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.
Sharma D, Gupta S, Sethi K, Kumar S, Kumar R.Trypanosoma evansi, a hemoflagellate protozoan parasite, causes wasting disease called surra in wide range of animals. Although the organism has been reported from various parts of India, data generated from organized epidemiological study is still in infancy in majority states of India. In the present study, livestock of Himachal Pradesh, India, was targeted for epidemiological investigation of T. evansi infections. A total of 440 equines and 444 cattle serum samples were collected from four agro-climatic zones. Furthermore, serum samples of 280 buffaloes from three different agro-climatic zo...
Van Crombrugge E, Vanbeylen E, Van Cleemput J, Van den Broeck W, Laval K, Nauwynck H.Respiratory disease in horses is caused by a multifactorial complex of infectious agents and environmental factors. An important pathogen in horses is equine herpesvirus type 1 (EHV-1). During co-evolution with this ancient alphaherpesvirus, the horse's respiratory tract has developed multiple antiviral barriers. However, these barriers can become compromised by environmental threats. Pollens and mycotoxins enhance mucosal susceptibility to EHV-1 by interrupting cell junctions, allowing the virus to reach its basolateral receptor. Whether bacterial toxins also play a role in this impairment ha...
Buhl R, Hesselkilde EM, Carstensen H, Hopster-Iversen C, van Loon G, Decloedt A, Van Steenkiste G, Marr CM, Reef VB, Schwarzwald CC, Mitchell KJ....The recurrence rate of atrial fibrillation (AF) in horses after cardioversion to sinus rhythm (SR) is relatively high. Atrial fibrillatory rate (AFR) derived from surface ECG is considered a biomarker for electrical remodelling and could potentially be used for the prediction of successful AF cardioversion and AF recurrence. Objective: Evaluate if AFR was associated with successful treatment and could predict AF recurrence in horses. Methods: Retrospective multicentre study. Methods: Electrocardiograms (ECG) from horses with persistent AF admitted for cardioversion with either medical treatmen...
Morris ERA, Wu J, Bordin AI, Lawhon SD, Cohen ND.Streptococcus equi subsp. (SEE) is a host-restricted equine pathogen considered to have evolved from Streptococcus equi subsp. (SEZ). SEZ is promiscuous in host range and is commonly recovered from horses as a commensal. Comparison of a single strain each of SEE and SEZ using whole-genome sequencing, supplemented by PCR of selected genes in additional SEE and SEZ strains, was used to characterize the evolution of SEE. But the known genetic variability of SEZ warrants comparison of the whole genomes of multiple SEE and SEZ strains. To fill this knowledge gap, we utilized whole-genome sequenci...
Schoen LM, Al Naem M, Röcken M, Geburek F.Lacerations of the axillary region occur frequently in horses. Typical complications caused by entrapment of air in the wound during locomotion are subcutaneous emphysema, with consecutive pneumomediastinum and pneumothorax. In this case report, the clinical, radiographic and laboratory diagnosis and management of these complications after an axillary laceration that finally resulted in pneumoperitoneum are described. A 1-year-old Hannoveranian was presented with a pre-existing axillary laceration of unknown duration and subcutaneous emphysema in the surrounding tissue. Due to extensive tissue...
Lanier CJ, Taintor JS, Christopherson PW, Spangler EA.Acidemia in sick or injured horses is often due to lactic acid accumulation. Alterations in platelet function and hemostasis are among numerous deleterious effects caused by decreased physiologic pH. Objective: We aimed to evaluate the effect of hyperlactatemia and resultant acidemia on platelet aggregation in equine whole blood using impedance aggregometry. Methods: Platelet aggregation was measured using the Multiplate analyzer in whole blood from 34 healthy horses at baseline and after in vitro addition of lactic acid to adjust the pH. Platelet aggregation of each sample was quantified by t...
Goto A, Tagami M, Kato F, Suzuki T, Yamaga T, Murase H, Sato F, Tsogtgerel M, Niikura T, Moriyama T, Chiba A, Watanabe KI, Tsuzuki N, Nambo Y.We performed a standing hand-assisted laparoscopic ovariectomy in a draft mare that presented with high serum anti-Müllerian hormone (AMH) level and had an enlarged single cystic ovary. Histopathological examination revealed no tumor cell proliferation in the ovary, but the presence of a large ovarian cyst was confirmed. In the diagnosis of abnormal ovaries in mares, a comprehensive assessment should be performed, including the monitoring of ovarian morphology and biomarkers over time, to determine the disease prognosis and treatment plan. The case of this mare with a nonneoplastic abnormal o...
Pye J, Spriet M, Dow P, Katzman S, Murphy BG.To describe clinical, imaging, gross, and histopathological abnormalities associated with osteochondral necrosis of the femoral condyles in foals and identify features suggestive of a common pathogenesis. 8 Thoroughbred foals euthanized with a presumptive diagnosis of necrosis of the femoral condyles. Postmortem CT was performed on all distal femoral epiphyseal samples. The articular epiphyseal cartilage complex (AECC) of affected distal femurs was examined grossly and histologically, focusing on lesions of interest identified on CT images. 7 foals were between 9 and 23 days old at the time of...
Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortazar Schmidt C, Herskin M, Michel V, Miranda Chueca MA....In this opinion, the antimicrobial-resistant bacteria responsible for transmissible diseases that constitute a threat to the health of horses have been assessed. The assessment has been performed following a methodology composed of information collected via an extensive literature review and expert judgement. Details on the methodology used for this assessment are explained in a separate opinion. A global state of play of antimicrobial-resistant spp. spp. and subsp and subsp. and subsp. has been provided. Among those bacteria, EFSA identified , and with more than 66% certainty as the mo...
Rumfola E, Banse HE, Atkins M, McGowan CM, Ireland JL.Endocrinopathic laminitis is the most common cause of laminitis in the field. Insulin has recently been implicated as a key factor in development of endocrinopathic laminitis; however, it is unclear whether diagnostic, and treatment approaches reflect insights derived from recent research. This study sought to evaluate North American veterinary practitioners' approach to endocrinopathic laminitis in the field. Demographic information, approach to diagnosis, management, and prognosis of endocrinopathic laminitis, as well as factors influencing changes in approach to laminitis were collected. To...
Loynachan AT.Pulmonary malformations are rare equine congenital anomalies. Over a 3-year timeframe, three cases of left sided pulmonary agenesis were diagnosed in perinatal foals. All three cases were associated with concurrent ipsilateral diaphragmatic herniation and hypoplasia of the right lung lobe. All three foals died immediately following parturition due to perinatal asphyxia associated with the congenital malformations. To the author's knowledge, this is the first report of pulmonary agenesis in the horse.
Lee H, Lee SH, Lee YR, Kim HY, Moon BY, Han JE, Rhee MH, Kwon OD, Kwak D.Enterocytozoon bieneusi is a microsporidian pathogen. Recently, the equestrian population is increasing in Korea. The horse-related zoonotic pathogens, including E. bieneusi, are concerns of public health. A total of 1,200 horse fecal samples were collected from riding centers and breeding farms in Jeju Island and inland areas. Of the fecal samples 15 (1.3%) were PCR positive for E. bieneusi. Interestingly, all positive samples came from Jeju Island. Diarrhea and infection in foals were related. Two genotypes (horse1, horse2) were identified as possible zoonotic groups requiring continuous mon...
Wernery U, Chan E, Raghavan R, Teng JLL, Syriac G, Siu SY, Joseph M, Yeung ML, Jia L, Cai JP, Chiu TH, Lau SKP, Woo PCY.Glanders is a highly contagious and potentially serious disease caused by Burkholderia mallei, a Tier 1 select agent. In this study, we raised a monoclonal antibody (mAb) against the lipopolysaccharide (LPS) of B. mallei and developed a competitive enzyme-linked immunosorbent assay (cELISA) for B. mallei infection. Using the titrated optimal conditions of B. mallei-LPS (2 ng) for microtiter plate coating, sample serum dilution at 1:20 and 3.5 ng/μL anti-LPS mAb B5, the cutoff value of the cELISA was determined using serum samples from 136 glanders-free seronegative horses in Hong Kong. All ca...
Grzyb J, Podstawski Z, Bulski K.Keeping horses in good condition requires providing them with living conditions that meet welfare requirements. These animals should be accommodated with suitable space, access to high nutritional fodder and water, and a suitable microclimate in their shelters. When it comes to the environment in the stables, a serious problem is created by particulate matter (PM), which consists of bacteria. PM concentration may be responsible for developing multiple lower respiratory tract diseases in horses, including allergies and recurrent airway obstruction (RAO). In turn, these ailments may lead to decr...
Temesgen T, Getachew Y, Negussie H.Equine herpesvirus (EHV) infections have major economic, health, and welfare impacts on equids. This study was performed in three selected zones of central Ethiopia with the objectives of detecting EHV-1, -2, and -5 in horses and donkeys with suggestive signs of respiratory tract disease and to assess epidemiological risk factors associated with infections. Methods: A total of 58 nasopharyngeal swab samples were collected from donkeys and horses showing clinical signs of respiratory disease. Polymerase chain reaction (PCR) was used to detect EHV-1, -2, and -5. Evaluation of the associated risk...
Deacon LJ, Navas de Solis C, Richardson DW, Polkes A, Reef VB.• An ACF developed in a hospitalized horse following orthopedic surgery. • Spontaneous closure of the ACF occurred 6 weeks after initial diagnosis. • Echocardiography is the primary imaging modality to confirm the presence of ACF in equids. [Figure: see text]
Rozario C, Martínez-Sobrido L, McSorley HJ, Chauché C.Influenza A viruses (IAVs) are important respiratory pathogens of horses and humans. Infected individuals develop typical respiratory disorders associated with the death of airway epithelial cells (AECs) in infected areas. Virulence and risk of secondary bacterial infections vary among IAV strains. The IAV non-structural proteins, NS1, PB1-F2, and PA-X are important virulence factors controlling AEC death and host immune responses to viral and bacterial infection. Polymorphism in these proteins impacts their function. Evidence from human and mouse studies indicates that upon IAV infection, the...
Abbas G, Ghafar A, Hurley J, Bauquier J, Beasley A, Wilkes EJA, Jacobson C, El-Hage C, Cudmore L, Carrigan P, Tennent-Brown B, Gauci CG, Nielsen MK....Cyathostomins are the most important and common parasitic nematodes of horses, with > 50 species known to occur worldwide. The frequent and indiscriminate use of anthelmintics has resulted in the development of anthelmintic resistance (AR) in horse nematodes. In this study we assessed the efficacy of commonly used anthelmintics against cyathostomins in Australian thoroughbred horses. Methods: Two drug efficacy trials per farm were conducted on two thoroughbred horse farms in the state of Victoria, Australia. In the first trial, the horses on Farm A were treated with single and combinations ...
Oliveira T, Santos A, Silva J, Trindade P, Yamada A, Jaramillo F, Silva L, Baccarin R.In humans, hospitalisation, disease type, and environmental factors evidently affect the quality of sleep, further influencing patient recovery. The objective of the present study was to report the resting and lying behaviour of hospitalised horses, and whether lying behaviours differ depending on the physiological severity of joint damage. We hypothesised that the resting and lying behaviour can change during the hospitalisation and physiological severity of joint damage affect the time of rest in horses. A descriptive observational study was performed to evaluate the effect of hospitalisatio...
Page AE, Partridge E, Erol E, Scoggin KE, Fedorka CE, Ruby RE, Ball BA, Horohov DW, Adam E.Cases of nocardioform placentitis are characterized by focal, mucoid placentitis resulting in late-term abortion, premature birth, or small, full-term foals, occur sporadically, and are most commonly associated with Crossiella equi and Amycolatopsis spp. infection. The goal of this project was to develop an enzyme-linked immunosorbent assay (ELISA) for quantifying antibodies against Crossiella equi and Amycolatopsis spp. and utilize the ELISA to determine when exposure occurs. Serum samples collected during the 2020 foaling season from Crossiella equi (n = 8) and Amycolatopsis spp. (n = 32...
Ayad A, Almarzook S, Besseboua O, Aissanou S, Piórkowska K, Musiał AD, Stefaniuk-Szmukier M, Ropka-Molik K.Genetic disorders in horses are mostly fatal or usually cause significant economic losses for breeders and owners. Here we studied a total of 177 Arabian, Barb and Arab-Barb horses from the Middle East and North Africa (MENA) using Sanger Sequencing and PCR-ACRS (polymerase chain reaction-artificially created restriction site) approaches to examine the genetic disorders in the studied horse breeds. We identified the genetic variations related to Cerebellar Abiotrophy (CA), Severe Combined Immunodeficiency (SCID) occurrence, and the studied population was free of the mutant allele determined La...
Scare Kenealy JA, Steuer AE.All horses are susceptible to the equine gastrointestinal parasite, Strongylus vulgaris, which is known to cause significant disease and death. The parasite undergoes development from the egg through the first (L1), second (L2) and third (L3) larval stages outside the horse. The L3 is the infective stage. The universally available technique for detection of S. vulgaris larvae is the larval culture method. This requires a 10-14 day culture period to induce development from egg to L3, followed by Baermannization and identification of the L3s to genus and/or species. It is unknown if the culture ...
Patterson Rosa L, Mallicote MF, MacKay RJ, Brooks SA.Macrolide drugs are the treatment of choice for infections, despite severe side-effects temporary anhidrosis as a. To better understand the molecular biology leading to macrolide induced anhidrosis, we performed skin biopsies and Quantitative Intradermal Terbutaline Sweat Tests (QITSTs) in six healthy pony-cross foals for three different timepoints during erythromycin administration-pre-treatment (baseline), during anhidrosis and post-recovery. RNA sequencing of biopsies followed by differential gene expression analysis compared both pre and post normal sweating timepoints to the erythromycin...
Mathis D, Sass JO, Graubner C, Schoster A.Atypical myopathy (AM), an acquired multiple acyl-CoA dehydrogenase deficiency (MADD) in horses, induce changes in mitochondrial metabolism. Only few veterinary laboratories offer diagnostic testing for this disease. Inborn and acquired MADD exist in humans, therefore determination of organic acids (OA) in urine and acylcarnitines (AC) in blood by assays available in medical laboratories can serve as AM diagnostics. The evolution of OA and AC profiles in surviving horses is unreported. Methods: AC profiles using electrospray ionization tandem mass spectrometry (ESI-MS/MS) and OA in urine using...
Erwin SJ, Blikslager AT, Ziegler AL.Colic is a leading cause of death in horses, with the most fatal form being strangulating obstruction which directly damages the intestinal barrier. Following surgical intervention, it is imperative that the intestinal barrier rapidly repairs to prevent translocation of gut bacteria and their products and ensure survival of the patient. Age-related disparities in survival have been noted in many species, including horses, humans, and pigs, with younger patients suffering poorer clinical outcomes. Maintenance and repair of the intestinal barrier is regulated by a complex mucosal microenvironmen...
Amado-Fuentes M, Gozalo M, Garcia-Gomez A, Barrios-Fernandez S.People with disabilities due to genetic origin often present high levels of stress: non-pharmacological interventions such as Equine-Assisted Interventions (EAI) may be a useful strategy. The objective of this pilot study was to evaluate stress levels in two participants with 22q11.2 deletion syndrome diagnosis, immediately after carrying out the EAI. A single case experimental design methodology was chosen due to the small sample size. Two participants with 22q11.2 Deletion Syndrome, a rare disease, with different comorbidities were included. The present study considered the EAI as the indepe...
Sakurai M, Isshiki S, Sasaki N, Sakai Y, Yamada Y, Morimoto M.A 7-year-old male Thoroughbred horse exhibited recurrent falls followed by convulsive seizures. The horse was clinically diagnosed with epilepsy and phenobarbital treatment was initiated. However, as seizure control was unsuccessful, the animal was euthanized. At necropsy, yellow-brown linear lesions were found extensively at the U-fibres and cingulate gyrus within the cerebral white matter. Histopathologically, linear demyelination and occasional cavitation were observed. Glial cells with yellow-brown pigment granules, which were autofluorescent, positive to the periodic acid-Schiff reaction ...
Suganuma K, Acosta TJ, Valinotti MFR, Sanchez AR, Mossaad E, Elata A, Inoue N.Despite the epidemic situation of animal trypanosomosis caused by Trypanosoma evansi, Trypanosoma equiperdum and Trypanosoma vivax in South American countries, there are no reports for the prevalence of animal trypanosomes in Paraguay. In this study, 408 blood samples were obtained from apparently healthy horses from sixteen departments of Paraguay, for routine medical check-up from August to September 2019, and a polymerase chain reaction (PCR)-based cross-sectional study was carried out to identify trypanosome prevalence. The prevalence of Trypanozoon (T. evansi and T. equiperdum) and T. viv...
Ryan A, Gurney M, Steinbacher R.A 10-year-old 466 kg mustang gelding presented to an equine referral hospital for surgical repair of nasal, frontal and lacrimal bone fractures from an unknown trauma. Surgical repair was performed under general anaesthesia, including a right-sided maxillary regional anaesthetic block with mepivacaine hydrochloride. Progressive hyperkalaemia was documented perianaesthetically (T-3 mins; 134 mins after induction; potassium 6.4 mmol/L (ref 3.5-5.1 mmol/L). Perianaesthetic bradycardia was attributed to alpha -2 agonist infusion administration, and other characteristic ECG changes (flattened ...
Franklin RP, Kinde H, Jay MT, Kramer LD, Green EG, Chiles RE, Ostlund E, Husted S, Smith J, Parker MD.A yearling quarter horse, which was raised in southern California, received routine vaccinations for prevention of infection by Eastern equine encephalomyelitis virus (EEEV). One week later, severe neurologic signs developed, and the horse was humanely destroyed. A vaccine-related encephalomyelitis was later suspected. A final diagnosis of EEEV infection was established on the basis of acute onset of the neurologic signs, histopathologic and serologic testing, and isolation and molecular characterization of EEEV from brain tissue. The vaccine was extensively tested for viral inactivation. Nucl...
Proudman CJ, Trees AJ.There is increasing interest in the application of serological methods to macro-parasite infections to indicate infection intensity, which in turn is related to pathogenicity. Colic is the single most important cause of mortality in horses and there is evidence that a proportion of colic cases are associated with infection with the intestinal cestode Anoplocephala perfoliata. In order to develop better tools to investigate this association, the correlation between antigen-specific equine IgG and IgG(T) and infection intensity of A. perfoliata was investigated. Affinity purification of a 12/13 ...
Olitsky PK, Harford CG.Young (12 to 15 day old) mice are approximately as susceptible to the virus of equine encephalomyelitis, Eastern or Western strain, when it is given intraperitoneally as are adult mice when the virus is injected intracerebrally. With this susceptibility by the intraperitoneal route as a basis, the injection of immune serum-virus mixtures intraperitoneally was found to result in protection in dilutions which give rise to infection after intracerebral inoculation. The difference of protective power by the two indicated routes was shown not to depend on the amount of inoculum nor on the age of th...
Tutluoglu B, Atiş S, Anakkaya AN, Altug E, Tosun GA, Yaman M.This study aimed to investigate the rate of occupational sensitization to horse hair in grooms and whether occupational exposure to horse hair increases respiratory and allergic symptoms and affects lung function in grooms or not. Methods: This is a cross-sectional study. Two hundred grooms were randomly selected among 1000 grooms working in Veliefendi Hippodrome of Istanbul. One hundred and twenty-five subjects agreed to enter the study. Ninety-two workers who worked in the different parts of this hippodrome enrolled as the control group. A detailed questionnaire including respiratory and all...
Won SY, Kim YC, Kim SK, Jeong BH.Prion diseases are fatal neurodegenerative diseases and are characterized by the accumulation of abnormal prion protein (PrP) in the brain. During the outbreak of the bovine spongiform encephalopathy (BSE) epidemic in the United Kingdom, prion diseases in several species were reported; however, horse prion disease has not been reported thus far. In previous studies, the shadow of prion protein (Sho) has contributed to an acceleration of conversion from normal prion protein (PrP) to PrP, and the shadow of prion protein gene () polymorphisms have been significantly associated with the susceptibi...
Meny P, Menéndez C, Ashfield N, Quintero J, Rios C, Iglesias T, Schelotto F, Varela G.Leptospirosis is important in Uruguay due to the economic loss caused by the diseases of production animals, mainly bovines, and also due to frequent human infection. We decided to study anti-Leptospira antibodies in the sera of dairy workers, rice laborers, veterinarians, suburban slum dwellers and garbage recyclers. Our aims were to estimate the seroprevalence of infection by Leptospira spp. in these people at risk, the relative importance of the known risk factors associated with infection, and the impact of human infections in each setting. Groups at risk were identified and 35 visits to t...
Leclere M, Costa MC.Gastrointestinal microbiota can be influenced by several factors, including diet and systemic inflammation, and in turn could act as a modulator of the allergic response. Fecal microbiota of horses with asthma has not been described. Objective: Analyze the bacterial fecal microbiota of horses with and without asthma under different environment and diet conditions, during both remission and exacerbation. Methods: Prospective observational study. Feces from 6 asthmatic and 6 healthy horses were collected under 3 different conditions: on pasture, housed indoors receiving good quality hay ("good h...
De Souza PN, Bomfim TC, Huber F, Abboud LC, Gomes RS.To detect Cryptosporidium sp., Giardia sp. and Eimeria leuckarti in horses, fecal samples were collected from three different handling horse groups from the state of Rio de Janeiro, Brazil. Group A was composed of "Mangalarga Marchador" pure breed horses, Group B was formed by horses of a Military Corporation and Group C by stray horses captured by the Center of Zoonosis Control Paulo Dacorso Filho. A total of 396 fecal samples were collected, 212 samples from Group A, 154 samples from Group B and 30 from Group C. The material was submitted to the centrifugation - flotation technique and stain...
Livesay GJ, O'Neill T, Hannant D, Yadav MP, Mumford JA.In July 1989 influenza A/equine-2 (H3N8) was isolated from a nasopharyngeal swab taken from a non-thoroughbred horse exhibiting acute clinical respiratory disease. This was the first isolation of equine influenza virus in the United Kingdom since 1981. Subsequent investigations of acute respiratory disease in horses indicated that the infection was dispersed throughout the UK. However, unlike the previous epidemic of 1979, the first horses from which the virus was isolated had been vaccinated. This outbreak of influenza provided an opportunity to evaluate an antigen capture ELISA, directed aga...
Varcasia A, Garippa G, Pipia AP, Scala A, Brianti E, Giannetto S, Battelli G, Poglayen G, Micagni G.Between March 2003 and February 2007, the livers and the lungs of 2,231 horses from various Italian regions were examined for cystic echinococcosis presence at the time of slaughter. Hydatid cysts were found in six horses, namely four from Sardinia, one from Sicily, and one from Tuscany. The location, number, morphology, and fertility of the cysts found were determined. DNA was extracted from the germinal layers and protoscoleces of the fertile cysts and polymerase chain reactions (PCR) were performed in order to strain type DNA isolates for reduced nicotinamide adenine dinucleotide dehydrogen...
Laabassi F, Lecouturier F, Amelot G, Gaudaire D, Mamache B, Laugier C, Legrand L, Zientara S, Hans A.An outbreak of equine influenza (EI) was reported in Algeria between May and July, 2011. The outbreak started in Tiaret, in west province of Algeria, and spread to the other parts of the country affecting almost 900 horses in many provinces. The population studied was composed of 325 horses from different groups of age. Clinical sign expression was age dependent. Indeed, a morbidity rate of 14.9% was observed in horses under 15 months old and a rate of 4.95% in horses over 8 years old. Interestingly, the morbidity rate raised sharply to reach 100% in horses aged between 18 months and 7 yea...
Schaefer E, Harms C, Viner M, Barnum S, Pusterla N.Equine coronavirus (ECoV) is a recently reported enteric disease of adult horses. Natural infection by ECoV has been reported in adult horses worldwide, whereas experimental infection has only been reported in juvenile horses. An experimental infection model is needed to study the clinical presentation, laboratory abnormalities, and pathophysiological changes associated with ECoV. Objective: To investigate the clinical, hematologic, molecular, and serological features of adult horses experimentally infected with ECoV. Methods: Eight adult horses. Methods: Four horses were intragastrically infe...
Martinez M, Modric S.In veterinary medicine, the characterization of a drug's pharmacokinetic (PK) properties is generally based upon data that are derived from studies that employ small groups of young healthy animals, often of a single breed. These are also the data from which population predictions are often generated to forecast drug exposure characteristics in the target population under clinical conditions of use. In veterinary medicine, it is rare to find information on the covariates that can influence drug exposure characteristics. Therefore, it is important to recognize some of the factors that can alter...
Brault SA, Bird BH, Balasuriya UB, MacLachlan NJ.Equine herpesvirus-2 (EHV-2) infection has been implicated as a cause of a variety of clinical disorders in young horses, including upper respiratory tract disease, generalized malaise, fever, pharyngeal lymphoid hyperplasia, and lymphadenopathy. Considerable sequence heterogeneity has been demonstrated previously among EHV-2 strains, and individual horses can be concurrently infected with more than one virus strain. In this study, the temporal variation of the viral load and genomic diversity of the glycoprotein B (gB) gene of EHV-2 in the nasal secretions of a cohort of foals was characteriz...
Shnaiderman-Torban A, Navon-Venezia S, Dor Z, Paitan Y, Arielly H, Ahmad WA, Kelmer G, Fulde M, Steinman A. We aimed to investigate the prevalence, molecular characteristics and risk factors of extended-spectrum β-lactamase (ESBL)-producing (ESBL-E) shedding in horses. A prospective study included three cohorts: (i) farm horses (13 farms, n = 192); (ii) on hospital admission (n = 168) and; (iii) horses hospitalized for ≥72 h re-sampled from cohort (ii) (n = 86). Enriched rectal swabs were plated, ESBL-production was confirmed (Clinical and Laboratory Standards Institute (CLSI)) and genes were identified (polymerase chain reaction (PCR)). Identification and antibiotic susceptibility were determi...
Wormstrand B, Østevik L, Ekman S, Olstad K.Failure of the cartilage canal blood supply leads to ischemic chondronecrosis which causes osteochondrosis, and osteochondral lesions. Osteochondrosis is a disease with a heritable component and usually occurs under aseptic conditions. Because bacteria can bind to growth cartilage and disrupt the blood supply in pigs and chickens, we considered whether this might play a role in development of equine osteochondrosis. The aim of this study was to examine whether bacteria are present in canals in the growth cartilage of foals with septic arthritis/osteomyelitis, and whether this is associated wit...
Macias Rioseco M, Beingesser J, Uzal FA.Clostridium perfringens type C causes necrotizing enteritis mostly in neonatal animals of several species, including horses. The virulence of C. perfringens type C is mostly mediated by beta toxin (CPB). This toxin is highly sensitive to the action of trypsin and other proteases, which explains the increased susceptibility of neonatal animals to type C infections. Final confirmation of type C disease diagnosis should be based on detection of CPB in the intestinal content of affected animals. However, because CPB is so sensitive to the action of proteases, it is believed that this toxin persist...
Stewart AJ, Hinchcliff KW, Saville WJ, Jose-Cunilleras E, Hardy J, Kohn CW, Reed SM, Kowalski JJ.Medical records of 101 blood culture-confirmed bacteremic foals were reviewed to determine whether foals with Actinobacillus sp. bacteremia are affected at an earlier age, have more severe signs of disease, and have a worse prognosis than do foals with bacteremia of other causes. Thirty percent (30/101) of bacteremic foals had Actinobacillus sp. cultured, and these were 2 times more likely to die (crude odds ratio [OR(CR)] 0.8, 4; P = .14), with a survival rate of 43% (13/30) compared to the overall survival rate of 55% (56/101). When compared to other bacteremic foals, foals with actinobacill...
Rehbein S, Lindner T, Visser M, Winter R.Faecal samples of 250 horses from farms with a known history of tapeworm infection were examined comparatively for cestode eggs using a double centrifugation/combined sedimentation-floatation technique. From each faecal sample, three 5 g and three 15 g subsamples were processed, each using either saturated NaCl solution, specific gravity (sp. g.) 1.2 [NaCl]; concentrated sugar solution, sp. g. 1.26 [sugar]; or concentrated ZnSO4 solution, sp. g. 1.3 [ZnSO4] for floatation. In total, faeces from 187 horses ( = 74.8%) tested 'positive' for Anoplocephala eggs. Percentages of samples testing '...
Verheyen KL, Henley WE, Price JS, Wood JL.Dorsometacarpal disease (DMD) is common in young Thoroughbred (TB) racehorses, often interfering with their training programme. No reports exist on incidence rate or associated risk factors in the UK. Objective: To estimate the incidence rate of DMD in TB horses in training for flat racing in the UK and identify associated risk factors, particularly in relation to training regimens. Methods: Data were drawn from a large prospective study in which TB horses in 13 training yards were monitored for a period of up to 2 years, recording daily training information and details of musculoskeletal inju...
Rott R, Herzog S, Richt J, Stitz L.Borna disease is an endemic progressive encephalomyelitis of horses and sheep prevalent in central Europe. A wide variety of animal species, ranging from chickens to primates can be infected experimentally with the causative virus, which is only poorly characterized. Furthermore, BD virus-specific antibodies have been detected in sera and cerebrospinal fluids of psychiatric patients. Our studies on the pathogenesis of BD have shown that-at least in rats-the disease is not caused by the infecting virus itself, but by a virus-induced immunopathological reaction. Thus, after intracerebral infecti...
KAPLAN MM, PAYNE AM.In 1957 the World Health Organization arranged a survey of horse and swine sera in a number of countries in order to gain information on the role and importance of animals in the epidemiology of influenza. The veterinary services of the countries concerned were requested to obtain blood specimens from these animals, if possible both before and after the human pandemic of Asian influenza. This paper reports on the results of haemagglutination-inhibition and complement-fixation tests performed on these sera in WHO Influenza Centres and other collaborating laboratories.It is apparent from these r...
Bracher V, Mathias S, Allen WR.Placentation between 80 and 220 days of gestation was studied by measurement of fetal dimensions and gross, light and transmission and scanning electron microscopic examinations of the allantochorion and endometrium from 4 fertile mares with no, or very mild, endometrial histopathology and 6 subfertile Thoroughbred mares suffering varying degrees of age-related chronic degenerative endometritis (endometrosis). Spontaneously occurring twin gestation was observed in 3 animals. Several of the subfertile mares had endometrial cysts which showed 2 distinct features during pregnancy: those located n...
Jakubek EB, Lundén A, Uggla A.Sera from 414 Swedish horses were investigated for the presence of antibodies to Toxoplasma gondii and Neospora sp. by the T. gondii direct agglutination test (DAT), and an Neospora caninum iscom-ELISA. Five sera (1%) had a titre >1:40 in DAT, but when analysed by immunoblotting against T. gondii antigens only two of them were positive, giving a seroprevalence of 0.5%. Since the Neospora iscom ELISA had not been validated for equine sera it was used for an initial screening, and all sera with an optical density exceeding 0.200 absorbance units were selected for further investigation by immu...
East LM, Savage CJ, Traub-Dargatz JL, Dickinson CE, Ellis RP.To identify clinical signs, physical examination findings, results of diagnostic tests, treatments administered, and clinical outcome of neonatal foals with enterocolitis associated with Clostridium perfringens infection. Methods: Retrospective study. Methods: 54 neonatal foals. Results: Most foals had acute onset of obtunded mentation, colic, or diarrhea and developed leukopenia, neutropenia, an abnormally high number of band neutrophils, toxic WBC, and hypoproteinemia within 24 hours after admission, despite high serum IgG concentrations (> 800 mg/dl). Abdominocentesis and abdominal radiogra...
ter Laak EA, Fennema G, Jaartsveld FH.Contagious Equine Metritis (CEM) was detected in the Netherlands for the first time in 1987. A total number of five mares (Dutch saddle-horse) were infected in three separate outbreaks. The origin of the infection could not be determined in any of the cases. As the isolates of the causal organism, Taylorella equigenitalis, showed auto-agglutination, diagnosis was difficult. Therefore, an indirect immune fluorescence test as used to diagnose the second isolate. Five strains were isolated, which all were resistant to streptomycin. The prevalence of CEM since 1981 is summarised. The importance of...
Sairanen J, Nivola K, Katila T, Virtala AM, Ojala M.The Finnish mating records of Standardbred trotters (SB; n = 33 679) and Finnhorses (FH; n = 32 731) were analysed to study the effect of the level of inbreeding on foaling rates and to estimate the heritability of foaling rate. A linear mixed model was assumed, with the outcome of the foaling (foal or no foal) as the trait of the study. A restricted maximum likelihood-based method was used to calculate the estimates of the variance components. Predictions of breeding values and estimates of fixed effects were also calculated. The average level of inbreeding was 9.9% in the SB and 3.6% in the ...
Coleman SU, Klei TR, French DD, Chapman MR, Corstvet RE.In 1985, 22 pony foals reared in a helminth-free environment were tested daily for oocysts of Cryptosporidium sp by use of fecal flotation. Oocysts were found in all foals. Oocysts were first observed in feces collected from foals 9 to 28 days after birth. The mean period of oocyst shedding was 10 days and ranged from 2 to 18 days in individual foals. Diarrhea was observed in 14 of 22 (64%) foals and began before the period of oocyst shedding. Fecal samples also were examined for other infective agents. Salmonella poona was isolated from 1 foal that did not have diarrhea, and coronavirus parti...
Lambert JL, Fernandez NJ, Roy MF.Band cells and toxic neutrophils are thought to indicate acute and severe systemic illness but no studies have investigated their importance in adult equine emergency admissions. Objective: The objective of this study was to evaluate the association of band cells and toxic neutrophils with systemic inflammatory response syndrome (SIRS) and outcome in horses. Methods: One hundred and five adult horses admitted on emergency basis to a private primary referral practice. Methods: Prospective observational study with sample collection. All horses admitted on emergency basis over the study period we...
Nielsen CF, Reisen WK, Armijos MV, Maclachlan NJ, Scott TW.Although horse cases frequently are reported during West Nile virus (WNV) outbreaks, few investigations have focused on the epidemiology of this transmission. From April to October 2003 to 2005, mosquito abundance and infection were monitored 3 days per week at an equine research facility at the University of California, Davis. Thirty-two nonvaccinated horses enrolled as controls in a vaccine study were bled monthly, and their serum was tested for evidence of WNV infection by plaque reduction neutralization test (PRNT). In 2004, one positive Culex pipiens pool was associated with a single hors...
