Respiratory disease in horses encompasses a range of conditions affecting the respiratory system, including the upper and lower airways. These diseases can result from various etiologies such as infectious agents, environmental factors, or genetic predispositions. Common respiratory conditions in horses include equine asthma, equine influenza, and strangles. Clinical signs often associated with respiratory disease in horses include coughing, nasal discharge, and labored breathing. Diagnostic approaches may involve endoscopy, imaging, and laboratory tests to assess the function and health of the respiratory tract. This page compiles peer-reviewed research studies and scholarly articles that explore the pathophysiology, diagnosis, and management of respiratory diseases in equine populations.
Hall LQ, Senior JE, Walker RG. A technique involving thoracotomy for the implantation of polythene catheters through the left atrium into the pulmonary veins has been used in 2 ponies. In both animals the catheters enabled blood samples to be obtained from the pulmonary veins for more than 5 weeks. Post mortem examination after termination of the experiment showed the procedure and catheters produced the minimum of adverse effects.
Sholty KA, Hecobian A, Sullivan AP, Collett JL, Koch DW, Hackett ES.To evaluate plume composition during simulated diode laser equine upper airway surgery. Unassigned: A 980-nm diode laser fiber was applied in continuous-wave mode in contact with laryngeal and pharyngeal tissues of 6 equine cadaver heads, and resultant plumes were collected for analysis. Measured parameters included the real-time concentration of particulate matter under the size of 2.5 μm (PM2.5), organic carbon (OC), elemental carbon (EC), and volatile organic compounds (VOCs). Unassigned: Visible smoke was encountered during surgical laser application and plume collection. Diode laser medi...
Barbazanges P, Couroucé A, Le Digarcher G, Cardwell JM, Schmitt E, Toquet MP, Lemonnier LC, Richard EA.Fungi are ubiquitous in horses' environment. Their contribution to the pathophysiology of severe asthma (SA) is acknowledged, while controversies remain for mild-moderate asthma (MA). Objective: We hypothesised that fungi are a risk factor for asthma. Our objective was to compare different combinations of analytical methods (cytology, culture) and sampling sites (tracheal wash (TW), bronchoalveolar lavage fluid (BALF)) in relation to clinical status (control, MA, SA). Methods: Prospective cross-sectional study. Methods: The study population included asymptomatic racing horses in the field and ...
Fegraeus K, Riihimäki M, Nordlund J, Akula S, Wernersson S, Raine A.Single-cell RNA sequencing (scRNA-seq) is a valuable tool for investigating cellular heterogeneity in diseases such as equine asthma (EA). This study evaluates the HIVE™ scRNA-seq method, a pico-well-based technology, for processing bronchoalveolar lavage (BAL) cells from horses with EA. The HIVE method offers practical advantages, including compatibility with both field and clinical settings, as well as a gentle workflow suited for handling sensitive cells. Our results show that the major cell types in equine BAL were successfully identified; however, the proportions of T cells and macropha...
Rossi HS, Mykkänen AK, Junnila JJT, Hyytiäinen HK.Pulse oximetry has not been thoroughly evaluated for assessment of oxygenation in conscious foals. Compared with invasive arterial blood sampling, it is a painless and non-invasive method for real-time monitoring of blood oxygen saturation. The aim of this prospective clinical study was to evaluate the usability, validity, and reliability of pulse oximetry at two measuring sites (lip and caudal abdominal skin fold) for blood oxygen saturation measurement in conscious foals with and without respiratory compromise. Thirty-two foals under one month of age were used. Nineteen foals had normal resp...
Larson MA, Credille BC, Berghaus LJ, Papich MG, Beasley EM.To investigate the disposition of enrofloxacin and its active metabolite, ciprofloxacin, in plasma, pulmonary epithelial lining fluid (PELF), peritoneal fluid, and CSF in horses following IV administration of enrofloxacin at doses of 5 mg/kg and 7.5 mg/kg of body weight. Unassigned: 6 healthy, mature mares were randomly assigned to receive a single dose of enrofloxacin at either 5 mg/kg or 7.5 mg/kg in a crossover design with a washout period of 10 days. Concentrations of enrofloxacin and ciprofloxacin were determined in plasma, PELF, peritoneal fluid, and CSF. Unassigned: Both doses of enrofl...
Hardwick JL, Ahern BJ, Crawford KL, Allen KJ, Anderson BH, Rose KJ, Franklin SH.The relationship between Thoroughbred yearling laryngeal function (YLF) grade and race performance is unclear. Objective: To determine the effect of YLF on future race performance. Methods: Retrospective cohort study. Methods: Post-sale endoscopic recordings were reviewed from Australian yearling sales in 2018-2019. Race performance was evaluated for career and as 2-, 3- and ≥4-year-olds. Multivariable generalised linear modelling examined the association between YLF and performance, with risk estimates presented as coefficients (95% CI). Results: The YLF in 5175 examinations was graded I in...
Simões BP, Cerri FM, Takahira RK, Borges AS, Oliveira-Filho JP, Amorim RM.Chlorfenapyr is a pesticide that interferes with mitochondrial function, leading to cell death and mortality. Although poisoning is primarily documented in humans and dogs, it can result in severe clinical signs, including sweating, respiratory distress, and neurological dysfunction. This report describes the clinical and laboratory findings of a horse with suspected accidental intoxication with chlorfenapyr. A 4-year-old Quarter Horse mare was referred to the veterinary hospital with signs of excessive sweating, hyperthermia, tachypnea, muscle fasciculation, and fearful facial expression. The...
Wright CA, Lawton K, Barnum S, Craig BW, Farwell BR, Blea J, McCook C, Pusterla N.This study aimed to determine if exercise increases the frequency of selected respiratory viruses/bacteria shedding in non-clinical horses using nose wipes. Nose wipes were taken pre- and post- exercise from 133 healthy horses of various ages and disciplines. Wipes were assayed for the presence of selected common (equine herpesvirus-1 (EHV), EHV-4, S. equi spp equi) and commensal (EHV-2, EHV-5, S. equi spp zooepidemicus) respiratory pathogens. The frequency of detection increased significantly (p < 0.05) in the post-exercise wipes for EHV-1, EHV-2, EHV-5, and S. zooepidemicus. EHV-4 and S. equ...
Nowicka B, Polkowska I, Zeliszewska-Duk P, Torres A, Duk M.Similarly, in humans and horses, thoracic and lumbosacral back pain cause more disability and work interruptions worldwide than any other disease. Given that there are few effective treatments for back pain in humans and animals, primary prevention strategies and a reduction in pain factors may be crucial. In the analysed data obtained for the horses studied, the pattern of changes in adipocytokine concentrations, including resistin, visfatin and leptin, was noted for those with back pain compared to the control animals. Concentrations of selected adipocytokines in horses from the back pain gr...
Sanz MG, Jellen G, Cody L, Bergsma J, Cha M, Kogan C, Kordas G, Bayly WM, Leguillette R.Mild-moderate asthma is common in horses. Inhaled ciclesonide has been approved only for treatment of severe asthma in horses. Objective: We hypothesized that a 10-day treatment course of inhaled ciclesonide (Aservo EquiHaler) would improve clinical signs, endoscopic tracheal mucus scores, and bronchoalveolar lavage fluid (BALF) cytology in racehorses with moderate asthma. Methods: Racehorses with moderate asthma housed at the Emerald Downs Racetrack in Auburn, WA. Methods: Prospective, randomized, double-blinded, placebo-controlled clinical study. Horses received inhaled ciclesonide (n = ...
Parente A, Geburek F, Kästner S, Iversen C, Hopster K.Orotracheal intubation is commonly performed for inhalation anaesthesia in horses to ensure safe and reliable administration of volatile anaesthetics and to secure the airways. In human and equine medicine, the occurrence of intubation-associated complications has been described, which can range from mild mucosal irritation to severe necrosis. However, there are only sparse descriptions of mucosal alterations and the course of healing after elective surgery in horses. Objective: To investigate the prevalence and severity of tracheal lesions following endotracheal intubation associated with gen...
Hordle T, Ranninger E, Bettschart-Wolfensberger R.A 24 year old warmblood mare (case 1) and a 12 year old Holsteiner gelding (case 2) were anaesthetized for bursoscopy and phacoemulsification, respectively. Both were premedicated with intramuscular acepromazine (30 μg kg-1). The horses were sedated with intravenous (IV) medetomidine (7-9 μg kg-1 to effect), before anaesthetic induction with ketamine-diazepam. Anaesthesia was maintained with isoflurane in a mixture of oxygen and medical air, alongside a medetomidine constant rate infusion at 3.5 μg kg-1 hour-1. In recovery, 3 and 5 μg kg-1 of medetomidine were administered IV to cases 1 an...
May A, Riley CB, Scharre A, Zablotski Y, Padalino B.Equine road transport is stressful and associated with an increased risk of behavioral problems, injuries, respiratory and gastrointestinal diseases. This cross-sectional survey-based study aimed to describe transport-related practices and the perception of behavioral and health issues in Germany. The survey targeted horse owners (amateurs and professionals) and obtained demographic details, the participant's experience, frequency and duration of transportation, and behavioral and health problems related to equine transportation. Associations among behavioral and health problems and transport ...
Hansen S, Otten ND, Ceron JJ, González-Arostegui LG, Peres-Rubio C.The contribution of redox imbalance to equine asthma (EA) pathogenesis remains unclear. Objective: (1) validate and measure a panel of redox biomarkers in the tracheal wash (TW) and bronchoalveolar lavage (BAL) samples from horses with neutrophilic and mastocytic mild-moderate EA (MEA) and severe EA. (2) Evaluate the same panel in saliva and serum for comparative purposes. Methods: A total of 117 horses: 37 healthy, 26 mastocytic MEA, 29 neutrophilic MEA, and 25 severe EA. Methods: Cross-sectional study using TW, BAL, and serum and saliva sampling. After assay validation, redox biomarkers-ferr...
Barnett TP, Colgate VA, Robinson N, Smith LCR, Palmer L, Barakzai SZ.To compare overground endoscopy (OGE) findings and racing performance in horses before and after laryngeal tie-forward (LTF) surgery for the treatment of intermittent dorsal displacement of the soft palate (iDDSP). Methods: Retrospective case series with follow up. Methods: A total of 56 horses met the inclusion criteria. Methods: Clinical record review of all horses definitively diagnosed with iDDSP, treated with LTF surgery, and evaluated with a single OGE examination postoperatively. In addition to LTF, some horses underwent bilateral aryepiglottic fold resection (AEFR) and/or soft palate t...
Kawanishi N, Kinoshita Y, Reedy SE, Garvey M, Kambayashi Y, Bannai H, Tsujimura K, Yamanaka T, Cullinane A, Chambers TM, Nemoto M.Equine influenza virus (EIV) is one of the most important pathogens causing respiratory signs in equids. Rapid antigen detection (RAD) kits are useful for point-of-care testing because they are user-friendly and provide fast results. Although sensitive and broad-reactive RAD kits are needed for controlling horse movement, no RAD kits specified for EIV are available. Objective: This study evaluated the usefulness of seven RAD kits originally developed for human influenza and available in Japan during 2023-2024 for EIV antigen detection. Methods: Experimental assay comparison. Methods: The detec...
Pusterla N, Lawton K, Barnum S, Magdesian KG.In recent years, the use of non-invasive host and environmental samples for the detection and monitoring of equine respiratory pathogens has shown promise and a high overall agreement with the gold standard of nasal secretions. The present study looked at comparing nose wipes, stall sponges, and air samples with nasal swabs collected from 27 horses involved in an equine influenza (EI) outbreak. The outbreak involved 5 clinical, 6 subclinical, and 16 uninfected horses. Samples sets were collected at the onset of the index case and retested every 2-3 days thereafter until all horses tested qPCR-...
Munerato MS, Simon O, Nicholson A.This report describes successful cardiopulmonary resuscitation of a healthy, 525 kg, 8 years 9 months-old Quarter horse gelding. After successful pelvic limb orthopaedic surgery to excise a metatarsal bone under general anaesthesia, with the horse in left lateral recumbency, the horse was hoisted into recovery. After the horse was positioned in recovery, a routine cardiac check by thoracic auscultation was performed. Cardiopulmonary arrest (CPA) was identified by absence of cardiac sounds and pulse, as evaluated by digital palpation of the facial artery, absence of the right palpebral reflex, ...
Conley HE, Davis KU, Adler KB, Lavoie JP, Sheats MK.Asthma is a chronic inflammatory airway disease that affects millions of people worldwide. Horses develop asthma spontaneously and serve as a relevant model for multiple phenotypes and endotypes of human asthma. In horses with equine asthma (EA), environmental organic dust triggers increased inflammatory cytokines, excess airway mucus, reversible bronchoconstriction, and airway inflammation. In horses with severe EA (sEA), lower airway inflammation is invariably neutrophilic, making sEA a potential model for severe neutrophilic asthma in humans. Alveolar macrophages (AM) and airway neutrophils...
Jimenez C, Hogan P, Belaghi R, Curtiss A.Epiglottitis is an uncommon upper airway pathology manifested endoscopically by mucosal oedema, reddening and thickening of the epiglottic mucosa. Literature on epiglottitis in horses is sparse. Objective: To describe the diagnosis, treatment and outcome of Thoroughbred and Standardbred racehorses diagnosed with epiglottitis at a single centre. A secondary objective is to demonstrate the efficacy of inhaled and topical anti-inflammatories for this condition. Methods: Retrospective case series. Methods: Medical records (2009-2023) were reviewed for racehorses treated for epiglottitis. Data coll...
Himmele M, Engl JPM, Schwarz BC.The present report describes an 8-week-old warmblood foal presented following two episodes of epistaxis. The foal had a history of an umbilical infection, which had been treated with antibiotics when it was 8 days old. Four days before admission the filly showed severe, self-limiting epistaxis. The second hemorrhage occurred on the day of admission. The foal was lethargic and the remainder of the clinical examination unremarkable. A latero-lateral radiograph of the head revealed a fluid line within the guttural pouch. Endoscopy showed large amounts of blood within the pharynx and the upper thi...
James K, Chappell DE, Craig B, Pariseau C, Wright C, van Harreveld P, Barnum S, Pusterla N.The purpose of this study was to determine any associations of EHV-2, EHV-5, and dual infection with EHV-2/-5 with demographic parameters, clinical signs, and coinfection with other common respiratory pathogens. Nasal swabs collected from 9737 horses were tested for EHV-2 and EHV-5, as well as EHV-1, EHV-4, EIV, , ERAV, and ERBV, by qPCR. Clinical signs and demographic parameters were recorded, and prevalence factors were evaluated for significance regarding EHV-2 and/or EHV-5 infection. Out of the 9737 horses in this study, 17.8% tested EHV-2-positive ( = 1731), 15.8% tested EHV-5-positive ( ...
Legere RM, Ott JA, Poveda C, Vanover D, Borba KER, Yeon Joo J, Martin CL, da Silveira BP, Bray JM, Landrock K, Wright GA, Blazier JC, Hillhouse AE....Inhalation of Rhodococcus equi causes severe pneumonia in humans and animals worldwide, most commonly affecting horse foals. The standard for preventing R. equi pneumonia in foals is transfusion of hyperimmune plasma, which is expensive and carries the risk of adverse effects. Our goal was to passively immunize foals against R. equi by nebulizing mRNA encoding an equine monoclonal antibody (mAb) against the virulence-associated protein A (VapA) directly into the lungs. VapA-specific memory B cells from an immunized horse were used to identify and select the sequence for an equine immunoglobuli...
Mellish M, Burns J, Elce Y, Stull JW.Donkeys (Equus asinus) in East Africa are recognised as working with poorly designed harnesses and carts. The donkey cart used in regions of Africa, specifically Meru County, Kenya, appears to place the cart's weight solely on the donkey's mid-cervical region. The ventral area of the neck is vulnerable to external pressure on the trachea, which is superficially located. Objective: To compare the presence and severity of endoscopic abnormalities in the upper airway and trachea of Meru County working cart donkeys compared to pack donkeys. To determine associations between endoscopic and physical...
Rossi HS, Mykkänen AK, Teppo AM, Junnila JJT, Hyytiäinen HK.Pneumonia is a common condition in young, hospitalized foals, causing accumulation of inflammatory secretions to the airways. In humans, respiratory physiotherapy is commonly used as a supplementary treatment for pneumonia with varying results regarding its efficacy, but the efficacy in foals has not been assessed to date. Objective: This study aimed to evaluate the safety and efficacy of respiratory physiotherapy as a supplementary therapy method for young foals with pneumonia. Methods: A total of 44 foals with pneumonia aged under a month were used. The prospective intervention group receivi...
Strand E, Vermedal H, Olsen HMB, Fjordbakk CT, Fretheim-Kelly ZL.Clinical evaluation of alar fold (AF) collapse is presently based upon subjective evaluation of improvement in breathing and respiratory noise after suturing the AFs dorsally. Objective: To evaluate use of nasopharyngeal airway pressure (NAP) as an objective method of assessing for the presence of AF collapse during exercise. NAPs should also potentially provide a precise means to grade the degree of airway obstruction present and response to surgical treatment. Methods: Prospective clinical study of actively racing Standardbred horses. Methods: Standardbreds undergoing this test were outfitte...
Albornoz A, Morales B, Fernandez VB, Henriquez C, Quiroga J, Alarcón P, Moran G, Burgos RA.Equine asthma is a chronic respiratory disease characterised by neutrophilic inflammation, airway hyperresponsiveness, and impaired pulmonary function. Obesity, increasingly prevalent among domestic horses, has been identified as a potential risk factor for exacerbating inflammatory conditions. This study aimed to explore whether obesity modifies neutrophil metabolism and inflammatory responses in horses affected by asthma. Six asthmatic horses in clinical remission were categorised into two groups: obese and non-obese, based on body condition score. Serum levels of interleukin-1β (IL-1β) an...
Hildebrandt D, Venner M, Hart KA, Berghaus L.Early and specific diagnosis of bronchopneumonia in foals is important to prevent severe disease. In human medicine, C-reactive protein (CRP) and interleukin-6 (IL-6) are important diagnostic and prognostic biomarkers in neonatal pneumonia in other species. Evaluation of these markers in foals with naturally occurring respiratory diseases is lacking. Objective: To determine if CRP and IL-6 were useful predictors of respiratory disease in foals from birth to weaning. Methods: Prospective cohort study. Methods: Periodic blood samples from 200 initially healthy foals were collected from birth to ...
Gomes C, Coheur L, Tilley P.Equine asthma is a prevalent respiratory disease that negatively impacts horses' health and athletic performance. Traditional diagnostic methods are invasive and require specialised equipment. There is a need for a non-invasive, cost-effective screening tool that can be used by veterinarians and horse handlers in ambulatory settings. Objective: To assess the willingness of veterinarians and horse handlers to adopt such a tool (Questionnaire 1) and the challenges associated with visually recognising equine asthma (Questionnaire 2) and to develop EquiBreathe, an artificial intelligence (AI)-powe...
Vicenti C, Cercone M, Nieman G, Habashi NM, Andrews P, Satalin J, Velarde P, Mitchell KJ, Louie EW, Albano V, Ali H, King A, Staffieri F, Gleed R....To compare early versus late time-controlled adaptive ventilation (TCAV) for setting airway pressure release ventilation (APRV) on arterial oxygenation in dorsally recumbent anesthetized horses. Methods: A crossover, nonrandomized, experimental study. Methods: Six healthy adult horses. Methods: Each horse underwent two anesthetics: 1) volume-controlled ventilation (VCV) began for 30 minutes before switching to APRV using the TCAV method (late TCAV, TCAV); and 2) ventilation began immediately with TCAV (early TCAV, TCAV). The study lasted 180 minutes, with arterial blood gases and respiratory m...
