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Ahern BJ, de Klerk K, Hogg LR, Vallance SA, Bertin FR, Franklin SH. Evaluation of postsale endoscopy as a predictor of future racing performance in an Australian thoroughbred yearling population. Aust Vet J 2022; 100:254-260. [PMID: 35191021 PMCID: PMC9305470 DOI: 10.1111/avj.13155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 01/23/2022] [Accepted: 02/04/2022] [Indexed: 12/02/2022]
Abstract
Introduction Upper airway endoscopy of thoroughbred (TB) yearlings is commonly used in an attempt to predict laryngeal function (LF) and its impact on future race performance. The aim of this study was to determine if different grading systems and laryngeal grades were correlated with future performance. Materials and Methods Postsale endoscopic recordings were obtained from an Australian TB yearling sale during a four‐year period from 2008 to 2011. Horses were included if they had a diagnostic postsale video endoscopic recording and raced within Australia. Recordings were graded using the Havemeyer system and subsequently recategorised according to the Lane scale and two condensed scales. Performance data were sourced from Racing Australia and comparisons were made between groups. Results A total of 1244 horses met the inclusion criteria. There were no significant differences in sex or sales price between groups. There were no significant differences in the number of starts or wins between groups for any grading system. For the condensed Havemeyer scale, horses with intermediate LF were separated into two groups. Significant differences in earnings were found between ‘normal’ and ‘abnormal’ (P = 0.02) and ‘intermediate‐low’ and ‘abnormal’ grades (P = 0.03). There were no significant differences between horses with ‘intermediate‐high’ and ‘abnormal’ grades (P = 0.40). No significant differences were found between the two intermediate grades (P = 0.60) or between horses with normal LF and either ‘intermediate‐low’ or ‘intermediate‐high’ grades (P = 0.99). Discussion Resting LF in Australian yearling TBs assessed using a condensed Havemeyer grading scale had some predictive value for future racing performance. This information should be considered when performing yearling endoscopic examinations.
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Affiliation(s)
- B J Ahern
- The University of Queensland, School of Veterinary Science, Equine Specialist Hospital, Gatton, Queensland, 4343
| | - K de Klerk
- Hawkesbury Equine Veterinary Centre, 226 Hawkesbury Valley Way, Clarendon, New South Wales, 2756, Australia
| | - L R Hogg
- Kangaroo Island Veterinary Clinic, 252 Playford Highway, Kingscote, Kangaroo Island, South Australia, 5223, Australia
| | - S A Vallance
- Advantage Equine, Ascot Vale, Victoria, 3032, Australia
| | - F R Bertin
- The University of Queensland, School of Veterinary Science, Equine Specialist Hospital, Gatton, Queensland, 4343
| | - S H Franklin
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy Campus, Roseworthy, South Australia, 5371, Australia
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Miller SM. Endoscopic recurrent laryngeal neuropathy grade prevalence in a sample of thoroughbred yearlings at public auction in South Africa (2013-2019). J S Afr Vet Assoc 2020; 91:e1-e5. [PMID: 32370531 PMCID: PMC7203182 DOI: 10.4102/jsava.v91i0.2013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Revised: 02/13/2020] [Accepted: 02/19/2020] [Indexed: 11/29/2022] Open
Abstract
Endoscopy of thoroughbred (TB) yearlings at public auctions is common in South Africa. Laryngeal function (LF) is a common concern of buyers of young TBs. Cancellation of sale because of LF abnormalities is a concern for both the vendor and the buyer, with recurrent laryngeal neuropathy (RLN) being a common cause of sale cancellation. The aim of this descriptive study was to determine the prevalence of RLN at South African premier TB yearling sales. This study was designed as a retrospective descriptive analysis of upper respiratory tract (URT) endoscopic examinations to determine RLN grade, performed at two premier TB yearling sales in South Africa. Results of buyer-requested endoscopic examination from 2013 to 2019 were included. Results from the yearling sales were analysed for prevalence of RLN grade (using Rakestraw’s 4-point system) and compared to similar previously published studies. For analysis of effects of gender on RLN grading, horses were grouped and Fisher’s exact test was used to determine if there was a relationship between gender and grade. For comparison of the effects of age on grade, and sales year on grade, a Kruskal–Wallis test was conducted. A value of p < 0.05 was considered significant. A total of 858 horses were examined out of 4149 offered for sale; there were 57.58% colts and 42.42% fillies (mean age of 18.1 months). The annual percentage for grade 1 was 84.04% ± 9.98%, for grade 2: 14.49% ± 10.69%, for grade 3: 0.71% ± 0.57% and for grade 4: 0.76% ± 0.94%. There were no other significant findings. The exclusive nature of the sale and the increasing proclivity for pre-sale scoping may have skewed the results. This study shows that RLN grade incidences in TB yearlings at public auctions in South Africa are as follows: grade 1: 84.04%, grade 2: 14.49%, grade 3: 0.71% and grade 4: 0.76%. The results were similar to that of an adult population of horses examined in South Africa in a previous study.
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McLellan J, Plevin S. Evaluation of videoendoscopic examinations of arytenoid function in the 2‐year‐old Thoroughbred: Can we all agree? Equine Vet J 2018; 51:364-369. [DOI: 10.1111/evj.13030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 09/24/2018] [Indexed: 12/12/2022]
Affiliation(s)
- J. McLellan
- Florida Equine Veterinary Associates Ocala Florida USA
| | - S. Plevin
- Florida Equine Veterinary Associates Ocala Florida USA
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4
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McGivney CL, Sweeney J, Gough KF, Hill EW, Katz LM. Serial evaluation of resting and exercising overground endoscopic examination results in young Thoroughbreds with no treatment intervention. Equine Vet J 2018; 51:192-197. [DOI: 10.1111/evj.12994] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 07/09/2018] [Indexed: 11/30/2022]
Affiliation(s)
- C. L. McGivney
- UCD School of Agriculture and Food Science University College Dublin Belfield, Dublin Ireland
| | - J. Sweeney
- UCD School of Business University College Dublin Belfield, Dublin Ireland
| | - K. F. Gough
- UCD School of Agriculture and Food Science University College Dublin Belfield, Dublin Ireland
| | - E. W. Hill
- UCD School of Agriculture and Food Science University College Dublin Belfield, Dublin Ireland
| | - L. M. Katz
- UCD, School of Veterinary Medicine University College Dublin Belfield, Dublin Ireland
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5
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McGivney CL, Sweeney J, David F, O'Leary JM, Hill EW, Katz LM. Intra- and interobserver reliability estimates for identification and grading of upper respiratory tract abnormalities recorded in horses at rest and during overground endoscopy. Equine Vet J 2016; 49:433-437. [DOI: 10.1111/evj.12653] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 11/06/2016] [Indexed: 10/20/2022]
Affiliation(s)
- C. L. McGivney
- School of Agriculture and Food Science; University College Dublin; Belfield, Dublin Ireland
| | - J. Sweeney
- School of Business; University College Dublin; Belfield, Dublin Ireland
| | - F. David
- Bjerke Dyrehospital En Rikstotoklinikk; Økern Torgv; Oslo Norway
| | - J. M. O'Leary
- School of Veterinary Medicine; University College Dublin; Belfield, Dublin Ireland
| | - E. W. Hill
- School of Agriculture and Food Science; University College Dublin; Belfield, Dublin Ireland
| | - L. M. Katz
- School of Veterinary Medicine; University College Dublin; Belfield, Dublin Ireland
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O'Neill HD, Ballegeer EA, De Feijter-Rupp HL, Stick JA, Derksen FJ, Robinson NE. Ultrasound-guided biopsy of the cricoarytenoideus lateralis muscle: technique and safety in horses. Equine Vet J 2013; 46:244-8. [PMID: 23679063 DOI: 10.1111/evj.12105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
REASONS FOR PERFORMING STUDY Current diagnosis of recurrent laryngeal neuropathy (RLN) depends upon disease recognition in the clinically affected horse. Biopsy of the intrinsic laryngeal muscles may provide a method to identify the changes in fibre-type composition that occur in RLN before clinical signs become apparent. OBJECTIVE To develop an ultrasound-guided biopsy technique of the left cricoarytenoideus lateralis muscle (CALM) and evaluate its efficacy and safety in vivo. STUDY DESIGN A longitudinal descriptive study. METHODS Six standing horses underwent ultrasound-guided biopsy of the left CALM. Frozen muscle cores were obtained with a breast biopsy tool. Serial endoscopic, ultrasonographic and physical examinations before and for 8 weeks after the biopsy were assessed for iatrogenic trauma. Histologies of representative muscle core cross-sections were analysed for the total number of muscle fibres obtained with each biopsy. RESULTS There were no immediate complications of the procedure and the left CALM was harvested in all instances. Biopsy samples had an average weight of 0.043 g (range = 0.023-0.077 g) and contained 3418 fibres in cross-section (range = 711-7143). Laryngeal endoscopic grade did not change significantly between prebiopsy and the end of the 8 week follow-up. The left CALM had significantly greater echogenicity than the right throughout the study (P<0.001), but there was no difference between the prebiopsy CALM echogenicity and that at completion of the study. CONCLUSIONS Ultrasound-guided biopsy of the left CALM is safe and well tolerated, providing a minimally invasive method to obtain muscle from healthy horses. This new technique may be applicable in research and clinical settings.
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Affiliation(s)
- H D O'Neill
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, USA
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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
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8
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Compostella F, Tremaine WH, Franklin SH. Retrospective study investigating causes of abnormal respiratory noise in horses following prosthetic laryngoplasty. Equine Vet J 2012:27-30. [DOI: 10.1111/j.2042-3306.2012.00612.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Results of a haplotype-based GWAS for recurrent laryngeal neuropathy in the horse. Mamm Genome 2011; 22:613-20. [DOI: 10.1007/s00335-011-9337-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 05/16/2011] [Indexed: 11/30/2022]
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10
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Variability of resting endoscopic grading for assessment of recurrent laryngeal neuropathy in horses. Equine Vet J 2010; 41:342-6. [DOI: 10.2746/042516409x423073] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Lane JG, Bladon B, Little DRM, Naylor JRJ, Franklin SH. Dynamic obstructions of the equine upper respiratory tract. Part 2: Comparison of endoscopic findings at rest and during high-speed treadmill exercise of 600 Thoroughbred racehorses. Equine Vet J 2010; 38:401-7. [PMID: 16986599 DOI: 10.2746/042516406778400619] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY The reliability of diagnoses of obstructive conditions of the upper respiratory tract (URT) based on examinations performed at rest vs. at exercise is controversial. OBJECTIVE To compare diagnosis of URT by endoscopy at rest with that achieved during high-speed treadmill exercise (HSTE). HYPOTHESIS Endoscopy of URT at rest, when performed in isolation from other simpler techniques is unreliable in the prediction of dynamic respiratory obstructions. METHODS Endoscopic findings of 600 Thoroughbred racehorses during quiet breathing were compared with findings during high-speed treadmill exercise. Other parameters were also assessed for their specificity in diagnosis. RESULTS Endoscopy of the resting horse showed low sensitivity (0.15) in the diagnosis of dorsal displacement of the soft palate (DDSP) and palatal instability (PI). When endoscopy and reported noises were taken together there was still a 35% misdiagnosis rate. Although there was significant association between resting laryngeal function score (LFS) and dynamic vocal cord and/or arytenoid cartilage collapse at exercise, 19% of horses with a grade 4/5 LFS were able to attain and maintain full abduction during exercise and 7% of those with 'normal' grades 1 or 2 LFS at rest showed dynamic laryngeal collapse when exerted. Sensitivity of the diagnostic model was greatly increased (80%) when a history of inspiratory noise and palpable intrinsic muscle atrophy were included. CONCLUSIONS AND POTENTIAL RELEVANCE Endoscopy of the upper respiratory tract of static horses is unreliable in the diagnosis of dynamic obstructions of the URT and should not be used in isolation in surgical decision-making or in the assessment of horses at the time of sale.
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Affiliation(s)
- J G Lane
- Department of Clinical Veterinary Science, University of Bristol, Langford, UK
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Brown JA, Hinchcliff KW, Jackson MA, Dredge AF, O'Callaghan RA, McCaffrey JR, Slocombe RF, Clarke AF. Prevalence of pharyngeal and laryngeal abnormalities in Thoroughbreds racing in Australia, and their association with performance. Equine Vet J 2010; 37:397-401. [PMID: 16163940 DOI: 10.2746/042516405774480021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY Little information is available regarding the prevalence of abnormalities of the upper airway and their association with performance in the general population of Thoroughbred racehorses. OBJECTIVES To describe the prevalence of selected abnormalities of the upper airway and their association with performance in Thoroughbred racehorses in Australia. HYPOTHESIS That abnormalities of the upper airway of Thoroughbred racehorses are associated with poor race performance. METHODS Rhinolaryngoscopy was performed after racing and presence and characteristics of abnormalities of the larynx and pharynx were recorded in a prospective cross-sectional study of Thoroughbred horses racing in Victoria, Australia. RESULTS Rhinolaryngoscopy was performed once on each of 744 horses over 35 months. Fifty abnormalities of the upper airway were detected in 47 horses (6.3%, 95% confidence interval [CI] 4.7-83%). Epiglottic entrapment was detected in 7 horses (0.9%, 95% CI 0.4-1.9%) and was significantly (P = 0.015) associated with superior performance. Grade 2 asymmetry (4 grade scale) of the left arytenoid cartilage was detected in 9 horses (1.2%, 95% CI 0.5-2.4%) and was also associated with superior performance (P<0.001). Ulceration or erosion of the mucosa of the axial surface of one or both arytenoids was detected in 18 horses (2.4%, 95% CI 13-3.8%) and was not associated with alterations in exercise performance (P = 0.31). CONCLUSIONS Epiglottic entrapment, Grade 2 laryngeal asymmetry and mucosal erosions detected in Thoroughbred racehorses were not associated with impaired performance; therefore, surgical correction and concern over laryngeal function in horses with Grade 2 asymmetry may not be necessary in individuals performing to expectation.
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Affiliation(s)
- J A Brown
- School of Veterinary Science, University of Melbourne, Princes Highway, Werribee, Victoria 3030, Australia
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Saulez MN, Gummow B. Prevalence of pharyngeal, laryngeal and tracheal disorders in thoroughbred racehorses, and effect on performance. Vet Rec 2009; 165:431-5. [DOI: 10.1136/vr.165.15.431] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- M. N. Saulez
- Section of Equine Medicine, Department of Companion Animal Clinical Studies
| | - B. Gummow
- Section of Epidemiology; Faculty of Veterinary Science; University of Pretoria; Onderstepoort 0110 South Africa
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Dixon PM, Hahn CN, Barakzai SZ. Recurrent laryngeal neuropathy (RLN) research: where are we and to where are we heading? Equine Vet J 2009; 41:324-7. [PMID: 19562891 DOI: 10.2746/042516409x423082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- P M Dixon
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Midlothian, Scotland, UK
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Davidson EJ, Martin BB, Parente EJ. Use of successive dynamic videoendoscopic evaluations to identify progression of recurrent laryngeal neuropathy in three horses. J Am Vet Med Assoc 2007; 230:555-8. [PMID: 17302556 DOI: 10.2460/javma.230.4.555] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
CASE DESCRIPTION 3 racehorses were evaluated because of poor performance or abnormal noise originating from the upper portion of the respiratory tract. CLINICAL FINDINGS During maximal exercise, initial dynamic videoendoscopy of the upper respiratory tract revealed complete arytenoid cartilage abduction in 2 horses and incomplete but adequate abduction of the left arytenoid cartilage in 1 horse. Subsequent exercising endoscopic evaluation revealed severe dynamic collapse of the left arytenoid cartilage and vocal fold in all 3 horses. TREATMENT AND OUTCOME 2 horses were treated with prosthetic left laryngoplasty and raced successfully. One horse was retired from racing. CLINICAL RELEVANCE Idiopathic laryngeal hemiplegia can be a progressive disease. Successive dynamic videoendoscopic upper airway evaluations were used to confirm progression of left laryngeal hemiplegia in these 3 horses. Videoendoscopy of the upper respiratory tract during exercise should be considered as part of the clinical evaluation of horses with signs of upper respiratory tract dysfunction.
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Affiliation(s)
- Elizabeth J Davidson
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348-1692, USA
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Adreani CM, Li ZB, Lehar M, Southwood LL, Habecker PL, Flint PW, Parente EJ. Myosin heavy chain composition in normal and atrophic equine laryngeal muscle. Vet Pathol 2007; 43:881-9. [PMID: 17099144 DOI: 10.1354/vp.43-6-881] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The myosin heavy chain (MHC) composition of a given muscle determines the contractile properties and, therefore, the fiber type distribution of the muscle. MHC isoform expression in the laryngeal muscle is modulated by neural input and function, and it represents the cellular level changes that occur with denervation and reinnervation of skeletal muscle. The objective of this study was to evaluate the pattern of MHC isoform expression in laryngeal muscle harvested from normal cadavers and cadavers with naturally occurring left laryngeal hemiplegia secondary to recurrent laryngeal neuropathy. Left and right thyroarytenoideus (TA) and cricoarytenoideus dorsalis (CAD) were obtained from 7 horses affected with left-sided intrinsic laryngeal muscle atrophy and from 2 normal horses. Frozen sections were evaluated histologically for degree of atrophy and fiber type composition. MHC isoform expression was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of muscle protein. Histologic atrophy was seen in all atrophic muscles and some right-sided muscles of 3 affected horses, as well as the left TA of 1 normal horse. Fiber type grouping or loss of type I muscle fibers was observed in the left-sided laryngeal muscles in all but 1 affected horse, as well as in the right muscles of 2 affected horses, and the left TA of 1 normal horse. SDS-PAGE showed 2 bands corresponding to the type I and type IIB myosin isoforms in the CAD and TA of the 2 normal horses. Affected horses demonstrated a trend toward increased expression of the type IIB isoform and decreased expression of the type I isoform in atrophic muscles. This study confirmed the presence of histologic abnormalities in grossly normal equine laryngeal muscle, and it demonstrated an increased expression of type IIB MHC with a concurrent decreased expression of type I MHC in affected muscles. Evaluation of muscle fiber changes at the cellular level under denervated and reinnervated conditions may aid in assessing future strategies for reinnervation or regeneration of atrophic laryngeal muscle.
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Affiliation(s)
- C M Adreani
- Department of Clinical Studies, New Bolton Center, 382 West Street Road, Kennett Square, PA 19348, USA.
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Taylor SE, Barakzai SZ, Dixon P. Ventriculocordectomy as the Sole Treatment for Recurrent Laryngeal Neuropathy: Long-Term Results from Ninety-Two Horses. Vet Surg 2006; 35:653-7. [PMID: 17026550 DOI: 10.1111/j.1532-950x.2006.00203.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To evaluate the effect ventriculocordectomy (VC) for treatment of recurrent laryngeal neuropathy (RLN) on exercise performance and owner satisfaction in a mixed-breed population of horses. STUDY DESIGN Retrospective study. ANIMALS Adult horses (n=92) with a history of abnormal respiratory noise and RLN. METHODS Retrospective analysis of horse that had unilateral VC (and contralateral ventriculectomy in 63 horses) for treatment of idiopathic RLN. Owners/trainers completed a questionnaire about complications and outcome at least 1 year after surgery. Performance index was determined using race records for previously raced Thoroughbreds to evaluate outcome. RESULTS Clinical signs included abnormal exercise-induced respiratory noises (noises; 52%), poor performance (11%), and noises and poor performance (37%). The median preoperative resting endoscopic grade of laryngeal function was Havemeyer grade III.1 (mild asymmetry). No discharge from the laryngotomy 1 week postoperatively occurred in 62% horses, 22% coughed after surgery, 66% made no noises, 9% continued to make noises at the canter, 21% made noise at the gallop, and 4% of owners were unsure whether noises were present. Ninety-three percent of horses returned to full work after surgery. Overall, 86% of owners considered the surgery worthwhile, 3% did not consider it worthwhile, and 11% were unsure. Surgery had a significantly beneficial effect on the racing performance index in Thoroughbreds (P=.004). CONCLUSIONS VC is a useful alternative to laryngoplasty for selected cases of RLN and is associated with a positive effect on exercise performance, a low postoperative complication rate, and a high rate of owner satisfaction. CLINICAL RELEVANCE Unilateral VC should be considered as a sole treatment in horses with low grades of RLN.
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Affiliation(s)
- Sarah E Taylor
- Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Scotland, UK.
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Schaaf KL, Kannegieter NJ, Lovell DK. Placement of a long term tracheal cannula in a Thoroughbred racehorse with bilateral laryngeal dysfunction. Aust Vet J 2006; 84:293-6. [PMID: 16911233 DOI: 10.1111/j.1751-0813.2006.00016.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A Thoroughbred horse with bilateral laryngeal dysfunction was treated by placement of a long term tracheal cannula in order to restore full athletic function. The horse initially presented with right-sided arytenoid dysfunction that was considered to be due to a congenital malformation of the laryngeal cartilage. This was corrected by a right-sided laryngoplasty and ventriculectomy. The horse re-presented 1 year later with idiopathic left laryngeal hemiplegia. The decision was made to place a long-term tracheal cannula due to the low success rate and high complication rate associated with other surgeries used to correct bilateral arytenoid dysfunction. A three-piece tracheotomy cannula and stopper were positioned under general anaesthesia. The horse rapidly adjusted to the tracheal cannula and no post-surgical complications were encountered. The horse resumed training 4 weeks postoperatively. Due to the rules governing racing in Australia the horse was exported to New Zealand where he continued his racing career. It was concluded that tracheotomy is a straightforward technique associated with minimal complications and can provide an excellent prognosis for return of full airway function in racing horses. It is recognised that many issues need to be considered prior to more general acceptance of this technique, including assessment of animal welfare issues and public perception. In appropriate cases consideration should be given to using long term placement of a tracheotomy cannula as a treatment option to restore maximal airflow in horses with upper airway obstruction.
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Affiliation(s)
- K L Schaaf
- Redlands Veterinary Clinic 433 Boundary Rd Thornlands, QLD. 4164
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Dixon PM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Pickles K, McCann J. Clinical and endoscopic evidence of progression in 152 cases of equine recurrent laryngeal neuropathy (RLN). Equine Vet J 2002; 34:29-34. [PMID: 11817549 DOI: 10.2746/042516402776181169] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Examination of the long-term histories and clinical findings was performed in 351 horses suffering from recurrent laryngeal neuropathy (RLN) to examine for possible evidence of progression of this disorder. Fifty-two out of 351 cases (15%) had evidence of progression of the degree of laryngeal dysfunction over a median period of 12 months (range 1.5-48 months) with the onset of progression occurring at median age 7 years. In 30 cases, there was both endoscopic (median deterioration of 3 endoscopic grades; range 1-5 grades) and clinical evidence, with 29 (97%) of these horses concurrently developing sudden-onset, abnormal exercise-related respiratory 'noises' and 13 (43%) concurrently reporting reduced exercise performance. In the remaining 22 horses there was solely clinical evidence of RLN progression, including the sudden onset of abnormal exercise-related respiratory sounds in 16 (73%) and the worsening of such sounds in 6 (23%), associated with reduced exercise performance in 13 (59%) of these 22 cases. Endoscopically, 13 (59%) of the latter 22 cases had marked (total or almost total) RLN that did not appear compatible with their previous exercise-performance histories. This evidence of progression of RLN may be of particular significance in disputes concerning horses that are apparently normal at pre-purchase examination but are later shown to have RLN and also in the surgical treatment of less severe cases of RLN.
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Affiliation(s)
- P M Dixon
- The Wellcome Trust Centre for Studies in Comparative Respiratory Medicine, The University of Edinburgh, Easter Bush Veterinary Centre, Midlothian, Scotland
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Dixon PM, McGorum BC, Railton DI, Hawe C, Tremaine WH, Pickles K, McCann J. Laryngeal paralysis: a study of 375 cases in a mixed-breed population of horses. Equine Vet J 2001; 33:452-8. [PMID: 11558739 DOI: 10.2746/042516401776254790] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Referred cases (n = 375) of laryngeal paralysis (1985-1998) from a mixed-breed equine population included 351 (94%) cases of recurrent laryngeal neuropathy (RLN) (idiopathic laryngeal hemiplegia) and 24 cases (6%) of laryngeal paralysis from causes other than RLN. Laryngeal movements were classified endoscopically into one of 6 grades, in contrast to the usual 4 grades. The RLN cases had a median grade 4 laryngeal paralysis, of which 96% were left-sided, 2% right-sided and 2% bilaterally affected. RLN cases included 204 (58%) Thoroughbred, 96 (27%) Thoroughbred-cross, 23 (7%) draught, 16 (5%) Warmbloods and 10 (3%) other breeds, including only 4 (1%) ponies. The median age of RLN cases at referral was 6 years (range 2-12) and their median height was 170.2 cm. The work of RLN horses included National Hunt racing (42%), flat racing (1%), hunting (19%), eventing (16%) and miscellaneous work (22%). Reported presenting signs in RLN-affected horses included abnormal exercise-related respiratory sounds in 90% and reduced exercise tolerance in only 64%. However, many horses were referred before their exercise tolerance could be fully assessed. Forty percent of the RLN cases had intercurrent disorders, including 10% with additional upper respiratory and 7% with lower respiratory tract diseases. The 24 nonidiopathic RLN cases included 12 with bilateral laryngeal paralysis, 11 (92%) of which were ponies. Bilateral laryngeal paralysis occurred with hepatic encephalopathy in 7 cases and following general anaesthesia in 2 cases. The 12 cases of acquired unilateral laryngeal paralysis included 7 caused by guttural pouch mycosis.
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Affiliation(s)
- P M Dixon
- The Wellcome Trust Centre for Studies in Comparative Respiratory Medicine, The University of Edinburgh, Easter Bush Veterinary Centre, Easter Bush, Midlothian, Scotland
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