1
|
Lo Feudo CM, Stucchi L, Stancari G, Conturba B, Bozzola C, Zucca E, Ferrucci F. Associations between Medical Disorders and Racing Outcomes in Poorly Performing Standardbred Trotter Racehorses: A Retrospective Study. Animals (Basel) 2023; 13:2569. [PMID: 37627359 PMCID: PMC10451774 DOI: 10.3390/ani13162569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/13/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Poor performance in racehorses is commonly associated with subclinical diseases. This study aims to evaluate the associations between medical disorders and racing results in Standardbred trotters. The clinical records of 248 poorly performing Standardbreds were retrospectively reviewed, and their racing results were extracted from an online database, concerning the periods 3 months before and 6 months after hospitalization and the entire lifetime. Generalized linear models were used to evaluate the effects of different disorders on racing outcomes. Airway neutrophilia was associated with limiting lifetime starts and wins pre- and post-hospitalization, while mastocytosis was associated with less wins in the post-hospitalization period. Therefore, lower airway inflammation showed both short- and long-term impacts on racing performance. Severe upper airway obstructions and gastric ulcers showed associations with less placings in the post-discharge period but no long-term influence on performance. The significance of exertional rhabdomyolysis was indeterminable, yet interference with the number of starts in the post-discharge period was reported and associated with lower total career earnings. Exercise-induced pulmonary hemorrhage and cardiac arrhythmias were not associated with worse racing outcomes: therefore, their role in poor performance remains unclear.
Collapse
Affiliation(s)
- Chiara Maria Lo Feudo
- Equine Sports Medicine Laboratory “Franco Tradati”, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy; (C.M.L.F.)
| | - Luca Stucchi
- Equine Sports Medicine Laboratory “Franco Tradati”, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy; (C.M.L.F.)
| | - Giovanni Stancari
- Veterinary Teaching Hospital, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy
| | - Bianca Conturba
- Veterinary Teaching Hospital, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy
| | - Chiara Bozzola
- Equine Sports Medicine Laboratory “Franco Tradati”, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy; (C.M.L.F.)
| | - Enrica Zucca
- Equine Sports Medicine Laboratory “Franco Tradati”, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy; (C.M.L.F.)
| | - Francesco Ferrucci
- Equine Sports Medicine Laboratory “Franco Tradati”, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900 Lodi, Italy; (C.M.L.F.)
| |
Collapse
|
2
|
Tilley P, Simões J, Sales Luis JP. Effects of a 15° Variation in Poll Flexion during Riding on the Respiratory Systems and Behaviour of High-Level Dressage and Show-Jumping Horses. Animals (Basel) 2023; 13:ani13101714. [PMID: 37238147 DOI: 10.3390/ani13101714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 04/29/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023] Open
Abstract
From previous studies, the International Society for Equitation Science has advised that further research be conducted on the physiological/psychological effects of less-exacerbated poll flexion angles. We aimed to evaluate the effects of two riding poll flexion positions with a difference of only 15° on the respiratory systems and behaviour of horses through an evaluation of dynamic airway collapse via over-ground endoscopy, the pharyngeal diameter, pleural pressure, arterial oxygenation and lactate, HR/RR, and the occurrence of conflict behaviours. Twenty high-level dressage and twenty show-jumping horses underwent a 40 min ridden test at a ground angle of 85°; 3 weeks later, they underwent a ridden test at a 100° ground angle (the angle between the ground and the line from the forehead to the muzzle) and in a cross-over design. Using a mixed model for repeated measures, Wilcoxon/Friedman tests were carried out according to the experimental design and/or error normality. For both groups, at 100°, conflict behaviours and upper airway tract abnormalities were significantly more frequent, and the pleural pressure was higher, and the pharyngeal diameter was lower. At 85°, relaxation behaviours were significantly more frequent. Lactate was significantly higher at 100° only in the dressage horses. Compared to the first test at 85°, the HR/RR were significantly lower at the beginning of the second test (at 100°) but higher at the end. The significant differences identified in these dressage and show-jumping horses support the idea that an increase of just 15° in riding poll flexion can have negative effects on the respiratory system and behaviour of a horse and therefore on its welfare.
Collapse
Affiliation(s)
- Paula Tilley
- Centre for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, Av. Universidade Técnica, 1300-477 Lisbon, Portugal
- Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Lisbon, Portugal
| | - Joana Simões
- Centre for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, Av. Universidade Técnica, 1300-477 Lisbon, Portugal
- Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Lisbon, Portugal
- Equine Clinical Academic Department, Faculty of Veterinary Medicine, Lusófona University, 1749-024 Lisbon, Portugal
| | - José Paulo Sales Luis
- Centre for Interdisciplinary Research in Animal Health (CIISA), Faculty of Veterinary Medicine, University of Lisbon, Av. Universidade Técnica, 1300-477 Lisbon, Portugal
- Associate Laboratory for Animal and Veterinary Sciences (AL4AnimalS), 5000-801 Lisbon, Portugal
| |
Collapse
|
3
|
Ellis KL, Contino EK, Nout‐Lomas YS. Poor performance in the horse: Diagnosing the non‐orthopaedic causes. EQUINE VET EDUC 2022. [DOI: 10.1111/eve.13712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Katherine L. Ellis
- Gail Holmes Equine Orthopedic Research Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences Colorado State University Fort Collins Colorado USA
| | - Erin K. Contino
- Gail Holmes Equine Orthopedic Research Center, Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences Colorado State University Fort Collins Colorado USA
| | - Yvette S. Nout‐Lomas
- Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences Colorado State University Fort Collins Colorado USA
| |
Collapse
|
4
|
Mazan M. Equine exercise physiology-challenges to the respiratory system. Anim Front 2022; 12:15-24. [PMID: 35711503 PMCID: PMC9197307 DOI: 10.1093/af/vfac035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Melissa Mazan
- Clinical Sciences, Tufts University Cummings School of Veterinary Medicine, 200 Westborough Road, North Grafton, MA 01536, USA
| |
Collapse
|
5
|
Lo Feudo CM, Stucchi L, Cavicchioli P, Stancari G, Conturba B, Zucca E, Ferrucci F. Association between dynamic upper airway obstructions and fitness parameters in Standardbred racehorses during high-speed treadmill exercise. J Am Vet Med Assoc 2022; 260:1343-1350. [DOI: 10.2460/javma.22.02.0072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
OBJECTIVE
To evaluate the association between the severity of dynamic upper airway obstruction (DUAO) and selected fitness parameters in Standardbred racehorses measured by treadmill test.
ANIMALS
191 Standardbred racehorses that underwent a standardized diagnostic protocol for poor performance evaluation between 2002 and 2021 at the Veterinary Teaching Hospital, University of Milan.
PROCEDURES
Horses underwent a diagnostic protocol including clinical examination, lameness evaluation, laboratory analyses, ECG, resting upper airway endoscopy, metabolic incremental treadmill test, high-speed treadmill endoscopy, postexercise tracheobronchoscopy, and bronchoalveolar lavage fluid cytology. On the basis of findings of the high-speed treadmill endoscopy, horses were divided into the following groups: no DUAO, mild DUAO (medial deviation of the aryepiglottic folds or epiglottic entrapment), severe DUAO (dorsal displacement of the soft palate, nasopharyngeal collapse, dynamic laryngeal collapse, or epiglottic retroversion), and multiple DUAOs (different forms of DUAO occurring concomitantly). Fitness parameters, measured by incremental treadmill test, included speed at a heart rate of 200 bpm (V200), speed and heart rate at a lactate concentration of 4 mmol/L (VLa4, HRLa4), peak lactate, maximum speed, maximum hematocrit, and minimum pH. Data were compared between groups by use of descriptive and statistical analyses.
RESULTS
Horses affected by severe or multiple DUAOs showed lower V200 and VLa4, compared to the no-DUAO group; horses with multiple DUAOs also had higher peak lactate concentrations compared to horses without DUAOs.
CLINICAL RELEVANCE
While mild forms of DUAO do not affect athletic capacity, severe forms of DUAO and multiple DUAOs may lead to reduced fitness in Standardbred racehorses by impairing aerobic capacity.
Collapse
Affiliation(s)
- Chiara M. Lo Feudo
- Equine Sports Medicine Laboratory “Franco Tradati,” Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Luca Stucchi
- Veterinary Teaching Hospital, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Pietra Cavicchioli
- Equine Sports Medicine Laboratory “Franco Tradati,” Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Giovanni Stancari
- Veterinary Teaching Hospital, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Bianca Conturba
- Veterinary Teaching Hospital, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Enrica Zucca
- Equine Sports Medicine Laboratory “Franco Tradati,” Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| | - Francesco Ferrucci
- Equine Sports Medicine Laboratory “Franco Tradati,” Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, Lodi, Italy
| |
Collapse
|
6
|
Fitzharris LE, Franklin SH, McConnell AK, Hezzell MJ, Allen KJ. Inspiratory muscle training for the treatment of dynamic upper airway collapse in racehorses: A preliminary investigation. Vet J 2021; 275:105708. [PMID: 34147643 DOI: 10.1016/j.tvjl.2021.105708] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 05/01/2021] [Accepted: 06/14/2021] [Indexed: 12/13/2022]
Abstract
Exercise-induced upper airway collapse (UAC) probably occurs when the stabilising muscles of the upper airway are unable to withstand the dramatic changes in airflow and pressure that occurs during exercise. In racehorses, the mainstay of treatment is surgical intervention. In human athletes, exercise-induced laryngeal obstruction has been treated successfully with inspiratory muscle training (IMT). The aims of this study were: (1) to assess the feasibility of IMT in racehorses; and (2) describe the exercising endoscopy findings pre- and post-IMT in racehorses diagnosed with dynamic UAC. Horses undergoing IMT wore a mask with an attached threshold-valve to apply an additional load during inspiration, creating a training stimulus with the purpose of increasing upper airway muscle strength. Each horse underwent IMT once daily, while standing in the stable, 5-6 days/week for 10 weeks. Endoscopy recordings were analysed in a blinded manner using an objective grading scheme and subjective pairwise analysis. Seventeen horses successfully completed the IMT protocol, with full information available for 10 horses. Objective grading analysis showed a lower grade of vocal fold collapse (6/9 horses), palatal instability (7/10 horses) and intermittent dorsal displacement of the soft palate (5/7 horses) post-IMT. Pairwise subjective analysis suggested better overall airway function post-IMT in 3/10 horses. The main limitations of this preliminary investigation were the low number of horses examined and lack of a control population. Further research is required to investigate the effects of IMT on upper airway muscle strength and to evaluate its efficacy for prevention and treatment of UAC.
Collapse
Affiliation(s)
- L E Fitzharris
- Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU, UK.
| | - S H Franklin
- University of Adelaide, School of Animal and Veterinary Sciences, Roseworthy Campus, Mudla Wirra Rd, Roseworthy, SA 5371, Australia
| | | | - M J Hezzell
- Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU, UK
| | - K J Allen
- Bristol Veterinary School, University of Bristol, Langford, Bristol, BS40 5DU, UK
| |
Collapse
|
7
|
Vermedal H, O'Leary JM, Fjordbakk CT, McAloon CG, Løkslett H, Stadsnes B, Fretheim-Kelly ZL, Strand E. Outcome analysis of 95 harness racehorses with confirmed dorsal displacement of the soft palate treated with laryngeal tie-forward surgery. Equine Vet J 2021; 54:693-702. [PMID: 34101884 DOI: 10.1111/evj.13479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 04/27/2021] [Accepted: 05/20/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND The laryngeal tie-forward (LTF) procedure is commonly used to treat intermittent dorsal displacement of the soft palate (iDDSP). There is a wide range in reported efficacy of treating horses with and without a definitive diagnosis of iDDSP. OBJECTIVES To evaluate the racing performance of harness racehorses in which iDDSP had been definitely diagnosed and treated solely with the LTF procedure. STUDY DESIGN Retrospective case series. METHODS Ninety-five harness racehorses were treated with LTF for confirmed iDDSP. A definite diagnosis of iDDSP was made with high-speed treadmill or overground endoscopy. Upper respiratory tract (URT) disorders, short-term complications, and horses returning for recurrence of URT problems were recorded. Performance before and after LTF was assessed by reviewing career race records and comparing performance index (PI), and racing speed marks from the baseline, preoperative, and postoperative periods. The effect of basihyoid-cricoid (BC) net distance shortened on racing performance was assessed. RESULTS Postoperatively, PI increased in 36/54 (67%, 95% CI 54%-79%) of experienced racehorses, and 44/67 (66%, 54%-77%) established or improved their racing speed mark relative to the preoperative period. As a group, PI decreased by a mean (SE) of 0.9 (0.17) points (P < .001) prior to diagnosis/surgery. Postoperatively, PI increased by 0.5 (0.16) points (P = .003), and racing speed improved by 0.83 (0.22) s (P < .001). Twenty-five percent (17%-34%) and 49% (39%-60%) of horses did not demonstrate a decline in PI and racing speed prior to diagnosis, respectively. Net BC distance shortening did not affect performance postoperatively. Twenty of 95 horses (21%, 13%-29%) had confirmed recurrence of iDDSP 46-708 days postoperatively. MAIN LIMITATIONS Not all horses were evaluated with exercising endoscopy postoperatively. Racehorses inevitably develop other racing-related problems which confound studies of this nature. CONCLUSIONS This study provides scientific support for the use of LTF to treat iDDSP in harness racehorses although iDDSP seems to affect harness racehorses differently as individuals.
Collapse
Affiliation(s)
- Hanna Vermedal
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
- School of Veterinary Medicine, Equine Clinical Studies, University College Dublin, Dublin, Ireland
| | - John Mark O'Leary
- School of Veterinary Medicine, Equine Clinical Studies, University College Dublin, Dublin, Ireland
| | - Cathrine T Fjordbakk
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
| | - Conor G McAloon
- School of Veterinary Medicine, Herd Health and Animal Husbandry, University College Dublin, Dublin, Ireland
| | - Hege Løkslett
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
| | - Birgitte Stadsnes
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
| | - Zoe L Fretheim-Kelly
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
| | - Eric Strand
- Faculty of Veterinary Medicine, Companion Animal Clinical Science, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
8
|
Joó K, Duque Betancourt D, Vasquez Marin T, Parra Moyano LA. Evaluation of Overground Endoscopy Findings in Colombian Criollo Paso Horses. J Equine Vet Sci 2021; 99:103374. [PMID: 33781434 DOI: 10.1016/j.jevs.2021.103374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/21/2020] [Accepted: 12/28/2020] [Indexed: 11/26/2022]
Abstract
The dynamic upper airway functional (URT) problems of Colombian paso horses (CPH) have not been investigated in literature up to date. These horses perform special walking gaits with high poll flexion of the neck. Our goal is to evaluate the upper airway mechanics in CPH, showing abnormal respiratory sounds and poor performance during exercise. Resting and overground endoscopy was performed in 40 CPHs. Statistical analyses were performed using the sciPy package. One-tailed Fisher exact tests were used to check for positive contingency between each pair of upper respiratory tract disorder (P < .05). Arytenoid cartilage collapse was observed in 35 of 40 cases during exercise. Among these, dynamic laryngeal collapse (DLC) was the most significant finding, but ventromedial luxation of the apex of the corniculate process of the arytenoid and recurrent laryngeal neuropathy was also observed. Dorsal displacement of the soft palate was only detected in 4 of 40 cases. DLC was significantly associated with vocal cord collapse, nasopharyngeal collapse, and medial collapse of the margins of the epiglottis, and medial collapse of the margins of the epiglottis was associated with nasopharyngeal collapse. DLC is only a typical feature in some special breeds worldwide. We suggest that the extensive poll flexion and the relatively small laryngeal lumen and high intensitivity workload are the most important predisposing factors of DLC. Ventromedial luxation of the apex of the corniculate process of the arytenoid was over-represented in our caseload, compared with other studies. Whereas, despite the intensive workload, dorsal displacement of the soft palate was relatively uncommon. We presume that this could also be tailored to the high poll flexion performed during the special gaits.
Collapse
Affiliation(s)
- Kinga Joó
- Szent István University, Kaposvár Campus, Doctoral School in Animal Science, Kaposvár, Hungary.
| | | | | | | |
Collapse
|
9
|
Fretheim-Kelly Z, Fjordbakk CT, Fintl C, Krontveit R, Strand E. A bitless bridle does not limit or prevent dynamic laryngeal collapse. Equine Vet J 2020; 53:44-50. [PMID: 32449540 DOI: 10.1111/evj.13287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/17/2020] [Accepted: 05/09/2020] [Indexed: 11/28/2022]
Abstract
BACKGROUND Bits have often been incriminated as a cause of upper respiratory tract obstruction in horses; however, no scientific studies are available to confirm or refute these allegations. Clinical signs of dynamic laryngeal collapse associated with poll flexion (DLC) are induced when susceptible horses are ridden or driven into the bit. OBJECTIVE To determine whether use of Dr Cook's™ Bitless Bridle, instead of a conventional snaffle bit bridle, would reduce the severity of DLC in affected horses measured objectively using inspiratory tracheal pressures. STUDY DESIGN Intervention study using each horse as its own control in a block randomised order. METHODS Nine Norwegian Swedish Coldblooded trotters previously diagnosed with DLC were exercised on two consecutive days using a standardised high-speed treadmill protocol with either a conventional bridle with a snaffle bit, or Dr Cook's™ Bitless Bridle. Head and neck position, rein tension, inspiratory tracheal pressure measurements, and laryngeal videoendoscopy recordings were obtained. A heart rate greater than 200 bpm, and similar degrees of poll flexion/head height, had to be achieved in both bridles for the individual horse's data to be included for comparison. RESULTS Seven horses' data met the inclusion criteria. The change in mean inspiratory tracheal pressure between free and flexion phases in the bitless bridle (-15.2 ± 12.3 cmH2 O) was significantly greater (P < .001) than in the snaffle bit bridle (-9.8 ± 7.9 cmH2 O). Mean inspiratory pressure during the free phase was significantly (P < .001) more negative with the snaffle bit bridle (-32.3 ± 6.3 cmH2 O), vs the bitless bridle (-28.5 ± 6.9 cmH2 O). Mean pressures in flexion phase, snaffle bridle (-42.1 ± 10.8 cmH2 O), vs bitless bridle (-43.7 ± 15.6 cmH2 O) where not significantly different between bridles (P = .2). MAIN LIMITATION Small sample size due to difficulty recruiting suitable clinical cases. CONCLUSIONS This study could not provide any clear evidence that the effect of a snaffle bit in a horse's mouth influences the development or severity of DLC. Instead, head and neck angles induced by rein tension seem to be the key event in provoking DLC in susceptible horses.
Collapse
Affiliation(s)
- Zoe Fretheim-Kelly
- Faculty of Veterinary Medicine, Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway.,Haukeland University Hospital, Bergen, Norway
| | - Cathrine T Fjordbakk
- Faculty of Veterinary Medicine, Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - Constanze Fintl
- Faculty of Veterinary Medicine, Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | | | - Eric Strand
- Faculty of Veterinary Medicine, Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
10
|
Vermedal H, Strand E. Dynamic laryngeal collapse associated with poll flexion as a complication of laryngeal tie‐forward surgery in three harness racehorses. Vet Surg 2020; 49:600-606. [DOI: 10.1111/vsu.13351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 08/30/2019] [Accepted: 09/21/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Hanna Vermedal
- Faculty of Veterinary MedicineNorwegian University of Life Sciences Oslo Norway
| | - Eric Strand
- Faculty of Veterinary MedicineNorwegian University of Life Sciences Oslo Norway
| |
Collapse
|
11
|
Kallmyr A, Giving EM, Moen LO, Øverlie M, Holm T, David F. Complete resection of the alar folds in eight standing horses with a bipolar dividing and vessel-sealing device. Vet Surg 2020; 49:521-528. [PMID: 32027042 PMCID: PMC7155021 DOI: 10.1111/vsu.13383] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/25/2019] [Accepted: 12/26/2019] [Indexed: 12/02/2022]
Abstract
Objective To describe a resection technique of the alar folds in the standing horse. Study design Retrospective case study. Animals Eight Standardbred racing trotters. Methods Horses in which alar fold collapse had been diagnosed between 2017 and 2018 were included in this study. All horses underwent alar fold resection under standing sedation and regional anesthesia with a bipolar electrosurgical open sealer/divider device (LigaSure). Intraoperative and postoperative complications were recorded. A Wilcoxon signed‐rank test was used to compare differences in median prize money earning pre‐surgery and post‐surgery (P < .05). Results The surgical procedure was short (20‐30 min), with minimal (1/8) to no (7/8) bleeding and was well tolerated in all cases. Complete resection of the alar folds along with 3 to 5 cm of the ventral conchal cartilage was achieved. No complications were observed post‐surgery with satisfactory second intention healing, allowing return to training/racing within 3 to 6 weeks post‐surgery in all cases. Median earnings post‐surgery increased (P = .03) compared with pre‐surgery. Conclusion Alar fold resection with bipolar electrosurgical energy offered a good alternative to the traditional surgical approaches performed under general anesthesia. The surgery significantly improved race earnings and performance while avoiding the risk associated with general anesthesia and offered a short and complication‐free rehabilitation period. Clinical impact This study describes a surgical technique offering a novel approach to resection of the alar folds in the standing horse.
Collapse
Affiliation(s)
| | | | | | | | - Therese Holm
- Evidensia Lørenskog Dyreklinikk, Lørenskog, Norway
| | - Florent David
- Equine Veterinary Medical Center, a member of Qatar Foundation, Doha, Qatar.,College of Health & Life Science, Hamad Bin Khalifa University, Doha, Qatar
| |
Collapse
|
12
|
Fretheim-Kelly ZL, Halvorsen T, Clemm H, Roksund O, Heimdal JH, Vollsæter M, Fintl C, Strand E. Exercise Induced Laryngeal Obstruction in Humans and Equines. A Comparative Review. Front Physiol 2019; 10:1333. [PMID: 31736771 PMCID: PMC6831747 DOI: 10.3389/fphys.2019.01333] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 10/07/2019] [Indexed: 12/03/2022] Open
Abstract
Dynamic obstructions of the larynx are a set of disorders that occur during exercise in equines and humans. There are a number of similarities in presentation, diagnosis, pathophysiology and treatment. Both equines and humans present with exercise intolerance secondary to dyspnea. During laryngoscopy at rest, the larynx appears to function normally. Abnormalities are only revealed during laryngoscopy at exercise, seemingly triggered by increased ventilatory demands, and quickly resolve after cessation of exercise. Lower airway disease (asthma being the most prevalent condition), cardiac disease and lack of fitness are the major differentials in both species. Laryngoscopic examination during exercise should be performed from rest to peak exertion to allow for a comprehensive diagnosis, including where the airway collapse begins, and thereafter how it progresses. Dynamic disorders with most visual similarity between humans and equines are: aryepiglottic fold collapse (both species); equine dynamic laryngeal collapse (DLC) relative to some forms of human combined supraglottic/glottic collapse; and epiglottic retroversion (both species). Quantitative grading techniques, such as airway pressure measurement, that have proven effective in veterinary research are currently being piloted in human studies. Conditions that appear visually similar are treated in comparable ways. The similarities of anatomy and certain types of dynamic collapse would suggest that the equine larynx provides a good model for human upper respiratory tract obstruction during exercise. Thus, close collaboration between veterinarians and medical personal may lead to further advancements in understanding pathophysiologic processes, and enhance the development of improved diagnostic tests and treatments that will benefit both species.
Collapse
Affiliation(s)
- Zoe Louise Fretheim-Kelly
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway.,Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway
| | - Thomas Halvorsen
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway.,Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Hege Clemm
- Department of Pediatrics, Haukeland University Hospital, Bergen, Norway
| | - Ola Roksund
- Department of Pediatrics, Haukeland University Hospital, Bergen, Norway.,Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Bergen, Norway
| | - John-Helge Heimdal
- Department of Clinical Science, Faculty of Medicine, University of Bergen, Bergen, Norway.,Department of Oral Surgery, Haukeland University Hospital, Bergen, Norway
| | - Maria Vollsæter
- Department of Pediatrics, Haukeland University Hospital, Bergen, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Constanze Fintl
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Eric Strand
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
13
|
Velie BD, Smith PM, Fjordbakk CT, Solé M, Jäderkvist Fegraeus K, Rosengren MK, Røed KH, Ihler CF, Lindgren G, Strand E. Exploring the genetics underpinning dynamic laryngeal collapse associated with poll flexion in Norwegian-Swedish Coldblooded Trotter racehorses. Equine Vet J 2019; 52:174-180. [PMID: 31461557 DOI: 10.1111/evj.13171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 08/15/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Dynamic laryngeal collapse (DLC) associated with poll flexion is the most common disorder of the upper respiratory tract (URT) in the Norwegian-Swedish Coldblooded Trotter (NSCT). The disorder, which has also been diagnosed in other breeds of trotters and gaited horses, appears to be related to anatomic phenotypes and only occurs during poll flexion when the horse is exercised 'on the bit'. OBJECTIVES Identify genomic regions associated with DLC in the NSCT by combining a rigorous phenotyping protocol with genomic data from a high-density equine genotyping array. STUDY DESIGN Prospective case/control study. METHODS High-speed treadmill endoscopy was used to phenotype horses (n = 61) for DLC, distinguishing between cases and controls. Genome-wide association (GWA) analysis of DLC status was then performed using a principal component approach (PCA) with haplotype analyses subsequently performed for regions containing single-nucleotide polymorphisms (SNPs) above the suggestive genome-wide significance (GWS) threshold (P<1.0 × 10-5 ). RESULTS One region containing 10 SNPs (Equus caballus chromosome [ECA] 7: 89,601,935-94,647,192) was above the suggestive GWS threshold. Two inferred haplotypes in this region demonstrated significant differences (P<0.001) between cases and controls, with the most frequent haplotype resulting in a significantly increased risk of DLC. MAIN LIMITATIONS Small sample size as a result of stringent phenotyping protocols. CONCLUSIONS The current study highlights a candidate genomic region on ECA7 as potentially important with regard to the manifestation of DLC. Further exploration of this region and the genes included within it will bring veterinarians and researchers closer to fully understanding the biological mechanisms underlying DLC in horses.
Collapse
Affiliation(s)
- B D Velie
- Faculty of Science, School of Life and Environmental Sciences, University of Sydney, Sydney, Australia.,Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - P M Smith
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - C T Fjordbakk
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - M Solé
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - K Jäderkvist Fegraeus
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - M K Rosengren
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - K H Røed
- Department of Basic Sciences and Aquatic Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - C F Ihler
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| | - G Lindgren
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Livestock Genetics, Department of Biosystems, KU Leuven, Leuven, Belgium
| | - E Strand
- Department of Companion Animal Clinical Sciences, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
14
|
Strand E, Össurardóttir S, Wettre KB, Fjordbakk CT. Alar fold resection in 25 horses: Clinical findings and effect on racing performance and airway mechanics (1998-2013). Vet Surg 2019; 48:835-844. [PMID: 31002392 DOI: 10.1111/vsu.13214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 03/11/2019] [Accepted: 04/01/2019] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To report clinical findings and performance in horses in which alar fold collapse (AFC) had been diagnosed and surgically treated and to assess form and degree of respiratory obstruction. STUDY DESIGN Retrospective case series. ANIMALS Twenty-one standardbreds, 2 coldblooded trotter racehorses, 1 thoroughbred, and 1 Icelandic horse. METHODS Alar fold collapse was diagnosed on the basis of continuous abnormal expiratory flutter noise coinciding with filling of the false nostrils during exercise on a high-speed treadmill that was alleviated by suturing the alar folds (AF) temporarily in a dorsal position. In 5 cases, nasopharyngeal airway pressures were assessed. Performance after complete, bilateral AF resection was assessed by reviewing career race records and by owner or trainer telephone interviews. RESULTS Horses presented because of poor performance, abnormal respiratory noise, or both. Additional dynamic disorders were identified in 12 of 21 standardbreds (intermittent dorsal displacement of the soft palate: n = 10; collapse of the roof of the nasopharynx: n = 2). Expiratory nasopharyngeal pressures seemed elevated in horses with AFC (range, +10.8 to +21.8 cm H2 O) compared with normal reference values. Dorsal fixation as well as complete surgical resection of the AF improved expiratory nasopharyngeal pressures to reported normal levels. At a mean of 68 months (range, 7-121) follow-up, 20 of 25 horses had competed after surgery, and 13 of 17 of the harness racehorses had established or improved their kilometer racing time marks. CONCLUSION Alar fold collapse caused mild to moderate expiratory obstruction and may have contributed to secondary nasopharyngeal collapse in this population. CLINICAL SIGNIFICANCE Complete surgical resection seems effective for treating AFC. Nasopharyngeal pressure measurement is a potential tool for confirming the diagnosis of AFC.
Collapse
Affiliation(s)
- Eric Strand
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Saga Össurardóttir
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Kjersti B Wettre
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| | - Cathrine T Fjordbakk
- Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Oslo, Norway
| |
Collapse
|
15
|
Hackett ES, Leise BS. Exercising upper respiratory videoendoscopic findings of 50 competition draught horses with abnormal respiratory noise and/or poor performance. Equine Vet J 2018; 51:370-374. [DOI: 10.1111/evj.13026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 09/21/2018] [Indexed: 12/01/2022]
Affiliation(s)
- E. S. Hackett
- Department of Clinical Sciences Colorado State University Fort Collins Colorado USA
| | - B. S. Leise
- Department of Veterinary Clinical Sciences Louisiana State University Baton Rouge Louisiana USA
| |
Collapse
|
16
|
Velie BD, Jäderkvist Fegraeus K, Ihler CF, Lindgren G, Strand E. Competition lifespan survival analysis in the Norwegian‐Swedish Coldblooded Trotter racehorse. Equine Vet J 2018; 51:206-211. [DOI: 10.1111/evj.12989] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 07/02/2018] [Indexed: 11/29/2022]
Affiliation(s)
- B. D. Velie
- Department of Animal Breeding and Genetics Swedish University of Agricultural Sciences Uppsala Sweden
| | - K. Jäderkvist Fegraeus
- Department of Animal Breeding and Genetics Swedish University of Agricultural Sciences Uppsala Sweden
| | - C. F. Ihler
- Department of Companion Animal Clinical Sciences Faculty of Veterinary Medicine Norwegian University of Life Sciences Oslo Norway
| | - G. Lindgren
- Department of Animal Breeding and Genetics Swedish University of Agricultural Sciences Uppsala Sweden
| | - E. Strand
- Department of Companion Animal Clinical Sciences Faculty of Veterinary Medicine Norwegian University of Life Sciences Oslo Norway
| |
Collapse
|
17
|
Equine Welfare during Exercise: An Evaluation of Breathing, Breathlessness and Bridles. Animals (Basel) 2017; 7:ani7060041. [PMID: 28587125 PMCID: PMC5483604 DOI: 10.3390/ani7060041] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/22/2017] [Accepted: 05/23/2017] [Indexed: 01/05/2023] Open
Abstract
Simple Summary Horses have superior athletic capabilities due largely to their exceptional cardiorespiratory responses during exercise. This has particular relevance to horses’ potential to experience breathlessness, especially when their athletic performance is reduced by impaired respiratory function. Breathlessness, incorporating three types of unpleasant experiences, has been noted as of significant animal welfare concern in other mammals. However, the potential for breathlessness to occur in horses as usually ridden wearing bitted bridles has not yet been evaluated in detail. Accordingly, key physiological responses to exercise and the consequences of impaired respiratory function are outlined. Then the physiological control of breathing and the generation of the aversive experiences of breathlessness are explained. Finally, the potential for horses with unimpaired and impaired respiratory function to experience the different types of breathlessness is evaluated. This information provides a basis for considering the circumstances in which breathlessness may have significant negative welfare impacts on horses as currently ridden wearing bitted bridles. Potential beneficial impacts on respiratory function of using bitless bridles are then discussed with emphasis on the underlying mechanisms and their relevance to breathlessness. It is noted that direct comparisons of cardiorespiratory responses to exercise in horses wearing bitless and bitted bridles are not available and it is recommended that such studies be undertaken. Abstract Horses engaged in strenuous exercise display physiological responses that approach the upper functional limits of key organ systems, in particular their cardiorespiratory systems. Maximum athletic performance is therefore vulnerable to factors that diminish these functional capacities, and such impairment might also lead to horses experiencing unpleasant respiratory sensations, i.e., breathlessness. The aim of this review is to use existing literature on equine cardiorespiratory physiology and athletic performance to evaluate the potential for various types of breathlessness to occur in exercising horses. In addition, we investigate the influence of management factors such as rein and bit use and of respiratory pathology on the likelihood and intensity of equine breathlessness occurring during exercise. In ridden horses, rein use that reduces the jowl angle, sometimes markedly, and conditions that partially obstruct the nasopharynx and/or larynx, impair airflow in the upper respiratory tract and lead to increased flow resistance. The associated upper airway pressure changes, transmitted to the lower airways, may have pathophysiological sequelae in the alveolae, which, in their turn, may increase airflow resistance in the lower airways and impede respiratory gas exchange. Other sequelae include decreases in respiratory minute volume and worsening of the hypoxaemia, hypercapnia and acidaemia commonly observed in healthy horses during strenuous exercise. These and other factors are implicated in the potential for ridden horses to experience three forms of breathlessness—”unpleasant respiratory effort”, “air hunger” and “chest tightness”—which arise when there is a mismatch between a heightened ventilatory drive and the adequacy of the respiratory response. It is not known to what extent, if at all, such mismatches would occur in strenuously exercising horses unhampered by low jowl angles or by pathophysiological changes at any level of the respiratory tract. However, different combinations of the three types of breathlessness seem much more likely to occur when pathophysiological conditions significantly reduce maximal athletic performance. Finally, most horses exhibit clear behavioural evidence of aversion to a bit in their mouths, varying from the bit being a mild irritant to very painful. This in itself is a significant animal welfare issue that should be addressed. A further major point is the potential for bits to disrupt the maintenance of negative pressure in the oropharynx, which apparently acts to prevent the soft palate from rising and obstructing the nasopharynx. The untoward respiratory outcomes and poor athletic performance due to this and other obstructions are well established, and suggest the potential for affected animals to experience significant intensities of breathlessness. Bitless bridle use may reduce or eliminate such effects. However, direct comparisons of the cardiorespiratory dynamics and the extent of any respiratory pathophysiology in horses wearing bitted and bitless bridles have not been conducted. Such studies would be helpful in confirming, or otherwise, the claimed potential benefits of bitless bridle use.
Collapse
|
18
|
General Systemic States. Vet Med (Auckl) 2017. [PMCID: PMC7195945 DOI: 10.1016/b978-0-7020-5246-0.00004-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
19
|
|
20
|
Franklin SH, Allen KJ. Assessment of dynamic upper respiratory tract function in the equine athlete. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12432] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S. H. Franklin
- School of Animal and Veterinary Sciences; University of Adelaide; Roseworthy Australia
| | - K. J. Allen
- Equine Sports Medicine Centre; University of Bristol; UK
| |
Collapse
|
21
|
Allen KJ, van Erck-Westergren E, Franklin SH. Exercise testing in the equine athlete. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12410] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- K. J. Allen
- Equine Sports Medicine Centre; University of Bristol; Langford UK
| | | | - S. H. Franklin
- School of Animal and Veterinary Sciences; University of Adelaide; Roseworthy South Australia Australia
| |
Collapse
|
22
|
|
23
|
Fjordbakk CT, Revold T, Goodwin D, Piercy RJ. Histopathological assessment of intrinsic laryngeal musculature in horses with dynamic laryngeal collapse. Equine Vet J 2014; 47:603-8. [PMID: 25256848 DOI: 10.1111/evj.12357] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 09/03/2014] [Indexed: 12/01/2022]
Abstract
REASONS FOR PERFORMING STUDY The pathogenesis of bilateral dynamic laryngeal collapse associated with poll flexion (DLC) of horses is unknown but might be associated with intrinsic laryngeal muscle weakness. OBJECTIVES To investigate histopathological characteristics of the cricoarytenoideus dorsalis, the cricothyroid (CT) and the cricoarytenoideus lateralis muscles in DLC-affected horses and compare these with unaffected controls. Our hypotheses were that evidence of neurogenic atrophy of the CT or cricoarytenoideus dorsalis muscles would be found in DLC-affected horses and that observed changes would be symmetrically (left/right) distributed, or that muscle fibre diameter would be significantly reduced in DLC-affected horses compared to unaffected controls, reflecting an underlying paresis. STUDY DESIGN Case-control study. METHODS Five DLC horses and 8 controls were included. Muscle samples were harvested immediately following euthanasia. Fibre type proportions and size were evaluated by multiple immunofluorescence labelling of cryosections, and compared between sides (left/right) and groups (DLC-affected cases/ unaffected controls). Subjective and objective assessments of fibre type grouping were compared between sides and groups. RESULTS Fibre type proportions, fibre size and the subjective assessment of fibre type grouping did not reveal any statistically significant differences between the groups. Objective assessment of fibre type grouping revealed significantly more large clusters of T1 fibres within the left cricoarytenoideus lateralis muscle of DLC-affected cases versus controls, and within the right CT muscle of control horses compared to the DLC-cases. CONCLUSIONS The absence of bilateral symmetric fibre type grouping, fibre type loss and fibre atrophy in the DLC-affected cases do not support a neuromuscular component within the pathogenesis of DLC. The objective assessment of fibre type grouping revealed some statistical differences between the DLC-affected cases and the unaffected controls; however, these findings were inconsistent with regard to DLC. An alternative aetiology of DLC seems likely.
Collapse
Affiliation(s)
- C T Fjordbakk
- Department of Companion Animal Clinical Sciences, Equine Teaching Hospital, Norwegian School of Veterinary Science, Oslo, Norway
| | - T Revold
- Department of Companion Animal Clinical Sciences, Equine Teaching Hospital, Norwegian School of Veterinary Science, Oslo, Norway
| | - D Goodwin
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Sciences and Services, Royal Veterinary College, London, UK
| | - R J Piercy
- Comparative Neuromuscular Diseases Laboratory, Department of Clinical Sciences and Services, Royal Veterinary College, London, UK
| |
Collapse
|
24
|
Fjordbakk CT, Chalmers HJ, Holcombe SJ, Strand E. Results of upper airway radiography and ultrasonography predict dynamic laryngeal collapse in affected horses. Equine Vet J 2013; 45:705-10. [PMID: 23662675 DOI: 10.1111/evj.12066] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 01/27/2013] [Indexed: 11/27/2022]
Abstract
REASONS FOR PERFORMING STUDY The pathogenesis of dynamic bilateral laryngeal collapse (DLC) associated with poll flexion is unknown. Diagnosis is dependent upon exercise endoscopy while replicating the flexed head position harness racehorses experience during racing. OBJECTIVES To describe the effects of poll flexion on rostrocaudal laryngeal positioning and laryngeal lumen width in resting horses diagnosed with DLC compared to controls, and to establish diagnostic criteria for DLC by use of diagnostic imaging. STUDY DESIGN Case-control study. METHODS Fifty harness racehorses were prospectively included in the study: 25 cases diagnosed with DLC by treadmill endoscopy and 25 controls in which treadmill endoscopy revealed no abnormal findings. Laryngeal radiography and ultrasonography were obtained in neutral and flexed head positions. Laryngeal positioning and laryngohyoid conformation were compared between the groups and head positions. RESULTS Poll flexion induced a greater rostral advancement of the larynx in relation to the hyoid apparatus in resting harness racehorses affected with DLC compared to controls (P = 0.007). At the level of the vocal folds, poll flexion resulted in a smaller laryngeal lumen width in horses affected with DLC compared to controls (P = 0.04). Horses were significantly more likely to be affected with DLC when the thyrohyoid bone to thyroid cartilage distance was ≥12 mm in poll flexion (odds ratio 21.3, 95% confidence interval 3.65-124.8, P = 0.004) and when laryngeal lumen width at the level of the vocal folds was less in poll flexion than in the neutral head position (odds ratio 8.4; 95% confidence interval 1.6-44.1, P = 0.012). CONCLUSIONS AND POTENTIAL RELEVANCE In DLC horses, poll flexion advanced the larynx more rostrally and resulted in a decreased airway lumen width compared to control horses. Laryngeal ultrasound and radiography may facilitate the diagnosis of DLC at rest.
Collapse
Affiliation(s)
- C T Fjordbakk
- Department of Companion Animal Clinical Sciences, Equine Teaching Hospital, Norwegian School of Veterinary Science, Norway
| | | | | | | |
Collapse
|
25
|
Kelly PG, Reardon RJM, Johnston MS, Pollock PJ. Comparison of dynamic and resting endoscopy of the upper portion of the respiratory tract in 57 Thoroughbred yearlings. Equine Vet J 2013; 45:700-4. [DOI: 10.1111/evj.12061] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 01/27/2013] [Indexed: 11/30/2022]
Affiliation(s)
- P. G. Kelly
- Weipers Centre for Equine Welfare; School of Veterinary Medicine; University of Glasgow; UK
| | - R. J. M. Reardon
- Weipers Centre for Equine Welfare; School of Veterinary Medicine; University of Glasgow; UK
| | | | - P. J. Pollock
- Weipers Centre for Equine Welfare; School of Veterinary Medicine; University of Glasgow; UK
| |
Collapse
|
26
|
Barakzai SZ, Cheetham J. Endoscopic examination of exercising horses: Effects on diagnosis and treatment of upper respiratory tract disorders. Equine Vet J 2012; 44:501-3. [DOI: 10.1111/j.2042-3306.2012.00625.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
27
|
Strand E, Skjerve E. Complex dynamic upper airway collapse: associations between abnormalities in 99 harness racehorses with one or more dynamic disorders. Equine Vet J 2011; 44:524-8. [PMID: 22168356 DOI: 10.1111/j.2042-3306.2011.00516.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
REASONS FOR PERFORMING STUDY Many horses demonstrate dynamic collapse of more than one upper respiratory tract (URT) structure during high-speed treadmill videoendoscopy (HSTV). OBJECTIVES To report the frequency of complex dynamic URT collapse in harness racehorses and determine if an association exists between occurrence of certain disorders. METHODS Retrospective study of 99 Standardbreds and Coldblooded trotters that had one or more dynamic URT disorders identified during HSTV between 1998 and 2006. The horses underwent HSTV using a protocol that included periods of free head carriage and poll flexion until fully fatigued. Dynamic abnormalities were classified as: dynamic laryngeal collapse (DLC) associated with poll flexion; axial deviation of the aryepiglottic folds (ADAF); dynamically flaccid epiglottis (FE); caudal palatal instability (PI); intermittent dorsal displacement of the soft palate (iDDSP); pharyngeal collapse (PC); alar fold collapse (AFC) and nasal flutter (NF). Cluster analysis and Fisher's exact test was performed between groups. Significance was set at P<0.05. RESULTS The overall incidence of complex dynamic URT collapse was 69.7%. Axial deviation of the aryepiglottic folds was significantly associated with PI (P<0.0001) and FE (P<0.0001); iDDSP was significantly associated with PI (P = 0.004) only. Dynamic laryngeal collapse associated with poll flexion was significantly associated with FE (P = 0.002). Cluster analysis confirmed strong associations between the above diagnosis groups and weaker associations between others. CONCLUSION Caudal PI seems to result in 2 diagnosis groupings: one that leads to ADAF and the other to iDDSP. Dynamic collapse of the margins of the epiglottis was a common finding in this study strongly associated with DLC, PI and ADAF. POTENTIAL CLINICAL RELEVANCE The associations between certain dynamic diagnoses identified in this study seems best explained as due to local anatomic and functional weaknesses that influence other structures through the Bernouilli principle, rather than being due to a generalised neurological disorder.
Collapse
Affiliation(s)
- E Strand
- Equine Section, Norwegian School of Veterinary Science, Oslo, Norway.
| | | |
Collapse
|