The nasal cavity in horses is a complex anatomical structure that plays a significant role in respiration and olfaction. It consists of a series of passages lined with mucous membranes and cilia that filter, humidify, and warm the air before it reaches the lungs. The nasal cavity is also involved in vocalization and serves as a conduit for pheromonal communication. Various conditions can affect the equine nasal cavity, including infections, allergies, and structural abnormalities, which can impact a horse's respiratory efficiency and overall health. This page compiles peer-reviewed research studies and scholarly articles that explore the anatomy, physiology, and pathologies associated with the nasal cavity in horses, as well as diagnostic and therapeutic approaches.
Mason TA.Two cases of bilateral atresia of the nasolacrimal orifice are described. The presenting sign was a persistent ocular discharge, clear in the one case and purulent in the other. Treatment by the creation of a fistula between the distal extremity of the blind ending duct and the nasal cavity was successful in both cases.
Valdez H, McMullan WC, Hobson HP, Hanselka DV.A 6-month-old Appaloosa colt had a deviation of the premaxilla and nasal septum as well as a dorsal hump of the nasal bone and maxillomandibular malocclusion. Two surgical procedures were performed 12 weeks apart to correct these anomalies. An intraoral approach and autogenous rib graft were used to correct the malocclusion and deviation of the premaxilla. Osteotomy of the nasal bone and removal of the nasal septum were performed to help correct the deviation and to facilitate free air passage through the nares.
Rawlinson RJ, Jones RT.The history and clinical findings of 1 horses with guttural pouch mycosis referred to us are described. The salient features of the history and clinical signs common to both cases were profuse spontaneous nasal haemorrhage, partial pharyngeal paralysis; subsequently bilateral nasal discharge containing food material, inability to drink and parotid pain became evident. One case made a gradual recovery with conservative medical treatment while the second case was destroyed and submitted for post-mortem, histopathological and microbiological examination. This examination failed to establish the i...
Moorthy AR, Spradbrow PB.Two strains of Chlamydia psittaci were isolated from the nasal tract of horses with acute respiratory disease. These 2 isolates (NS 121 and NS 172) were characterized as chlamydia on the basis of their morphology, tinctorial property, growth in chicken embryos, inability to grow on bacterial media and their possession of chlamydial common complement fixing group antigen. They were identified as C. psittaci on the basis of resistance to sodium sulphadiazine. The present strains were not pathogenic to mice and guinea pigs and non-toxigenic. They induced antibodies and caused latent infection in ...
Cook WR.Broken wind is a syndrome characterised by chronic bronchitis and alveolar emphysema. Clinical signs include nasal catarrh, persistent coughing, dyspnoea and poor exercise tolerance. In racehorses, lung haemorrhages may result in epistaxis. Broken wind is a disease of domestication ascribed to pollution of the stable air with fungal spores from hay and straw. Treatment and prevention are based on the provision of fresh air and, if housing is unavoidable, the adoption of a permanent regime of dust-free stable management. If an early diagnosis is made and appropriate treatment instituted, the pr...
Cannon JH, Grant BD, Sande RD.Development of cysts in the equine paranasal sinuses is probably a congenital disease; however, signs may not appear for several years. In 4 cases, clinical signs were observed when fluid accumulation within the cysts resulted in nasal discharge or facial swelling, or when secondary infection occurred. Treatment required surgical removal of the lining membrane and other involved tissues. Postoperative care included lavage of the sinuses and systemic antibiotic therapy.
Moorthy AR, Spradbrow PB.Mycoplasmas were isolated from two of 43 nasal swabs taken from live horses, and from one of 28 tracheal swabs taken from slaughtered horses. The slaughtered horse that yielded mycoplasmas had no gross pathological changes in the respiratory tract, but the nasal isolations were made from horses with rhinitis. The three mycoplasmas could be distinguished by cultural characteristics, and probably they represent three different species.
Mason BJ.A case of spindle cell sarcoma of the equine para-nasal sinuses is described and discussd in relation to similar tumours recorded in the literature.
Platt H.A series of 10 haemorrhagic polyps of the equine nasal cavity is described. The lesions show haematoma formation, abundant haemosiderin in macrophages and giant cells, and organising fibrous tissue. In one case, angiomatoid lesions were observed in the mucous membrane of the paranasal sinuses and it is suggested that some haemorrhagic nasal polyps may originate from pre-existing haemangiomatous areas in the respiratory mucosa.
Woolcock JB.Equine tonsillar tissue and the draining regional lymph nodes, as well as deep nasal swabs were examined bacteriologically. Group C streptococci, predominantly Streptococcus zooepidemicus, were shown to be present in all tissues. The most frequent site for isolation was the tonsil. Streptococcus equi was not located in any of the tissues sampled.
Doyle AJ, Freeman DE.To describe a surgical technique for, and report outcome after, extensive nasal septum resection in horses with congenital or acquired septal diseases. Methods: Retrospective study. Methods: Horses (5) with nasal septal deformity. Methods: Under general anesthesia, obstetrical wires were preplaced around the ventral, caudal, and dorsal aspects of the nasal septum by combinations of manual guidance (ventral and caudal wires) and use of a trephine hole on the dorsal mid-line (dorsal and caudal wires). The rostral part of the septum was incised with a scalpel and the ventral, dorsal, and caudal s...
Schumacher J, Hanselka DV.Nasopharyngeal cicatrices were observed endoscopically in 47 horses examined because of abnormal respiratory noises and/or exercise intolerance. A review of these cases revealed a correlation between cicatrization and age, sex, and the presence of other upper airway abnormalities. The age of affected horses ranged from 6 to 21 years, with a mean age of 12.7 +/- 7.8 (+/- 2 SD) years. Females were affected 2.7 times more frequently than males. Abnormalities commonly observed with a nasopharyngeal cicatrix included chondritis of the arytenoid cartilage, epiglottic deformity, and deformity of the ...
Haynes PF.The intent and extent of the respiratory tract examination relevant to purchase are dictated by numerous factors, including historical information, signs suggestive of respiratory tract abnormalities, intended use of the horse, and economic considerations. Following a thorough and systematic examination of the horse at rest, evaluation during and following exercise may be warranted. The physical examination should include evaluation of regional symmetry of the head, neck, and thorax; evaluation of nasal airflow and patency; palpation of the nasal septum, larynx, and trachea; examination for su...
Froydenlund TJ, Dixon PM, Smith SH, Reardon RJ.The morphology of the dorsal (DCB) and ventral (VCB) nasal conchal bullae, including their cellulae, drainage and histology, are poorly described. The recent recognition that these bullae can become infected, causing chronic unilateral nasal discharge has stimulated interest in these structures. A more complete understanding of their anatomy would be useful in the diagnosis and treatment of their disorders. Objective: To document the structure, drainage and histology of the equine DCB and VCB. Methods: Descriptive. Methods: Fourteen fresh cadaveric horse heads, were transected sagittally midli...
Ratliff BL, Bauck AG, Roe HA, Freeman DE.To describe a 3-wire method with endoscopic guidance for extensive nasal septum resection. Methods: Retrospective study. Methods: Thirteen horses with nasal septum diseases. Methods: In anesthetized horses in left lateral recumbency, endoscopic guidance was used to place obstetrical wires for the ventral and caudal incisions in the nasal septum and a trephine opening was used to place the dorsal wire. The rostral aspect of the septum was incised with a scalpel, followed by incisions with the preplaced wires, and the nasal passages were packed with gauze. Horses were recovered with a temporary ...
Orr JA, Fraser DB, Shirer HW, Wagerle LC, DeSoignie RC.Carbon dioxide concentrations were increased during expiration in the upper one-half of the trachea, pharynx, and nasal sinuses to determine if elevation of upper airway CO2 would alter breathing or arterial blood gases in the awake pony. Carbon dioxide (100%) was injected into the midcervical trachea via a chronically implanted transcutaneous cannula during the first part of the animal's expiration. This maneuver elevated upper airway expiratory CO2 concentrations but prevented any exogenous CO2 from entering the lung and being absorbed into the arterial blood. Twelve experiments were perform...
Gordon D, Clark-Price S, Keating S, Schaeffer DJ, Lascola KM.This study evaluated the effects of various flow rates and fractions of oxygen on arterial blood gas parameters and on the fraction of inspired oxygen (FO) delivered to the distal trachea. Oxygen was administered to 6 healthy, conscious, standing, adult horses via single nasal cannula positioned within the nasopharynx. Three flow rates (5, 15, 30 L/min) and fractions of oxygen (21, 50, 100%) were delivered for 15 minutes, each in a randomized order. FO was measured at the level of the nares and distal trachea. Adverse reactions were not observed with any flow rate. FO (nares and trachea) and P...
van Nieuwstadt RA, Kalsbeek HC.In a horse with chronic unilateral nasal discharge guttural pouch mycosis caused by Aspergillus fumigatus was diagnosed. A percutaneous indwelling catheter was surgically installed in the left guttural pouch. Initial treatment with a povidone iodine solution proved to be unsatisfactory. Treatment was continued by administering enilconazole by ways of an indwelling through-the-nose-catheter. The latter treatment resulted in complete recovery.
Radcliffe RM, Messiaen Y, Irby NL, Divers TJ, Dewey CW, Mitchell KJ, Schnabel LV, Bezuidenhout AJ, Scrivani PV, Ducharme NG.To report a transnasal, endoscopically guided ventral surgical approach for accessing the cranial and caudal segments of the sphenopalatine sinus for mass removal in a horse. Methods: Case report. Methods: Adult horse with acute onset blindness referable to a soft tissue mass within the sphenopalatine sinus. Methods: A 7-year-old Warmblood gelding presented with a history of running into a fence and falling. No neurologic signs were identified at initial examination but acute blindness was noted 3 weeks later. On computed tomography (CT) the sphenopalatine sinus was filled with a large homogen...
Oakey J, Hawkesford T, Smith C, Hewitson G, Tolosa X, Wright L, Moody N, Rodwell B, Corney B, Waltisbuhl D.Describe the in-house validation of a previously reported influenza virus type A 5'Taq nuclease assay for detecting equine influenza virus A RNA in nasal swab material. Methods: The validation compares the 5'Taq nuclease assay with a gel-based reverse transcription nested polymerase chain reaction (PCR) previously reported by the Irish Equine Centre for detection of H3N8 and H7N7 equine influenza viruses. This test was chosen because it targets a different region of the viral genome to the real-time test, so it is not merely a repeat of the same test in a different format. Moreover, nested PCR...
Nickels FA.Conditions of this portion of the respiratory tract are relatively uncommon. This article reviews these conditions and discusses the different modes of therapy. The conditions covered are redundant alar folds, diseases of the nasal septum, fungal infections, neoplasms, nasal polyps, and ethmoid hematomas. The different surgical approaches to the nasal cavity are reviewed, and surgery of removal of the nasal septum and the alar fold are described.
Lores M, Yarbrough T.A 9-year-old pony gelding was evaluated because it was suspected that a persistent oronasal fistula had developed after a fractured right maxillary second premolar tooth had been extracted via repulsion 6 months earlier. Results: Unilateral mucopurulent nasal discharge and malodorous breath were noted on clinical examination. Examination of the oral cavity revealed a 1 × 0.5-cm defect at the oral aspect of the right maxillary second premolar alveolus, from which feed material was extracted. Endoscopic examination revealed feed material in the rostral aspect of the right nasal cavity, confirmi...
Gerard M, Pruitt A, Thrall DE.An aged pony with extensive paranasal sinus and nasal passage B-cell lymphoma was treated with palliative radiation therapy. Sixteen gray were administered in two fractions, 7 days apart. A lateral field was used for the first fraction and a dorsal field for the second. Because of tumor being present in the left frontal sinus, gross tumor was knowingly excluded from the treated volume in the lateral field. The tumor regressed within 2 months and the pony remained free of clinical disease for 2.5 years. Acute, temporary blindness developed shortly after the second radiation fraction, but a dire...
Espíndola JP, Machado G, Diehl GN, Dos Santos LC, de Vargas AC, Gressler LT.Microbiological diagnosis of equine respiratory infections is essential for disease management. However, reliable diagnosis can be a challenge due to colonization of the upper respiratory tract (URT) by a diverse microbial population, and because there is a lack of studies with samples from healthy animals. Aiming to guide adequate URT culture, this work reports culturable microbial population from the URT of 1,010 apparently healthy horses from 341 farms in Southern Brazil and identifies the putative presence of pathogenic microorganisms. Nasal swabs were cultured in 5% blood agar, and the is...
Vuerich M, Nannarone S.The aim of this study was to retrospectively report outcomes resulting from the approach to the maxillary nerve block (MNB) through the infraorbital canal, in terms of needles selection, drawbacks or side effects during or after block execution, and analgesic efficacy leading to clinical and cardiovascular stability during surgery. Anesthetic records of 15 horses undergoing orofacial surgery in standing analgo-sedation (STA, n = 6) and in general anesthesia (GEN, n = 9) were retrieved and analyzed. Horses in group STA required surgery for dental extraction, nasal polyp resection and maxillary/...
Zetterström S, Groover E, Lascola K, Cole R, Velloso A, Boone L.A five-year-old Thoroughbred mare was evaluated because of chronic, malodorous, unilateral nasal discharge, and suspected maxillary cheek tooth root abscess. Skull radiographs revealed bilateral sinusitis suspected secondary to tooth root abscessation of 109 and 210. Following oral extraction of 109, bilateral conchofrontal sinus trephination and lavage; fever, tachycardia, and cervical stiffness developed. A lumbosacral cerebrospinal fluid tap was performed, and a presumptive diagnosis of bacterial meningitis was made. Targeted therapy consisted of antibiotic treatment with penicillin, enrofl...
İncili CA, Eröksüz Y, Otlu B, Kara E, Tanrıverdi ES, Timurkan MÖ, Kalender H, Eröksüz H.Moellerella wisconsensis is a Gram-negative, facultative anaerobic bacillus of Entero-bacteriaceae family, and it is an uncommon pathogen in domestic animals. To date, five cases were reported including two dogs, two cattle, and a goat. Streptococcus equisimilis is the second common bacterial agent after the S. equi subsp. zooepidemicus in equine pneumonia cases. The present report describes the isolation of M. wisconses from lungs and spleen of a 10-year-old Arabian horse (May 08, 2022) at post-mortem examination being co-infected with S. equisimilis. Clinical and pathological findings includ...
Felici M, Cogger N, Nanni Costa L, Riley CB, Padalino B.Studies on equine air transport practices and consequences are scarce. This prospective study aimed to describe horse and air journey details and practices, document how horse behavior and health changed during the air transport phases, quantify the occurrence of welfare issues, and identify possible associations between horse and journey details, air transport practices, and welfare issues. Results: Data were collected from before departure to five days after arrival on 118/597 horses traveling on 32 commercial air journeys on different routes, varying in duration and conditions. Most horses ...
de Moura Alonso J, Watanabe MJ, de Moraes Gimenes Bosco S, Apolonio EVP, de Vasconcelos AB, do Prado AC, Alves ALG, Rodrigues CA, Hussni CA.Fungal rhinitis in horses is rare, although severe, due to the progressive nasal obstruction. Aspergillus is one of the fungi most often involved in these cases. A 7-year-old Quarter Horse mare weighing 325 kg was admitted with a history of recurrent nasal discharge and bleeding, foul smell, reluctance to exercise, and abortion. Laboratory and imaging examinations revealed eosinophilia, scarring and erosion areas in the nasal mucosa, purulent and bloody secretions, and remarkable yellowish plaques. Histopathological examination revealed fungal rhinitis and bacterial culture revealed the prese...
Cohen ND, Hughes EV, Bayne C, Morris ERA, Bray JM, Landrock KK, Gonzales DM, Baker RM, Klein RL, Liu W, Legere RM, Wehmeyer SG, Bordin AI....Evaluate the immunogenicity of a vaccine targeting the S protein (Ssee) of Streptococcus equi subsp equi and determine antibody activity against Ssee in horses with strangles. Methods: The study was designed as a prospective experiment using 20 university-owned Quarter Horses and a cross-sectional serosurvey of 78 privately owned horses with strangles. Horses were immunized IM with 0 (n = 4), 200 (n = 8), or 400 (n = 8) μg of recombinant Ssee at weeks 0, 4, and 12. Serum and nasal secretions were collected at weeks 0, 4, 6, 12, 16, and 28 and tested by ELISA for immunoglobulin (Ig)-G against ...
Cohen ND, Hughes EV, Bayne C, Morris ERA, Bray JM, Landrock KK, Gonzales DM, Baker RM, Klein RL, Liu W, Legere RM, Wehmeyer SG, Bordin AI....Evaluate the immunogenicity of a vaccine targeting the S protein (Ssee) of Streptococcus equi subsp equi and determine antibody activity against Ssee in horses with strangles. Methods: The study was designed as a prospective experiment using 20 university-owned Quarter Horses and a cross-sectional serosurvey of 78 privately owned horses with strangles. Horses were immunized IM with 0 (n = 4), 200 (n = 8), or 400 (n = 8) μg of recombinant Ssee at weeks 0, 4, and 12. Serum and nasal secretions were collected at weeks 0, 4, 6, 12, 16, and 28 and tested by ELISA for immunoglobulin (Ig)-G against ...
Pusterla N, Barnum S, Lawton K, Craig B, James K.Equid alphaherpesvirus 4 (EqAHV4; Orthoherpesviridae, Varicellovirus equidalpha4; equine rhinopneumonitis virus) has seldom been associated with complications such as abortion and myeloencephalopathy, given the low tendency of this virus to induce viremia. We investigated the frequency of EqAHV4 viremia in horses with fever and respiratory signs. Case selection included all equids with EqAHV4 quantitative real-time PCR (qPCR)-positive nasal secretions (defined as EqAHV4 qPCR-positive cases) submitted to a diagnostic laboratory. Controls consisted of each case submitted before and after each Eq...
Holley L, Creasey HN, Bedenice D, Reed S, Romualdo da Silva DR, Trautwein V, Mazan M, Widmer G.Glucocorticosteroids remain the most common pharmaceutical approach for the treatment of equine asthma but can be associated with significant side effects, including respiratory microbiome alterations. The goal of the study was to assess the impact of 2% lidocaine nebulization, a projected alternative treatment of equine asthma, on the healthy equine respiratory microbiota. A prospective, randomized, controlled, blinded, 2-way crossover study was performed, to assess the effect of 1 mg/kg 2% lidocaine (7 treatments over 4 days) on the equine respiratory microbiota compared to control horses (s...
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-...
Spadari A, Saragoni G, Meistro F, Ralletti MV, Marzari F, Rinnovati R.This case report documents an unusual cheek tooth (CT) displacement in a 3-year-old Arabian filly. The horse was referred to the clinic for loss of appetite and right-sided facial deformity. At admission, an oral inspection was performed, followed by a dental radiographic examination. The radiographs showed a very oblique vertical angulation (135°) of the CT 106 compared to the other premolars (107 and 108 CTs) (40°). In consideration of the clinical and radiographic findings, surgical extraction of the 106 CT was indicated. Due to the unique positioning of the displaced tooth, traditional e...
Schollmeyer M, Liebler-Tenorio EM, Felton C, Kohl S, Ulrich R.A 34-year-old Haflinger gelding presented with a unilateral, expansile, intranasal mass that regrew after partial excision. After euthanasia, a large pedunculated mass that originated from the left caudal maxillary sinus and obliterated the left nasal cavity was seen by radiological and macroscopic examination. Histopathology revealed a poorly cellular, expansile, well-vascularized neoplasm composed of a loosely arranged meshwork of spindle cells and collagen fibres. Spindle cells were immunopositive for alpha-smooth muscle actin and occasionally for vimentin, whereas endothelial cells immunol...
Kamutzki CJ, Emmerich IU.In 2024, there was no release of a novel pharmaceutical agent for horses and food-producing animals or an extension of existing active ingredients to other animal species on the German veterinary medicinal products market. Formic acid is now available for a new form of treatment, the short-term treatment of honeybees, and clenbuterol is available in a new dosage form, as an oral solution for horses. In the field of immunological veterinary medicinal products, three new vaccines were launched on the German veterinary medicinal products market. For the first time, a vaccine against in cattle, a...
Clarysse M, Korsos S, Vlaminck L.This case report presents the removal of the left maxillary fourth premolar tooth (208) which had a chronic complicated crown root fracture in a 9-year-old Warmblood mare. Following a 14-month history of malodorous nasal discharge, clinical and radiographic examination allowed the diagnosis of a comminuted crown root fracture of 208 and oronasal fistula. Some root fragments inaccessible for oral extraction were subsequently removed using a transnasal approach through the existing oronasal fistulous tract using bronchoesophageal forceps under endoscopic guidance. The oronasal fistula was surgic...
Mendes RP, Lima AE, da Cunha R, Bittar MJ, Vasconcelos CC, Piñeros DDV, Corrêa RR.Radiographic examination of the skull is a well-established and indispensable procedure for the diagnostic evaluation of dental and paranasal sinus disorders in horses. Complementary projections make significant contributions to radiographic diagnosis in nasal conchae disorders. This article describes a complementary radiographic projection designed for the evaluation of the conchal sinuses and bullae in horses. Six equine cadaveric heads were used. Specimens were dissected, and openings were created in the ventral and dorsal nasal conchae for the introduction of radiopaque material. The new r...
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...
