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Leduc L, Leclère M, Lavoie JP. Towards personalized medicine for the treatment of equine asthma. Vet J 2024; 305:106125. [PMID: 38704018 DOI: 10.1016/j.tvjl.2024.106125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/22/2024] [Accepted: 04/26/2024] [Indexed: 05/06/2024]
Abstract
Although horses with asthma share similar clinical signs, the heterogeneity of the disease in terms of severity, triggering factors, inflammatory profile, and pathological features has hindered our ability to define biologically distinct subgroups. The recognition of phenotypes and endotypes could enable the development of precision medicine, including personalized, targeted therapy, to benefit affected horses. While in its infancy in horses, this review outlines the phenotypes of equine asthma and discusses how knowledge gained from targeted therapy in human medicine can be applied to evaluate the potential opportunities for personalized medicine in equine asthma and to suggest avenues for research to advance this emerging field.
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Affiliation(s)
- Laurence Leduc
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC J2S 2M2, Canada
| | - Mathilde Leclère
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC J2S 2M2, Canada
| | - Jean-Pierre Lavoie
- Department of Clinical Sciences, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, QC J2S 2M2, Canada.
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2
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Bizzotto D, Paganini S, Stucchi L, Palmisano Avallone M, Ramirez EM, Pompilio PP, Ferrucci F, Lavoie JP, Dellaca RL. A portable fan-based device for evaluating lung function in horses by the forced oscillation technique. Physiol Meas 2022; 43. [PMID: 35120344 DOI: 10.1088/1361-6579/ac522e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 02/04/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The assessment of lung mechanics in horses is nowadays based on invasive methods that may require sedation. The forced oscillation technique (FOT) allows the non-invasive assessment of respiratory mechanics during spontaneous breathing, but current devices are complex, cumbersome, expensive, and difficult to be applied in horses. APPROACH We developed a portable FOT device based on a novel approach in which the pressure waveforms are generated by a servo-controlled ducted fan. This new approach allows the design of devices that are more sturdy, compact, and portable compared to already existing approaches. The prototype includes 1) a small microcontroller-based electronic board for controlling the fan and measuring flow and pressure and 2) an optimized data processing algorithm. MAIN RESULTS This device provides a maximum error of 0.06 cmH2O∙s/L and 0.15 cmH2O∙s/L in measuring respiratory resistance and reactance during in-vitro validation. A pilot study was also performed on three healthy horses and three horses with severe equine asthma (SEA) and it demonstrated good tolerability and feasibility of the new device. Total respiratory system resistance (Rrs) and reactance (Xrs) significantly differed (p<0.05) between groups. At 5Hz, Rrs was 0.66±0.02 cmH2O∙s/L and 0.94±0.07 cmH2O∙s/L in healthy and in SEA, respectively. Xrs 0.38±0.02 cmH2O∙s/L and -0.27±0.05 cmH2O∙s/L. SIGNIFICANCE This novel approach for applying FOT allowed the development of a small, affordable and portable device for the non-invasive evaluation of respiratory mechanics in spontaneously breathing horses, providing a useful new tool for improving veterinary respiratory medicine. Moreover, our results provide supporting evidence of the value of this novel approach for developing portable FOT devices also for applications in humans.
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Affiliation(s)
- Davide Bizzotto
- DEIB, Politecnico di Milano Dipartimento di Elettronica Informazione e Bioingegneria, Via Giuseppe Colombo, 40, Milano, 20133, ITALY
| | - Stefano Paganini
- DEIB, Politecnico di Milano Dipartimento di Elettronica Informazione e Bioingegneria, Via Giuseppe Colombo, 40, Milano, Milano, 20133, ITALY
| | - Luca Stucchi
- Equine Sports Medicine Lab (ESM-Lab), Università degli Studi di Milano Dipartimento di Medicina Veterinaria, Via dell'Università, 6, 26900 Lodi LO, Lodi, Lombardia, 26900, ITALY
| | - Matteo Palmisano Avallone
- DEIB, Politecnico di Milano Dipartimento di Elettronica Informazione e Bioingegneria, Via Giuseppe Colombo, 40, Milano, Milano, 20133, ITALY
| | - Esther Millares Ramirez
- Equine Asthma Laboratory, Université de Montréal Faculté de médecine vétérinaire, 3200 Rue Sicotte, Saint-Hyacinthe, QC J2S 2M2, Canada, Saint Hyacinthe, Quebec, J2S 7C6, CANADA
| | - Pasquale P Pompilio
- Restech srl, Via Melchiorre Gioia, 61, 20124 Milano MI, Milano, 20124, ITALY
| | - Francesco Ferrucci
- Equine Sports Medicine Lab (ESM-Lab), Università degli Studi di Milano Dipartimento di Medicina Veterinaria, Via dell'Università, 6, 26900 Lodi LO, Lodi, Lombardia, 26900, ITALY
| | - Jean-Pierre Lavoie
- Equine Asthma Laboratory, Université de Montréal Faculté de médecine vétérinaire, 3200 Rue Sicotte, Saint-Hyacinthe, QC J2S 2M2, Canada, Saint Hyacinthe, Quebec, J2S 2M2, CANADA
| | - Raffaele L Dellaca
- DEIB, Politecnico di Milano Dipartimento di Elettronica e Informazione, Via Giuseppe Colombo, 40, Milano, Milano, Lombardia, 20133, ITALY
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3
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Pirie RS, Couëtil LL, Robinson NE, Lavoie JP. Equine asthma: An appropriate, translational and comprehendible terminology? Equine Vet J 2017; 48:403-5. [PMID: 27292020 DOI: 10.1111/evj.12586] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R S Pirie
- Royal (Dick) School of Veterinary Studies and Roslin Institute, University of Edinburgh, Midlothian, UK
| | - L L Couëtil
- College of Veterinary Medicine, Veterinary Clinical Sciences, Purdue University, West Lafayette, IN, USA
| | - N E Robinson
- Large Animal Clinical Sciences, Michigan State University, East Lansing, USA
| | - J-P Lavoie
- Université de Montréal, Saint-Hyacinthe, QC, Canada
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4
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Mazan MR. Update on noninfectious inflammatory diseases of the lower airway. Vet Clin North Am Equine Pract 2015; 31:159-85. [PMID: 25770068 DOI: 10.1016/j.cveq.2014.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Inflammatory airway disease and recurrent airway obstruction are 2 nonseptic diseases of the equine respiratory system with a shared cause of exposure to particulate matter. They appear to occupy 2 ends of a spectrum of disease, but are differentiated by history, clinical signs, and response to treatment. Diagnosis can be made by sampling of respiratory fluids and lung function testing. Treatment consists of environmental modification and pharmacologic treatment with systemic or inhaled corticosteroids and bronchodilators.
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Affiliation(s)
- Melissa R Mazan
- Large Animal Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, 200 Westborough Road, North Grafton, MA 01536, USA.
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5
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Bosshard S, Gerber V. Evaluation of coughing and nasal discharge as early indicators for an increased risk to develop equine recurrent airway obstruction (RAO). J Vet Intern Med 2014; 28:618-23. [PMID: 24417562 PMCID: PMC4858023 DOI: 10.1111/jvim.12279] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 10/12/2013] [Accepted: 11/19/2013] [Indexed: 11/29/2022] Open
Abstract
Background It is often assumed that horses with mild respiratory clinical signs, such as mucous nasal discharge and occasional coughing, have an increased risk of developing recurrent airway obstruction (RAO). Hypothesis Compared to horses without any clinical signs of respiratory disease, those with occasional coughing, mucous nasal discharge, or both have an increased risk of developing signs of RAO (frequent coughing, increased breathing effort, exercise intolerance, or a combination of these) as characterized by the Horse Owner Assessed Respiratory Signs Index (HOARSI 1–4). Animals Two half‐sibling families descending from 2 RAO‐affected stallions (n = 65 and n = 47) and an independent replication population of unrelated horses (n = 88). Methods In a retrospective cohort study, standardized information on occurrence and frequency of coughing, mucous nasal discharge, poor performance, and abnormal breathing effort—and these factors combined in the HOARSI—as well as management factors were collected at intervals of 1.3–5 years. Results Compared to horses without clinical signs of respiratory disease (half‐siblings 7%; unrelated horses 3%), those with mild respiratory signs developed clinical signs of RAO more frequently: half‐siblings with mucous nasal discharge 35% (P < .001, OR: 7.0, sensitivity: 62%, specificity: 81%), with mucous nasal discharge and occasional coughing 43% (P < .001, OR: 9.9, sensitivity: 55%, specificity: 89%); unrelated horses with occasional coughing: 25% (P = .006, OR = 9.7, sensitivity: 75%, specificity: 76%). Conclusions and Clinical importance Occasional coughing and mucous nasal discharge might represent an increased risk of developing RAO.
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Affiliation(s)
- S Bosshard
- Swiss Institute of Equine Medicine, University of Berne and ALP-Haras, Berne, Switzerland
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Abstract
Asthma is an inflammatory disease characterized by airways obstruction, airways hyperresponsiveness, excessive mucous secretion and cough. Guinea pig airways display many anatomical, physiological and pharmacological attributes of human airways, making this species ideal for modeling the asthmatic condition. This unit provides an overview of animal models of asthma, including definitions, descriptions of available animal models, and discussion of numerous critical issues to consider before designing a model to study this complex disease.
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Kutasi O, Balogh N, Lajos Z, Nagy K, Szenci O. Diagnostic Approaches for the Assessment of Equine Chronic Pulmonary Disorders. J Equine Vet Sci 2011. [DOI: 10.1016/j.jevs.2011.03.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Katavolos P, Ackerley CA, Viel L, Clark ME, Wen X, Bienzle D. Clara cell secretory protein is reduced in equine recurrent airway obstruction. Vet Pathol 2009; 46:604-13. [PMID: 19276063 DOI: 10.1354/vp.08-vp-0255-b-fl] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Horses are prone to recurrent airway obstruction (RAO), an inflammatory lung disease induced by repeated exposure to environmental mold, dust, and bacterial components. Active disease manifests with mucus hyperproduction, neutrophilic inflammation, bronchoconstriction, and coughing. Chronically affected animals have lung remodeling characterized by smooth muscle hyperplasia, collagen deposition, lymphoid hyperplasia, and impaired aerobic performance. Clara cell secretory protein (CCSP) counters inflammation in the lung, hence we hypothesized that CCSP depletion is a key feature of RAO in horses. Recombinant equine CCSP and specific antiserum were produced, and percutaneous lung biopsies were obtained from 3 healthy horses and from 3 RAO-affected horses before and after induction of RAO. CCSP relative gene expression in tissue, as well as protein concentration in lung lavage fluid, was determined. Immunocytochemical analysis, using both light and immunogold ultrastructural methods, demonstrated reduced CCSP staining in lung tissue of animals with RAO. Immunogold label in Clara cell granules was less in animals with chronic RAO than in normal animals, and absent in animals that had active disease. Median lung lavage CCSP concentration was 132 and 129 ng/ml in healthy horses, and 62 and 24 ng/ml in RAO horses before and after challenge, respectively. CCSP lung gene expression was significantly higher in healthy animals than in animals with chronic RAO. Together, these preliminary findings suggest that reduced production of CCSP and subcellular changes in Clara cells are features of chronic environmentally induced lung inflammation in horses.
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Affiliation(s)
- P Katavolos
- Department of Pathobiology, University of Guelph, Guelph, ON, N1G 2W1, Canada
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Hoffman AM. Bronchoalveolar lavage: sampling technique and guidelines for cytologic preparation and interpretation. Vet Clin North Am Equine Pract 2008; 24:423-35, vii-viii. [PMID: 18652963 DOI: 10.1016/j.cveq.2008.04.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
Bronchoalveolar lavage (BAL) is a method for the recovery of respiratory secretions that line the peripheral airways and alveoli. Overall, BAL is considered very safe and sufficiently sensitive to detect inflammation at the cytologic level. The good correlation between BAL differential cell counts and exercise-induced hypoxemia or lactic acidosis, airway obstruction, or airway responsiveness attests to the relevance of BAL cytology to the structure and function of the equine airways. Thus, an important advantage of BAL over tracheal wash cytology is that BAL cytology relates well to the clinical signs and pathophysiologic consequences of inflammatory airway disease.
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Affiliation(s)
- Andrew M Hoffman
- Tufts University, Cummings School of Veterinary Medicine, 200 Westboro Road, North Grafton, MA 01539, USA.
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Bedenice D, Mazan MR, Hoffman AM. Association between cough and cytology of bronchoalveolar lavage fluid and pulmonary function in horses diagnosed with inflammatory airway disease. J Vet Intern Med 2008; 22:1022-8. [PMID: 18498325 DOI: 10.1111/j.1939-1676.2008.0109.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND The objective of this study was to examine the relationship between chronic cough, pulmonary mechanical function, bronchial hyper-responsiveness, and peripheral airway inflammation in adult performance horses with nonseptic inflammatory airway disease (IAD). HYPOTHESIS We hypothesized that horses with a presenting complaint of cough have a higher percentage of inflammatory cells on bronchoalveolar lavage (BAL), greater airway obstruction, and airway hyper-responsiveness (AHR) than do horses without cough. ANIMALS/SAMPLE POPULATION: Adult performance horses (n = 137) referred for evaluation of signs of IAD including cough or exercise intolerance (university hospital patients) and BAL samples (n = 142) taken in first opinion practice. METHODS A descriptive, retrospective cohort analysis was performed to evaluate the association between chronic cough and pulmonary mechanical function, AHR, BAL cytology, patient signalment, and comorbid features (multivariable logistic regression). RESULTS Cough was significantly more prevalent in horses >7 years, and best characterized by a high BAL neutrophil count (>5%) and nasal discharge. Lung function mechanics, abnormal thoracic auscultation, and exercise intolerance did not retain statistical significance in the logistical regression analysis of cough. Although AHR was not related to neutrophilic airway inflammation (BAL neutrophils >5%), it was significantly associated with BAL mast cells >2%. CONCLUSIONS AND CLINICAL IMPORTANCE Our data support that neutrophilic airway inflammation may potentiate cough without further changing respiratory mechanical function in IAD. In contrast, mast cell release increased AHR without affecting the incidence of cough. Cough may be used as an indicator of neutrophilic airway inflammation in the presence of low-grade nonseptic respiratory disease.
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Affiliation(s)
- D Bedenice
- Department of Clinical Sciences, Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA
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11
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Pirrone F, Albertini M, Clement MG, Lafortuna CL. Respiratory mechanics in Standardbred horses with sub-clinical inflammatory airway disease and poor athletic performance. Vet J 2007; 173:144-50. [PMID: 16129634 DOI: 10.1016/j.tvjl.2005.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The aim of this study was to investigate and quantify respiratory mechanical dysfunctions in Standardbred horses with both poor performance and bronchoalveolar lavage fluid cytology characteristic of inflammatory airway disease (IAD). A control group of healthy Standardbred horses was compared. Respiratory mechanics and breathing pattern were examined at rest and during hyperventilation induced using a rebreathing method. At rest, respiratory mechanics and breathing pattern were superimposable in both groups. In IAD horses, rebreathing increased ventilation, with larger tidal volumes and lower respiratory frequencies. During hyperventilation, IAD animals showed frequency-dependent dynamic lung compliance, and had greater viscous lung resistance and rate of dynamic work of breathing. As IAD alters pulmonary mechanics, the ventilatory load increases and horses requiring significantly higher energy for breathing may suffer restrictions in their athletic performance. This rebreathing method permits early evaluation of respiratory mechanical dysfunction in poorly performing horses with sub-clinical IAD.
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Affiliation(s)
- Federica Pirrone
- Dipartimento di Patologia Animale, Igiene e Sanità Pubblica Veterinaria, Sezione di Biochimica e Fisiologia, Università degli Studi di Milano, via Celoria 10-20133 Milano, Italy
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12
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Horohov DW, Beadle RE, Mouch S, Pourciau SS. Temporal regulation of cytokine mRNA expression in equine recurrent airway obstruction. Vet Immunol Immunopathol 2005; 108:237-45. [PMID: 16098607 DOI: 10.1016/j.vetimm.2005.07.013] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Acute and chronic inflammation of the airway remains an important health problem for equids. "Heaves" or recurrent airway obstruction (RAO) remains one of the most commonly diagnosed conditions affecting the lung of older horses in Europe and the United States. The typical clinical signs of RAO include non-productive coughing, serous nasal discharge, labored expiratory effort, and flaring of the nostrils. Auscultation of the lungs of the affected horse often reveals abnormal respiratory sounds, described as crackles and wheezes, throughout the area of the lung field. These clinical signs occur secondary to an inflammatory response that results in bronchospasm, excessive mucus production and airway obstruction. This inflammatory response is characterized by the presence of excessive mucus and inflammatory cells, primarily neutrophils, in the small airways. Most evidence suggests that RAO is the result of a pulmonary hypersensitivity to inhaled antigens. Exposure of affected horses to hay dust, pollens, and mold spores leads to neutrophil accumulation in the lung and bronchospasm. The identification of allergen-specific IgE in bronchoalveolar lavage (BAL) fluid and sera of affected horses supports the involvement of a late phase, IgE-mediated, hypersensitivity reaction in the pathogenesis of equine RAO. The production of IgE antibodies is regulated by the cytokines IL-4 and IL-13. Using a quantitative PCR method we have reported that horses with RAO exhibit a modified Type 2 cytokine response characterized by the production of IL-4 and IL-13 mRNA, but not IL-5 mRNA in BAL cells. Interferon-gamma mRNA was also elevated, suggesting a mixed response. While these results are consistent with equine RAO being the result of an aberrant Type 2 cytokine response to inhaled allergens, others have failed to find any evidence of elevated Type 2 cytokine mRNA in BAL from horses with "heaves". It is likely that these disparate results could be the result of differences in the clinical stage of the affected animals or the timing of sample collection. Here, we report a diverse pattern of cytokine gene expression when sampling a group of affected horses over a period of time.
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Affiliation(s)
- D W Horohov
- Department of Veterinary Science, Maxwell Gluck Equine Research Center, University of Kentucky, Lexington, KY 40546-0099, USA.
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Abstract
Respiratory diagnostic instruments previously available only to referral centers should be converted into miniature, portable, wireless medical devices for use in practice. Internet and wireless connections of these instruments should expedite the process of seeking second opinions and in general information sharing. We are moving into a world of greater objectivity that should free us from speculation in some areas, yet open new avenues for research and innovation in others.
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Affiliation(s)
- A M Hoffman
- Lung Function Testing Laboratory, Tufts University School of Veterinary Medicine, North Grafton, Massachusetts 01536, USA.
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Sánchez A, Couëtil L, Ward M, Clark S. Effect of Airway Disease on Blood Gas Exchange in Racehorses. J Vet Intern Med 2005. [DOI: 10.1111/j.1939-1676.2005.tb02663.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Mazan MR, Hoffman AM. Clinical techniques for diagnosis of inflammatory airway disease in the horse. ACTA ACUST UNITED AC 2003. [DOI: 10.1053/s1534-7516(03)00067-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Davis E, Rush BR. Equine recurrent airway obstruction: pathogenesis, diagnosis, and patient management. Vet Clin North Am Equine Pract 2002; 18:453-67, vi. [PMID: 12516928 DOI: 10.1016/s0749-0739(02)00026-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recurrent airway obstruction is a condition that affects some older horses maintained in confinement. Clinical signs range from exercise intolerance with occasional cough to dyspnea at rest. Bronchoalveolar lavage cytology is characterized by neutrophilic leukocytosis (15%-85%) and is recommended for making the diagnosis in horses with mild to moderate disease. Environmental management combined with periodic bronchodilator and antiinflammatory corticosteroid therapy yields the best prognosis for disease remission.
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Affiliation(s)
- Elizabeth Davis
- Department of Veterinary Clinical Sciences, Mosier Hall, Kansas State University, Manhattan, KS 66506, USA.
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Bowles KS, Beadle RE, Mouch S, Pourciau SS, Littlefield-Chabaud MA, Le Blanc C, Mistric L, Fermaglich D, Horohov DW. A novel model for equine recurrent airway obstruction. Vet Immunol Immunopathol 2002; 87:385-9. [PMID: 12072262 DOI: 10.1016/s0165-2427(02)00081-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Equine recurrent airway obstruction (RAO; a term combining both chronic obstructive pulmonary disease (COPD) and summer pasture associated obstructive pulmonary disease (SPAOPD)) is one of the most common equine respiratory diseases with up to 50% of horses affected worldwide. The etiopathogenesis of RAO is unknown although pulmonary hypersensitivity to inhaled mold antigens may be involved. Recent work in our laboratory demonstrating elevated levels of IL-4 and IL-13 mRNA in the airways and peripheral blood of horses with RAO is consistent with an atopic component to RAO. Little is known regarding the earliest phases of RAO in horses. Here we describe the development of a novel airway model for equine RAO that utilizes ovalbumin-coated polystyrene beads for airway sensitization and challenge. Aerosol challenge of sensitized ponies with OVA-coated microbeads resulted in decreased airway compliance, increased percentage of lymphocytes and neutrophils in the bronchoalveolar lavage fluid, and evidence of a Th2 cytokine response in the bronchoalveolar cells. These results suggest that this approach may be useful in describing the initial stages of RAO development in the horse.
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Affiliation(s)
- K S Bowles
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
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