Disease management in horses encompasses the strategies and practices employed to prevent, control, and treat diseases affecting equine populations. This field involves understanding the etiology, transmission, and clinical presentation of various equine diseases, as well as implementing biosecurity measures and therapeutic interventions. Common diseases in horses include equine influenza, strangles, and equine herpesvirus. Effective disease management relies on accurate diagnosis, vaccination protocols, and the use of antimicrobials and other treatments. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, challenges, and advancements in managing diseases in equine health.
Abd El Kader NA, Farghali HA, Abu-Seida AM, Salem NY, Khattab MS.Early detection of cystitis in equine is essential to improve the prognosis and outcome of therapy. However, the conventional white light endoscopy is not sufficiently accurate for this purpose. Hence, this study evaluated chromoendoscopy as a recent diagnostic tool for cystitis in female donkeys. For this purpose, 5 apparently normal donkeys (control group) and 5 female donkeys with cystitis (diseased group) were used. Physical and rectal examinations, urine analysis, white light cystoscopy, methylene blue-based chromoendoscopy and histopathology were performed in all animals. Turbid urine ex...
Scare JA, Steuer AE, Gravatte HS, Kálmán C, Ramires L, Dias de Castro LL, Norris JK, Miller F, Camargo F, Lawyer A, De Pedro P, Jolly B, Nielsen MK.Anthelmintic resistance among cyathostomin parasites is a wide-spread problem. The parasite control guidelines written by the American Association of Equine Practitioners (AAEP) encourages the preservation of anthelmintic efficacy by reducing treatment frequency, using targeted deworming, and implementing environmental management practices. While there is knowledge regarding parasite management practices of affluent horse farms in the United States, surveys rarely explore the rural and underserved regions. The purpose of this study was to observe the management practices of horse farms in rura...
van der Kolk JH, Endimiani A, Graubner C, Gerber V, Perreten V.Acinetobacter spp. are aerobic, rod-shaped, Gram-negative bacteria belonging to the Moraxellaceae family of the class Gammaproteobacteria and are considered ubiquitous organisms. Among them, Acinetobacter baumannii is the most clinically significant species with an extraordinary ability to accumulate antimicrobial resistance and to survive in the hospital environment. Recent reports indicate that A. baumannii has also evolved into a veterinary nosocomial pathogen. Although Acinetobacter spp. can be identified to species level using matrix-assisted laser desorption/ionisation time-of-flight mas...
Seeber PA, Quintard B, Sicks F, Dehnhard M, Greenwood AD, Franz M.Equine Herpesviruses (EHV) are common and often latent pathogens of equids which can cause fatalities when transmitted to non-equids. Stress and elevated glucocorticoids have been associated with EHV reactivation in domestic horses, but little is known about the correlation between stress and viral reactivation in wild equids. We investigated the effect of an environmental stressor (social group restructuring following a translocation event) on EHV reactivation in captive Grévy's zebras (). A mare was translocated by road transport from Zoo Mulhouse, France, to join a resident group of three ...
Bedenice D, Johnson AL.EPM, CVSM, and EDM are currently recognized as the 3 most common neurologic diseases in US horses, with the latter 2 conditions being most prevalent in young animals. Moreover, horses competing at shows and performance events are at greater risk for exposure to highly contagious, neurologic EHV-1 outbreaks. A clinical diagnosis of any neurologic disease should be based on a careful history, complete neurologic examination, and appropriate diagnostic testing and interpretation. However, mild or early neurologic signs can often mimic or be mistaken for an orthopedic condition when horses present...
Salas-Romero J, Gómez-Cabrera KA, Salas JE, Vázquez R, Arenal A, Nielsen MK.Anthelmintic resistance in equine cyathostomins has been described worldwide, with resistance to the benzimidazole class being particularly widespread. The status of anthelmintic efficacy in Cuba has been virtually unknown due to the lack of equine labelled products. One recent report documented suboptimal efficacy levels of extra-label albendazole products against cyathostomins, but it remains unknown to which extent benzimidazole resistance exists in the population. The aim of the present study was to evaluate the anthelmintic efficacy of two benzimidazole products labelled for equines, fenb...
Fraser RS, Arroyo LG, Meyer A, Lillie BN.Collagenous lectins are a family of soluble pattern recognition receptors that play an important role in innate immune resistance to infectious disease. Through recognition of carbohydrate motifs on the surface of pathogens, some collagenous lectins can activate the lectin pathway of complement, providing an effective means of host defense. Genetic polymorphisms in collagenous lectins have been shown in several species to predispose animals to a variety of infectious diseases. Infectious diseases are an important cause of morbidity in horses, however little is known regarding the role of equin...
Nielsen MK, Branan MA, Wiedenheft AM, Digianantonio R, Scare JA, Bellaw JL, Garber LP, Kopral CA, Phillippi-Taylor AM, Traub-Dargatz JL.Equine strongyle parasites are ubiquitous in grazing equids across the world. Anthelmintic resistance is widely developed in cyathostomin populations, but very few surveys have evaluated anthelmintic efficacy in equine populations in the United States, and most of these are over 15 years old. The present study was carried out as part of the National Animal Health Monitoring Systems (NAHMS) Equine 2015-2016 study. The aims were to investigate anthelmintic treatment efficacy by means of the fecal egg count reduction test (FECRT) and identify parameters associated with decreased efficacy. Data we...
Becher AM, van Doorn DC, Pfister K, Kaplan RM, Reist M, Nielsen MK.Experts recommend a change in the control of equine parasites across the world in order to adopt a surveillance-based approach utilizing parasite faecal egg counts (FEC). Several European countries have implemented prescription-only restrictions of anthelmintic usage by law, which is in stark contrast to US, where all anthelmintic products continue to be available over the counter. This study aimed to describe and compare equine parasite control strategies employed in Germany, Austria, the Netherlands, US, and Denmark. An invitation to participate in an online questionnaire survey was publishe...
Elelu N.Tick-borne relapsing fever (TBRF) caused by the bacteria Borrelia, is poorly documented in veterinary medicine. Given the widespread presence of the soft tick vectors - Ornithodoros and the recently discovered hard tick vectors, as well as their close association with animal hosts, it is highly likely that infection occurs, but is rarely reported to be of veterinary importance. Sporadic reports of canine infection, some being fatal through to probable cause of abortion in horses have been published. Some of these pathogens exist in regions where there are limited diagnostic facilities, hence, ...
Clarke DL.Chondromalacia of the tracheal and bronchial cartilages and redundancy of the dorsal tracheal membrane result in collapse of the large airways, leading to coughing and airway obstruction. It most commonly affects small-breed dogs, although larger-breed dogs, cats, and miniature horses are also sporadically reported. Dynamic airway imaging is used to confirm the diagnosis. The primary goal of medical management is to control clinical signs attributable to coughing and airway inflammation. When this is no longer effective, tracheal stents provide a minimally invasive, rapid way to restore airway...
Guardabassi L, Apley M, Olsen JE, Toutain PL, Weese S.Optimization of antimicrobial treatment is a cornerstone in the fight against antimicrobial resistance. Various national and international authorities and professional veterinary and farming associations have released generic guidelines on prudent antimicrobial use in animals. However, these generic guidelines need to be translated into a set of animal species- and disease-specific practice recommendations. This article focuses on prevention of antimicrobial resistance and its complex relationship with treatment efficacy, highlighting key situations where the current antimicrobial drug product...
, and of the equine influenza group at the Animal Health Trust provide a timely reminder of risk of equine influenza and the importance of vaccination.
Tadros EM, Fowlie JG, Refsal KR, Marteniuk J, Schott HC.Hyperinsulinaemia is the suspected component of insulin dysregulation having the strongest association with laminitis and occurs variably in equids with pituitary pars intermedia dysfunction (PPID). Objective: We hypothesised that magnitude of hyperinsulinaemia correlates with laminitis severity in PPID-affected equids. Furthermore, we hypothesised that owners can be unaware of chronic endocrinopathic laminitis. Methods: Cross-sectional study. Methods: Serum insulin concentrations, owner-reported laminitis history and radiographic evidence of laminitis were determined in 38 client-owned horses...
Warnakulasooriya DN, Marth CD, McLeod JA, Hanlon DW, Krekeler N.Retained fetal membranes (RFM) is a common post-partum problem in mares for which the treatment is highly variable. The aim of this study was (i) to investigate the different treatments used by equine practitioners for RFM and (ii) to determine if there is a difference between treatments used by reproductive specialists and general equine practitioners. Information regarding treatment of RFM was sought from veterinary practitioners via a survey and this was compared to recommendations in the current literature. The survey was sent out to equine veterinarians and mixed practitioners with a high...
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...
Arroyo LG, Gomez DE, Martins C.Duodenitis-proximal jejunitis (DPJ) is an inflammatory process of the proximal part of the small intestine and occurs sporadically in horses. It is clinically characterized by an acute onset of ileus and nasogastric reflux leading to systemic signs of toxemia. This review discusses the definition of the disease, potential etiologic agents, clinical findings, epidemiological features, histopathologic and clinico-pathological findings, and medical management of this condition. spp., mycotoxins, and have all been associated with the disease but there is limited supporting evidence for any agen...
Nemoto M, Yamanaka T, Bannai H, Tsujimura K, Ueno T, Mekata H, Yoshida A, Koyama A, Kokado H.This study compared agar gel immunodiffusion (AGID) protocols for diagnosing equine infectious anemia. Two commercial testing kits were used: one following the Japanese Act on Domestic Animal Infectious Diseases Control and one following the World Organisation for Animal Health (OIE) manual. From 651 samples tested, both protocols gave identical results for 647 samples (23 samples tested positive; 624 tested negative). Non-specific reactions were observed in 21 samples testing negative by the Japanese protocol, but none were observed with the OIE protocol. The kappa coefficient value was 0.962...
Palomero AM, Hernández JA, Cazapal-Monteiro CF, Balán FA, Silva MI, Paz-Silva A, Sánchez-Andrade R, Vázquez MSA.The integrated control of strongyles was assayed for a period of three years in wild equids (zebras, European donkeys, and African wild asses) captive in a zoo and infected by strongyles. During three years control of parasites consisted of deworming with ivermectin + praziquantel; equids also received every two days commercial nutritional pellets containing a blend of 10 - 10 spores of the fungi + per kg meal. Coprological analyses were done monthly to establish the counts of eggs of strongyles per gram of feces (EPG). The reductions in the fecal egg counts (FECR) and in the positive horses...
Secombe CJ, Bailey SR, de Laat MA, Hughes KJ, Stewart AJ, Sonis JM, Tan R.The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.
Forteau L, Dumont B, Sallé G, Bigot G, Fleurance G.Strongyle infection is an important issue in horse breeding. It impairs horse health and performance, with young horses being the most sensitive. Strongyle control has long relied on the systematic use of chemical treatments. However, expanding anthelmintic resistance among strongyles calls for alternative options. Mixed grazing is assumed to reduce strongyle load on the pasture as the result of a dilution effect. This has been shown in small ruminants grazing with cattle, but the putative benefits of co-grazing between horses and cattle have not yet been evaluated. Here, we conducted field su...
Lyons ET, Tolliver SC, Drudge JH, Collins SS, Swerczek TW.Research on benzimidazole-resistant Population S small strongyles began in a Shetland pony herd in 1974 at the University of Kentucky and has continued for over 25 years. The present update, for the period 1992-1999, evaluated activity of pyrantel pamoate (PRT) in field tests in the pony herd. Additional critical tests with PRT and oxibendazole (OBZ) were done in foals born in the herd. Activity of PRT was initially excellent in field tests, based on epg/lpg count data, but declined rapidly during the second full year of pyrantel treatments. Critical test data for small strongyles indicated ef...
Grewar JD.Bluetongue (BT) and African horse sickness (AHS) are considered the most important orbiviral diseases in Southern Africans countries. The general endemic status makes these diseases challenging to be quanti ed in terms of their economic impact. Using country reported data from BT and AHS outbreaks and cases, as well as international trade data, the economic impact of BT and AHS is evaluated on local, regional, and global scales. Local scale impact in the Southern African region is underestimated as shown by the underreporting of BT and AHS. Exceptions occur during epidemic cycles of the diseas...
Tydén E, Skarin M, Andersson-Franko M, Sjöblom M, Höglund J.Anthelmintic resistance (AR) to macrocyclic lactones (ML) has been described in Parascaris of horses world-wide. In contrast, benzimidazoles (BZ) are still effective, although reduced efficacy to this drug class was recently reported. The mode of action of BZ is binding to β-tubulin, which prevents polymerisation of microtubules. In this study, β-tubulin gene expression of isotypes 1 and 2 was investigated at seven time points (0, 6, 24, 72, 96 and 120 h) during embryogenesis and in adult worms. In addition, an in ovo larval developmental test was developed to study β-tubulin gene expressio...
Agius CT, Studdert MJ.This chapter describes the molecular and biological properties of equine herpesviruses (EHV)2 and EHV5. It highlights advances in the study of EHV2 and EHV5. The reclassification of EHV2 and EHV5 as gammaherpesviruses rather than betaherpesviruses has profound implications for future approaches to the study of the two equine herpesviruses. The chapter places emphasis on a comparison between the properties of EHV2 and EHV5 and those of other gammaherpesviruses, especially Epstein-Barr virus (EBV), which is the causative agent of infectious mononucleosis/glandular fever in humans. Studies of the...
Afify AF, Hassanien RT, El Naggar RF, Rohaim MA, Munir M.Equid herpesviruses (EHVs) are a group of highly impactful viral pathogens that affect horses, presenting a substantial risk to the global equine industry. Among these, equid herpesvirus-1 (EHV-1) primarily causes respiratory infections. However, its ability to spread to distant organs can lead to severe consequences such as abortion and neurological diseases. These viruses can enter a dormant phase, with minimal activity, and later reactivate to trigger active infections at any time. Recently, there has been a notable rise in the prevalence of a particularly devastating strains of EHV-1 known...
Zhou B, Yang G, Hu Z, Chen K, Guo W, Wang X, Du C.Equine piroplasmosis (EP) is a parasitic disease caused by (), () and (). This disease is considered to be reportable by the World Organization for Animal Health (WOAH). Real-time quantitative PCR (qPCR) is regarded as a straightforward, rapid and sensitive diagnostic method to detect pathogens. However, qPCR has not been employed in the various epidemiological investigations of . In this study, we developed a new qPCR method to detect based on the chr1sco (chromosome 1 single-copy open reading frame (ORF)) gene, which has no detectable orthologs in or A TaqMan MGB probe was used in the ...
Thomson GR, Mumford JA, Spooner PR, Burrows R, Powell DG.Equine influenza type 2 infections occurred in the Newmarket areas in January 1976. The disease did not spread to any extent and while this may have been due to recent vaccination it was found that not all vaccinated horses were fully protected. The virus involved showed some antigenic drift from the prototype strain A/equine/Miami/1/63 (Heq 2 Neq 2).
Rendle DI, Duz M, Beech J, Parkin T, Durham AE.Paired measurement of ACTH concentration may be more reliable than a single measurement. Objective: To determine whether the mean of 2 measurements of ACTH concentration is more reliable in assessing pituitary pars intermedia dysfunction (PPID) than a single measurement. Methods: Paired ACTH measurements were performed on (1) 148 occasions from 124 horses being investigated for PPID, (2) 90 occasions from 76 horses with PPID that were receiving treatment with pergolide, and (3) 63 occasions from 50 horses in which there was no clinical suspicion of PPID. Histologic examination of the pars inte...
Daly JM, Newton JR, Wood JL, Park AW.Mathematical modelling of infectious disease is increasingly regarded as an important tool in the development of disease prevention and control measures. This article brings together key findings from various modelling studies conducted over the past 10 years that are of relevance to those on the front line of the battle against equine influenza.
Wang X, Wise JC, Stewart AJ.Hendra virus (HeV) emerged as a zoonotic pathogen in the 1990s, causing low morbidity but high mortality in humans and horses. Pteropid bats are the natural reservoir of HeV and other important zoonotic viruses such as Nipah and Ebola viruses. Equivac HeV, manufactured by Zoetis (Parkville, Victoria, Australia), is the only commercially available vaccine for horses. There is no commercial vaccine for humans. The epidemiology, clinical features, pathology, diagnosis, management, and prevention of HeV will be reviewed.
Kuwano A, Katayama Y, Kasashima Y, Okada K, Reilly JD.In horses with chronic laminitis, an abnormal horny structure called lamellar wedge, is generated between the hoof wall and the laminar epidermis. To be able to manage horses with chronic laminitis correctly, more information about the pathological state of this abnormal horn is required. The aim of this study was to collect and analyze objective morphological data about the abnormal horn in order to understand its morphology and development. In the study, the abnormal horn was grossly visible on the sagittal hoof section from approximately 20 days after the onset of disease. In the histologic...
Yiğin A.The extensive use of antibacterial agents used for treatment in human and veterinary clinics to increase yield in livestock and aquaculture in developing countries causes the detection and spread of multidrug-resistant (MDR) strains in different sources. The presence of Escherichia coli strains is very common in racehorses and it's a serious problem on horse farms. Extended-spectrum beta-lactamase (ESBL) production is an important source of MDR development in Gram-negative strains such as E.coli. This study aimed to detect the presence of ESBL genes in E. coli strains isolated from horse farms...
Lyons E.Population-S small strongyles have been studied since 1974 in central Kentucky in a closed Shetland pony breeding herd. The ponies were treated approximately every 8 weeks with cambendazole (1974-1978), oxibendazole (OBZ) (1978-1992), or pyrantel pamoate (PRT) (1992-1999). Small strongyles in the ponies have shown resistance to these compounds in field and critical tests. One purpose of this presentation was to compare different parameters for determination of effects on the small strongyle species in ponies after treatment, mainly with OBZ or PRT, from data in critical tests (n=112). Also, th...
Bellaw JL, Pagan J, Cadell S, Phethean E, Donecker JM, Nielsen MK.Parasitic helminths of equids are capable of causing ill-thrift, clinical disease, and death. Although young horses are the most susceptible to parasitic disease and are the most intensively treated cohort, deworming regimens are rarely evaluated within this age group. This study objectively evaluated the impact of deworming regimen on fecal egg counts (FECs), growth rates, and body-condition scores in young Thoroughbreds. Forty-eight Thoroughbred foals from three central Kentucky farms were randomly allocated to two treatment groups: an interval dose program receiving bi-monthly rotations of ...
Macpherson ML, Reimer JM.Twin pregnancy in the mare causes economic loss. Early transrectal ultrasonographic detection of twins and manual crush of one embryonic vesicle is the method of choice for managing equine twins (90% success rate). Transcutaneous and transvaginal ultrasound-guided twin reduction techniques are described for twin pregnancies that advance beyond 25 days of gestation. Reported success rates for the ultrasound-guided procedures are 50% and 20%, respectively.
Wang M, Guo W, Igarashi I, Xuan X, Wang X, Xiang W, Jia H.The objective of this study is to investigate the seroprevalence of equine piroplasmosis in China. A total of 1990 sera were collected from clinically healthy horses in various districts located in ten different provinces of China and examined by using indirect enzyme-linked immunosorbent assays (ELISAs) with recombinant Theileria equi (T. equi) merozoite antigen 2 (rEMA-2) and Babesia caballi (B. caballi) 48-kDa rhoptry protein (rBc48), respectively. The results showed that 1,018 (51.16%) and 229 (11.51%) samples were positive for B. caballi and T. equi infection, respectively. The number of ...
Marsella R, White S, Fadok VA, Wilson D, Mueller R, Outerbridge C, Rosenkrantz W.Allergic skin diseases are common in horses worldwide. The most common causes are insect bites and environmental allergens. Objective: To review the current literature and provide consensus on pathogenesis, diagnosis, treatment and prevention. Methods: The authors reviewed the literature up to November 2022. Results were presented at North America Veterinary Dermatology Forum (2021) and European Veterinary Dermatology Congress (2021). The report was available to member organisations of the World Association for Veterinary Dermatology for feedback. Conclusions: Insect bite hypersensitivity (IBH...
Joó K, Trúzsi RL, Kálmán CZ, Ács V, Jakab S, Bába A, Nielsen MK.In Hungary, equine parasite control is mostly based on traditional approaches involving rotational anthelmintic treatment at regular intervals. Almost no farms utilize fecal egg counts (FECs) on a regular basis to guide deworming treatments. This approach is certainly not sustainable and is the major factor responsible for the current high levels of anthelmintic resistance. The aims of this study were to statistically analyze risk factors associated with strongylid egg count magnitude and prevalence. Fecal samples and horse data (age, pasture history, stocking density, anthelmintic history) we...
Petersen MB, Tolver A, Husted L, Tølbøll TH, Pihl TH.The objective of this study was to investigate the prognostic value of single and repeated measurements of blood l-lactate (Lac) and ionised calcium (iCa) concentrations, packed cell volume (PCV) and plasma total protein (TP) concentration in horses with acute colitis. A total of 66 adult horses admitted with acute colitis (<24 h) to a referral hospital in the 2002-2011 period were included. The prognostic value of Lac, iCa, PCV and TP recorded at admission and 6 h post admission was analysed with univariate analysis, logistic regression, classification and regression trees, as well as ran...
Cullinane A, Gahan J, Walsh C, Nemoto M, Entenfellner J, Olguin-Perglione C, Garvey M, Huang Fu TQ, Venner M, Yamanaka T, Barrandeguy M, Fernandez CJ.To facilitate the temporary importation of horses for competition and racing purposes, with a minimum risk of transmitting equine influenza, the World Organisation for Animal Health (Office International des Epizooties, or OIE), formally engaged in a public-private partnership with the Federation Equestre Internationale (FEI) and the International Federation for Horseracing Authorities (IFHA) to establish, within the context of existing OIE standards, a science-based rationale to identify the ideal time period for equine influenza vaccination prior to shipment. Field trials using vaccines base...
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...
Bender JB, Tsukayama DT.Infectious agents are insidious, often changing to adapt to host defenses or treatment advances. Because these challenges will continue, the need to apply standard and transmission-based precautions is important not only in the human hospital setting but in the veterinary clinic setting. In addition, to prevent human infection and potential liability, clinics need to establish program algorithms to prevent disease spread for specific agents or planned procedures to respond to potential nosocomial and zoonotic disease events. These need to be done proactively. Furthermore, more money needs to b...
Tirosh-Levy S, Gottlieb Y, Mazuz ML, Savitsky I, Steinman A.The tick-borne equine hemoparasite, Theileria equi, is endemic in many parts of the world where prevalence may be high, and most infected horses are apparently healthy but serve as life-long carriers. To determine the factors that affect T. equi dynamics, we followed parasitic loads in apparently healthy horses at four time points during one year. A total of 1094 blood samples were collected from 395 horses, along with ticks and demographic and clinical data. Infection and load of T. equi were tested by PCR and qPCR, and for the spring dataset, infection was also tested serologically by IFAT (...
Chotel F, Parot R, Durand JM, Garnier E, Hodgkinson I, Bérard J.The choice of first-line treatment for congenital varus equine clubfoot remains a controversial issue largely dependent on experience. In France, functional treatment predominates. In 1948, Ponseti proposed reducing the deformity with successive casts. Although cast treatment is a very old method, Ponseti's method is original because it is based on strict rules established from anatomic evidence. The goal is not to correct the apparent deformation, but on the contrary to impose a simultaneous supination and abduction of the foot. Once the calcaneopedal block has been derotated, percutaneous te...
