Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Ryan CA, McNeal CD, Credille BC.Equine practitioners require recommendations that support antimicrobial stewardship and avoid generating resistance to medically important antibiotics. This review examines current inadequacies in antimicrobial stewardship standards within the veterinary community, related to antimicrobial categorisation and prescribing practices. Resistance to cephalosporin antibiotics in horses is also described. Properties of cephalosporin antibiotics are outlined and equine-specific studies of ceftiofur, a third-generation cephalosporin antibiotic with medical importance, are detailed. Readers are provided...
Elte Y, Acton K, Martin J, Nielen M, van Weeren R, Wolframm I.Individuals working in the field of veterinary care are regularly affected by their profession. High levels of responsibility to often provide life-saving health care to animals combined with having to manage owners' expectations and irregular working hours can cause considerable levels of work-related stress among professionals in equine veterinary practice. On the positive side, research also shows that working in the veterinary profession can have a positive impact on personal wellbeing and feelings of fulfillment. A limited number of studies has investigated work satisfaction and engagemen...
Pimentel F, McManus C, Soares K, Caetano AR, de Faria DA, Paiva SR, Ianella P.Optimization of DNA collection for National gene bank and conservation programs requires information on spatial and genetic distribution of animals countrywide. The relationship between genetic and geographic distances were examined in 8 Brazilian horse breeds (Baixadeiro, Crioulo, Campeiro, Lavradeiro, Marajoara, Mangalarga Marchador, Pantaneiro and Puruca) using Single Nucleotide Polymorphism markers and collection point locations. Mantel correlations, Genetic Landscape Shape Interpolation, Allelic Aggregation Index Analyses and Spatial autocorrelation tests indicated a nonrandom distributio...
van Bömmel-Wegmann S, Zentek J, Gehlen H, Barton AK, Paßlack N.The effects of dietary zinc on the immune function of equines have not been evaluated in detail so far. In the present study, eight healthy adult ponies and two healthy adult horses were fed a diet supplemented with either zinc chloride hydroxide or zinc methionine in six feeding periods of four weeks each (according to maintenance zinc requirement, 120 mg zinc/kg dry matter, and 240 mg zinc/kg dry matter, for both dietary zinc supplements, respectively). All animals received the six diets, with increasing amounts of zinc chloride hydroxide in the feeding periods 1-3, and with increasing a...
Karamendin K, Abishov A, Kydyrmanov A, Akhmetzhanova M.In 2011, there was an outbreak of a disease with mass abortions among horses in southeastern Kazakhstan. The AK-2011 strain was isolated from an aborted fetus and subsequently identified as equid alphaherpesvirus 1. Here, we describe the nearly complete genome sequence of the AK-2011 strain, attenuated for vaccine development.
Pratt-Phillips S, Munjizun A.There is ample research describing the increased risk of health concerns associated with equine obesity, including insulin dysregulation and laminitis. For athletes, the negative effect of weight carriage is well documented in racing thoroughbreds (i.e., handicapping with weight) and rider weight has been shown to impact the workload of ridden horses and to some degree their gait and movement. In many groups of competitive and athletic horses and ponies, obesity is still relatively common. Therefore, these animals not only are at risk of metabolic disease, but also must perform at a higher wor...
Johnson SE, Barshick MR, Gonzalez ML, Riley JW, Pelletier ME, Castanho BC, Ealy EN.Strenuous exercise can cause tissue damage, leading to an extended recovery period. To counteract delayed post-exercise recovery, a commercial product containing L-carnitine (AID) was tested in adult horses performing consecutive exercise tests to exhaustion. Fit Thoroughbreds were administered an oral bolus of placebo (CON) or AID prior to performing an exercise test to exhaustion (D1). The heart rate (HR) and fetlock kinematics were captured throughout the exercise test. Blood was collected before, 10 min and 1, 4 and 6 h relative to exercise for the quantification of cytokine (1, 8, 10, ) g...
Petry S, Breuil MF, Duquesne F.Contagious equine metritis (CEM) detection by PCR is recognized by the European Union according to Commission Implementing Regulation (EU) No 846/2014, and real-time PCR is now recommended by the World Organisation for Animal Health Terrestrial Manual at the same level as the culture method. The present study highlights the creation of an efficient network of approved laboratories in France in 2017 for CEM detection by real-time PCR. The network currently consists of 20 laboratories. A first proficiency test (PT) was organized by the national reference laboratory for CEM in 2017 to evaluate th...
Lin ST, Peter VG, Schiavo S, Pokora R, Patrick H, Bolas N, Foote AK, Sargan DR, Murray RC.Heterotopic mineralization in equine distal limbs has been considered an incidental finding and little is known about its imaging features. The study aimed to identify heterotopic mineralization and adjacent pathology in the fetlock region with cone-beam (CB) computed tomography (CT), fan-beam (FB) CT, and low-field magnetic resonance imaging (MRI). Images from 12 equine cadaver limbs were examined for heterotopic mineralization and adjacent pathology and verified by macro-examination. Retrospective review of the CBCT/MR images from 2 standing horses was also included. CBCT and FBCT identified...
Marichal G, Trigo P, Soto C, Meikle A, Suárez G.The Raid Uruguayo (RAID) is an equestrian endurance competition. This study characterized the hydroelectrolytic parameters (Na, K, Cl, tCa, and iCa), hematocrit (Ht), total plasma protein (TPP), and blood pH from 900 equine athletes (finishers and non-finishers) competing over distances of 80 to 115 km under different climate conditions. Paired blood samples were taken prior to the start of the competition (sample 1) and at the end of the race or at the time of leaving the competition (sample 2). The association of the comfort index (CI: low, moderate, and high) with blood parameters was evalu...
Acevedo HD, Hassebroek AM, Leventhal HR, Duhamel GE, Carvallo FR.A 17-y-old Rocky Mountain gelding was presented to the Virginia-Maryland Veterinary Teaching Hospital because of a 4-wk history of anorexia, weight loss, lethargy, and fever of unknown origin. Abdominal ultrasound revealed lymphadenomegaly of the abdominal and colonic lymph nodes, thickening of the wall of the large colon, and a mass associated with the large colon. The horse was euthanized given a poor prognosis. On autopsy, an ~20-cm diameter mass was found within the mesocolon between the right ventral and right dorsal colon. The mass had invaded through the colonic walls and formed a fistu...
Carver C, Bruemmer J, Coleman S, Landolt G, Hess T.Laminitis associated with equine metabolic syndrome causes significant economic losses in the equine industry. Diets high in non-structural carbohydrates (NSC) have been linked to insulin resistance and laminitis in horses. Nutrigenomic studies analyzing the interaction of diets high in NSCs and gene expression regulating endogenous microRNAs (miRNA) are rare. This study's objectives were to determine whether miRNAs from dietary corn can be detected in equine serum and muscle and its impacts on endogenous miRNA. Twelve mares were blocked by age, body condition score, and weight and assigned to...
Millis DL, Bergh A.Light therapy, or photobiomodulation, is a collective name for methods where tissue is irradiated with different types of light, with the aim of stimulating healing. Despite being frequently used, there is no consensus regarding the optimal treatment protocols for light therapy, nor its clinical efficacy. A systematic literature review was conducted, searching the relevant literature regarding light therapy in three databases, published between 1980-2020. The risk of bias in each article was evaluated. Forty-five articles met the inclusion criteria; 24 articles were regarding dogs, 1 was regar...
Siegers E, van den Broek J, Sloet van Oldruitenborgh-Oosterbaan M, Munsters C.Young Friesian stallions have to complete a 10-week training program (70-day test) for acceptance as a breeding stallion. Part one of this study showed that the 70-day test was too intense and led to reduced fitness. In the present (part two) study, the effects of an adapted training program were studied. Training frequency and minutes of cantering per week were lowered compared with part one. The external workload (EW) of sixteen stallions (3.4 ± 0.8 years) was monitored during the 6-weeks before testing (preparation period) as well as during the 70-day test. Standardized exercise tests (SET...
Gordon D, Clark-Price S, Keating S, Schaeffer DJ, Lascola KM.This study evaluated the effects of various flow rates and fractions of oxygen on arterial blood gas parameters and on the fraction of inspired oxygen (FO) delivered to the distal trachea. Oxygen was administered to 6 healthy, conscious, standing, adult horses via single nasal cannula positioned within the nasopharynx. Three flow rates (5, 15, 30 L/min) and fractions of oxygen (21, 50, 100%) were delivered for 15 minutes, each in a randomized order. FO was measured at the level of the nares and distal trachea. Adverse reactions were not observed with any flow rate. FO (nares and trachea) and P...
Runge KE, Bak M, Vestergaard A, Staerk-Østergaard J, Jacobsen S, Pihl TH.Predicting non-survival in horses with acute colitis improves early decision making. Therefore, this study aimed to determine the prognostic value of serum amyloid A (SAA) and other clinicopathological and clinical variables in adult horses with acute colitis. Clinical variables, SAA and other blood biomarkers, including plasma L-lactate (lactate), were assessed in 176 horses with acute colitis. A multivariate model for the prediction of non-survival was constructed. Icelandic horses were analysed separately. Admission SAA was similar in survivors (median 548 mg/L; range 0-5453 mg/L) and...
Baker E, Geick A, Hines M, Gerhold R, Cordero-Aponte C.A 17-year-old female grade pony presented to University of Tennessee Veterinary Medical Center in May of 2021 for evaluation of multifocal, firm, sessile, circular lesions of various diameters on the ventrum and flank. The lesions had been present for two weeks at presentation. An excisional biopsy found numerous adult and larval rhabditid nematodes most consistent with Halicephalobus gingivalis. PCR targeting a portion of the large ribosomal subunit confirmed this diagnosis. The patient was treated with a high dose course of ivermectin followed by fenbendazole. The patient began showing neuro...
Paraschou G, Vogel PE, Lee AM, Trawford RF, Priestnall SL.Multisystemic eosinophilic epitheliotropic disease (MEED) is a rare condition of equids characterized by eosinophilic infiltration of multiple organs. Clinical signs are variable depending on the affected organs. The most common clinical signs include chronic weight loss, diarrhoea and exfoliative dermatitis. Respiratory distress and raised liver enzymes are less frequently seen. The cause is unknown and the pathogenesis is poorly understood. There are less than 50 reported cases of horses with MEED. We now document the lesions in three donkeys with fluctuating or chronic loss of weight, letha...
You Y, Proctor RM, Haughan J, Missanelli JR, Robinson MA.Fentanyl, a powerful synthetic mu opioid receptor agonist, is banned in equine sports by the Association of Racing Commissioners International and the Fédération Équestre Internationale. The presence of fentanyl in equine blood has been confirmed during routine post-race screening for doping substances in the authors' laboratory. While fentanyl can be detected and confirmed in blood, it is rapidly metabolized, and screening for the metabolite N-[1-(2-phenethy-4-piperidinyl)] maloanilinic acid (PMA) in equine urine is expected to allow for a longer detection time. In this study, a quantitati...
Boisseau M, Mach N, Basiaga M, Kuzmina T, Laugier C, Sallé G.Equine strongyles encompass more than 64 species of nematode worms that are responsible for growth retardation and the death of animals. The factors underpinning variation in the structure of the equine strongyle community remain unknown. Methods: Using horse-based strongyle community data collected after horse deworming (48 horses in Poland, 197 horses in Ukraine), we regressed species richness and the Gini-Simpson index upon the horse's age, faecal egg count, sex and operation of origin. Using the Ukrainian observations, we applied a hierarchical diversity partitioning framework to estimate ...
Rohlf CM, Garcia TC, Fyhrie DP, le Jeune SS, Peterson ML, Stover SM.Mechanical properties of arena surfaces are extrinsic factors for musculoskeletal injury. Vertical impact forces of harrowed and compacted cushion were measured at five locations on 12 arena surfaces (five dirt, seven synthetic [dirt and fiber]). Eight variables related to impact force, displacement, and acceleration were calculated. Surface temperature, cushion depth and moisture content were also measured. The effects of surface material type (dirt/synthetic) and cushion compaction (harrowed/compacted) on vertical impact properties were assessed using an analysis of variance. Relationships o...
Curnow B, Rich AF, Ireland J, Correa DC, Dunn J, Jenkins D, Carslake H, Ressel L.Although the equine sarcoid is the most common skin neoplasm in domesticated horses, histopathological characteristics have not previously been evaluated for association with recurrence. The aim of this retrospective cohort study was to investigate clinical and histopathological features of excised equine sarcoids and to evaluate their association with recurrence at the original surgical site and at new sites. Clinical records and excisional biopsies from 106 equine sarcoids from 64 horses referred to Leahurst Equine Hospital, University of Liverpool, between March 2010 and February 2015 were ...
de Almeida Campos AC, Cicolo S, de Oliveira CM, Molina CV, Navas-Suárez PE, Dos Santos TP, da Silveira VB, Barbosa CM, Baccarin RYA, Durigon EL....No abstract available
Chans-Veres J, Albiñana-Cunningham J, Quintela JM, Pereira E, Tejero S.Surgery for severe equine cavo-varus is complex and must be individualized. The interindividual phenotypic variability demands a personalized planning of each foot to be operated. The study's primary goal was to evaluate the function and satisfaction of a series of patients with severe equinus cavo-varus deformity who underwent a triplanar tarsectomy and transposition of the posterior tibial tendon in a single stage surgery after a patient specific 3D biomodel planning. A series of 12 feet (5 patients bilaterally) operated with this technique was analyzed. The cohort comprised 2 females (28.5 ...
Pusterla N, Barnum S, Lawton K, Wademan C, Corbin R, Hodzic E.Contemporary data on equine herpesvirus-1 (EHV-1) genotype (non-neuropathogenic or N, neuropathogenic or D and new variant or H) in clinically diseased equids is important in order to determine the frequency of these genotypes and their association with disease expression. A total of 297 EHV-1 qPCR-positive swabs collected from 2019 to 2022 from horses with respiratory disease (EHV-1), neurological disease (equine herpesvirus-1 myeloencephalopathy [EHM]) and abortion were tested for the three different EHV-1 genotypes (N, D and H) using qPCR allelic discrimination assays. All submissions origi...
Jammes M, Contentin R, Cassé F, Galéra P.Osteoarthritis (OA) is a degenerative disease that eventually leads to the complete degradation of articular cartilage. Articular cartilage has limited intrinsic capacity for self-repair and, to date, there is no curative treatment for OA. Humans and horses have a similar articular cartilage and OA etiology. Thus, in the context of a One Health approach, progress in the treatment of equine OA can help improve horse health and can also constitute preclinical studies for human medicine. Furthermore, equine OA affects horse welfare and leads to significant financial losses in the equine industry....
Roxon C, Slack J, Bender S, Burns H, Turner R.A 12-year-old Standardbred stallion presented with a 5-month history of a growing mass in the left testis as well as an overall decrease in left testicular size. Palpation and ultrasonography of the left testis revealed a firm, hypoechoic, clearly delineated soft tissue mass in the craniolateral portion of the testis that measured 2.5 × 2.3 × 1.9 cm. Two smaller, hypoechoic regions also were visible ultrasonographically in the left testis, suggesting the presence of multifocal/multicentric neoplasia. The affected testis was very small (testicular volume of 40.3 cm). The right testis was ...
Bartolome Del Pino LE, Meana A, Zini M, Cersini A.Equine piroplasmosis (EP) is a vector borne disease caused by apicomplexans protists Babesia caballi (Nuttal et Strickland, 1910) and Theileria equi (Laveran, 1901). Carrier mares may transmit the infection transplacental resulting in neonatal piroplasmosis or abortions. This event has been described for T. equi by several authors over the world, but no evidence for B. caballi has been reported in Europe. In this study, vertical transmission for both parasites in an Italian breed mare has been confirmed using molecular and microscopic tools. Transplacental transmission is an underestimated pro...
Klecel W, Drobik-Czwarno W, Martyniuk E.Arabian show horses are well known for their exceptional beauty and elegance. The breed type, body conformation and movement are assessed during horse shows by licensed judges. The 5 judging categories are type, head and neck, body and topline, legs and movement, which are scored on a 20 point scale. It can be hypothesized that the scores in different categories are related to each other, and that the score for the most subjective type category depends on the scores for conformation categories. We analyzed 762 sets of average scores obtained by 583 unique horses at the World Championships. Cor...
Camargo Garbin L, Lopez C, Carmona JU.In the 1990s, the role of platelets in inflammation and tissue healing was finally recognized. Since then, the clinical use of platelet-derived products (hemocomponents), such as, platelet-rich plasma (PRP), markedly increased. The promise of a more economical option of a disease-modifying treatment led to the intensive and continuous research of PRP products and to its widespread clinical use. A number of protocols and commercial kits have been developed with the intention of creating a more practical and reliable option for clinical use in equine patients. Still, the direct comparison betwee...
Ocansey BK, Kosmidis C, Agyei M, Dorkenoo AM, Ayanlowo OO, Oladele RO, Darre T, Denning DW.Histoplasmosis is a chronic granulomatous disease caused by the thermally dimorphic fungus Histoplasma capsulatum. The 2 variants Histoplasma capsulatum var. capsulatum (Hcc) and Histoplasma capsulatum var. duboisii (Hcd) causes infection in humans and commonly termed classical or American histoplasmosis and African histoplasmosis, respectively. Histoplasma capsulatum var. farciminosum (Hcf) affects equines. In recent times, there have been heightened sensitization on fungal infections such as histoplasmosis in Africa, aimed at improving awareness among relevant stakeholders, particularly heal...
Garton NJ, Gilleron M, Brando T, Dan HH, Giguère S, Puzo G, Prescott JF, Sutcliffe IC.Rhodococcus equi is a major cause of foal morbidity and mortality. We have investigated the presence of lipoglycan in this organism as closely related bacteria, notably Mycobacterium tuberculosis, produce lipoarabinomannans (LAM) that may play multiple roles as virulence determinants. The lipoglycan was structurally characterized by gas chromatography-mass spectrometry following permethylation, capillary electrophoresis after chemical degradation, and (1)H and (31)P and two-dimensional heteronuclear nuclear magnetic resonance studies. Key structural features of the lipoglycan are a linear alph...
Wagnerová P, Sak B, McEvoy J, Rost M, Matysiak AP, Ježková J, Kváč M.Faecal samples were collected from 352 horses on 23 farms operating under six different management systems in the Czech Republic and Poland during 2011 and 2012. Farms were selected without previous knowledge of parasitological status. All faecal samples were screened for Cryptosporidium spp. presence using microscopy, following aniline-carbol-methyl violet staining and PCR analysis of the small-subunit (SSU) rRNA and the 60-kDa glycoprotein (gp60) genes. Cryptosporidium muris-positive samples were additionally genotyped at four minisatellite markers: MS1 (encoding a hypothetical protein), MS2...
David F, Farley J, Huang H, Lavoie JP, Laverty S.To evaluate mRNA expression of several proinflammatory and anti-inflammatory cytokines and chemokines in equine unstimulated and interleukin-1beta (IL-1beta)-stimulated chondrocytes. Methods: In vitro experiment using equine chondrocyte cultures. Methods: Whole articular cartilage from metacarpophalangeal joints (n=5 horses; 10 fetlocks). Methods: Chondrocyte monolayer cultures were established from digested adult equine articular cartilage and stimulated with 5 ng/mL of recombinant human IL-1beta. RNA was extracted from the cells 24 hours after stimulation. IL-1beta, IL-4, IL-6, IL-8, tumor n...
Maliye S, Voute LC, Marshall JF.This study aimed to quantify the compensatory response to naturally-occurring forelimb lameness on load redistribution. Data from lameness investigations using an inertial sensor based system to monitor the response to forelimb diagnostic anaesthesia were reviewed. Horses with primary forelimb lameness were grouped for analysis as (1) all horses combined (n= 28), (2) forelimb-only lameness (n= 8/28), (3) forelimb-contralateral hindlimb lameness (n= 14/28), (4) forelimb-ipsilateral hindlimb lameness (n= 6/28). The effect of diagnostic anaesthesia on measures of head and pelvic movement ...
Aurich C, Spergser J.This study investigated effects of bacteria from the genital tract of horses and the effect of gentamicin in semen extender on spermatozoal function in cooled-stored stallion semen. Semen was collected from healthy stallions and processed with a milk-based extender with or without gentamicin (1g/l). Pseudomonas (Ps.) aeruginosa, Staphylococcus (St.) aureus, Streptococcus (Sc.) equi subsp. equi (Sc. equi), Sc. equi subsp. zooepidemicus (Sc. zooepidemicus), Sc. dysgalactiae subsp. equisimilis (Sc. equisimilis) or culture medium alone (control) were added. Immediately after addition of bacteria a...
Edmunds DH, Whittaker DK, Green RM.The progress of artificial caries-like lesions created in human, bovine, equine, and ovine enamel has been studied. Lesions were produced by exposure to an acid gel system or by 5-day exposure to a sequential batch culture technique using Streptococcus mutans NCTC 10832. Longitudinal ground sections were prepared. The lesions were of similar appearance in all species when examined in polarized light. The depth in human enamel was approximately half that in the animal species. Microradiography confirmed subsurface demineralization in all four species. Similar depth ratios were seen in the scann...
Anderson JR, Phelan MM, Foddy L, Clegg PD, Peffers MJ.Osteoarthritis is an age-related degenerative musculoskeletal disease characterized by loss of articular cartilage, synovitis, and subchondral bone sclerosis. Osteoarthritis pathogenesis is yet to be fully elucidated with no osteoarthritis-specific biomarkers in clinical use. equine cartilage explants ( = 5) were incubated in tumor necrosis factor-α (TNF-α)/interleukin-1β (IL-1β)-supplemented culture media for 8 days, with the media removed and replaced at 2, 5, and 8 days. Acetonitrile metabolite extractions of 8 day cartilage explants and media samples at all time points underwent one-d...
Felkel S, Vogl C, Rigler D, Jagannathan V, Leeb T, Fries R, Neuditschko M, Rieder S, Velie B, Lindgren G, Rubin CJ, Schlötterer C, Rattei T, Brem G....Humans have shaped the population history of the horse ever since domestication about 5500 years ago. Comparative analyses of the Y chromosome can illuminate the paternal origin of modern horse breeds. This may also reveal different breeding strategies that led to the formation of extant breeds. Recently, a horse Y-chromosomal phylogeny of modern horses based on 1.46 Mb of the male-specific Y (MSY) was generated. We extended this dataset with 52 samples from five European, two American and seven Asian breeds. As in the previous study, almost all modern European horses fall into a crown group...
van Maanen C, Bruin G, de Boer-Luijtze E, Smolders G, de Boer GF.The purpose of the study was twofold. First, using two groups of 22 foals each, we investigated the extent to which maternal antibodies interfere with the humoral response against equine influenza. The foals were born to mares that had been vaccinated twice yearly against influenza since 1982. Foals of group I were vaccinated three times at early ages (12, 16, and 32 weeks of age), and foals of group II were likewise vaccinated but a later ages (24, 28, and 44 weeks of age). After the first and second vaccinations, neither group showed an increase in antibodies that inhibit haemagglutination. ...
Halbert ND, Reitzel RA, Martens RJ, Cohen ND.To evaluate sensitivity and specificity of a multiplex polymerase chain reaction (PCR) assay for simultaneous detection of Rhodococcus equi and differentiation of strains that contain the virulence-associated gene (vapA) from strains that do not. Methods: 187 isolates of R equi from equine and nonequine tissue and environmental specimens and 27 isolates of bacterial species genetically or morphologically similar to R equi. Methods: The multiplex PCR assay included 3 gene targets: a universal 311-bp bacterial 16S ribosomal RNA amplicon (positive internal control), a 959-bp R equi-specific targe...
Olomski F, Fettelschoss V, Jonsdottir S, Birkmann K, Thoms F, Marti E, Bachmann MF, Kündig TM, Fettelschoss-Gabriel A.Insect bite hypersensitivity (IBH) is the most common seasonal pruritic allergic dermatitis of horses occurring upon insect bites. In recent years, a major role for IL-31 in allergic pruritus of humans, monkeys, dogs, and mice was acknowledged. Here, we investigate the role of IL-31 in IBH of horses and developed a therapeutic vaccine against equine IL-31 (eIL-31). IL-31 levels were quantified in allergen-stimulated peripheral blood mononuclear cells (PBMCs) and skin punch biopsies of IBH lesions and healthy skin from IBH-affected and healthy horses. The vaccine consisted of eIL-31 covalently ...
Timoney PJ, McCollum WH, Murphy TW, Roberts AW, Willard JG, Carswell GD.The carrier state has been confirmed virologically in Thoroughbred and non-Thoroughbred stallions naturally infected with equine arteritis virus (EAV). Short-term or convalescent and long-term carriers occur. The frequency rate of the long-term carrier state in Thoroughbreds was high, averaging 33.9% among the three groups of stallions under study. While the convalescent carrier state only lasted a few weeks after clinical recovery, the long-term carrier state could persist for years. There was evidence, however, that not all such carriers might remain persistently infected for life. Carrier s...
Renshaw RW, Glaser AL, Van Campen H, Weiland F, Dubovi EJ.A virus that could not be identified as a previously known equine virus was isolated from the mononuclear cells of a horse. Electron microscopy revealed enveloped virions with nucleocapsid structures characteristic of viruses in the Paramyxoviridae family. The virus failed to hemabsorb chicken or guinea pig red blood cells and lacked neuraminidase activity. Two viral genes were isolated from a cDNA expression library. Multiple sequence alignments of one gene indicated an average identity of 45% as compared to Morbillivirus N protein sequences. A weaker relationship was found with Tupaia paramy...
Kim KH, Oang KY, Kim J, Lee JH, Kim Y, Ihee H.Here we report structural dynamics of equine myoglobin (Mb) in response to the CO photodissociation visualized by picosecond time-resolved X-ray solution scattering. The data clearly reveal new structural dynamics that occur in the timescale of ∼360 picoseconds (ps) and ∼9 nanoseconds (ns), which have not been clearly detected in previous studies.
Tecles F, Cerón JJ.Whole blood cholinesterase was measured using acetyl-, butyryl- and propionylthiocholine as substrates in 10 healthy adult dogs, cats, horses, pigs, goats, sheep and cows, in order to determine and characterise the cholinesterase activity in whole blood of the main domestic animals. An in vitro exposure test with two anticholinesterase compounds, the organophosphate insecticide coumaphos and the carbamate insecticide imidocarb, was also performed. In whole blood of ruminants and pigs, acetylthiocholine yielded the highest cholinesterase activity and other substrates were poorly hydrolysed; in ...
Rapoport A, Aharonson-Raz K, Berlin D, Tal S, Gottlieb Y, Klement E, Steinman A.Equine piroplasmosis imposes great concerns for the equine industry regarding international horse movement, and therefore requires reliable diagnostic tools. Recent studies from South Africa and Jordan, including a preliminary study in Israel, reported extremely low seroprevalence to Babesia caballi (B. caballi) (0-1%) using the acceptable rhoptry-associated protein-1 (RAP-1) cELISA. In accordance with the study from South Africa demonstrating a significant heterogeneity in the rap-1 gene sequence of South African B. caballi isolates, the objectives of this study were to phylogenetically chara...
Evans DL, Harris RC, Snow DH.At 2 and 5 mins after an 800-m gallop, venous blood was collected from 26 Thoroughbred racehorses for measurement of blood lactate concentration, packed cell volume (PCV) and haemoglobin concentration. In addition, 14 racehorses were given a strenuous submaximal treadmill exercise test. Heart rates during and after exercise at 10 m/sec on a treadmill inclined at 5 degrees were recorded. Blood samples at 2 and 5 mins after exercise were used to measure PCV, blood and plasma lactate and ammonia concentrations. Results of each exercise test were compared with the retrospective performance of hors...
de Laat MA, Sillence MN.Insulin dysregulation can be difficult to diagnose from basal insulin and glucose concentrations, so a field-based oral glucose test (OGT) is preferred. However, the repeatability of this test has not been reported. Objective: To determine the repeatability of an in-feed OGT in ponies and examine some factors affecting the palatability of the test meal. Methods: A repeated measures, longitudinal study. Methods: An in-feed OGT was performed at 08.00 h on 3 consecutive occasions under controlled conditions in 8 mixed breed ponies. d-glucose (0.75 g/kg bwt) was dissolved in water and combined wit...
Gilkerson JR, Bailey KE, Diaz-Méndez A, Hartley CA.Many viral agents have been associated with respiratory disease of the horse. The most important viral causes of respiratory disease in horses are equine influenza and the equine alphaherpesviruses. Agents such as equine viral arteritis virus, African horse sickness virus, and Hendra virus establish systemic infections. Clinical signs of disease resulting from infection with these agents can manifest as respiratory disease, but the respiratory tract is not the major body system affected by these viruses. Treatment of viral respiratory disease is generally limited to supportive therapies, where...
Xu Z, Kang X, Han P, Du P, Li L, Zheng A, Deng C, Qi J, Zhao X, Wang Q, Liu K, Gao GF.The origin and host range of SARS-CoV-2, the causative agent of coronavirus disease 2019 (COVID-19), are important scientific questions as they might provide insight into understanding of the potential future spillover to infect humans. Here, we tested the binding between equine angiotensin converting enzyme 2 (eqACE2) and the receptor binding domains (RBDs) of SARS-CoV, SARS-CoV-2 prototype (PT) and variant of concerns (VOCs), as well as their close relatives bat-origin coronavirus (CoV) RaTG13 and pangolin-origin CoVs GX/P2V/2017 and GD/1/2019. We also determined the crystal structures of eq...
Chaichanasiriwithaya W, Rikihisa Y, Yamamoto S, Reed S, Crawford TB, Perryman LE, Palmer GH.Ehrlichia risticii causes an acute infectious disease in horses called Potomac horse fever. To investigate the biological diversity of E. risticii organisms, nine E. risticii isolates derived from the peripheral blood monocytes of clinically sick horses in Ohio and Kentucky during the summers of 1991 and 1993 were compared with Illinois and Virginia isolates originally obtained from horses in Maryland in 1984. Seven of the nine isolates (081, 606, 380, 679, As, Co, and Ov) formed large morulae (tightly packed inclusions of ehrlichial organisms). The remaining isolates, including 1984 isolates,...
French NP, Smith J, Edwards GB, Proudman CJ.The reason for undertaking this study was that postoperative complications of colic surgery lead to patient discomfort, prolonged hospitalisation and increased cost. Potential risk factors for the 6 most common postoperative complications (jugular thrombosis, ileus, re-laparotomy, wound suppuration, incisional herniation and colic) were evaluated using multivariable models. Jugular thrombosis was associated significantly with heart rate greater than 60 beats/min and with increased packed cell volume (PCV) at admission. The risk of postoperative ileus also increased with increasing PCV at admis...
Weiland G.The increasing horse trade requires a reliable immunodiagnosis of equine piroplasma infections due to import restrictions imposed by various countries, including the United States of America. It was the aim of our investigations to establish the suitability of serological tests for the detection of parasite carriers and, eventually, to differentiate between Babesia caballi and B. equi infections. The investigations were carried out on 11 ponies with experimentally-induced B. caballi and/or B. equi infection. The infections were confirmed by the demonstration of parasites in blood smears 2-13 d...
Kumar S, Gupta AK, Pal Y, Dwivedi SK.The therapeutic efficacy of imidocarb, artesunate, arteether, buparvaquone and arteether+buparvaquone combination was evaluated against Babesia equi of Indian origin in splenectomised donkeys with experimentally induced acute infection. Efficacies of these drugs were tested by administering each drug or drug combination to groups of donkeys (having three donkeys each group). One group of donkey was kept as untreated control for comparing the results. Parasitaemia, haematology (WBC, RBC, PCV, granulocytes and haemoglobin), biochemical parameters (SAST, SALT, alkaline phosphatase, albumin/globul...
Hanggi EB, Ingersoll JF.Three horses (Equus caballus) with a history of performing cognitive tasks including discrimination learning, categorization, and concept use were tested to evaluate their long-term memory (LTM) in three experiments. In addition, use of LCD multi-displays for stimulus presentation was incorporated into cognition testing protocol for the first time with horses. Experiment 1 tested LTM for discrimination learning that originally occurred 6 years earlier. Five sets of stimuli were used and the two horses tested showed no decrement in performance on four of the sets; however, both horses did score...
Tripathi VN, Harding WC, Willingham-Lane JM, Hondalus MK.Rhodococcus equi is a facultative intracellular, Gram-positive, soilborne actinomycete which can cause severe pyogranulomatous pneumonia with abscessation in young horses (foals) and in immunocompromised people, such as persons with AIDS. All strains of R. equi isolated from foals and approximately a third isolated from humans contain a large, ~81-kb plasmid which is essential for the intramacrophage growth of the organism and for virulence in foals and murine in vivo model systems. We found that the entire virulence plasmid could be transferred from plasmid-containing strains of R. equi (dono...
Teifke JP, Kidney BA, Löhr CV, Yager JA.We examined 12 formalin-fixed paraffin-embedded feline skin tumours which had the histopathological features of fibropapillomas for the presence of papillomavirus (PV) DNA using touchdown polymerase chain reaction (PCR), DNA sequencing and nonradioactive in situ hybridization. Nine of the tumours contained a 102-bp PCR product demonstrated using consensus PV primers that amplify a portion of the L1 gene. The nucleotide sequences are closely related, but not identical to that of ovine PV type 2, rabbit oral PV and reindeer PV. The deduced amino acid sequences had strong homologies with the majo...
