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.
Scarratt WK, Crisman MV.Tumors of the equine respiratory tract occur infrequently. An accurate diagnosis of neoplasia of the respiratory tract is critical because the prognosis is usually grave. The clinical signs and diagnostic procedures are discussed for tumors of the nasal and paranasal sinuses, nasopharynx/larynx, guttural pouch and thorax including lung, pleura, and thymus.
Nelson KM, Schram BR, McGregor MW, Sheoran AS, Olsen CW, Lunn DP.Inactivated alum-adjuvanted conventional equine influenza virus vaccines are of poor efficacy and offer limited short-term protection against infection. In sharp contrast, natural infection with equine influenza virus confers long-term protective immunity. In order to identify the protective immune responses to equine influenza virus, the influenza virus-specific IgA, IgGa, IgGb, IgGc and IgG(T) antibody responses in nasal secretions and serum induced by natural infection and a commercial vaccine were studied by ELISA. Two groups of four influenza-naive ponies were established. In the natural ...
Walker MA, Schumacher J, Schmitz DG, McMullen WC, Ruoff WW, Crabill MR, Hawkins JF, Hogan PM, McClure SR, Vacek JR, Edwards JF, Helman RG, Frelier PF.Three adult horses underwent aggressive treatment of squamous cell carcinoma of the nasal cavity and paranasal sinuses, using course-fractionated cobalt 60 radiotherapy. Squamous cell carcinoma of the nasal cavity and paranasal sinuses is not commonly diagnosed in horses. Historically, horses with this type of neoplasm have not been treated or have undergone some form of surgery. The prognosis for long-term survival or cure has been poor. Long-term results of cobalt 60 radiotherapy were good to excellent and exceeded those usually reported for horses treated surgically. On the basis of these r...
Traub-Dargatz J.This article describes the field investigation of horses with nasal discharge (serous, purulent, blood and feed). Flow charts on how to evaluate affected horses, and photographs of the examination procedures and of horses affected with nasal discharge are included.
O'Brien RT, Biller DS.This article addresses the current status and clinical opportunities for portable radiography and ultrasonography. Radiology is indicated for imaging the nasal cavity, larynx, pharynx and thin portions of the neck. In young foals, adequate radiographs of the entire respiratory tract may be possible. Ultrasonography is indicated in superficial parts of the head and neck, the pleural space and diseased parts of the lungfields.
Yarbrough TB, Carr EA, Snyder JR, Hornof WJ.This article reports an alternative to septal resection in nasal septal deviations involving the rostral 7 to 10 cm of the nasal septum. Methods: Case report. Methods: One client-owned foal. Methods: A nasal approach with mucosal elevation was used to gain access to the cartilaginous portion of the nasal septum. Once exposed, a series of parasagittal incisions in the cartilage allowed the septum to be repositioned while providing some intrinsic stabilization. Results: The nasal approach provided good access to the rostral 7 cm of the nasal septum. The technique resulted in minimal hemorrhage f...
Theoret CL, Grahn BH, Fretz PB.Atresia of the nasal punctum is the most common congenital anomaly for the equine nasolacrimal system. Nasomaxillary dysplasia has not been previously documented in foals, is of unknown etiology, and appears to be a rare condition. Conjunctivomaxillary sinostomy was successful in resolving the epiphora.
Tomasic M, Mann LS, Soma LR.To determine the effects of endotracheal intubation on respiratory mechanics during xylazine sedation and xylazine-diazepam-ketamine anesthesia in adult horses. Methods: 5 healthy adult horses. Methods: Measurements were derived from recordings of respiratory gas flow, and transpulmonary and transtracheal pressures. Total pulmonary resistance (RT) was partitioned into upper airway resistance (extrathoracic portion of trachea, larynx, pharynx, nasal cavity, nares; RUA) and lower airway resistance (intrathoracic portion of trachea, bronchi, bronchioles). Baseline measurements were obtained in un...
Watt BC, Beck BE.Diagnosis and removal of a nasal polyp in a horse using standing chemical restraint and readily available equipment are described. Histopathology of the polyp and differential diagnoses are discussed.
Clarke CJ, Roeder PL, Dixon PM.A severe, advanced case of nutritional osteodystrophia fibrosa is described in a 10-year-old gelding with primary upper respiratory obstruction and chronic weight loss, which was one of a group of similarly affected horses in Ethiopia. The diagnosis was based on the clinical signs, gross lesions, histopathology and management history. The affected bones had suffered severe mineral depletion.
van Maanen C, Klein WR, Dik KJ, van den Ingh TS.Three cases of carcinoid tumor in horses are described. The tumors originated from the maxillary sinuses and the retrobulbar region and caused exophthalmos. Histologically, they had a characteristic endocrine pattern and were argyrophilic with the Grimelius stain. All tumors contained reactivity for neuron-specific enolase and synaptophysin. Two of three tumors were reactive for both bovine and porcine chromogranin A. These immunohistochemical results confirm the neuroendocrine nature of these tumors. Neuroendocrine cells could not be detected in the nasal mucosa and maxillary sinuses of a nor...
Zamos DT, Schumacher J, Loy JK.Nasopharyngeal conidiobolomycosis caused by Conidiobolus coronatus was diagnosed in a horse after endoscopic and histopathologic examinations of a biopsy specimen. The fungal lesions in the nasopharynx were substantially reduced in size after intralesional injection of amphotericin B through the biopsy channel of a videoendoscope in combination with i.v. administration of sodium iodide and oral administration of potassium iodide during a 2-month period. Endoscopy performed 15 months after initial examination revealed regression of the granulomatous masses in the nasopharynx and complete disapp...
Hogan PM, Embertson RM, Hunt RJ.A 4-month-old Thoroughbred foal was examined because of a history of exercise intolerance and lack of airflow from the right nostril since birth. Endoscopy of the airways revealed complete membranous obstruction of the right nasal passage at the level of the nasopharynx and marked narrowing of the caudal aspect of the right ventral meatus. Unilateral choanal atresia was diagnosed. Laser ablation of the obstructing tissues was attempted through a videoendoscope. Scar tissue occluded the right nasal passage at follow-up examination 7 weeks later. Intranasal resection, using laparoscopic instrume...
Gosztonyi G, Ludwig H.Natural BD is a nonpurulent acute/subacute encephalitis of horses and sheep with a propensity to involve the olfactory and limbic systems, and the brain stem. The inflammation is concentrated primarily in the gray matter, but subcortical white matter may also be affected. Experimental BD can be produced in a series of animals from birds to primates. The neuropathology after experimental infection is similar to that in natural disease but the inflammatory changes are more diffuse. In the rat and mouse, a persistent/tolerant infection can also be induced, in which inflammatory changes are conspi...
King CM, Evans DL, Rose RJ.A standardised incremental exercise test was performed by 9 racehorses with idiopathic laryngeal hemiplegia (ILH), 1 horse with maxillary sinus cysts, 1 horse with epiglottic entrapment, 1 horse with a lesion on the vocal folds, and 1 horse with pharyngitis. Two of the horses with ILH were retested after laryngoplasty and ventriculectomy. The findings were compared with those from 20 normal racehorses. Heart rate, plasma lactate concentration, arterial blood gases, stride frequency, oxygen uptake (VO2) and carbon dioxide production were assessed during treadmill exercise on a +10% slope. The g...
Gilkerson J, Jorm LR, Love DN, Lawrence GL, Whalley JM.Equid herpesvirus-4 (EHV-4) was detected in nasal swabs taken from foals using a PCR based test and this information used to study the epidemiology of EHV-4 disease on three Australian Thoroughbred stud farms in NSW in 1992. There was a very high level of agreement (kappa value of 0.84) between the PCR results and virus isolation using cell culture techniques. There was a strong seasonal distribution of EHV-4 shedding. Twenty-five of 26 positive samples were collected in January and March with the remaining positive sample collected in February. Foals with clinical signs of upper respiratory t...
Adair HS, Duncan RB, Toal RL.A 3-year-old Appaloosa stallion with a 4 cm x 4 cm x 2.5 cm mass protruding from his nasal bone was evaluated. Radiographs revealed an osseous mass, with a radiopaque outer margin and several radiolucent areas within the body of the mass. The mass was surgically removed and evaluated histopathologically. The histopathological diagnosis was osteochondroma. This case represent the first reported occurrence of an osteochondroma arising from intramembraneous bone in the horse.
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.
Zaruby JF, Livesey MA, Percy DH.This clinical report describes an 8-year-old Thoroughbred mare that was presented for evaluation of a chronic, unilateral nasal discharge. Findings on physical examination, radiology, and video-endoscopy supported a clinical diagnosis of ethmoidal hematoma. After surgical ablation of the mass a defect was detected in the cribriform plate. At necropsy a 1.5 cm aperture was identified in the left cribriform plate allowing direct communication between the fundus of the nasal cavity and the cranium. Histology of the mass identified tissue consistent with an adenocarcinoma. History of profuse epist...
Hanson PD, Frisbie DD, Dubielzig RR, Markel MD.A 5-year-old Quarter Horse mare was examined because of a 6-month history of quidding and nasal discharge that contained feed material. Physical examination revealed weight loss and dorsal displacement of the soft palate, caused by a soft tissue mass located at the dorsal aspect of the base of the tongue. Surgical resection of the mass was successfully performed through an oral approach. The histopathologic diagnosis was rhabdomyosarcoma.
Hance SR, Bertone AL.Equine tumors are rather uncommon; however, of the body regions, the head is a relatively common location for neoplasia, including sarcoids and squamous cell carcinomas of the skin, tumors of the sinus/nasal cavity, and bony tumors of the head. Tumors discussed in the article include odontogenic and bony tumors; sarcoids; tumors of the guttural pouch and pharyngeal and oral mucosa; tumors of the larynx; and tumors of the paranasal sinuses and nasal passages. In general, tumors involving deeper structures of the head carry a poor prognosis; however, some tumors such as sarcoids, ossifying fibro...
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.
Knottenbelt DC.Twenty-four foals were confirmed to be infected with Rhodococcus equi on a private stud in Zimbabwe over a two-year period. Six mares had foals which were affected in each of the two years. All the foals were febrile and early cases were detected by this pyrexia. Bronchopneumonia was only clinically detectable in advanced cases. In spite of energetic hygiene measures relating to pasture and housing management, the incidence was higher in the second year (23 per cent of foals born) than in the first (15 per cent of foals born). The mean age of the foals was significantly greater in the second y...
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...
Mair TS, Wills JM.Nasal and conjunctival swabs were obtained from 300 horses and Chlamydia psittaci was isolated from 15 of them (5 per cent). Eleven nasal swabs and six conjunctival swabs were positive on culture, but there was no association between the isolation of the organism and the presence of clinical ocular or respiratory disease. Six ponies were challenged with an equine isolate of C psittaci into the eye, nasal cavity or bronchial tree. The organism could be isolated from nasal and conjunctival swabs taken from the ponies for up to 17 days after challenge, but there was no clinical evidence of diseas...
Orsini PG, Ross MW, Hamir AN.The ventral part of the levator nasolabialis muscle was transposed to the alveolar defect after sinusotomy and tooth extraction in five normal horses and six horses with a tooth root abscess and sinusitis. In the normal horses at weeks 6, 10, 14 and 18, the transposed muscles remained viable and were incorporated into the recipient sites, and orosinus fistulae did not form. Histologically, there was a progressive transition from muscle to fibrous tissue. There was no facial deformity or loss of nasal function at the donor site. A localized abscess was associated with incomplete removal of toot...
Kamada M, Kumanomido T, Wada R, Fukunaga Y, Imagawa H, Sugiura T.Aerosol transmission in equine Getah virus (GV) infection was examined by intranasal inoculation with 10(3.0) to 10(7.0) TCID50 of the MI-110 strain in 7 experimental horses. The establishment of intranasal infection of GV was confirmed in all these horses by detecting serum neutralizing antibody against the MI-110 strain. Horses inoculated with more than 10(4.0) TCID50 of the virus manifested mild pyrexia, eruptions, serous nasal discharge, lymphopenia or monocytosis. Viremia ranging from 10(1.0) to 10(3.5) TCID50/0.2 ml occurred in horses inoculated with 10(5.0) TCID50, or more. Virus recove...
Fey K.Horses are obligate nasal breathers and depend on patency of their nasal passages. Several dynamic obstructive diseases in the pharyngeal and laryngeal area can be differentiated by high speed treadmill endoscopy and may be responsible for impaired exercise tolerance in the equine athlete. The anatomical specialty of guttural pouches predisposes the horse to species-specific diseases.
Robert MP, Stemmet GP, Smit Y.Bilateral paranasal sinus diseases are rarely reported in horses. Treatment using a bilateral frontonasal bone flap on a standing, regular-sized adult horse has not been described previously. A 13-year-old Thoroughbred gelding was evaluated for bilateral mucopurulent nasal discharge. Radiographic, endoscopic and computed tomographic examinations revealed bilateral sinus pathological changes consistent with an ethmoid haematoma involving the maxillary and frontal sinuses. A bilateral frontonasal bone flap was created under standing sedation and local anaesthesia. A tracheotomy was performed ini...
Lane JG, Gibbs C, Meynink SE, Steele FC.The radiographic procedures used for examination of the facial area and paranasal sinuses of 235 horses are reported. Clinical indications for these examinations and the diagnoses made are reviewed. Unilateral nasal discharge was the commonest reason for radiography, accounting for about one third of cases, most of which had radiological signs of paranasal sinus disease recognisable on erect lateral films. Oblique projections were required to obtain further information about the maxillary dental arcades and ventro-dorsal views demonstrated sinus expansion and extension of disease into the nasa...
Holcombe SJ, Berney C, Cornelisse CJ, Derksen FJ, Robinson NE.To determine the effect of a commercially available nasal strip on airway mechanics in exercising horses. Methods: 6 horses (5 Standardbreds and 1 Thoroughbred). Methods: Horses exercised on a treadmill at speeds corresponding to 100 and 120% of maximal heart rate with and without application of a commercially available nasal strip. Concurrently, tracheal pressures, airflow, and heart rate were measured. Peak inspiratory and expiratory tracheal pressures, airflow, respiratory frequency, and tidal volume were recorded. Inspiratory and expiratory airway resistances were calculated by dividing pe...
Norman TE, Chaffin MK, Bisset WT, Thompson JA.To characterize the associations between clinical signs of nasopharyngeal cicatrix syndrome (NCS) and endoscopic findings in horses. Methods: Retrospective, case-control study. Methods: 239 horses (118 case horses and 121 control horses). Methods: Medical records of horses that had an endoscopic evaluation of the upper airway performed between January 2003 and December 2008 were reviewed. Clinical signs and the appearance and anatomic locations of lesions identified during endoscopic evaluation were reviewed and recorded for each horse. The associations between clinical signs and endoscopic fi...
Palozzo A, Celani G, Varasano V, Marruchella G, Petrizzi L.Equine sinonasal myxomas (SNM) are very rare; only a few cases/small case series are reported in veterinary literature. The purpose of this report is to describe the diagnostic and surgical procedure adopted to approach the neoplastic mass in a case of equine SNM. A 5 year old, Murgese gelding was presented with mild serous nasal discharge, minimal facial swelling, decreased airflow from the right nostril, and dull frontal sinus percussion. Diagnostic imaging, including endoscopy, revealed a pale mass in the caudal portion of the right middle meatus, which developed inside the right conchofron...
Rodríguez N, Whitfield-Cargile CM, Chamoun-Emanuelli AM, Hildreth E, Jordan W, Coleman MC.The nasopharyngeal bacterial and fungal microbiota of normal horses and those with nasopharyngeal cicatrix syndrome (NCS) are unknown. Objective: To describe the microbiota from nasopharyngeal washes of healthy horses and of horses acutely affected with NCS. Methods: Twenty-six horses acutely affected with NCS horses and 14 unaffected horses. Methods: Prospective, observational cohort study. Horses were recruited by investigators through personal communications in central Texas. Bacterial (16s RNA) and fungal (internal transcribed spacer) microbiota from nasopharyngeal washes were evaluated. P...
Davis PR, Meyer GA, Hanson RR, Stringfellow JS.An 18-year-old 454-kg (1,000-lb) American Quarter Horse gelding was evaluated because of chronic intermittent malodorous right-sided nasal discharge. Endoscopy revealed a mycotic plaque in the nasal cavity adjacent to the nasomaxillary opening of the right caudal maxillary sinus. The nasomaxillary opening appeared to be larger than normal. Fungal culture of specimens of the mycotic plaque yielded Pseudallescheria boydii. The horse was treated with 2% miconazole intranasally, sodium iodide i.v., and potassium iodide p.o. Thirty and 60 days after treatment was initiated, the nasal cavity was fou...
Pusterla N, Chaney KP, Maes R, Wise AG, Holland R, Schott HC.The objective of this study was to investigate whether intramuscular vaccination of healthy adult horses with a killed or a modified live equine herpesvirus type 1 (EHV-1) vaccine could induce transient positive PCR results in either blood or secretions collected on a nasopharyngeal swab. Four horses in each group received either a single killed or a modified-live vaccine intramuscularly. Two local commingled and 2 distant nonvaccinated controls were included for each group. All horses were observed daily for evidence of clinical abnormalities throughout the study periods. Blood and nasopharyn...
Hogan PM, Embertson RM, Hunt RJ.A 4-month-old Thoroughbred foal was examined because of a history of exercise intolerance and lack of airflow from the right nostril since birth. Endoscopy of the airways revealed complete membranous obstruction of the right nasal passage at the level of the nasopharynx and marked narrowing of the caudal aspect of the right ventral meatus. Unilateral choanal atresia was diagnosed. Laser ablation of the obstructing tissues was attempted through a videoendoscope. Scar tissue occluded the right nasal passage at follow-up examination 7 weeks later. Intranasal resection, using laparoscopic instrume...
Dirikolu L, Mollett BA, Troppmann A, Woods WE, Bratton C, Cashman CP, Schroedter D, Mayer B, Lehner AF, Karpiesiuk W, Hughes C, Boyles J, Harkins JD....Single doses of one, three, and six actuations (120 micro g albuterol/actuation) and multiple daily doses (six actuations per dose four times daily) for 5 days of aerosol albuterol sulfate were sequentially administered to each of six horses using an equine inhaler device (Torpex, 3M Animal Care Products, St. Paul, MN [corrected] and Boehringer Ingleheim Vetmedica, Inc., St. Joseph, MO [corrected]). A 2-week washout period was allowed between each dose. ELISA testing revealed no evidence of albuterol in urine at 24 hours after any single-dose administration. Results indicated that 48 hours or ...
Orsini PG, Ross MW, Hamir AN.The ventral part of the levator nasolabialis muscle was transposed to the alveolar defect after sinusotomy and tooth extraction in five normal horses and six horses with a tooth root abscess and sinusitis. In the normal horses at weeks 6, 10, 14 and 18, the transposed muscles remained viable and were incorporated into the recipient sites, and orosinus fistulae did not form. Histologically, there was a progressive transition from muscle to fibrous tissue. There was no facial deformity or loss of nasal function at the donor site. A localized abscess was associated with incomplete removal of toot...
de Mira MC, Ragle CA, Gablehouse KB, Tucker RL.A 3-year-old Thoroughbred mare was evaluated because of abnormal upper respiratory tract sounds (that had become apparent during race training) of 3 to 4 months' duration. Results: On initial physical evaluation, there were no abnormal findings. During trotting, an abnormal upper airway expiratory sound was audible. Endoscopic examination revealed a small mass protruding into the right ventral nasal meatus. Radiographic images of the skull revealed no abnormal findings. Computed tomography of the head revealed an abnormal structure in the same location as the mass that was observed during endo...
Milillo P, Traversa D, Elia G, Otranto D.Larvae of Rhinoestrus spp. (Diptera, Oestridae) infect nasal and sinus cavities of horses, causing a nasal myiasis characterized by severe respiratory distress. Presently, the diagnosis of horse nasal botfly relies on the observation of clinical signs, on the post mortem retrieval of larvae or on molecular assays performed using pharyngeal swabs. The present study was carried out to characterize larval somatic proteins and salivary glands of Rhinoestrus spp. in a preliminary assessment towards the immunodiagnosis of equine rhinoestrosis. Out of the 212 necropsied horses 13 were positive for th...
Buchalski FM, Rankins EM, Malinowski K, McKeever KH.The purpose of this study was to examine the effects of an external nasal strip on thermoregulation during submaximal exercise in Standardbred horses. While several studies have been conducted to determine the effects of the external nasal strip on airway resistance, exercise induced pulmonary hemorrhage, gas exchange, and time to fatigue in maximally exercising horses, the effects of the nasal strip on equine thermoregulation have not yet been examined. It was hypothesized that the application of an external nasal strip would alter central venous temperature (T), skin temperature (T), and exe...
Stoppini R, Tassan S, Barachetti L.An 8-year-old Hanoverian mare was presented for chronic mucopurulent discharge in the left eye, which was responsive to topical antibiotic therapy. Results: The nasolacrimal orifice was absent in the left nasal meatum, and anterograde irrigation of left nasolacrimal duct was not possible. Dacryocystorhinography was performed and revealed about 4-6 cm of distal nasolacrimal duct atresia. Unassigned: A novel technique was attempted with the horse under standing sedation using an urinary catheter and a 980 nm diode laser with a 600 μm diameter flexible bare quartz fiber. A nasolacrimal orifice w...
Perez JA, Hutton AE, Cudd SK, Brown JA.To describe a novel standing trans-nasal endoscopic guided CO2 laser fenestration approach to access the sphenopalatine sinus (SPS) in the horse. Methods: Case report. Methods: Cadaver study and client-owned 20-year-old Warmblood gelding. Methods: The rostral palatine bone within the nasopharynx was investigated as a possible site for fenestration to access the SPS in cadavers. The ability to fenestrate the SPS was tested in cadavers using a flexible endoscope and CO2 laser fiber inserted via biopsy channel. The fenestration procedure was then performed in a clinical case presented for unilate...
Hashikura S, Higuchi T, Taharaguchi S, Orita Y, Nanao Y, Takai S.The reliability of preparing bacteriological cultures from nasotracheal aspirates of foals routinely in order to diagnose R. equi pneumonia in foals was studied by isolating Rhodococcus equi from specimens obtained from 96 foals by nasotracheal aspiration with a silicon catheter. Results were compared with specimens obtained from 21 foals by transtracheal aspiration (percutaneous tracheal puncture). These 117 foals showed clinical signs of respiratory tract infection at sampling. R. equi was isolated from 14 of 21 (66.7%) specimens by transtracheal aspiration and from 59 of 96 (61.4%) specimen...
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...
Legere RM, Wooldridge AA, Sandey M, Hanson RR, Cole R.This case represents the first reported case of Bipolaris hawaiiensis infection in an equid, and its aggressive clinical course. This case provides important descriptive and prognostic information for horses diagnosed with phaeohyphomycotic rhinitis. A 19-year-old American Quarter Horse mare was presented for second opinion of stertor and exercise intolerance of four-month duration. Endoscopy revealed generalized, proximal nasal edema, and computed tomography identified a soft tissue mass eroded through the rostral nasal bone. Biopsy of the mass was identified as a fungal granuloma caused by B...
Schaaf KL, Kannegieter NJ, Lovell DK.A Warmblood horse presented with a purulent nasal discharge that had failed to respond to antibiotic therapy. Radiography and endoscopy confirmed a large number of chondroid masses (over 200) in the left guttural pouch. Despite the large number of chondroids present, there was no external swelling evident. The masses were surgically removed via a hyovertebrotomy approach that provided excellent exposure, and no postoperative complications were encountered. Long term follow-up (3 years) confirmed a successful outcome.
Knottenbelt DC.Twenty-four foals were confirmed to be infected with Rhodococcus equi on a private stud in Zimbabwe over a two-year period. Six mares had foals which were affected in each of the two years. All the foals were febrile and early cases were detected by this pyrexia. Bronchopneumonia was only clinically detectable in advanced cases. In spite of energetic hygiene measures relating to pasture and housing management, the incidence was higher in the second year (23 per cent of foals born) than in the first (15 per cent of foals born). The mean age of the foals was significantly greater in the second y...
Corcoran BM, Mayhew IG, Hahn CN, Prince DR.To determine the distribution of nerve fibers containing calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP), and intermediate neurofilaments in nasal mucosa of horses. Methods: 6 horses without evidence of nasal disease. Methods: Full-thickness nasal tissue specimens were obtained from the rostral portion of the nasal septum at necropsy, and fluorescence immunohistochemistry was performed to assess mucosal distribution of nerve fibers. Results: Nerve fibers with CGRP-like immunoreactivity (CGRP-Li) formed a dense subepithelial network, and a large num...
Mitlehner A, Mitlehner C, Reißmann M, Stoll P, Swoboda I, Mitlehner W.American Bashkir Curly Horses are claimed to be hypoallergenic, but this has not been clinically proven. In the present study, the effect of exposure to Curly Horses was investigated in 141 patients allergic to horses by measuring their lung function and nasal patency during Curly Horse contact. Continuous contact with Curly Horses, including riding and brushing, decreased the allergic riders' reactivity as measured by FEV1, PEF, and PNIF. Subsequent visits (up to 40 or more hours of riding) further reduced reactivity to the Curly Horses. Allergic events to horses occurred only in 72 out of 13...
Alhaddad H, Powell BB, Pinto LD, Sutter N, Brooks SA, Alhajeri BH.Horse traits under selection are largely quantitative and affected by multiple genes. Horse face shape is an example of a continuous trait, which due to the reliance on observational assessments, is classified into; "dished", "straight", and "roman-nosed". This categorization is often inadequate to convey the full spectrum of the face shape variation especially for genetic studies. The first objective of the current study was to use geometric morphometric methods to quantitatively phenotype face shapes and examine its variation across horse breeds. The second objective was to analyze the face ...
Kloock T, Hellige M, Kloock A, Feige K, Niebuhr T.Horses with trigeminal-mediated headshaking (TMHS) exhibit different headshaking patterns (HSPs), electric shock-like jerking, signs of nasal irritation, and painful facial expressions. The History Rest and Exercise Score (HRE-S) was developed to objectively clarify the severity of the condition in affected horses. This score considers the history and severity of clinical signs at rest and exercise. This study aimed to assess the frequency of different clinical signs and their individual associations with diagnosis, treatment, and outcome in horses diagnosed with TMHS.The clinical records of h...
Bishop RC, Migliorisi A, Holmes JR, Kemper AM, Band M, Austin S, Aldridge B, Wilkins PA.Understanding normal microbial populations within areas of the respiratory tract is essential, as variable regional conditions create different niches for microbial flora, and proliferation of commensal microbes likely contributes to clinical respiratory disease. The objective was to describe microbial population variability between respiratory tract locations in healthy horses. Samples were collected from four healthy adult horses by nasopharyngeal lavage (NPL), transtracheal aspirate (TTA), and bronchoalveolar lavage (BAL) of six distinct regions within the lung. Full-length 16S ribosomal DN...
Allano M, Arsenault J, Archambault M, Fairbrother JH, Sauvé F.Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of nosocomial infections, including in veterinary settings. Objective: To investigate the prevalence, risk factors for Staphylococcus aureus (SA) and MRSA colonization, and the duration of MRSA colonization. Methods: Elective cases admitted to the Veterinary Teaching Hospital were recruited (228 horses). Methods: A cross-sectional study was conducted over 3 years. Nasal swabs were collected at admission and cultured for SA. Methicillin-resistant isolates were identified using matrix-assisted laser desorption/ionization-time-...
