The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Bhardwaj A, Tandon G, Pal Y, Sharma NK, Nayan V, Soni S, Iquebal MA, Jaiswal S, Legha RA, Talluri TR, Bhattacharya TK, Kumar D, Rai A, Tripathi BN.The horse, one of the most domesticated animals, has been used for several purposes, like transportation, hunting, in sport, or for agriculture-related works. Kathiawari, Marwari, Manipuri, Zanskari, Bhutia, Spiti, and Thoroughbred are the main breeds of horses, particularly due to their agroclimatic adaptation and role in any kind of strong physical activity, and these characteristics are majorly governed by genetic factors. The genetic diversity and phylogenetic relationship of these Indian equine breeds using microsatellite markers have been reported, but further studies exploring the SNP d...
Alm YH, Osterman-Lind E, Martin F, Lindfors R, Roepstorff N, Hedenström U, Fredriksson I, Halvarsson P, Tydén E.Cyathostominae are ubiquitous to grazing horses and regarded the most prevalent internal parasite in the horse. Unfortunately, decades of indiscriminate use of anthelmintic drugs have resulted in the development of resistance in cyathostomins to all currently available drug groups, the most recent being a documented lack of efficacy to the macrocyclic lactones (ML). In vivo determination of anthelmintic resistance in horses most often utilises the faecal egg count reduction test (FECRT). Further, a shortened egg reappearance period (ERP) can indicate a change in response to the applied treatme...
Spoormakers TJ, Heim C, Vermunt L, Fürst A, Rovel T.To describe clinical and imaging features and surgical treatment of equine mandibular aneurysmal bone cysts (ABCs) with β-tricalcium phosphate (TCP). Methods: 3 horses (cases 1, 2, and 3) and 1 pony (case 4) with histologically confirmed ABC. Methods: All cases had mandibular swelling with intact adjacent skin. Cases 1 to 3 had a body condition score of 3/5 and case 4 had 2/5 and showed quidding during mastication and, at oral examination, large interdental spaces and loose elements adjacent to the swelling. Radiography or CT was performed in all cases. In cases 1, 3, and 4, an expansile sept...
Bennet ED, Parkin TDH.Racehorse training and racing schedules in many parts of the United States and Canada were interrupted or otherwise reduced during the first three to six months of 2020. This was an indirect consequence of mitigations to prevent the spread of the pandemic virus COVID-19. Data from the Equine Injury Database, a census-level survey of all race starts made in the USA and Canada, were used to analyse the incidence of fatalities in 2009-2022 among three age cohorts of racehorses within each year. There was a statistically significant increase in the incidence of musculoskeletal fatalities among 2-y...
Górski K, Borowska M, Turek B, Pawlikowski M, Jankowski K, Bereznowski A, Polkowska I, Domino M.Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) syndrome is a dental disease where the radiographic signs may be quantified using radiographic texture features. This study aimed to implement the scaled-pixel-counting protocol to quantify and compare the image structure of teeth and the density standard in order to improve the identification of the radiographic signs of tooth resorption and hypercementosis using the EOTRH syndrome model. Results: A detailed examination of the oral cavity was performed in 80 horses and maxillary incisor teeth were evaluated radiographically, in...
Faghihzadeh Gorji F, Sadr S, Sharifiyazdi H, Borji H.Parasitic infections pose significant threats to humans' and animals' well-being worldwide. Among these parasites, Halicephalobus spp., a genus of nematodes, has gained attention due to its ability to cause severe infections in various animal species, including horses. Objective: This study aimed to determine the prevalence of Halicephalobus spp., specifically focusing on Halicephalobus gingivalis in horses. Methods: In July 2022, a cross-sectional study was conducted in northern Iran to determine the prevalence of Halicephalobus spp. Using standard coprological techniques, 141 fecal samples f...
Jondeau C, Guyonnet A, Losada A, Laloy E, Reyes-Gomez E, Le Dudal M, Chahory S.To describe a case of lipogranulomatous conjunctivitis in a horse. Methods: A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses. Methods: Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed. Results: Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflam...
Amory H, Cesarini C, De Maré L, Loublier C, Moula N, Detilleux J, Saulmont M, Garigliany MM, Lecoq L.The objective of this retrospective study was to evaluate the clinical significance of fecal quantitative real-time polymerase chain reaction (qPCR) results when taking the cycle threshold values (Ct) into account. The study included 120 qPCR-positive fecal samples obtained from 88 hospitalized horses over a 2-year period. The mean Ct of the qPCR test was evaluated in regard to (1) clinical outcome and (2) systemic inflammatory response syndrome (SIRS) status (no SIRS, moderate SIRS, or severe SIRS) of the sampled horses. An ROC analysis was performed to establish the optimal cut-off Ct valu...
Rule EK, Boyle AG, Stefanovski D, Anis E, Linton J, Lorello O.Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Objective: That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Methods: Twenty-two healthy mare-foal pairs. ...
Amairia S, Jbeli M, Mrabet S, Jebabli LM, Gharbi M.Sarcocystis spp. and Toxoplasma gondii are two apicomplexan protozoa that infect a broad range of vertebrates, however, little is known about the infection of equids with these parasites. A total of 184 slaughtered equids from slaughterhouses of Bizerte and Tunis located in Northern Tunisia, were examined for meat infections with Sarcocystis spp. and T. gondii by PCR. The prevalence of infections with Sarcocystis spp. and T. gondii were 38% (95% CI: 31-45) and 39.7% (95% CI: 32.6-46.7), respectively. The highest prevalence of infection with Sarcocystis spp. was observed in donkeys (48.6%; 95%C...
van den Wollenberg L, van Maanen C, Buter R, Janszen P, Rey F, van Engelen E.Abscessation of equine head lymph nodes can be caused by various bacteria, but Streptococcus equi subsp. equi is mainly involved. At our laboratory, samples of three unrelated horses with submandibular abscesses were found negative for S. equi, and further testing proved the presence of another genus. This raised the question for the exact identity of this pathogen and whether these isolates were epidemiologically related and it warranted further characterization with regards of virulence and resistance factors.
Sewgobind S, McCracken F, Schilling M.West Nile virus (WNV) is a positive-sense single-stranded RNA virus belonging to the Flaviviridae family and is maintained in an enzootic cycle between avian hosts and mosquito vectors. Humans, horses and other mammals are susceptible to infection but are dead-end hosts due to a low viraemia. The disease can manifest itself in a variety of clinical signs and symptoms in people and horses from mild fever to severe encephalitis and morbidity. There are no vaccines licensed for human protection, but parts of Europe, North America, Africa and Australia have vaccines commercially available for hors...
Bergmann R, Schroedl W, Müller U, Baums CG.Streptococcus equi subsp. zooepidemicus (SEZ) is a major equine pathogen that causes pneumonia, abortion, and polyarthritis. It can also cause invasive infections in humans. SEZ expresses the M-like protein SzM, which recruits host proteins such as fibrinogen to the bacterial surface. Equine SEZ strain C2, which binds only comparably low amounts of human fibrinogen in comparison to human SEZ strain C33, was previously shown to proliferate in equine and human blood. As the expression of SzM_C2 was necessary for survival in blood, this study investigated the working hypothesis that SzM_C2 inhibi...
Pezzanite LM, Chow L, Dow SW, Goodrich LR, Gilbertie JM, Schnabel LV.Increasing antimicrobial resistance in veterinary practice has driven the investigation of novel therapeutic strategies including regenerative and biologic therapies to treat bacterial infection. Integration of biological approaches such as platelet lysate and mesenchymal stromal cell (MSC) therapy may represent adjunctive treatment strategies for bacterial infections that minimize systemic side effects and local tissue toxicity associated with traditional antibiotics and that are not subject to antibiotic resistance. In this review, we will discuss mechanisms by which biological therapies exe...
de Souza RP, Mousquer MA, Müller V, Barbosa JCR, Leite FPL, Guedes RMC, Curcio BDR, Nogueira CEW.The aim of the present study was to carry out a serological survey to identify the seroprevalence of Lawsonia intracellularis in six Thoroughbred farms in the Southern region of the state of Rio Grande do Sul, Brazil. During 2019 and 2020, blood samples from 686 Thoroughbred horses were obtained from six different breeding farms. Horses were divided into groups according to age: (1) broodmares (>5 years), (2) two-year-old foals, (3) yearlings, and (4) 0-6 months-old foals. Blood samples were collected by venipuncture of the external jugular vein. The detection of antibodies (IgG) against L. in...
McCue PM, Bisiau C, Divine C, May E.Congential amastia, a medical condition in which mammary tissue fails to develop, was detected in a 3-year-old Quarter Horse mare. The dam of the mare was also afflicted with amastia, suggesting that the condition was due to an inherited genetic mutation as noted in other species. In addition, on presentation the mare had a purulent vaginal discharge secondary to a pyometra.
de Melo UP, Ferreira C.Oral and dental diseases are common in horses, as evidenced by the results of incidence studies of dental diseases carried out on abattoir specimens or sports horses. Thus, periodic dental examinations in horses are essential to ensure the maintenance of dental health and proper use of ingested food. A retrospective study of the dental records of 416 Quarter Horses (256 males, 160 females), distributed in the western region of the Rio Grande do Norte, Brazil, was conducted. Horses were examined between July 2012 and August 2022. The variables collected were age, sex, type of diet, dental alter...
Wang XF, Zhang X, Ma W, Li J, Wang X.Equine infectious anemia virus (EIAV) is a member of the lentivirus genus in the Retroviridae family and is considered an animal model for HIV/AIDS research. An attenuated EIAV vaccine, which was successfully developed in the 1970s by classical serial passage techniques, is the first and only lentivirus vaccine that has been widely used to date. Restriction factors are cellular proteins that provide an early line of defense against viral replication and spread by interfering with various critical steps in the viral replication cycle. However, viruses have evolved specific mechanisms to overcom...
Gorji FF, Sadr S, Borji H.Eimeria is a genus of protozoan parasites that infect many animal species, including horses. We conducted a cross-sectional study of indigenous breeds of horses from the North and Northeast of Iran to establish the prevalence and distribution of Eimeria species. Methods: Using standard coprological techniques, 340 faecal samples from randomly selected horses (141 from North Iran and 199 from Northeast Iran) were examined for Eimeria oocyst. Results: Out of 340 samples, only three from north Iran were positive for coccidiosis. Infections occurred by Eimeria leuckarti. The mean intensity of oocy...
Townsend KS, Johnson PJ, Kuroki K.Primary squamous cell carcinoma of the head and neck occurs in the skin or squamous epithelial lining tissues of the oral cavity, pharynx, larynx, and sinonasal tract. Although it is a common tumor in horses, distant metastatic spread to the lung is rare. This report describes a case of metastatic pulmonary squamous cell carcinoma in a 23-year-old Morgan gelding. The clinical signs displayed by this gelding in some ways mimicked the typical presentation of equine multinodular pulmonary fibrosis or thoracic lymphoma. The postmortem diagnosis in this case was head and neck squamous cell carcinom...
Clark B, Steel C, Vokes J, Shan JR, Gedye K, Lovett A, Sykes BW.Rebound gastric hyperacidity (RGH) secondary to hypergastrinemia has been suggested to contribute to the rapid recurrence of equine squamous gastric disease (ESGD) in horses after discontinuation of omeprazole. Objective: To evaluate changes in serum gastrin and chromogranin A (CgA) concentrations in response to medium-term (57-day) omeprazole treatment and after omeprazole discontinuation. Methods: Fourteen mature Thoroughbred racehorses in simulated race training. Methods: Horses received 2.28 g of oral omeprazole PO q24h for 57 days within a 61-day period, excluding a withholding period...
Elata A, Galon EM, Moumouni PFA, Ybanez RHD, Mossaad E, Salces CB, Bajenting GP, Ybanez AP, Xuan X, Inoue N, Suganuma K.Animal trypanosomosis is one of the most important parasitic diseases significantly affecting the Philippine economy. It is considered by the government to be the second most important disease of livestock after fasciolosis. A PCR-based molecular survey for trypanosomes in different animals in Bohol, Philippines, was performed to assess the prevalence of trypanosomosis in the area during the rainy and dry season. Methods: A total of 269 blood samples were collected in two batches in rainy and dry season from different animal species in Ubay Stock Farm in Ubay, Bohol, the Philippines, including...
Onder Z, Yildirim A, Duzlu O, Ciloglu A, Yetismis G, Karabulut F, Inci A.This study was conducted to determine single nucleotide polymorphisms (SNPs) and the benzimidazole (BZ) resistance in strongyle nematode egg populations in horses using molecular techniques. A total of 200 fecal samples were collected from horses in 26 farms in two provinces (Kayseri and Nevşehir) of the Central Anatolia Region of Türkiye between May and August 2022. The flotation method was used to detect strongyle nematode eggs in the fecal samples of the horses. Afterward, strongyle nematode eggs were collected, and the allele-specific polymerase chain reaction (AS-PCR) technique was used...
Zúñiga MP, Badillo E, Abalos P, Valencia ED, Marín P, Escudero E, Galecio JS.Rhodococcus equi is responsible for foal pneumonia worldwide, with a significant economic impact on the production and breeding of horses. In Chile, the first case was reported in 2000, and since then, its incidence has been increasing. Distinctive characteristics of R. equi as an intracellular pathogen in macrophages, emergence of virulence plasmids encoding surface lipoprotein antigens, and appearance of antibiotic resistance against macrolides and rifampicin have significantly complicated the treatment of R. equi pneumonia in foals. Therefore, in vitro susceptibility studies of first-line a...
Azhar M, Gadahi JA, Bhutto B, Tunio S, Vistro WA, Tunio H, Bhutto S, Ram T.Babesiosis is a protozoal disease affect livestock and pet animals such as cattle, buffaloes, sheep, goats, horses, donkeys, mules, dogs, and cats. It causes severe economic losses in livestock as well as in pet animals. A large number of dairy animals are imported in order to fulfill the demands of milk, milk, meat and its products. In addition, different pet animals are transported from Pakistan to various parts of the world, therefore, it is important to identify the current status and distribution of babesiosis throughout Pakistan in order to control the disease and draw attention for futu...
Beckers KF, Gomes VCL, Crissman KR, Liu CC, Schulz CJ, Childers GW, Sones JL.Placentitis is the leading cause of infectious abortion in the horse. Additionally, it can result in weak and/or growth restricted offspring. While the etiology of ascending placentitis is well described in mares, less is known regarding the pathogenesis of other types, such as nocardioform placentitis. This study aims to identify the microbial communities in different body sites of the pregnant mare in early gestation to establish a core microbiome that may be perturbed in pathologic pregnancies such as placentitis. We hypothesize that the equine placenta harbors a distinct resident microbiom...
Kozłowska N, Wierzbicka M, Pawliński B, Domino M.According to the "unified or united airway disease" theory, diseases in the upper and lower airways frequently co-occur because they represent a single morphological and functional unit. Palatal disorders (PDs) and severe equine asthma (SEA) are frequent diseases that, respectively, affect upper and lower equine airways; however, clinical studies focusing on the co-occurrence of PDs and SEA are limited. The present study investigated the prevalence of PDs in horses affected by SEA, and whether prevalence decreased after SEA treatment. Forty-six privately owned horses affected by SEA in exacerb...
Kakoi H, Kikuchi M, Ishige T, Hirosawa Y, Tanaka S, Nagata SI.To confirm the positive conversion of antibodies against erythrocyte antigens in horses, possible blood transfusion donor horses selected from draft horse populations were periodically monitored with an indirect antiglobulin (Coombs) test for approximately 3 years. In this study, 19 horses (16 females and 3 males) were investigated, and five mares showed alloantibodies during the monitoring period. Four mares were typically pregnant when positive conversion was detected, whereas no particular cause of conversion could be observed for one mare based on its clinical records. In the analyzed hors...
Dolin A, Schweiger P, Waselau M, Egerbacher M, Walter I.Sex cord-stromal tumors (SCSTs), generally referred to as granulosa cell tumors (GCTs) or granulosa-theca cell tumors (GTCTs) in equids, show complex compositions and variable numbers of hormone-producing cells. These tumors can be difficult to diagnose, especially in early stages. Therefore, we tested a panel of antibodies for vimentin, smooth muscle actin, laminin, Ki-67, E-cadherin, calretinin, moesin, p-ezrin, AMH, and aromatase, markers used for tumor composition and classification, progression, and prognosis in human SCSTs, on an exemplary grapefruit-size equine GCT within the left ovary...
Braga FR, Araújo JV, Silva AR, Araujo JM, Carvalho RO, Tavela AO, Campos AK, Carvalho GR.The viability of a fungal formulation using the nematode-trapping fungus Duddingtonia flagrans was assessed for the biological control of horse cyathostomin. Two groups (fungus-treated and control without fungus treatment), consisting of eight crossbred mares (3-18 years of age) were fed on Cynodon sp. pasture naturally infected with equine cyathostome larvae. Each animal of the treated group received oral doses of sodium alginate mycelial pellets (1g/(10 kg live weight week)), during 6 months. Significant reduction (p<0.01) in the number of eggs per gram of feces and coprocultures was foun...
Denwood MJ, Love S, Innocent GT, Matthews L, McKendrick IJ, Hillary N, Smith A, Reid SW.The faecal egg count (FEC) is the most widely used means of quantifying the nematode burden of horses, and is frequently used in clinical practice to inform treatment and prevention. The statistical process underlying the FEC is complex, comprising a Poisson counting error process for each sample, compounded with an underlying continuous distribution of means between samples. Being able to quantify the sources of variability contributing to this distribution of means is a necessary step towards providing estimates of statistical power for future FEC and FECRT studies, and may help to improve t...
Hübert PH, Birkenmaier S, Rziha HJ, Osterrieder N.The equine herpesvirus type-1 modified live-vaccine strain RacH (256th passage on porcine embryonic kidney cells) was investigated by restriction-enzyme analysis and compared to representative plaque isolates of the 12th passage (RacL11, RacL22) and 185th passage (RacM24, RacM36). The restriction patterns of all Rac plaque isolates differed compared with reference strain Ab4. The left UL terminus was shortened by 0.1 kbp and a missing BamHI site led to the fusion of the f and t fragments. In some Rac derivatives, losses of restriction sites without deletions were observed: 1. One BamHI site lo...
Novilla MN.Monensin, lasalocid, salinomycin, narasin and maduramicin are carboxylic ionophores intended for use as anticoccidial drugs for poultry and as growth promotants for ruminants. Generally, ionophores have been found safe and effective in the target animals receiving recommended dosage levels. However, toxic syndromes can result from overdosage and misuse situations. More information and reports of adverse reactions are available for monensin than the other ionophores because of monensin's longstanding and widespread use in the poultry and livestock industries. Care must be exercised in the diagn...
van der Rijt R, van den Boom R, Jongema Y, van Oldruitenborgh-Oosterbaan MM.The aims of this study were to determine (1) which species of Culicoides is most commonly attracted to horses, (2) whether horses suffering insect hypersensitivity attract more Culicoides spp. than unaffected horses, and (3) the times when Culicoides spp. are most active. Horses affected by insect hypersensitivity and unaffected horses were placed inside mosquito netting tents for 30 min at different times of the day. All Culicoides spp. trapped inside the tents were collected and identified. C. obsoletus was the most common species found, followed by C. pulicaris. Healthy horses attracted sli...
van Biervliet J, Scrivani PV, Divers TJ, Erb HN, de Lahunta A, Nixon A.Different criteria have been described based on height reduction of the total myelographic contrast column and components of it as tests for compression of the spinal cord due to cervical stenotic myelopathy (CSM). Fifty percent height reduction of the dorsal myelographic column (DMC), <2 mm empiric height of the DMC and a 40% reduction of the ratio of stenosis calculated based on the height reduction of the entire dural diameter (DD) have been described as decision criteria for considering the test result positive. The reasons for selecting these decision criteria or their accuracies have ...
Swinburne JE, Bogle H, Klukowska-Rötzler J, Drögemüller M, Leeb T, Temperton E, Dolf G, Gerber V.Recurrent airway obstruction (RAO), or heaves, is a naturally occurring asthma-like disease that is related to sensitisation and exposure to mouldy hay and has a familial basis with a complex mode of inheritance. A genome-wide scanning approach using two half-sibling families was taken in order to locate the chromosome regions that contribute to the inherited component of this condition in these families. Initially, a panel of 250 microsatellite markers, which were chosen as a well-spaced, polymorphic selection covering the 31 equine autosomes, was used to genotype the two half-sibling familie...
Leon IM, Lawhon SD, Norman KN, Threadgill DS, Ohta N, Vinasco J, Scott HM.Although Salmonella enterica can produce life-threatening colitis in horses, certain serotypes are more commonly associated with clinical disease. Our aim was to evaluate the proportional morbidity attributed to different serotypes, as well as the phenotypic and genotypic antimicrobial resistance (AMR) of Salmonella isolates from patients at an equine referral hospital in the southern United States. A total of 255 Salmonella isolates was obtained from clinical samples of patients admitted to the hospital between 2007 and 2015. Phenotypic resistance to 14 antibiotics surveilled by the U.S. Nati...
Rieger M, Kochleus C, Teschner D, Rascher D, Barton AK, Geerlof A, Kremmer E, Schmid M, Hartmann A, Gehlen H.In human medicine, procalcitonin (PCT) is a very common and well-established biomarker for sepsis. Even though sepsis is also a leading cause of death in foals and adult horses, up to now, no data about the role of equine PCT in septic horses has been available. Based on monoclonal antibodies targeted against human PCT, we report here the development of a sandwich ELISA for the quantification of equine PCT in equine plasma samples. The ELISA was characterized for intra- and interassay variance and a working range from 25 to 1,000 ng mL(-1) was defined as within this range; both intra- and in...
Pisello L, Rampacci E, Stefanetti V, Beccati F, Hyatt DR, Coletti M, Passamonti F.This study aimed to describe bacteria isolated from the reproductive tract of mares and to identify changes in antimicrobial susceptibility patterns to those antibiotics commonly used for the treatment of equine endometritis. A total of 4122 equine uterine swabs were collected from mares suffering from reproductive tract disorders in the period 2010-2017. Aerobic culture and antimicrobial susceptibility testing using agar disc diffusion were performed on each sample. Aerobic bacteria were isolated from 3171 of 4122 (76.9 per cent) samples. The most frequently isolated microorganisms were (885...
Guthrie AJ, Maclachlan NJ, Joone C, Lourens CW, Weyer CT, Quan M, Monyai MS, Gardner IA.Blood samples collected from 503 suspect cases of African horse sickness (AHS) and another 503 from uninfected, unvaccinated South African horses, as well as 98 samples from horses from an AHS free country, were tested with an AHS virus (AHSV) specific duplex real-time reverse transcription quantitative PCR (RT-qPCR) assay and virus isolation (VI). The diagnostic sensitivity and specificity of this AHSV RT-qPCR assay and VI were estimated using a 2-test 2-population Bayesian latent class model which made no assumptions about the true infection status of the tested animals and allowed for the p...
Meister TL, Tegtmeyer B, Postel A, Cavalleri JV, Todt D, Stang A, Steinmann E.An equine parvovirus-hepatitis (EqPV-H) has been recently identified in association with equine serum hepatitis, also known as Theiler's disease. This disease was first described by Arnold Theiler in 1918 and is often observed after applications with blood products in equines. So far, the virus has only been described in the USA and China. In this study, we evaluated the presence of EqPV-H in several commercial serum samples to assess the potential risk of virus transmission by equine serum-based products for medical and research applications. In 11 out of 18 commercial serum samples, EqPV-H D...
Bacciarini LN, Boerlin P, Straub R, Frey J, Gröne A.Clostridia-associated intestinal disease in horses was generally reported to be due to infection with Clostridium perfringens type A, which harbors the cpa-encoded alpha-toxin. A recent study demonstrated a high incidence of beta2-toxigenic C. perfringens in horses suffering or dying from typhlocolitis, suggesting that this novel type of C. perfringens might play an important role in typhlocolitis and possibly other equine intestinal diseases. A retrospective study was conducted to assess the presence of the beta2-toxin in tissues of the equine gastrointestinal tract. Monospecific polyclonal a...
Bosco A, Maurelli MP, Ianniello D, Morgoglione ME, Amadesi A, Coles GC, Cringoli G, Rinaldi L.Nematode infections in horses are widespread across the world. Increasing levels of anthelmintic resistance, reported worldwide in equine parasites, have led to the creation of programs for the control of nematodes based on faecal egg counts (FEC). To improve nematode egg counting in equine faecal samples and establish whether the matrix of equine faeces or the eggs affect the counts, the analytical sensitivity, accuracy and precision of Mini-FLOTAC (combined with Fill-FLOTAC), McMaster and Cornell-Wisconsin techniques were compared. Known numbers of eggs extracted from equine or ovine faeces ...
Rodríguez-Lázaro D, Lewis DA, Ocampo-Sosa AA, Fogarty U, Makrai L, Navas J, Scortti M, Hernández M, Vázquez-Boland JA.We developed a novel quantitative real-time PCR (Q-PCR) method for the soil actinomycete Rhodococcus equi, an important horse pathogen and emerging human pathogen. Species-specific quantification was achieved by targeting the chromosomal monocopy gene choE, universally conserved in R. equi. The choE Q-PCR included an internal amplification control (IAC) for identification of false negatives. A second Q-PCR targeted the virulence plasmid gene vapA, carried by most horse isolates but infrequently found in isolates from other sources. The choE-IAC and vapA assays were 100% sensitive and specific ...
Gerhard AP, Krücken J, Heitlinger E, Janssen IJI, Basiaga M, Kornaś S, Beier C, Nielsen MK, Davis RE, Wang J, von Samson-Himmelstjerna G.P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the maj...
Borchers K, Wolfinger U, Ludwig H.Equine herpesvirus type 4 (EHV-4) is a major respiratory pathogen of horses. Unlike most other members of the Alphaherpesvirinae, EHV-4 was regarded as non-neurotropic. Here, neural and lymphoid tissues of 17 horses have been analysed post-mortem. EHV-4 DNA was detected in 11 cases (65%) by PCR, exclusively in the trigeminal ganglia. In order to define the transcriptional activity, RNA preparations of 10 EHV-4 DNA-positive ganglia were investigated by nested RT-PCR. EHV-4-specific transcripts derived from genes 63 [herpes simplex virus type 1 (HSV-1) ICPO gene homologue] and 64 (HSV-1 ICP4 gen...
Peckle M, Pires MS, Dos Santos TM, Roier EC, da Silva CB, Vilela JA, Santos HA, Massard CL.The aim of this study was to detect Theileria equi (Laveran 1901) DNA in horses and ticks using real-time PCR and to list the factors associated with infection in animals located in the Seropedica and Petropolis municipalities of the state of Rio de Janeiro. We tested blood samples from 314 horses and samples from 300 ticks, including 191 Amblyomma cajennense, 104 Dermacentor nitens, and 5 Ixodida larvae. Factors inherent to the horse, the ownership, and animal management were obtained from an epidemiological questionnaire and were evaluated in association with the presence of T. equi DNA in t...
Lin C, Holland RE, Donofrio JC, McCoy MH, Tudor LR, Chambers TM.Equine influenza virus (EIV) is the leading cause of acute respiratory infection in horses worldwide. In recent years, the precise mechanism by which influenza infection kills host cells is being re-evaluated. In this report, we examined whether caspases, a group of intracellular proteases, are activated following EIV infection and contribute to EIV-mediated cell death. Western blotting analysis indicated that a nuclear target of caspase-3, poly(ADP-ribose) polymerase (PARP) was proteolytically cleaved in EIV-infected MDCK cells, but not in mock-infected cells. In comparison with caspase-3 spe...
Ayoub C, Arroyo LG, MacNicol JL, Renaud D, Weese JS, Gomez DE.The association of microbiota with clinical outcomes and the taxa associated with colitis in horses remains generally unknown. Objective: Describe the fecal microbiota of horses with colitis and investigate the association of the fecal microbiota with the development of laminitis and survival. Methods: Thirty-six healthy and 55 colitis horses subdivided into laminitis (n = 15) and non-laminitis (n = 39, 1 horse with chronic laminitis was removed from this comparison) and survivors (n = 27) and nonsurvivors (n = 28). Methods: Unmatched case-control study. The Illumina MiSeq platform tar...
Turtinen LW, Allen GP, Darlington RW, Bryans JT.The molecular and serologic relatedness of 2 recent respiratory tract isolates of equine herpesvirus type 1, designated T1 and T2, were compared with the Army 183, Kentucky-A hamster-adapted (KyA-ha), and L-M cell-adapted (KyA-LM) strains. Electrophoresis in polyacrylamide gels revealed differences in virion structural proteins among 4 purified strains. Seven envelope glycoproteins (molecular weight of 93,000, 65,000, 62,000, 60,000, 36,000, 20,000, and 18,000) corresponding to virion proteins 13, 16, 17, 18, 23, 25, and 26a, respectively, found in both the Army 183 and KyA-ha strains had slig...
Isa P, Wood AR, Netherwood T, Ciarlet M, Imagawa H, Snodgrass DR.DIG-labelled ssRNA probes were prepared from variable regions of VP4 and VP7 cognate genes, and used in hybridization assays for P and G genotyping of group A cell culture-adapted equine rotaviruses and fecal samples collected from foals with and without diarrhea. The probes confirmed known P and G serotypes of sixteen cell culture-adapted strains. From one-hundred and twenty-one rotavirus-positive samples, 83 reacted when tested for their P and G genotype specific probes. From these, 71 were found to contain G3 P12 genotypes, and 11 G14 P12 genotypes. No sample reacted with H1 or L338 P and G...
Barton MH, Collatos C.The purpose of this study was to evaluate the diagnostic and prognostic significance of tumor necrosis factor-alpha (TNF) and interleukin-6 (IL-6) activities and endotoxin concentration in blood and peritoneal fluid of 155 adult horses with acute abdominal disease (colic). Samples also were obtained from 20 healthy adult horses. Blood and peritoneal fluid supernatant TNF and IL-6 activities and endotoxin concentration were significantly greater in horses with colic, compared with healthy horses. In horses with colic, the peritoneal fluid endotoxin concentration and TNF and IL-6 activities were...
Sprague LD, Zachariah R, Neubauer H, Wernery R, Joseph M, Scholz HC, Wernery U.The internationally mandatory complement fixation test (CFT) for testing of equine sera for the absence of glanders has repeatedly led to discrepant results. Not only do "false positive" sera pose a problem for the diagnostician and the animal health authorities but they can also result in significant financial losses for the animal owners.Due to the very low prevalence of glanders in the horse population it is of major importance to use tests with a high specificity to overcome unreliable predictive values. We have compared formalin-fixed B. mallei whole cell antigen and a well characterised ...
Angulo-Valadez CE, Scholl PJ, Cepeda-Palacios R, Jacquiet P, Dorchies P.Larvae causing obligatory myiasis are numerous and they may affect cutaneous and subcutaneous tissues, wounds, nasopharyngeal cavities (nasal bots), internal organs and the digestive tract (bots) of domestic and wild animals and humans as well. Nasal bots belong to the Family Oestridae, Subfamily Oestrinae, which includes several important genera: Oestrus, Kirkioestrus, and Gedoelstia infecting Artiodactyla (except Cervidae) in Africa and Eurasia, Cephenemyia and Pharyngomyia infecting Cervidae, Rhinoestrus infecting horses, Cephalopina infecting camels, Pharyngobolus infecting African elephan...
Kurowski PB, Traub-Dargatz JL, Morley PS, Gentry-Weeks CR.To use real-time polymerase chain reaction (PCR) technology to develop a highly sensitive and specific diagnostic assay for the detection of Salmonella spp in fecal specimens. Methods: 299 fecal specimens from cattle, horses, and dogs. Methods: Enrichment of fecal specimens was followed by genomic DNA extraction by use of commercially available isolation kits. Real-time PCR assay was performed to target a Salmonella spp-specific DNA segment. Results of real-time PCR assay were compared with bacterial culture results to determine relative sensitivity and specificity. Results: Use of the spaQ pr...
Ikadai H, Xuan X, Igarashi I, Tanaka S, Kanemaru T, Nagasawa H, Fujisaki K, Suzuki N, Mikami T.A cDNA expression library prepared from Babesia caballi merozoite mRNA was screened with a monoclonal antibody BC11D against the rhoptry protein of B. caballi merozoite. A cDNA encoding a 48-kDa protein of B. caballi was cloned and designated BC48. The complete nucleotide sequence of the BC48 gene had 1,828 bp and was shown to contain no intron. Southern blotting analysis indicated that the BC48 gene contained more than two copies in the B. caballi genome. Computer analysis suggested that this sequence contained an open reading frame of 1,374 bp with a coding capacity of approximately 52 kDa. ...
Chirnside ED, Wearing CM, Binns MM, Mumford JA.cDNA copies of the M and N genes of equine arteritis virus (EAV) isolates were synthesized by reverse transcription followed by polymerase chain reaction amplification. The cDNA was subjected to a cycle sequencing strategy using Taq polymerase, and the nucleotide and derived amino acid sequences of 10 virus isolates were compared. The M and N genes of all isolates had the same initiation and termination sites as the prototype Bucyrus strain and the encoded proteins were conserved between viruses. Comparison of nucleotide sequence homologies and phylogenetic tree analysis implied the existence ...
Uzal FA, Navarro MA, Asin J, Henderson EE.The clostridial diseases of horses can be divided into three major groups: enteric/enterotoxic, histotoxic, and neurotoxic. The main enteric/enterotoxic diseases include those produced by Clostridium perfringens type C and Clostridioides difficile, both of which are characterized by enterocolitis. The main histotoxic diseases are gas gangrene, Tyzzer disease, and infectious necrotic hepatitis. Gas gangrene is produced by one or more of the following microorganisms: C. perfringens type A, Clostridium septicum, Paeniclostridium sordellii, and Clostridium novyi type A, and it is characterized by ...
Sanz M, Loynachan A, Sun L, Oliveira A, Breheny P, Horohov DW.While Rhodococcus equi remains the most common cause of subacute or chronic granulomatous bronchopneumonia in foals, development of a relevant model to study R. equi infection has proven difficult. The objective of this study was to identify a challenge dose of R. equi that resulted in slow progressive disease, spontaneous regression of lung lesions and age-dependent susceptibility. Foals less than one-week of age were challenged intratracheally using either 10(6), 10(5), 10(4), 10(3) or 10(2) cfu of R. equi. Two doses (10(3) cfu and 10(5) cfu) were used to challenge 2 and 3-week-old, and 3 an...
