Lung health in horses encompasses the study of respiratory system function, disease, and maintenance in equine species. The equine respiratory system is vital for oxygen exchange and plays a significant role in overall health and athletic performance. Conditions affecting lung health include inflammatory airway disease (IAD), recurrent airway obstruction (RAO), and exercise-induced pulmonary hemorrhage (EIPH). These conditions can impact a horse's respiratory efficiency and performance capabilities. Research in this area often focuses on understanding the pathophysiology, diagnosis, and management of respiratory diseases, as well as the impact of environmental factors on lung function. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, diagnostic approaches, and therapeutic strategies related to lung health in horses.
Yoshikawa H, Yasu T, Ueki H, Oyamada T, Oishi H, Anzai T, Oikawa M, Yoshikawa T.To evaluate the possibility that Streptococcus equi subsp. zooepidemicus (S.z) the causative bacterial agent of equine shipping fever pneumonia (ESFP), as well as to investigate its pathogenesis, 10 horses (seven Thoroughbreds and three Anglo-Arab species, ranging from 2-4 years in age) were experimentally inoculated, via an endoscope, into bronchus of the lung lobe with a dose of 30 ml of 1-7 x 10(8) CFU/ml of S.z. After inoculation, autopsy and pathological examinations were sequentially conducted 30 min, 1, 2, 3, 4, 17, 20 hr and 2 weeks later. Pneumonia induced by the intrapulmonary inocul...
Lafortuna CL, Saibene F, Albertini M, Clement MG.Horses display remarkable aerobic capabilities, attaining during muscular exercise a maximal rate of oxygen consumption about 30-fold higher than the resting value, and 2.5-fold higher than that of other mammals of similar body mass. Under these circumstances an enormous mechanical burden is expected to impinge on the equine respiratory pump and regulatory mechanisms aiming to minimize this load may play an important role in determining the adequacy of the respiratory system to the metabolic requirements. The behaviour of the respiratory system has been investigated in horses at rest and durin...
Picandet V, Léguillette R, Lavoie JP.Corticosteroids are currently the most effective drugs for the control of 'heaves' in horses. However, there is limited information concerning the comparative efficacy and tolerability of the various corticosteroids when used for treatment. Objective: To compare the therapeutic and side effects of isoflupredone acetate to those of dexamethasone. Methods: A parallel design to compare the effects of 2 corticosteroids by evaluating lung function, serum cortisol and electrolyte concentrations, response to ACTH stimulation and haematology sequentially during a 14 day control period (no treatment), ...
Kolm G, Zappe H, Schmid R, Riedelberger K, Van den Hoven R.Five horses with moderate to severe chronic obstructive pulmonary disease (COPD) were treated with 0.11 (0.01) mg/kg bodyweight of montelukast, a cysteinyl leukotriene receptor antagonist, once a day for 26 days. The horses were evaluated clinically and endoscopically and subjected to arterial blood gas analysis and lung function tests before and after the period of treatment, and the plasma concentrations of montelukast were determined by high-performance liquid chromatography with fluorescence detection. The treatment did not result in statistically significant differences in the total score...
MacNeill AL, Alleman AR, Franklin RP, Long M, Giguère S, Uhl E, López-Martinez A, Wilkerson M.A 5-year-old Paso-Fino mare was presented for severe respiratory distress. The mare had foaled 2 months prior to presentation. The horse was in poor body condition with a dull hair coat. A mild fever was noted during physical examination and increased bronchovesicular sounds were auscultated. Thoracic radiographs showed an interstitial pattern and an alveolar infiltrate with distinct air bronchograms. Moderate purulent inflammation with increased mucus was observed in tracheal wash fluid, but no infectious agents were identified. A bronchoalveolar lavage (BAL) contained a large amount of mucus...
van den Hoven R, Zappe H, Zitterl-Eglseer K, Jugl M, Franz C.The effects of an oral preparation containing an extract of thyme and primula (Bronchipret; Bionorica) on the lung function of five horses suffering heaves were determined in a longitudinal study. The horses accepted the product well. The plasma concentrations of the marker substance, thymol, indicated that at least one of the substances in the extract had been absorbed from the gastrointestinal tract. The compliance, pulmonary pressure and airway resistance of the horses' lungs were all significantly improved after one month of treatment However, the severity of their clinical signs and their...
Léguillette R.Heaves, or recurrent airway obstruction (RAO), is a chronic respiratory disease featuring lower airway inflammation, bronchoconstriction, and mucus accumulation. Inhaled organic dusts and T helper 2 type immunologic reactions are involved in the complex pathophysiology of RAO. Clinical signs vary and alternate with remission periods. The diagnosis is often based on history and clinical examination in severe cases, but bronchoalveolar lavage may be useful for the detection of early cases. The most important aspect of treatment is to avoid exposure to allergens. Corticosteroids may be administer...
Rickards KJ, Page CP, Lees P, Gettinby G, Cunningham FM.Phosphodiesterase 4 (PDE4) inhibitors have been shown to inhibit equine neutrophil function in vitro and may be of benefit in recurrent airway obstruction (RAO), an allergy-based respiratory disease characterized by inflammatory cell recruitment and activation within the lungs following exposure of susceptible horses to allergens in mouldy hay. The aim of this study was to evaluate the inhibitory effects of the PDE4 inhibitor, rolipram, in an in vitro assay of thromboxane (Tx) production. The assay was then used to monitor the activity of this compound in vivo in normal and RAO-affected horses...
Herholz CP, Gerber V, Tschudi P, Straub R, Imhof A, Busato A.To investigate whether volumetric capnography indices could be used to differentiate between horses without recurrent airway obstruction (RAO) and horses with RAO that were in clinical remission or that had clinically apparent RAO. Methods: 70 adult Swiss Warmblood horses (20 used for pleasure riding and 50 used for dressage or show jumping). Methods: Horses were allocated to 4 groups on the basis of history, clinical signs, results of endoscopy, and cytologic findings (group 1, 21 healthy horses; group 2, 22 horses with RAO that were in remission; group 3, 16 horses with mild RAO; group 4, 11...
Hines SA, Stone DM, Hines MT, Alperin DC, Knowles DP, Norton LK, Hamilton MJ, Davis WC, McGuire TC.Rhodococcus equi is a gram-positive bacterium that infects alveolar macrophages and causes rhodococcal pneumonia in horses and humans. The virulence plasmid of R. equi appears to be required for both pathogenicity in the horse and the induction of protective immunity. An understanding of the mechanisms by which virulent R. equi circumvents protective host responses and by which bacteria are ultimately cleared is important for development of an effective vaccine. Six adult horses were challenged with either virulent R. equi or an avirulent, plasmid-cured derivative. By using a flow cytometric m...
Pratt SM, Stacy BA, Whitcomb MB, Vidal JD, De Cock HE, Wilson WD.A 13-year-old Morgan gelding was evaluated because of a mass in the caudal region of the abdomen. The horse had been presumed to be a gelding, but necropsy findings revealed a retained testis in the right retroperitoneal space. Histologically, the retained testis contained neoplastic cells; metastases were identified in the liver, spleen, lungs, and sublumbar lymph nodes. Immunohistochemical examination of the testis and metastatic tissues confirmed the diagnosis of malignant Sertoli cell tumor. Testicular neoplasms are infrequently reported in stallions. Seminomas are most commonly reported, ...
Pusterla N, Pesavento PA, Leutenegger CM, Hay J, Lowenstine LJ, Durando MM, Magdesian KG.Adiaspiromycosis is a fungal disease of the lung caused by the saprophytic soil mould Emmonsia crescens or, more rarely, E. p a rv a. The fungus affects lower order mammals, mostly rodents, and rarely man, although the organism is distributed worldwide (Sigler 1998). In veterinary medicine, the disease has been reported as an incidental histopathological finding in the lungs of one goat and 2 dogs (Al-Doory et al. 1971; Koller et al. 1976; Koller and Helfer 1978). The term adiaspiromycosis derives from the conidia of this fungus, the adiaconidia, which exhibit the unique property of progressiv...
Kirschvink N, Fiévez L, Bougnet V, Art T, Degand G, Smith N, Marlin D, Roberts C, Harris P, Lekeux P.An oxidant/antioxidant imbalance in favour of oxidants has been identified as playing a decisive role in the pathogenesis of chronic inflammatory airway diseases. Nutritional antioxidant supplementation might reduce oxidative damage by enhancement of the antioxidant defence, thereby modulating inflammatory processes. In a placebo-controlled, blind study, it was tested whether a dietary antioxidant supplement administered for 4 weeks would improve lung function and reduce airway inflammation in heaves-affected horses. Eight horses in clinical remission of heaves were investigated at rest and af...
Harmegnies NF, Duvivier DH, Vandenput SN, Art T, Lekeux PM, Votion DM.This study aimed to compare exercise-induced pulmonary perfusion redistribution in healthy vs. 'heavey' horses using scintigraphy, a minimally invasive technique. Six healthy (A) and 5 'heavey' horses in remission (B(I)) and during clinical signs of disease (B(II)) were investigated. Dimensions of the exercising pulmonary perfusion (QE) images were expressed in percent of the resting perfusion (QR) images. Computed QE to QR ratios (QE/QR) images enabled the definition of the region more perfused at exercise than at rest (R1). In all groups, exercise induced a major enlargement of the Q image b...
McKane SA, Slocombe RF.Necropsy studies of horses suffering exercise-induced pulmonary haemorrhage (EIPH) have identified mild inflammatory lesions with evidence of alveolar fibrosis and bronchiolitis. These lesions were thought to be the result of viral infections that predisposed the affected regions of the lung to EIPH. We have shown previously that during erythrophagocytosis in the alveolar space, there is a prolonged period of macrophage influx and activation. This present study used morphometric analysis to quantify the effects of macrophage activity during erythrophagocytosis, on the alveolar cell population ...
Art T, Tack S, Kirschvinck N, Busoni V, Votion D, Freeman K, Lekeux P.This study aimed at measuring the functional consequences and the pulmonary cytology changes following a simulation of pulmonary haemorrhage. Pulmonary function tests including lobeline-induced hyperventilation, cytology of tracheo-bronchial wash (TBW) and thoracic radiographs were performed before, as well as 1, 7, 14 and 28 days after, the instillation of 300 ml of blood into the lungs of 4 horses deemed free of exercise-induced pulmonary haemorrhage (Group 1). Control data (Group 2) were obtained by instilling the same volume of saline into the lungs of the same horses in a crossover design...
Lugo J, Stick JA, Peroni J, Harkema JR, Derksen FJ, Robinson NE.To evaluate the safety and efficacy of thoracoscopically guided pulmonary wedge resection in horses. Methods: 10 horses (5 control horses and 5 horses affected with recurrent airway obstruction [ie, heaves]). Methods: Each horse underwent a thoracoscopically guided pulmonary wedge resection. Before, during, and after surgery, heart rate, respiratory rate, arterial blood gases, and systemic and pulmonary arterial pressures were measured. Physical examination, CBC, and thoracic radiography and ultrasonography were performed 24 hours before and 2 and 48 hours after surgery. Pulmonary specimens we...
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...
Sander K, Deegen E, Ohnesorge B.In a placebo-controlled drug study data were collected about flow, volume and expiratory CO2-concentration in 13 horses with chronic obstructive pulmonary disease before and until 2.5 h after intravenous injection of clenbuterol. An ultrasonic flow measuring unit and an infrared-CO2-analyser (Spiroson Scientific) were used. functional deadspace and expiratory mixed volume were calculated. In addition the effect on the partial pressure of oxygen (PaO2) and carbon dioxide (PaCO2) in arterial blood was tested and the alveolo-arterial oxygen difference (AaDO2) determined. The volume of the functio...
MacGillivray KC, Sweeney RW, Del Piero F.The clinical and pathologic findings are reviewed for 14 horses with metastatic melanoma. All were older gray horses, with an average age of 16 years. The most common sites of primary tumors were the ventral tail, perineum, and parotid salivary gland. Metastases were found in multiple locations and caused a variety of clinical syndromes. The most common sites for metastases were the lymph nodes, liver, spleen, skeletal muscle, lungs, and surrounding or within blood vessels throughout the body. Many of the horses had dermal melanomas for years (range 1-6 years) before succumbing to metastatic d...
Pirie RS, McLachlan G, McGorum BC.Currently, heaves is investigated by exposing susceptible horses to dusty hay. Consequently, the response will be dependent on the organic dust content and composition of the hay. It was hypothesised that the use of a hay dust suspension (HDS) would reduce the variability of the challenge and therefore standardise experimental protocols. Furthermore, analysis of HDS would also permit further investigation of the organic dust components responsible for the response. Three hay dust suspensions (HDS-1, 2 and 3) were prepared for use in the diagnosis and investigation of heaves. HDS were produced ...
Pickles K, Pirie RS, Rhind S, Dixon PM, McGorum BC.The aim of this study was to investigate whether initial equine bronchoalveolar lavage fluid (BALF) aliquots were more representative of bronchial cytology that bronchiolar and alveolar cytology. Cell viability and total nucleated (TCC), differential (DCC) and absolute cell counts of cytocentrifuged preparations of 3 sequentially collected BALF aliquots (Aliquots 1-3) were compared with those of pooled BALF (Aliquot 4) to assess whether all aliquots were representative of the lavaged lung segment. BALF samples (n = 21) were collected from control horses (n = 5) or heaves-affected horses (n = 5...
Ohnesorge B, Gehlen H, Wohlsein P.Description of transendoscopic electrosurgical treatment of a pulmonary granular cell tumor in a horse. Methods: Case report. Methods: A 12-year-old Standardbred mare. Methods: After endoscopic examination and transendoscopic biopsy, a granular cell tumor nodule was removed transendoscopically from the right principal bronchus of the sedated horse (0.02 mg/kg detomide intravenous) with a monopolar electrosurgical wire snare. Two days later, the surgical area was irradiated transendoscopically using a Nd-YAG laser. Results: After surgery, the horse had no further signs of respiratory disease. C...
Herholz C, Straub R, Gerber V, Wampfler B, Lüthi S, Imhof A, Moens Y, Busato A.The pulmonary health of 66 horses was assessed by a clinical examination and simple supplementary diagnostic methods. Single breath diagrams for CO(2) (SBD-CO(2)) and derived lung function indices were used to determine pulmonary function. The clinical signs in different groups were related to the results of the lung function indices derived from the SBD-CO(2). In horses with moderate to severe chronic obstructive pulmonary disease (COPD), a significant relationship was found between the respiratory frequency and the ratio of Bohr's dead space to the tidal volume (VD(Bohr)/VT), and between the...
Kirschvink N, Di Silvestro F, Sbaï I, Vandenput S, Art T, Roberts C, Lekeux P.This study aimed to test whether shredded cardboard is an appropriate minimum-dust bedding material for heaves-affected horses. Results of standardized in vitro measurement of airborne dust and aeroallergen concentrations of cardboard bedding were significantly lower than those of common bedding materials. Six heaves-affected horses in clinical remission after pasturing were stabled for two months on cardboard bedding and fed grass silage. Pulmonary function tests (PFT: ventilatory mechanics, arterial blood gases, airway inflammation scoring, bronchoalveolar cytology) were performed before, du...
Lindberg A, Näsman-Glaser B, Lindgren JA, Robinson NE.To evaluate leukotriene (LT) biosynthetic capacity in lung tissue from healthy horses and horses with recurrent airway obstruction (RAO). Methods: Lung parenchyma and airway specimens from 8 RAO-affected and 5 healthy horses. Methods: Horses were stabled for > or = 72 hours. Blood was drawn before euthanasia, after which lung specimens were collected. Tissue strips from small airways and parenchyma were incubated in organ baths with the precursor LTA4 or stimulated with calcium ionophore A23187 or the tripeptide N-formyl-Met-Leu-Phe (fMLP), with or without exogenous arachidonic acid, in the...
Heinonen E, Nyman G, Meriläinen P, Högman M.Dependent atelectatic lung areas open towards the end of inspiration when the lung opening pressure increases, and recollapse during expiration. We hypothesized that inhaled nitric oxide (NO) counteracts hypoxic vasoconstriction in these collapsing lung areas, resulting in increased pulmonary shunt perfusion. Methods: We administered NO as a pulse and varied the pulse timing during inspiration in equine anaesthesia, where atelectasis develops regularly. Six spontaneously breathing standard breed trotters were studied under isoflurane anaesthesia in lateral recumbency. NO pulsed into the first ...
Giguère S, Viel L, Lee E, MacKay RJ, Hernandez J, Franchini M.Work in humans and laboratory animals has identified a central role for cytokines and chemokines in development and persistence of lower airway inflammation. The objectives of this study were to determine interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha induction in bronchoalveolar lavage (BAL) of control horses and horses with heaves both during remission and exacerbation of the disease, and to determine the effect of therapy with inhaled fluticasone propionate on the cytokine profile of horses with heaves. IL-1 beta an...
Lavoie JP, Léguillette R, Pasloske K, Charette L, Sawyer N, Guay D, Murphy T, Hickey GJ.To evaluate whether the leukotriene (LT) D4 receptor antagonist L-708,738 is therapeutically beneficial in treating horses with recurrent airway obstruction (heaves). Methods: 12 adult horses with heaves and healthy lung lobes from 20 slaughtered horses. Methods: Lung lobes were used for smooth muscle tension and radioligand binding studies. Horses with heaves were given a placebo for 14 days and administered L-708,738 (n = 6; 2.5 mg/kg PO, q 12 h) or dexamethasone (6; 0.04 mg/kg, IV, q 24 h) from days 14 to 28. Pulmonary function was measured weekly for 36 days, and bronchoalveolar cells were...
Fugazzola M, Barton AK, Niedorf F, Kietzmann M, Ohnesorge B.Glucocorticoids have been proven to be effective in the therapy of recurrent airway obstruction (RAO) in horses via systemic as well as local (inhalative) administration. Elective analysis of the effects of this drug on bronchoconstriction in viable lung tissue offers an insight into the mechanism of action of the inflammatory cascade occurring during RAO which is still unclear. The mechanism of action of steroids in treatment of RAO is thought to be induced through classical genomic pathways. We aimed at electively studying the effects of the glucocorticoid beclomethasone dipropionate on equi...
McKane SA, Slocombe RF.Necropsy studies of horses suffering exercise-induced pulmonary haemorrhage (EIPH) have identified mild inflammatory lesions with evidence of alveolar fibrosis and bronchiolitis. These lesions were thought to be the result of viral infections that predisposed the affected regions of the lung to EIPH. We have shown previously that during erythrophagocytosis in the alveolar space, there is a prolonged period of macrophage influx and activation. This present study used morphometric analysis to quantify the effects of macrophage activity during erythrophagocytosis, on the alveolar cell population ...
Begg LM, Hughes KJ, Kessell A, Krockenberger MB, Wigney DI, Malik R.A 20-year-old Welsh Mountain Pony (212 kg) mare was initially presented for a chronic cough, fever, weight loss and low grade abdominal pain. She later developed dyspnoea, tachypnoea and exercise intolerance. The presence of multiple masses (up to 17 cm diameter) in the pulmonary parenchyma was established using lateral thoracic radiography and transthoracic ultrasonography. Encapsulated, budding yeasts were observed in smears made from transtracheal washings and needle aspirates of the pulmonary lesions. Cryptococcus gattii (synonym: Cryptococcus neoformans variety gattii; Cryptococcus bacill...
Wilkins PA, Gleed RD, Krivitski NM, Dobson A.Seven Standardbred horses were exercised on a treadmill at speeds (approximately 12 m/s) producing maximal heart rate, hypoxemia, and a mean pulmonary arterial pressure of approximately 75 mmHg. Extravascular lung water was measured by using transients in temperature and electrical impedance of the blood caused by a bolus injection of cold saline solution. Lung water was approximately 3 ml/kg body wt when standing but did not increase significantly with exertion. We conclude that any increase in fluid extravasation from the pulmonary hypertension accumulates in the lung at a level that is less...
Sweeney CR, Sweeney RW, Benson CE.Results of bacteriologic culture of specimens obtained from 14 horses with pneumonia and from 15 horses that were clinically healthy (nonpneumonia group) were compared. Specimens were obtained by use of an endoscopic guarded tracheal swabbing method and percutaneous tracheal aspiration. The percentage of agreement between the 2 tracheal specimens for the horses of the pneumonia group was 79% for aerobic isolates and 100% for anaerobic isolates. The percentage of agreement between results of the 2 tracheal specimens for horses of the nonpneumonia group was 80% for aerobic organisms and 93% for ...
Armstrong PJ, Derksen FJ, Slocombe RF, Robinson NE.We measured lung function and airway reactivity in response to methacholine and citric acid administered by aerosol in 2 groups of ponies (principal and control). Principal ponies had a history of heaves, a disease characterized by recurrent airway obstruction. Control ponies had no history of respiratory disease. Both principal and control ponies were paired (principal and control), and measurements were made when principal ponies were in clinical remission (Period A), following barn exposure when principal ponies had acute airway obstruction (Period B), and 1 and 2 wk after they were returne...
Abraham G, Kottke C, Ammer H, Dhein S, Ungemach FR.Muscarinic receptors are considered to be of comparable clinical importance in chronic obstructive pulmonary disease (COPD) in equines and in humans. At present, data are scarce on the expression and distribution of probable subtypes of these receptors and their signalling pathways in airway segments, including lung parenchyma and bronchial and tracheal epithelium with the underlying smooth muscle in horses. Specific [N-methyl-3H]scopolamine chloride ([3H]NMS) binding to all three tissues was saturable and of high affinity, with KD values ranging between 1.6+/-0.7 and 1.9+/-0.3 nmol/L. [3H]NMS...
Morini M, Gobbo F, Rinnovati R, Romagnoli N, Peli A, Massarenti C, Spadari A, Pietra M.Equine asthma is a common respiratory disease that may affect horses of any age. The diagnosis of severe equine asthma (SEA) (historically referred as recurrent airway obstruction or RAO) is based mainly on the history of the animal and clinical signs, which are further supported by the cytological examination of the bronchoalveolar lavage (BAL). This can also be helpful in monitoring the inflammation of the lower airways in response to environmental management and medication. The cytocentrifugated preparation is usually considered the method of choice for BAL cytological interpretation. The a...
Williams KJ, Derksen FJ, Defeijter-Rupp HL, Robinson NE.Exercise-induced pulmonary haemorrhage (EIPH) occurs in nearly all strenuously exercising horses. Recent studies have attempted to identify the role of free blood within the airspaces, in the lung fibrosis that develops within the lungs of EIPH horses. Objective: Repeated exposure of the equine lung to autologous blood results in lung fibrosis similar to that observed in spontaneous EIPH. Methods: Forty ml of autologous blood from the jugular vein was instilled into preselected lung regions of 6 horses one, 2, 3, 4 or 5 times at 2 week intervals, with 40 ml of saline instilled into the contral...
Szeredi L, Molnár T, Glávits R, Takai S, Makrai L, Dénes B, Del Piero F.Rhodococcus equi was isolated from lung, liver, spleen, and stomach content of two aborted equine fetuses of 7 and 8 months gestation from two different farms. Lesions included diffuse pyogranulomatous pneumonia with numerous Gram-positive coccobacilli within the cytoplasm of macrophages, multinucleated Langhans giant cells and neutrophils, and enhanced extramedullary hematopoiesis with megakaryocytosis within the liver and spleen. Detection of R. equi was made by bacteriology and immunohistochemistry for R. equi and VapA, the virulence factor of R. equi. R. equi and VapA were identified withi...
Winder NC, von Fellenberg R.The peroxidase anti-peroxidase technique was used to demonstrate free and intracellular immunoglobulin (Ig) within the lungs of 23 horses with chronic small airway disease. Histologically, all the horses had chronic bronchiolitis; however, the lesions varied in degree from mild in eight horses, to moderate in nine horses and severe in six horses. Lungs from three horses which had no gross or histopathological lesions were used as controls. In comparison with control horses, horses with mild chronic bronchiolitis had increased numbers of Ig A-containing and non-immunoglobulin staining cells aro...
Kankavi O, Ata A, Akif Ciftcioglu M.The presence of surface-active material in the lung alveolus has been known for several decades as being essential for normal lung function. The host defense and controlling inflammatory processes of the lung are the major functions of SP-A and SP-D. SP-A and SP-D were originally demonstrated in alveolar type II cells, but recent studies have shown extrapulmonary expression of SP-A and SP-D indicating systemic roles of these proteins. Present study describes the presence of SP-A and SP-D in the stallion genital tract, prepuce, prostate, testis, and seminal vesicle using Western blotting and im...
Marr KA, Foster AP, Lees P, Cunningham FM, Page CP.The effect of antigen challenge on the state of activation of peripheral blood neutrophils from horses with chronic obstructive pulmonary disease (COPD) has been determined by measuring neutrophil superoxide anion formation. Prior to a seven-hour antigen challenge superoxide anion production by neutrophils from asymptomatic horses with COPD and normal horses in response to platelet activating factor (PAF) (with and without cytochalasin B), serum treated zymosan (STZ) and phorbol myristate acetate (PMA) was similar. Agonist-induced superoxide production by neutrophils from symptomatic COPD and ...
Berlin S, Kirschbaum A, Spieckermann L, Oswald S, Keiser M, Grube M, Venner M, Siegmund W.The treatment of equine lung infections by Rhodococcus equi with rifampicin is empirically based because pharmacokinetic/pharmacodynamic (PK/PD) indices and pivotal clinical outcome data are not available. Objective: To evaluate the pharmacokinetics and pulmonary distribution of rifampicin into epithelial lining fluid (ELF) and bronchoalveolar lavage cells (BALC) to predict antimicrobial activity in the lung using PK/PD indices. Methods: Controlled, randomised, two-period, crossover, repeated-dose study with an initial arm to measure disposition after i.v. administration of rifampicin. Methods...
Bolfa P, Nolf M, Cadoré JL, Catoi C, Archer F, Dolmazon C, Mornex JF, Leroux C.EIA (Equine Infectious Anemia) is a blood-borne disease primarily transmitted by haematophagous insects or needle punctures. Other routes of transmission have been poorly explored. We evaluated the potential of EIAV (Equine Infectious Anemia Virus) to induce pulmonary lesions in naturally infected equids. Lungs from 77 EIAV seropositive horses have been collected in Romania and France. Three types of lesions have been scored on paraffin-embedded lungs: lymphocyte infiltration, bronchiolar inflammation, and thickness of the alveolar septa. Expression of the p26 EIAV capsid (CA) protein has been...
Schroter RC, Leeming A, Denny E, Bharath A, Marlin DJ.Recently we proposed that exercise-induced pulmonary haemorrhage (EIPH) results from locomotory-impact-induced trauma by impact of the scapula on the chest wall during footfall and the consequent transmission of waves through the lung. A computational model has been developed to demonstrate that wave amplification and focusing occur in the dorsocaudal tip of the lung for waves originating on the anterior subscapular surface. The propagation of an acoustic wave was investigated in a simplified 2-dimensional representation of a vertical anterio-dorsal section of horse lung. It was demonstrated t...
Koterba AM, Wozniak JA, Kosch PC.The purpose of the study was to document the developmental changes in the ventilatory and timing parameters associated with quiet breathing at rest in awake, standing horses during the first year post partum. Tidal volume (VT), breathing frequency, airflow, mechanical timing intervals and minute ventilation (VE) were measured serially in foals age 24 h-1 year. In the growing foal, VE increased due to a progressive rise in VT, in spite of a pronounced decrease in respiratory frequency. When normalised to body weight (bwt), VE/kg declined with maturation in a curvilinear fashion, from mean +/- s...
Behan AL, Hauptman JG, Robinson NE.To use noninvasive respiratory inductance plethysmography (RIP) to investigate differences in breathing patterns between horses with and without recurrent airway obstruction (RAO) during the onset of airway obstruction induced through confinement to stables. Methods: 12 horses with no history or clinical signs of respiratory disease (control horses) and 7 RAO-affected horses. Methods: The study involved 2 phases. In phase 1, the optimal position of RIP bands for recording pulmonary function was investigated in 12 control horses. In phase 2, 7 RAO-affected and 7 control horses were confined to ...
Gallivan GJ, Viel L, McDonell WN.Multiple-breath nitrogen washouts (MBNW) were performed with 29 light horses. Seven normal horses were used to examine the reproducibility, and 22, ranging from normal to severely diseased, were used to examine the changes in chronic obstructive pulmonary disease (COPD) and the effect of a bronchodilator, salbutamol, on the distribution of ventilation. The MBNW were analyzed using the functional residual capacity (FRC), end-tidal N2 concentration of the final breath of the MBNW (FETN2,fb), end-tidal N2 concentration when the cumulative expired volume was equal to body weight (FETN2,bw), lung c...
Christmann U, Welles EG, Waldridge BM, Schumacher J, Grier BL, Hite RD.Abnormalities in lung surfactant are well described in human respiratory diseases including asthma, but are poorly described in horses. Objective: Lung surfactant is abnormal in horses with clinical signs of recurrent airway obstruction (RAO). Methods: Six healthy horses and 5 horses with RAO. Methods: Bronchoalveolar lavage fluid (BALF) was obtained from all horses by standard procedures. Cell-free BALF was separated into crude surfactant pellets (CSP) and supernatant via ultracentrifugation. Phospholipid and protein content was analyzed from both of these fractions. Phospholipid composition ...
Sellon DC, Knowles DP, Greiner EC, Long MT, Hines MT, Hochstatter T, Tibary A, Dame JB.Equine protozoal myeloencephalitis is a progressive neurologic disease of horses most commonly caused by infection with the apicomplexan parasite Sarcocystis neurona. Factors affecting neuroinvasion and neurovirulence have not been determined. We investigated the pathogenesis of infection with S. neurona in horses with severe combined immune deficiency (SCID). Two immunocompetent (IC) Arabian horses and two Arabian horses with SCID were infected orally with 5 x 10(5) sporocysts of S. neurona. Four IC horses and one SCID horse were infected intravenously (i.v.) with 5 x 10(8) merozoites of the ...
Fernandes DJ, Xu KF, Stewart AG.1. Airway wall remodelling (AWR), the structural change induced by acute and chronic inflammation in the airways, may be one of the most significant and difficult to reverse components of progressive asthma. 2. The mechanisms underlying the development of AWR are not known. Studies of only the most superficial wall structures of large airways can be conducted in living humans because of the degree of invasiveness required to measure airway structural changes. These studies reveal that currently available agents do not fully prevent or reverse AWR. Thus, animal models of asthma pathology may be...
Pandey VS.The lungs and livers of 429 adult donkeys from different parts of Morocco were examined for hydatid cysts; 4·2% of lungs were infected and 2·1% of livers. Most of the cysts were small and had very hard thick walls; 61% of the donkeys had only one hydatid cyst; 78·5% of them were sterile and 29% caseated or calcified.
Pattle RE, Rossdale PD, Schock C, Creasey JM.The development of the lung from the glandular through the canalicular to the alveolar stages in the horse fetus is described. Traces of surfactant and occasional lamellated osmiophilic bodies representing intracellular surfactant were found at 150 days of gestation, some 40 to 60 days before the transition to the canalicular stage. During this transition some of the cuboidal cells of the glandular rosettes are transformed into cells of Types I and II, but the surfactant is not fully developed until 300 days or, in some foals, until after delivery.
O'Callaghan MW, Pascoe JR, Tyler WS, Mason DK.The purpose of this study was to use radiographic contrast techniques and special imaging methods to identify and high-light bronchial arterial involvement in lung lesions associated with exercise-induced pulmonary haemorrhage (EIPH) in horses. The lungs from four horses with histories of EIPH were prepared for computerised tomographic scanning and microradiography by perfusing the broncho-oesophageal artery with a mixture of red latex and either barium or iodine contrast materials while the pulmonary supply received only blue latex. Computerised tomographic scan slices of the prepared inflate...
Bizzotto D, Paganini S, Stucchi L, Avallone MP, Ramirez EM, Pompilio PP, Ferrucci F, Lavoie JP, Dellacà RL.. 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.. 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 appr...
Kutasi O, Horvath A, Harnos A, Szenci O.We characterized the kinetics of postnatal equine lung using sequential thoracic radiography. The aim was to establish the earliest time when normal foals have clear, radiolucent lung fields, and to characterize the pattern of this clearance. Both right-to-left and left-to-right thoracic radiographs were acquired in lateral recumbency at peak inspiration within the first 30 min after birth and thereafter at 1, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h. Radiographs were interpreted by three observers. The overall assessment of radiographic lung clearance was followed by the evaluation of individual l...
Wilson DV, Schott HC, Robinson NE, Berney CE, Eberhart SW.Guidelines for administration of oxygen to standing horses are unavailable because previous investigations of the efficacy of oxygen administration to increase arterial oxygenation in standing horses have produced equivocal results. Objective: To determine the effect of nasal oxygen supplementation on inspired and arterial blood gas tensions in control horses and those with moderate to severe recurrent airway obstruction (RAO). Methods: Normal horses (n = 6) and horses during an attack of RAO induced by stabling (n = 6) were studied. Oxygen was administered through either one or 2 cannulae, pa...