate dehydrogenase (LDH 1 –LDH 5 ) activity and the DNA-damaging effects of T. equi infection were evaluated. Compared to control horses, horses infected with T. equi had significantly higher SOD1 activities ( P  <   0.05) and PHb ( P  <   0.01), NO 2 − ( P  <   0.001), NOx ( P  <   0.05) and MDA concentrations ( P  <   0.001), and significantly lower EH ( P  <   0.001), CAT ( P  <   0.01) and PON1 ( P  <   0.001) activities, and thiol group concentrations ( P  <   0.05). The comet assay demonstrated significantly increased DNA damage in T. equi infected cells compared to non-infected cells ( P  <   0.001). Infected horses had significantly increased LDH 5 isoenzyme activities ( P  <   0.05). There was higher production of ROS/RNS in T. equi- infected horses, which resulted in changes in osmotic fragility, damage to lipids, proteins and DNA, haemolysis and hepatocellular damage. Oxidative stress in horses naturally infected with T. equi could contribute to the pathogenesis of the infection. [ABSTRACT FROM AUTHOR]

Despite recent developments in advanced imaging, radiography remains the most commonly employed imaging modality for investigating apical infection of cheek teeth in horses. Radiographic technique, knowledge of the normal anatomy and horse compliance are paramount for acquiring good quality dental radiographs. Interpretation of subtle pathology can be difficult for even the most experienced radiologist; however, in more chronic cases, identification of dental abnormalities is easier. [ABSTRACT FROM AUTHOR]

Hendra virus (HeV) is an important emergent virus in Australia known to infect horses and humans in certain regions of the east coast. Whilst pteropid bats (“flying foxes”) are considered the natural reservoir of HeV, which of the four mainland species is the principal reservoir has been a source of ongoing debate, particularly as shared roosting is common. To help resolve this, we sampled a colony consisting of just one of these species, the grey-headed flying fox, (Pteropus poliocephalus), at the southernmost extent of its range. Using the pooled urine sampling technique at approximately weekly intervals over a two year period, we determined the prevalence of HeV and related paramyxoviruses using a novel multiplex (Luminex) platform. Whilst all the pooled urine samples were negative for HeV nucleic acid, we successfully identified four other paramyxoviruses, including Cedar virus; a henipavirus closely related to HeV. Collection of serum from individually caught bats from the colony showed that antibodies to HeV, as estimated by a serological Luminex assay, were present in between 14.6% and 44.5% of animals. The wide range of the estimate reflects uncertainties in interpreting intermediate results. Interpreting the study in the context of HeV studies from states to the north, we add support for an arising consensus that it is the black flying fox and not the grey-headed flying fox that is the principal source of HeV in spillover events to horses. [ABSTRACT FROM AUTHOR]

A Methicillin-resistant Staphylococcus aureus (MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare's stable and at the Veterinary Hospital, where the mare was operated/hospitalized, and screened for the presence of MRSA that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phenotypic and genetic multidrug resistance patterns and macrorestriction-pulsed-field gel electrophoresis profiles. The only MRSA detected from humans was a CC1, ST1-t127-SCCmec-IVa. This paper represents the first report of a clinical MRSA infection in a horse in Italy. This study also supports the opinion that improper use of antibiotics and hospitalization/surgery can represent risk factors for MRSA colonization/infection in horses, and that the environment is among important sources for exposure. [ABSTRACT FROM AUTHOR]

Since 2012, three viruses, known as equine hepacivirus (EqHV), equine pegivirus (EPgV) and Theiler’s disease-associated virus (TDAV), have been discovered in equines. Given that these viruses are the newest members of the Flaviviridae family, genomic information concerning circulating EqHV, EPgV and TDAV strains around the world is limited. To date, no genetic surveillance studies have been performed on these three viruses in the equine population of China. Here, a total of 177 serum samples were collected from equines across China between 2014 and 2015. Using PCR, we detected viral RNA in the serum samples, six of which were EqHV positive and two of which were EPgV positive. Co-infection with the two viruses was not observed among the Chinese equines studied, and TDAV RNA was not detected in the equine serum samples collected for this study. Phylogenetic analysis of partial NS5B open reading frame (ORF), NS3 ORF, and 5’ untranslated region nucleotide sequences from EqHV as well as partial NS3 ORF sequence from EPgV indicated that EqHV and EPgV have evolved into two main clades by themselves, both of which are circulating in China. Based on the partial NS5B and NS3 ORF sequences of EqHV, the sequences of one clade were also split into two subclades. This study enriches our knowledge of the geographic distribution of these three equine viruses. [ABSTRACT FROM AUTHOR]

Cyathostomins are the most prevalent horse nematodes worldwide and over 50 species are described. The eggs and the infective larvae (L3) can easily be obtained or cultured from infected horses, but cannot be differentiated morphologically at species level. A reverse line blot (RLB) method based on the hybridization of a PCR fragment with a species specific probe, has previously been developed for the differentiation of individual eggs and/or L3s, but is too labor intensive for large scale studies. In the present study a RLB method on multiple pooled L3s for the semi-quantitative differentiation of cyathostomin larval cultures was developed and validated. First, the probability of the presence of a certain species within a pool was calculated as function of the frequency and the number of L3s within a pool. Ten L3s per pool were found to be optimal. Next, the probability, the chance of occurrence was calculated when 4 pools per culture were used. The probability distributions for 0, 1, 2, 3 or 4 positive pools were transformed into the corresponding median frequency of the cumulative probability: 0.014, 0.04, 0.08, 0.16 and 0.59, respectively. Based on these calculated probabilities, RLB on 10 L3s per pool and 4 pools per sample was validated by estimating the cross-hybridization, precision and accuracy in 3 groups of horses. First, absence of cross-hybridization was confirmed by differentiation of the same L3s (160 L3s from the 4 horses from group 1) in the RLB on individual as well as on pooled L3s. Cross-hybridization was excluded for 9 of the most common cyathostomins. Next, the precision and accuracy were determined by the differentiation of 10 replicates of 3 cultures from 3 horses from group 2 (1200 L3s). The coefficient of variation (CV) was between 0 and 0.90 and the accuracy was between 0.42 and 1.73. A Monte Carlo simulation based on the observed scores and associated probability distributions gave similar results as the use of a fixed median frequency. The LPGs obtained from 276 larval culture counts from a larger cohort (23 horses, group 3) were not significantly different from the LPGs obtained from summation of the LPG per species found by RLB on pooled L3s. The RLB on pooled L3s was found therefore an useful semi-quantitative method for the differentiation of the most common cyathostomin L3, with a workload of approximately one tenth of that of the RLB on individual L3s. [ABSTRACT FROM AUTHOR]

This paper describes cultivation methods for ciliates from the digestive tract of horses. Members of three different genera were successfully grown in vitro for short periods of time. However, only cells belonging to the genus Blepharocorys, which resides in the horse's large intestine, were maintained for longer periods. This Blepharocorys culture was successfully grown in vitro after inoculation of freshly excreted horse faeces in culture medium containing a population of bacteria. The ciliates survived for over six months, and the density of their population varied between 1.7 × 103 and 2.4 × 103 cells mL-1. Favourable conditions for the prolonged cultivation of this ciliate were observed when the medium was prepared by mixing horse faeces and 'caudatum' salt solution in a 1:1 V/V ratio together with food (60% powdered meadow hay, 16% wheat gluten, 12% barley flour and 12% microcrystalline cellulose) supplied as 0.20 mg mL-1 culture per day. [ABSTRACT FROM AUTHOR]

Cyathostomins are currently the most common internal parasites of horses. With the intensive use of anthelmintic drugs over the past decades, resistance of cyathostomins to anthelmintics is becoming a growing problem in many countries. The aim of this study was to assess the current situation on horse farms in the German federal state of Brandenburg. A pre-selected population of horses from 24 premises that had shown a prevalence of cyathostomins higher than the average in a previous study was examined for anthelmintic efficacy. Faecal egg count reduction tests (FECRTs) were performed for ivermectin (IVM) and pyrantel (PYR). For IVM, the egg reappearance period (ERP) was also examined, as a shortened ERP can be indicative of developing resistance. The efficacy of IVM on cyathostomins was high: 99.1 % of 224 horses had a zero egg count 14 days after treatment. No shortening of the ERP was detected. For the data of the FECRT for PYR, three different methods of calculation were employed: (a) the method as recommended by the World Association for the Advancement of Veterinary Parasitology (WAAVP), (b) a bootstrapping method and (c) a Markov chain Monte Carlo method. Two methods of interpretation for these data were used: Resistance was declared (a) when FECR was <90 % and the lower 95 % confidence interval (LCL) <80 % and (b) when additionally the upper 95 % confidence level (UCL) was <95 %. When applying the first interpretation, resistance against PYR was found on four yards, while, when considering the UCL, all three methods for calculation only detected resistance on one single yard. Twelve species of cyathostomins were detected in larval cultures derived from strongyle egg positive faecal samples collected 14 days after treatment with PYR by reverse line blot hybridization (RLB). In order to generate comparable data, it is suggested to establish international standards for the calculation of FECRT data. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the occurrence of Toxoplasma gondii among horses and its associated risk factors in Alagoas, Brazil. In total, 440 samples from 36 properties in 23 districts of the state of Alagoas were studied, covering the Leste, Agreste and Sertão mesoregions. Risk factors were evaluated through the application of an investigative questionnaire that focused on the productive, reproductive and sanitary management of herds. T. gondii infection were assayed using the immunofluorescence assay (IFA) with a cutoff point of 64; 14.4% (95% CI: 11.0%-17.8%) of--horses were seropositive. A significant association was determined between anti-T. gondii antibody presence and the consumption and storage of hay (OR = 2.08/95% CI: 1.20-3.62). This is the first report of T. gondii infection among horses in the state of Alagoas, Brazil. [ABSTRACT FROM AUTHOR]

Summary: Mycobacterial infections in equids are relatively rare but the case report (Charlesworth 2017) detailed in this issue highlights that Mycobacterium bovis infections may still result in clinical signs in this incidental host and have zoonotic potential. Most reported cases of M. bovis in horses have a protracted disease course, with features including pyrexia, weight loss and oedema with a nonspecific inflammatory profile. As such, the clinical features of disease overlap with conditions such as neoplasia, peritonitis, protein‐losing enteropathies and bacterial infections including Rhodococcus equi and Lawsonia intracellularis. In this clinical satellite article, mycobacterial infections in equids are considered in terms of incidence and mode of transmission, key clinical features and perhaps most importantly, in terms of the diagnostic techniques that can be used in order to reach a definitive (ante mortem) diagnosis. The major zoonotic risk to veterinary personnel is likely to occur at the time of post‐mortem examination of infected horses, and awareness of these potential risks remains of the utmost importance. [ABSTRACT FROM AUTHOR]

Problem addressed Streptococcus zooepidemicus (Sz) and its clonal derivative Streptococcus equi (Se) share greater than 96% DNA identity and elicit immune responses to many shared proteins. Identification of proteins uniquely targeted by the immune response to each infection would have diagnostic value. Objective The aim of the study was to compare serum antibody responses of horses infected by Se or Sz. Methods and approach Antibody levels were measured to panels of recombinant proteins of Sz and Se in sera of horses and ponies before and after experimental and naturally occurring invasive infections by these organisms. Antibody responses to an Se extract vaccine were also measured. Sera diluted 1:200 were assayed in triplicate using optimum concentrations of 9 and 14 immunoreactive proteins of Se and Sz, respectively. Bound IgG was detected using HRP-Protein G conjugate. Results Antibodies specific for SeM-N2, IdeE2, Se42.0 and Se75.3 (SEQ2190) were elicited by Se but not by Sz infection. Commercial Se extract vaccine did not elicit responses to IdeE2 or Se75.3. Sz infections resulted in significant ( p < 0.01) responses to Sz115, SzM, ScpC, SzP, MAP and streptokinase an indication these proteins are expressed during opportunistic invasions of the respiratory tract. FSR and HylC specific responses were unique to infections by Sz. Conclusions The data indicate antibodies to IdeE2, Se75.3 and SeM-N2 may be used to distinguish infection by Se from that caused by the closely related Sz. Se infection, but not vaccination with Se extract elicits antibody to IdeE2 and Se75.3. [ABSTRACT FROM AUTHOR]

Objective--To evaluate predictor variables for and complications associated with Streptococcus equi subsp equi infection (strangles) in horses. Design--Retrospective case-control study. Animals--108 horses with strangles (cases) and 215 horses without strangles (controls). Procedures--Medical records from January 2005 through July 2012 were reviewed. Cases were defined as horses with clinical signs of strangles (pyrexia, retropharyngeal lymphadenopathy, and mucopurulent nasal discharge) that were associated with a confirmed strangles outbreak or had positive results for S equi on PCR assay or bacteriologic culture. Controls were defined as horses with pyrexia that did not meet the other criteria for cases. Data compared between cases and controls included signalment, clinical signs, diagnostic test results, and disease complications and outcome. Logistic regression was used to identify variables associated with strangles and its complications. Results--Clinical signs of strangles were not evident in 12 of 25 cases classified as S equi carriers (infected > 40 days). Predictor variables associated with strangles included mucopurulent nasal discharge and external abscesses in the pharyngeal region. Strangles was more likely to be diagnosed in the spring than in the summer. Cases with anemia were more likely to develop purpura hemorrhagica than were cases without anemia. No risk factors were identified for the development of guttural pouch empyema or metastatic abscesses. Conclusions and Clinical Relevance--Results indicated that not all horses infected with S equi develop clinical signs of strangles. We recommend that guttural pouch endoscopy and lavage with PCR assay of lavage fluid samples be performed to identify S equi carrier horses. [ABSTRACT FROM AUTHOR]

Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies. [ABSTRACT FROM AUTHOR]

Nine ponies were experimentally infected with third stage cyathostome larvae. These animals were examined post-mortem for small strongyle infections from October 2011 to January 2012. Seventeen species of the following Cyathostominae genera were identified: Coronocyclus, Cyathostomum, Cylicocyclus, Cylicostephanus, Gyalocephalus and Petrovinema. Of the 17 species of Cyathostominae recovered, Cyathostomum catinatum, Cyathostomum alveatum and Cylicocyclus nassatus were the most prevalent (100 %). From the entire population of Cyathostominae, 65.6 % were located in the caecum and only 34.4 % in the colon. Only 1,736 (24,6 %) females and 5,329 (75,4 %) males were observed. There was a significant difference between the number of males and females in the genus Cyathostomum, Cylicocyclus and Gyalocephalus. [ABSTRACT FROM AUTHOR]

A sizeable Indian equine population is considered to be pre-immune carrier of Theileria equi infection. In this study we confirmed the presence of T. equi specific DNA in Hyalomma anatolicum ticks which were infested on sero-positive horses. Fifty two Indigenous horses were randomly selected from endemic areas and their blood and tick samples were collected. Tick salivary glands and blood samples were processed for separation of DNA and serum, respectively. Serum samples were analyzed by EMA-2ELISA and nine horses were found positive for T. equi specific antibodies. Species-specific primers were designed from EMA-2 gene of T. equi, so as to amplify 398 bp fragment in PCR. The gene fragment was amplified in PCR on the DNA samples (from blood) from these nine sero-positive horses. Corresponding six tick's DNA samples collected from these nine seropositive animals were observed positive in PCR. Further, qPCR assay demonstrated presence of T. equi DNA in infected tick's salivary glands, which was also confirmed by microscopic examination of infected acinar. This study concluded that Hyalomma anatolicum ticks infested on T. equi seropositive horses have sporozoite developmental stage in their salivary glands, which is an evidence for transmitting potential of these tick among Indian horse population. [ABSTRACT FROM AUTHOR]

We report a case of an outbreak of inflammatory dermatophytoses caused by Arthroderma vanbreuseghemii (formally Trichophyton mentagrophytes pro parte) that involved an infected horse, the owner and at least 20 students, staff and stablemen at a veterinary school in Bern (Switzerland) that presented highly inflammatory dermatitis of the body and the face. Transmission from human to human was also recorded as one patient was the partner of an infected person. Both the phenotypic characteristics and ITS sequence of the dermatophytes isolated from the horse and patients were identical, consistent with the conclusion that the fungus originated from the horse. Three infected persons had not been in direct contact with the horse. Although direct transmission from human to human cannot be ruled out, fomites were most likely the source of infection for these three patients. Inspection of the literature at the end of the nineteenth and beginning of the twentieth century revealed that this dermatophyte was frequently transmitted from horses to humans in contact with horses (stablemen, coachmen, carters and artillery soldiers). The rarity of the present case report at the present time is likely related to the transformation of civilisation from the nineteenth century to nowadays in Europe with the change of horse husbandry. In addition, the inadequate immune response of the horse and the high number of people in contact with it at the equine clinic may explain the exceptional aspect of this case report. [ABSTRACT FROM AUTHOR]

Interleukin-3 is a growth and differentiation factor for various hematopoietic cells. IL-3 also enhances stimulus-dependent release of mediators and cytokine production by mature basophils. Function of IL-3 has not been studied in horses because of lack of horse-specific reagents. Our aim was to produce recombinant equine IL-3 and test its effect on sulfidoleukotriene and cytokine production by equine peripheral blood leukocytes (PBL). Equine IL-3 was cloned, expressed in E. coli and purified. PBL of 19 healthy and 20 insect bite hypersensitivity (IBH)-affected horses were stimulated with Culicoides nubeculosus extract with or without IL-3. Sulfidoleukotriene (sLT) production was measured in supernatants by ELISA and mRNA expression of IL-4, IL-13 and thymic stromal lymphopoietin (TSLP) assessed in cell lysate by quantitative real-time PCR. Recombinant equine IL-3 (req-IL-3) had a dose dependent effect on sLT production by stimulated equine PBL and significantly increased IL-4, IL-13 and TSLP expression compared to non-primed cells. IL-3 priming significantly increased Culicoides -induced sLT production in IBH-affected but not in non-affected horses and was particularly effective in young IBH-affected horses (≤3 years). A functionally active recombinant equine IL-3 has been produced which will be useful for future immunological studies in horses. It will also allow improving the sensitivity of cellular in vitro tests for allergy diagnosis in horses. [ABSTRACT FROM AUTHOR]

For this study, 724 gastrointestinal tracts of slaughter horses were investigated to determine the prevalence, intensity of Anoplocephala perfoliata and tapeworm development stages over the second, third and fourth quarter of 2012 and the first quarter of 2013. For each positive horse, faecal samples were collected from the rectum or small colon for coproscopic examinations. The samples were analysed using dedicated modified sedimentation-flotation methods. In total, 52 horses were infected with A. perfoliata in the course of the study, with an overall prevalence of 7.2 %. The prevalence changed over the study period; however, not markedly. The overall mean of A. perfoliata abundance was 12.3 (3.23) and did not differ significantly between the quarters. Mean invasion intensity did not differ significantly between the quarters. The quantity of mature tapeworms did not differ significantly over the study period; however, there was a significant difference in the number of immature tapeworms. The highest number of mature tapeworms was found in the first quarter of 2013. The number of detected tapeworm eggs rose significantly over the study period. The total number of tapeworms did not have a significant influence on the presence/absence of detected eggs. However, there was a noticeable difference between the number of mature tapeworms and presence/absence of eggs in faeces. This clearly indicates that the efficacy of the modified sedimentation-flotation method is influenced by seasonality, and therefore the most effective and reliable time for detection of A. perfoliata in equines is the first quarter of the year. [ABSTRACT FROM AUTHOR]

In the horse, Lawsonia intracellularis infection results in equine proliferative enteropathy (EPE). While upwards of 100% of weanlings on an endemic farm may seroconvert, only a small percentage (approximately 5%) will develop clinical disease. Cell-mediated immune mechanisms likely play a role in resistance to L. intracellularis and the absence of a L. intracellularis -specific IFN-γ response has been associated with the development of EPE. The goal of this study was to determine whether protection from clinical EPE is associated with the induction of a systemic IgG sub-isotypic response consistent with a Th1-type cytokine response. To describe their L. intracellularis /EPE status, horses enrolled in this study were placed into one of three categories: seropositive-only, vaccinated, and presumptive clinical EPE. An existing ELISA method was modified to detect L. intracellularis -specific IgG(a), IgG(b), and IgG(t) antibodies using the mouse anti-equine hybridomas CVS-48, CVS-39, and CVS-40, respectively. Additionally, the existing ELISA method was used to quantify total IgG antibodies specific for L. intracellularis for comparison between the groups. Total L. intracellularis -specific IgG was found to be significantly higher ( p < 0.05) in presumptive clinical EPE cases ( n = 21) when compared with seropositive (exposed but unaffected) ( n = 36) and vaccinated horses ( n = 27). Further, a similar pattern for IgG(a) was seen in that the presumptive clinical EPE horses had significantly more L. intracellularis -specific IgG(a) ( p < 0.05) than the seropositive or vaccinated horses. With IgG(b), however, the vaccinated horses had significantly more IgG(b) ( p < 0.05) than the presumptive clinical or seropositive horses. No L. intracellularis -specific IgG(t) was detected in samples from any of the groups. While the results presented here with respect to IgG(a) response in the presumptive clinical EPE group were expected, a higher concentration of IgG(a) was anticipated in the seropositive horses that failed to develop clinical disease as well as in the vaccinated horses. Future work utilizing newer reagents against a broader range of equine IgG sub-isotypes may provide additional information once these become commercially available. [ABSTRACT FROM AUTHOR]

The current article describes outbreaks of vesicular stomatitis (VS) in horses and cattle in Paraiba and Rio Grande do Norte states, northeastern Brazil, between June and August 2013. The reported cases affected 15–20 horses and 6 cattle distributed over 6 small farms in 4 municipalities, but additional data indicated the involvement of a large number of animals on several farms. The disease was characterized by blisters; eruptive lesions in coronary bands, lips, mouth, and muzzle; salivation; claudication and loss of condition. Swollen lower limbs and lips, and ulcerated and erosive areas in the lips and muzzle were observed in some horses. A necrotizing vesiculopustular dermatitis and stomatitis was observed histologically. Vesicular stomatitis virus was isolated from the vesicular fluid of a horse lesion and shown to be serologically related to the VS Indiana serogroup (VSIV) by virus neutralization. Convalescent sera of affected horses and cattle, and from healthy contacts, harbored high levels of neutralizing antibodies against the isolated virus (named VSIV-3 2013SaoBento/ParaibaE). Genomic sequences of VSIV subtype 3 (Vesicular stomatitis Alagoas virus) were amplified by reverse transcription polymerase chain reaction out of clinical specimens from a cow and a horse from different farms. Nucleotide sequencing and phylogenetic analysis of the phosphoprotein gene indicated that the 2 isolates were derived from the same virus and clustered them in VSIV-3, along with VS viruses identified in southeastern and northeastern Brazil in the last decades. Thus, the present report demonstrates the circulation of VSIV-3 in northeastern Brazil and urges for more effective diagnosis and surveillance. [ABSTRACT FROM PUBLISHER]

The objective of this study was to identify selected blood immunological and biochemical parameters in horses infected with Cyathostominae before and after treatment with ivermectin. Fecal samples were collected before ivermectin treatment and on days 1, 2, 3, 4, 10, 20, 30, 40, 50, 60, and 75 after drug administration. Blood was sampled on the same days to determine levels of total protein, γ-globulin, ceruloplasmin, and lysozyme activity. Eggs and dead parasites were excreted until day 3 postivermectin treatment. The reappearance of eggs was observed in 1 horse on day 50, and on day 75 in the remaining animals. Before treatment, total protein levels were measured at 53.2 g/L on average, and a decrease was noted until day 3 after treatment, with minor fluctuations on the following days. The highest γ-globulin concentrations of 14.1 g/L were reported on day 10 after treatment. Ceruloplasmin levels were determined at 74 IU before treatment, and a significant increase to 106 IU was observed on day 40. Lysozyme activity before ivermectin treatment reached 2.77 mL/L on average, and a significant 2-fold increase to 6.85 mg/L was reported on day 75. [ABSTRACT FROM AUTHOR]

Objective--To quantify the number of horses with Corynebacterium pseudotuberculosis infection identified in the United States from January 2003 through December 2012. Design--Cross-sectional study. Procedures--44 state veterinary diagnostic laboratories throughout the United States were invited by mail to participate in the study. Data requested included the number of C pseudotuberculosis culture-positive samples from horses identified per year, geograph-ic location from which the C pseudotuberculosis culture-positive sample was'submitted, month and year of sample submission, breed and age of horses, and category of clinical manifestation (ie, internal infection, external infection, or ulcerative lymphangitis). Results--Of the 44 invited laboratories, 15 agreed to participate and provided data on affected horses from 23 states. The proportion of C pseudotuberculosis culture-positive samples submitted during 2011 through 2012 (1,213/2,237 [54%]) was significantly greater than that for the period from 2003 through 2010 (1,024/2,237 [46%]). Corynebacterium pseudotuberculosis was recovered from horses in states where the disease has not been previously recognized as endemic. Affected horses were identified year-round. The greatest proportion of C pseudotuberculosis culture-positive samples was identified during Novem-ber, December, and January (789/2,237 [35%]). No significant association between the clinical form of disease and age or breed of horse was observed. Conclusions and Clinical Relevance--The occurrence of C pseudotuberculosis infection in horses increased during the 10-year period, and affected horses were identified through-out the United States. Further studies to determine changes in annual incidence and to identify potential changing climatic conditions or vector populations associated with dis-ease transmission are warranted to help control the occurrence and spread of C pseudotu-berculosis infection in horses. [ABSTRACT FROM AUTHOR]

Resistance to all of the licensed classes of anthelmintics is now widespread and targeted worming strategies are advocated to reduce selection pressure and delay the onset of anthelmintic resistance. Targeted strategies of worm control are relatively straightforward in adult horses but where youngstock are present the situation becomes more complicated. Youngstock are more susceptible to infection and clinical disease and additional parasites have to be considered in control programmes. Despite the additional complexity, targeted worming strategies can be employed on breeding establishments, and indeed should be, as owners of young horses have the most to lose if anthelmintic resistance develops. [ABSTRACT FROM AUTHOR]

Abstract: Leukotrienes are products of the arachidonic acid metabolism and act as potent inflammatory mediators modulating the immune response and various physiological processes. This study evaluated the expression and activity of 5-lipoxygenase (5-LOX), the enzyme that catalyzes the first two steps in the biosynthesis of leukotrienes, in horses infected by larval cyathostomins. Tissue samples from dorsal and ventral colon, and from the cecum were collected from 16 horses slaughtered for human consumption. Samples were analyzed to estimate the burdens of encysted cyathostomin larvae and adult luminal stages, and then processed for the evaluation of biochemical parameters. No significant differences were found in the protein expression and enzymatic activity of 5-LOX between animals harbouring only adult parasites and negative horses. The protein expression and enzyme activity of 5-LOX were significantly higher in horses harbouring encysted larvae in comparison with horses free of encysted larvae. Although preliminary, these results indicate that 5-LOX is an important mediator in the course of horse cyathostominosis and further studies are warranted to unveil the possible role this enzyme plays in the pathogenesis of horse cyathostominosis, and its potential as a diagnostic marker. [Copyright &y& Elsevier]

Equine infection with Corynebacterium pseudotuberculosis can manifest in several forms, including external or internal abscesses. The objective of this study was to phenotype clinical isolates of C. pseudotuberculosis and to investigate the relationship between lesion location and extent of lesions in the animals from which they were collected. One hundred and seventy-one C. pseudotuberculosis biovar equi isolates were collected from horses presenting to the University of California Veterinary Medical Teaching Hospital and two other sources in the period between September 1996 and December 2011. Bacteria! isolates were grouped on the bases of biochemical characteristics and growth on brain heart infusion agar. Six phenotypes were identified: (1) large colonies that metabolized sucrose (n = 81); (2) large sucrose-negative colonies (n = 47); (3) medium sucrose-positive (n = 20); (4) medium sucrose-negative (n = 11); (5) small sucrose-positive (n = 7), and (6) small sucrose-negative (n = 5). Medical records corresponding to each isolate were accessed from the University's administrative computer system or from the submitting source in order to determine the anatomical site from which the isolate was collected (n = 171), as well as the extent of lesions (n = 164) in the patient. The relationship between phenotype, lesion location and extent of lesions was then investigated statistically. No significant relationship between strain and lesion location or extent of lesions was found. This suggests that phenotypic differences during in vitro culture does not account for external versus internal disease in horses. Further work to characterize strains genotypically and to identify determinants for bacterial virulence should be performed. Importantly, host and environmental factors should also be further investigated. [ABSTRACT FROM AUTHOR]

Abstract: Strongylus vulgaris is regarded as the most pathogenic helminth parasite infecting horses. Migrating larvae cause pronounced endarteritis and thrombosis in the cranial mesenteric artery and adjacent branches, and thromboembolism can lead to ischemia and infarction of large intestinal segments. A recently developed serum ELISA allows detection of S. vulgaris-specific antibodies during the six-month-long prepatent period. A population of horses has been maintained at the University of Kentucky without anthelmintic intervention since 1979, and S. vulgaris has been documented to be highly prevalent. In 2012, 12 foals were born in this population, and were studied during a 12-month period (March–March). Weekly serum samples were collected to monitor S. vulgaris specific antibodies with the ELISA. Nine colts underwent necropsy at different time points between 90 and 300 days of age. At necropsy, Strongylus spp. and Parascaris equorum were identified to species and stage and enumerated. Initial statistical findings indicate a significant interaction between foal age and ELISA results (p <0.042). All foals had initial evidence of S. vulgaris-directed maternal antibodies transferred in the colostrum, but then remained ELISA negative during their first three months of life. Foals born in February and March became ELISA positive at about 12 weeks of age, while those born in April and May went positive at about 15 and 21 weeks, respectively. Foal date of birth was significantly associated with ELISA results (p <0.0001). This could be explained by birth date-dependent differences in parasite exposure. One foal remained ELISA-negative throughout the course of 30 weeks during the study. A significant association was found between ELISA values and larval S. vulgaris burdens (p <0.0001) as well as a three-way interaction between S. vulgaris, S. edentatus, and P. equorum burdens (p <0.001). A plateau with a subsequent decline in ELISA values corresponded with S. vulgaris larvae leaving the bloodstream and migrating back to the intestine. [Copyright &y& Elsevier]

Abstract: Equine trypanosomosis (ET) is a protozoan disease affecting equines in many parts of the world. We examined 509 samples collected from geographically distinct regions in eastern, central and western Sudan to estimate the endemicity of ET using the generic ITS1-PCR diagnostic methods. Results revealed that horses and donkeys were infected by Trypanosoma brucei subgroup, Trypanosoma vivax, Trypanosoma simiae and Trypanosoma congolense. The prevalence of Trypanosoma spp. was higher in horses (12.7%, n =393) than in donkeys (3.4%, n =116). The highest prevalence was observed in South Darfur State (19.3%, n =202), followed by Kassala State (15.1%, n =86), Gadaref State (3.7%, n =82), and Khartoum State (2.6%, n =76). No trypanosomes were detected in the 63 samples collected from North Kurdofan State. We report for the first time the presence of T. simiae and T. congolense in horses in the Sudan. This study should alert veterinary services, authorized bodies to take action toward ET by undertaking countrywide epidemiological studies of the disease and adopting control strategies. [Copyright &y& Elsevier]