1
|
Campos Schweitzer A, Mespoulhès-Rivière C, Möller D, Ducharme N, Genton M, Farfan M, Rossignol F. Laryngeal reinnervation using the spinal accessory nerve: Electromyographic study of the sternomandibularis muscle. Equine Vet J 2022; 55:515-523. [PMID: 35831933 DOI: 10.1111/evj.13859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 07/08/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Selective laryngeal reinnervation using the first and second cervical nerve (C1C2) is a treatment option for recurrent laryngeal neuropathy that aims to restore the function of the cricoarytenoideus dorsalis muscle (CAD). Despite the technique's satisfying success rate, it has several limitations. These triggered the search for another potential donor nerve that could reduce CAD muscle fatigue and shorten rehabilitation. The ventral branch of the spinal accessory nerve, providing motor innervation to the sternomandibularis (SM) muscle, was identified as a potentially well adapted nerve. OBJECTIVES To gather normative data from SM muscle activity induced by physiological spinal accessory nerve stimulation at rest and during exercise, and to determine SM muscle activity and fibre type recruitment relative to posture, gait, and respiratory cycle. STUDY DESIGN Clinical observational study. METHODS Surface electromyography of the SM muscle was performed in 9 horses: trained warmbloods, Thoroughbreds and Standardbreds. Signals were recorded in different feeding postures and at exercise, which included standardised treadmill exercise tests, lungeing and ridden work. RESULTS Timing of the SM muscle contraction coincided with inspiration at gallop. Intra-individual mean SM muscle activity increased with exercising speed (4 times higher in Thoroughbreds at gallop compared to walk and 7 times higher in Standardbreds at high-speed trot compared to walk). Moreover, the SM muscle was strongly activated at rest when the horse was grazing (7 times more compared to when it was eating out of a hay net or stable feeder). Frequency domain analysis revealed a predominant type I muscle fibre recruitment during feeding and at exercise (Type I muscle fibre activity was at least 2.5 times higher than type II muscle fibre activity). MAIN LIMITATIONS Lack of reference data on equine electromyography. CONCLUSIONS This study confirmed the potentially advantageous properties of the spinal accessory nerve for laryngeal reinnervation.
Collapse
Affiliation(s)
| | | | - Dirk Möller
- University of Applied Sciences, Osnabrück, Germany
| | - Norm Ducharme
- College of Veterinary Medicine, Cornell University, Ithaca, New York, USA
| | - Martin Genton
- Veterinary Clinic of Grosbois, Boissy-St-Léger, France
| | - Maëlle Farfan
- Veterinary Clinic of Grosbois, Boissy-St-Léger, France
| | | |
Collapse
|
2
|
Almonte H, Schumacher J, Johnson CR, Berk JT, Bell RP. Effect of a combination of butorphanol and detomidine on endoscopic assessment of laryngeal function in Thoroughbred yearlings. Vet Rec 2022; 190:e1483. [DOI: 10.1002/vetr.1483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 01/24/2022] [Accepted: 02/02/2022] [Indexed: 11/12/2022]
Affiliation(s)
| | - James Schumacher
- Department of Large Animal Clinical Sciences College of Veterinary Medicine University of Tennessee Knoxville Tennessee USA
| | | | | | | |
Collapse
|
3
|
Broyles AH, Embertson RM, Brett Woodie J, Machado V. The impact of grade of laryngeal function immediately prior to laryngoplasty and ipsilateral ventriculocordectomy on postoperative performance: 623 Thoroughbred racehorses (1998-2013). Equine Vet J 2021; 54:856-864. [PMID: 34626125 DOI: 10.1111/evj.13523] [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: 04/23/2020] [Accepted: 09/30/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND There is persistent concern among some trainers, owners and veterinarians regarding the effect of preoperative laryngeal function grade on the outcome of laryngoplasty and ventriculocordectomy (LPVC). OBJECTIVES To determine the effect of laryngeal function grade prior to LPVC on postoperative performance. STUDY DESIGN Retrospective case-series. METHODS Medical and race records of Thoroughbred racehorses diagnosed with recurrent laryngeal neuropathy (RLN) and treated with LPVC between 1998 and 2013 were reviewed. Horses were placed into three groups based on preoperative laryngeal function grade (grade III.1, grades III.2/III.3, and grade IV). The effect of preoperative laryngeal function grade on postoperative performance was determined by multivariable logistic regression, Cox proportional hazard model and multivariable linear regression analysis. RESULTS In a multivariable logistic regression, grade III.2/III.3 horses had 1.88 times higher odds (95% CI = 1.03-3.43) of racing after LPVC than grade IV (P = .04). A multivariable Cox's proportional hazard analysis controlling for race prior to surgery (P < .01) showed that likelihood of racing postoperatively was not different between grade III.1 and grade IV (P = .6), and although not statistically significant, there was a tendency for grades III.2/III.3 to be more likely to race postoperatively than horses with grade IV (P = .07). Kaplan-Meier survival analysis showed that grade IV horses took a longer time to race compared with grade III.1 and grade III.2/III.3. Laryngeal function grade did not influence the mean earnings per start. MAIN LIMITATIONS The small number of horses in the grade III.1 group compared with the III.2/III.3 and IV groups influenced the effect of grade III.1 on outcome. CONCLUSIONS Laryngeal function grade may affect likelihood of racing after LPVC, but not earnings per start. Grade III. 2/III.3 horses were more likely to race postoperatively than grade IV horses, and grade IV horses took a longer time to first race after LPVC.
Collapse
Affiliation(s)
- Ali H Broyles
- Rood and Riddle Equine Hospital, Lexington, Kentucky, USA
| | | | - J Brett Woodie
- Rood and Riddle Equine Hospital, Lexington, Kentucky, USA
| | - Vinicius Machado
- Department of Veterinary Sciences, Texas Tech University, Lubbock, Texas, USA
| |
Collapse
|
4
|
Abstract
Genetic factors influence the development of guttural pouch tympany, recurrent laryngeal neuropathy, severe equine asthma, exercise-induced pulmonary hemorrhage, and possibly also some malformations and infectious diseases of the respiratory tract. The current data suggest that most of these diseases are complex, resulting from the interaction between several genes and environmental factors. To date, no specific genes or causative mutations have been identified that would allow the development of practical genetic tests. In the future, genetic profiling panels, based on multiple genetic markers and environmental risk factors, may allow identification of individuals with an increased genetic risk.
Collapse
Affiliation(s)
- Vinzenz Gerber
- Department of Clinical Veterinary Medicine, Vetsuisse Faculty, Swiss Institute of Equine Medicine (ISME), University of Bern, and Agroscope, Laenggassstrasse 124, Berne 3012, Switzerland.
| |
Collapse
|
5
|
Barrett E, Arkins S. Abnormalities detected at pre-purchase examination of National Hunt racehorses presented at sale. Equine Vet J 2019; 52:281-289. [PMID: 31418917 DOI: 10.1111/evj.13164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 07/27/2019] [Indexed: 11/29/2022]
Abstract
BACKGROUND Few studies are available concerning prevalences of abnormalities in the Thoroughbred horse population. OBJECTIVES Determine the prevalence of commonly observed abnormalities in a National Hunt Thoroughbred population using results of pre-purchase examinations conducted at Thoroughbred sales venues. STUDY DESIGN Retrospective cross-sectional study. METHODS Veterinary pre-purchase examination certificates for 13,603 3- and 4-year-old Thoroughbred National Hunt horses from Tattersalls Ireland, Goffs Ireland and Doncaster Bloodstock Sales Ltd. (DBS) Sales were analysed. All conditions noted by the veterinarians were recorded to determine the prevalence of abnormalities. RESULTS Abnormalities were recorded in 73.6% of horses; 12.0% had abnormalities likely to prejudice their use for racing. Metacarpal/metatarsal exostoses and tarsal-plantar desmitis affected 17.1 and 19.4% of the sample respectively, while 9.9% were found to make abnormal respiratory noises and 5.3% had recurrent laryngeal neuropathy. Age, year of birth and sex significantly affected the prevalence of many abnormalities (P<0.001). The proportions of horses sold differed significantly between horses with and without some abnormalities, with unaffected horses significantly more likely to be sold (e.g., prejudicial findings present vs. non-prejudicial/none, 38.1% vs. 77.6% respectively, P<0.001). A range of abnormalities significantly negatively affected the price at sale (P<0.001). Significantly higher proportions of horses in the lower price categories had multiple abnormalities (P<0.001). MAIN LIMITATIONS The study consisted only of horses entered into store horse sales and presented for sale. Horses kept for racing or breeding purposes or horses withdrawn prior to the panel veterinary pre-purchase examination were not included. The upper respiratory tract was only examined endoscopically in horses found to have an abnormal respiratory noise. CONCLUSIONS A large proportion of 3- and 4-year-old Thoroughbred National Hunt horses intended for sale are affected by abnormalities. The prevalence of many abnormalities increases with age and certain abnormalities are viewed negatively by purchasers, affecting sale of the horse and achieved sale price.
Collapse
Affiliation(s)
- E Barrett
- Department of Biological Sciences, University of Limerick, Limerick, Ireland.,Oaklands Equine Hospital, Yarm, North Yorkshire, UK
| | - S Arkins
- Department of Biological Sciences, University of Limerick, Limerick, Ireland
| |
Collapse
|
6
|
Krueger CR, Lewis RD, McIlwraith CW, Major MD, Brakenhoff JE, Hand DR, Rowland AL, Hess AM, Johnson SW, Hackett ES. A retrospective cohort study of racing performance in Quarter Horses undergoing prosthetic laryngoplasty for treatment of recurrent laryngeal neuropathy. J Am Vet Med Assoc 2019; 254:496-500. [PMID: 30714865 DOI: 10.2460/javma.254.4.496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine effects of prosthetic laryngoplasty on return to racing, performance index, and career longevity in racing Quarter Horses with recurrent laryngeal neuropathy (RLN) and to evaluate performance variables for horses with RLN undergoing prosthetic laryngoplasty, compared with a control horse population. DESIGN Multicenter, retrospective cohort study. ANIMALS 162 racing Quarter Horses with RLN treated with prosthetic laryngoplasty (case horses) and 324 racing Quarter Horse without RLN (control horses). PROCEDURES Medical and race records of case and control horses examined at 5 referral centers between January 2000 and December 2015 were reviewed retrospectively. Two control horses were matched with each case horse. Return to racing, earnings, number of racing starts, performance index, and career longevity were evaluated. RESULTS The odds of returning to racing did not differ significantly between case and control horses but decreased with increasing age. Neither racing starts nor career longevity were affected by prosthetic laryngoplasty or by RLN grade. In fact, horses undergoing laryngoplasty for treatment of RLN and horses with the lowest RLN grade before surgery had higher performance indices after the surgery, compared with indices for control horses. CONCLUSIONS AND CLINICAL RELEVANCE The faster speeds and shorter distances raced with Quarter Horses could alter how RLN impacts respiratory variables and performance in Quarter Horses, compared with other racehorse breeds. Further study is needed to understand the impacts of RLN and surgical treatments for RLN in racing Quarter Horses.
Collapse
|
7
|
Brooks SA, Stick J, Braman A, Palermo K, Robinson NE, Ainsworth DM. Identification of loci affecting sexually dimorphic patterns for height and recurrent laryngeal neuropathy risk in American Belgian Draft Horses. Physiol Genomics 2018; 50:1051-1058. [DOI: 10.1152/physiolgenomics.00068.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Equine recurrent laryngeal neuropathy (RLN) is a bilateral mononeuropathy with an unknown etiology. In Thoroughbreds (TB), we previously demonstrated that the haplotype association for height (LCORL/NCAPG locus on ECA3, which affects body size) and RLN was coincident. In the present study, we performed a genome-wide association scan (GWAS) for RLN in 458 American Belgian Draft Horses, a breed fixed for the LCORL/NCAPG risk alelle. In this breed, RLN risk is associated with sexually dimorphic differences in height, and we identified a novel locus contributing to height in a sex-specific manner: MYPN (ECA1). Yet this specific locus contributes little to RLN risk, suggesting that other growth traits correlated to height may underlie the correlation to this disease. Controlling for height, we identified a locus on ECA15 contributing to RLN risk specifically in males. These results suggest that loci with sex-specific gene expression play an important role in altering growth traits impacting RLN etiology, but not necessarily adult height. These newly identified genes are promising targets for novel preventative and treatment strategies.
Collapse
Affiliation(s)
- Samantha A. Brooks
- Department of Animal Science, UF Genetics Institute, University of Florida, Gainesville, Florida
| | - John Stick
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan
| | - Ashley Braman
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan
| | - Katelyn Palermo
- Department of Animal Science, UF Genetics Institute, University of Florida, Gainesville, Florida
| | - N. Edward Robinson
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan
| | | |
Collapse
|
8
|
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
| |
Collapse
|
9
|
McGivney CL, Gough KF, McGivney BA, Farries G, Hill EW, Katz LM. Exploratory factor analysis of signalment and conformational measurements in Thoroughbred horses with and without recurrent laryngeal neuropathy. Equine Vet J 2018; 51:179-184. [DOI: 10.1111/evj.12984] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 06/18/2018] [Indexed: 11/30/2022]
Affiliation(s)
- C. L. McGivney
- UCD School of Agriculture and Food Science, University College Dublin Dublin Ireland
| | - K. F. Gough
- UCD School of Agriculture and Food Science, University College Dublin Dublin Ireland
| | - B. A. McGivney
- UCD School of Agriculture and Food Science, University College Dublin Dublin Ireland
| | - G. Farries
- UCD School of Agriculture and Food Science, University College Dublin Dublin Ireland
| | - E. W. Hill
- UCD School of Agriculture and Food Science, University College Dublin Dublin Ireland
| | - L. M. Katz
- UCD School of Veterinary Medicine University College Dublin Dublin Ireland
| |
Collapse
|
10
|
Draper ACE, Piercy RJ. Pathological classification of equine recurrent laryngeal neuropathy. J Vet Intern Med 2018; 32:1397-1409. [PMID: 29691904 PMCID: PMC6060325 DOI: 10.1111/jvim.15142] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 03/12/2018] [Accepted: 03/29/2018] [Indexed: 12/28/2022] Open
Abstract
Recurrent Laryngeal Neuropathy (RLN) is a highly prevalent and predominantly left-sided, degenerative disorder of the recurrent laryngeal nerves (RLn) of tall horses, that causes inspiratory stridor at exercise because of intrinsic laryngeal muscle paresis. The associated laryngeal dysfunction and exercise intolerance in athletic horses commonly leads to surgical intervention, retirement or euthanasia with associated financial and welfare implications. Despite speculation, there is a lack of consensus and conflicting evidence supporting the primary classification of RLN, as either a distal ("dying back") axonopathy or as a primary myelinopathy and as either a (bilateral) mononeuropathy or a polyneuropathy; this uncertainty hinders etiological and pathophysiological research. In this review, we discuss the neuropathological changes and electrophysiological deficits reported in the RLn of affected horses, and the evidence for correct classification of the disorder. In so doing, we summarize and reveal the limitations of much historical research on RLN and propose future directions that might best help identify the etiology and pathophysiology of this enigmatic disorder.
Collapse
Affiliation(s)
- Alexandra C. E. Draper
- Comparative Neuromuscular Disease LaboratoryDepartment is Clinical Science and Services, Royal Veterinary CollegeLondonUnited Kingdom
| | - Richard J. Piercy
- Comparative Neuromuscular Disease LaboratoryDepartment is Clinical Science and Services, Royal Veterinary CollegeLondonUnited Kingdom
| |
Collapse
|
11
|
Davison JA, Lumsden JM, Boston RC, Ahern BJ. Overground endoscopy in 311 Thoroughbred racehorses: findings and correlation to resting laryngeal function. Aust Vet J 2017; 95:338-342. [DOI: 10.1111/avj.12620] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/12/2016] [Accepted: 12/12/2016] [Indexed: 11/28/2022]
Affiliation(s)
- JA Davison
- Rossdales Equine Practice, Beaufort Cottage Stables; Newmarket Suffolk CB8 8JS UK
| | - JM Lumsden
- Randwick Equine Centre; Randwick New South Wales Australia
| | - RC Boston
- University of Pennsylvania, New Bolton Center; PA USA
| | - BJ Ahern
- University of Queensland; UQ Gatton Campus Gatton Queensland Australia
| |
Collapse
|
12
|
Karlheim B, Barton AK, Rohn K, Ohnesorge B. Validity of laryngeal ultrasonography in reference to endoscopy at rest and during exercise in Warmblood horses. EQUINE VET EDUC 2014. [DOI: 10.1111/eve.12285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- B. Karlheim
- Clinic for Horses; University of Veterinary Medicine Hannover; Germany
| | - A. K. Barton
- Clinic for Horses; University of Veterinary Medicine Hannover; Germany
- Equine Clinic; Free University of Berlin; Germany
| | - K. Rohn
- Institute for Epidemiology; University of Veterinary Medicine Hannover; Germany
| | - B. Ohnesorge
- Clinic for Horses; University of Veterinary Medicine Hannover; Germany
| |
Collapse
|
13
|
Gerber V, Tessier C, Marti E. Genetics of upper and lower airway diseases in the horse. Equine Vet J 2014; 47:390-7. [PMID: 24773614 DOI: 10.1111/evj.12289] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 04/12/2014] [Indexed: 11/30/2022]
Abstract
Genetic predispositions for guttural pouch tympany, recurrent laryngeal neuropathy and recurrent airway obstruction (RAO) are well documented. There is also evidence that exercise-induced pulmonary haemorrhage and infectious diseases of the respiratory tract in horses have a genetic component. The clinical expression of equine respiratory diseases with a genetic basis results from complex interactions between the environment and the genetic make-up of each individual horse. The genetic effects are likely to be due to variations in several genes, i.e. they are polygenic. It is therefore unlikely that single gene tests will be diagnostically useful in these disorders. Genetic profiling panels, combining several genetic factors with an assessment of environmental risk factors, may have greater value, but much work is still needed to uncover diagnostically useful genetic markers or even causative variants for equine respiratory diseases. Nonetheless, chromosomal regions associated with guttural pouch tympany, recurrent laryngeal neuropathy and RAO have been identified. The association of RAO with other hypersensitivities and with resistance to intestinal parasites requires further study. This review aims to provide an overview of the available data and current thoughts on the genetics of equine airway diseases.
Collapse
Affiliation(s)
- V Gerber
- Swiss Institute of Equine Medicine (ISME), DKV, Vetsuisse Faculty, University of Berne and ALP-Haras Avenches, Switzerland
| | - C Tessier
- ONIRIS, Ecole Nationale Vétérinaire, Agro-Alimentaire et de l'Alimentation Nantes-Atlantique, Equine Surgery, Nantes, France
| | - E Marti
- Division of Clinical Immunology, DCR-VPH, University of Berne, Switzerland
| |
Collapse
|
14
|
Boyko AR, Brooks SA, Behan-Braman A, Castelhano M, Corey E, Oliveira KC, Swinburne JE, Todhunter RJ, Zhang Z, Ainsworth DM, Robinson NE. Genomic analysis establishes correlation between growth and laryngeal neuropathy in Thoroughbreds. BMC Genomics 2014; 15:259. [PMID: 24707981 PMCID: PMC4051171 DOI: 10.1186/1471-2164-15-259] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 03/24/2014] [Indexed: 11/21/2022] Open
Abstract
Background Equine recurrent laryngeal neuropathy (RLN) is a bilateral mononeuropathy
with an unknown pathogenesis that significantly affects performance in
Thoroughbreds. A genetic contribution to the pathogenesis of RLN is
suggested by the higher prevalence of the condition in offspring of
RLN-affected than unaffected stallions. To better understand RLN
pathogenesis and its genetic basis, we performed a genome-wide association
(GWAS) of 282 RLN-affected and 268 control Thoroughbreds. Results We found a significant association of RLN with the
LCORL/NCAPG locus on ECA3 previously shown to affect
body size in horses. Using height at the withers of 505 of these horses, we
confirmed the strong association of this locus with body size, and
demonstrated a significant phenotypic and genetic correlation between height
and RLN grade in this cohort. Secondary genetic associations for RLN on
ECA18 and X did not correlate with withers height in our cohort, but did
contain candidate genes likely influencing muscle physiology and growth:
myostatin (MSTN) and integral membrane protein 2A
(ITM2A). Conclusions This linkage between body size and RLN suggests that selective breeding to
reduce RLN prevalence would likely reduce adult size in this population.
However, our results do not preclude the possibility of modifier loci that
attenuate RLN risk without reducing size or performance, or that the RLN
risk allele is distinct but tightly linked to the body size locus on ECA3.
This study is both the largest body size GWAS and the largest RLN GWAS
within Thoroughbred horses to date, and suggests that improved understanding
of the relationship between genetics, equine growth rate, and RLN prevalence
may significantly advance our understanding and management of this
disease.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Norman Edward Robinson
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI 48824, USA.
| |
Collapse
|
15
|
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.
Collapse
Affiliation(s)
- H D O'Neill
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, USA
| | | | | | | | | | | |
Collapse
|
16
|
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]
|
17
|
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]
|
18
|
DAVIDSON EJ, MARTIN BB, BOSTON RC, PARENTE EJ. Exercising upper respiratory videoendoscopic evaluation of 100 nonracing performance horses with abnormal respiratory noise and/or poor performance. Equine Vet J 2010; 43:3-8. [DOI: 10.1111/j.2042-3306.2010.00132.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
19
|
GARRETT KS, WOODIE JB, EMBERTSON RM. Association of treadmill upper airway endoscopic evaluation with results of ultrasonography and resting upper airway endoscopic evaluation. Equine Vet J 2010; 43:365-71. [DOI: 10.1111/j.2042-3306.2010.00216.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
20
|
Sedation with detomidine and acepromazine influences the endoscopic evaluation of laryngeal function in horses. Equine Vet J 2010; 39:553-6. [DOI: 10.2746/042516407x204177] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
21
|
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]
|
22
|
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.
Collapse
Affiliation(s)
- J G Lane
- Department of Clinical Veterinary Science, University of Bristol, Langford, UK
| | | | | | | | | |
Collapse
|
23
|
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
| |
Collapse
|
24
|
Rhee HS, Steel CM, Derksen FJ, Robinson NE, Hoh JFY. Immunohistochemical analysis of laryngeal muscles in normal horses and horses with subclinical recurrent laryngeal neuropathy. J Histochem Cytochem 2009; 57:787-800. [PMID: 19398607 PMCID: PMC2713078 DOI: 10.1369/jhc.2009.953844] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Accepted: 04/16/2009] [Indexed: 11/22/2022] Open
Abstract
We used immunohistochemistry to examine myosin heavy-chain (MyHC)-based fiber-type profiles of the right and left cricoarytenoideus dorsalis (CAD) and arytenoideus transversus (TrA) muscles of six horses without laryngoscopic evidence of recurrent laryngeal neuropathy (RLN). Results showed that CAD and TrA muscles have the same slow, 2a, and 2x fibers as equine limb muscles, but not the faster contracting fibers expressing extraocular and 2B MyHCs found in laryngeal muscles of small mammals. Muscles from three horses showed fiber-type grouping bilaterally in the TrA muscles, but only in the left CAD. Fiber-type grouping suggests that denervation and reinnervation of fibers had occurred, and that these horses had subclinical RLN. There was a virtual elimination of 2x fibers in these muscles, accompanied by a significant increase in the percentage of 2a and slow fibers, and hypertrophy of these fiber types. The results suggest that multiple pathophysiological mechanisms are at work in early RLN, including selective denervation and reinnervation of 2x muscle fibers, corruption of neural impulse traffic that regulates 2x and slow muscle fiber types, and compensatory hypertrophy of remaining fibers. We conclude that horses afflicted with mild RLN are able to remain subclinical by compensatory hypertrophy of surviving muscle fibers.
Collapse
Affiliation(s)
- Hannah S Rhee
- Discipline of Physiology, Bosch Institute, School of Medical Sciences, Faculty of Medicine, The University of Sydney, Australia
| | | | | | | | | |
Collapse
|
25
|
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
| | | | | |
Collapse
|
26
|
Robinson P, Williams KJ, Sullins KE, Arnoczky SP, Stick JA, Robinson NE, de Feijter-Rupp H, Derksen FJ. Histological evaluation of the equine larynx after unilateral laser-assisted ventriculocordectomy. Equine Vet J 2007; 39:222-5. [PMID: 17520972 DOI: 10.2746/042516407x175198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY Trans-endoscopic laser surgery, such as unilateral laser-assisted ventriculocordectomy (LVC), has gained popularity in the treatment of RLN because a laryngotomy incision or general anaesthesia are not required. However, removal of the vocal fold and ventricle takes considerable laser energy and could cause collateral tissue damage, including injury to the adjacent laryngeal cartilages. OBJECTIVES To document the histological effects of laser surgery on laryngeal tissues in horses that have undergone LVC for the treatment of laryngeal hemiplegia (LH). METHODS Six horses were used: 4 with experimentally induced LH that had subsequently undergone LVC 6 months prior to euthanasia; and, 2 horses were used as controls. One of the control horses with naturally occurring LH was used to study the effect of neuropathy alone, whereas the other was subjected to euthanasia immediately following LVC to evaluate the acute effect of laser surgery. Using a band saw, each larynx was sectioned transversely at 5 mm intervals and evaluated histologically. RESULTS Acutely, LVC caused thermal damage to adjacent soft tissues but did not affect the histology of the laryngeal cartilages. Six months after LVC, laryngeal cartilages were histologically normal and there was squamous metaplasia of the repaired laryngeal mucosa, resulting in restitution of the mucosal integrity. CONCLUSIONS Using a diode laser in contact fashion at 20 W, LVC can be used to remove the laryngeal vocal fold and ventricle without causing laryngeal cartilage damage. POTENTIAL RELEVANCE Laryngeal chondritis is an unlikely consequence of LVC.
Collapse
Affiliation(s)
- P Robinson
- Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, Michigan 48824, USA
| | | | | | | | | | | | | | | |
Collapse
|
27
|
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.
Collapse
Affiliation(s)
- C M Adreani
- Department of Clinical Studies, New Bolton Center, 382 West Street Road, Kennett Square, PA 19348, USA.
| | | | | | | | | | | | | |
Collapse
|
28
|
Lane JG, Bladon B, Little DRM, Naylor JRJ, Franklin SH. Dynamic obstructions of the equine upper respiratory tract. Part 1: observations during high-speed treadmill endoscopy of 600 Thoroughbred racehorses. Equine Vet J 2006; 38:393-9. [PMID: 16986598 DOI: 10.2746/042516406778400583] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY AND OBJECTIVE To review the prevalence of single and complex forms of dynamic airway obstructions within a large group of Thoroughbred horses in training referred for investigation of poor performance. METHODS Video-endoscopic recordings of the upper respiratory tract made during a standardised treadmill exercise test of 600 Thoroughbred racehorses were reviewed and analysed in real time and slow motion to identify dynamic collapse by the tissues bordering onto the pharyngeal and laryngeal airways. RESULTS Dynamic collapse within the nasopharynx or larynx was confirmed in 471 of the 600 horses. Dorsal displacement of the soft palate (DDSP; 50%) and palatal instability (33%) were the disorders most frequently identified. It was concluded that deglutition is not a significant event in the triggering of DDSP. Complex forms of dynamic collapse were present in 30% of the horses with upper respiratory tract obstructions. A significant influence of age on the prevalence of DDSP and dynamic laryngeal collapse was identified. There was an increased risk of DDSP in younger horses, and of laryngeal collapse in older horses. No association with gender or format of racing was identified. CONCLUSIONS AND POTENTIAL RELEVANCE Palatal instability and DDSP comprised the most frequently encountered forms of dynamic collapse within the upper respiratory tract of the Thoroughbred racehorses in this study and are probably expressions of the same nasopharyngeal malfunction. Complex obstructions, i.e. where more than one structure collapses into the airway, occur frequently and therefore treatments that address solitary disorders may often be unsuccessful. Younger horses were found to be at greater risk of sustaining DDSP while older horses seemed more at risk to vocal cord collapse but not to collapse of the arytenoid cartilage itself.
Collapse
Affiliation(s)
- J G Lane
- Department of Clinical Veterinary Science, University of Bristol, Langford, UK
| | | | | | | | | |
Collapse
|
29
|
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.
Collapse
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.
| | | | | |
Collapse
|
30
|
Dart AJ, Dowling BA, Smith CL. Upper airway dysfunction associated with collapse of the apex of the corniculate process of the left arytenoid cartilage during exercise in 15 horses. Vet Surg 2006; 34:543-7. [PMID: 16343139 DOI: 10.1111/j.1532-950x.2005.00085.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE To report dynamic collapse of the apex of the left corniculate process under the right corniculate process into the airway at the dorsal apposition of the paired arytenoid cartilages during exercise as a cause of upper airway dysfunction in horses. DESIGN Retrospective study. ANIMALS Fifteen horses with a history of poor performance and/or upper respiratory tract noise during exercise. METHODS Video recordings of all horses referred for upper airway evaluation using high-speed treadmill videoendoscopy (HSTV) between January 1998 and December 2003 were reviewed. Records of horses that developed dynamic collapse of the apex of the left corniculate process into the airway were included. Clinical history, age, gender, breed, and use of the horse were retrieved. RESULTS Of 309 horses referred for examination for poor performance and/or upper respiratory tract noise during exercise, 15 (4.9%) had collapse of the apex of the left corniculate process under the right and into the airway at the dorsal apposition between the paired arytenoid cartilages during HSTV. There were 3 females and 13 males, aged from 2 to 5 years. Five horses had previous surgery for left recurrent laryngeal neuropathy (RLN): 2 had nerve muscle pedicle graft and 3 had laryngeal prosthesis. During HSTV, all 15 horses had progressive collapse of the apex of the left corniculate process under the right at the dorsal apposition of the 2 arytenoid cartilages, and into the dorsal aspect of the rima glottidis. Review of video recordings revealed that collapse of the apex of the corniculate process was followed by progressive collapse of the left aryepiglottic fold and left vocal fold. The ventral aspect of the left corniculate cartilage maintained abduction in all horses. Two horses also had progressive collapse of the right vocal fold, 1 had rostral displacement of the palatopharyngeal arch, and another had dorsal displacement of the soft palate. CONCLUSIONS Dynamic collapse of the apex of the left corniculate process of the arytenoid cartilage under the right is an uncommon cause of upper airway dysfunction in horses and the pathogenesis is unclear. We speculate that the left arytenoideus transversus muscle is unable to support the dorsal apposition between the arytenoid cartilages. This loss of support allows the elastic cartilage of the left corniculate process to collapse under the right and into the airway, as inspiratory pressure increases during exercise. This condition may be associated with an unusually advanced neuropathy of the adductor components of the left recurrent laryngeal nerve and may be an unusual manifestation of RLN; however, this is speculative and further investigation is required to determine its cause. CLINICAL RELEVANCE Dynamic collapse of the apex of the left corniculate process and into the airway at the dorsal apposition between the paired arytenoid cartilages can only be diagnosed during HSTV. It is an uncommon cause of upper airway dysfunction but may affect the athletic potential of racing Thoroughbreds and Standardbreds.
Collapse
Affiliation(s)
- Andrew J Dart
- Faculty of Veterinary Science, The University of Sydney, New South Wales, Australia.
| | | | | |
Collapse
|
31
|
Curtis RA, Hahn CN, Evans DL, Williams T, Begg L. Thoracolaryngeal reflex latencies in Thoroughbred horses with recurrent laryngeal neuropathy. Vet J 2005; 170:67-76. [PMID: 15993790 DOI: 10.1016/j.tvjl.2004.03.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2004] [Indexed: 11/17/2022]
Abstract
Electrolaryngeography was used to study the latencies of the thoracolaryngeal adductor reflex in Thoroughbred horses with and without recurrent laryngeal neuropathy (RLN). Latencies were compared in horses with grades 1 and 2 RLN, diagnosed by endoscopy in resting horses. The reliability of the measurements, effect of sedation and correlations of latencies with age of the horse were also studied. There was no effect of sedation on reflex latency periods. The latency of the reflex period measured to a convolved peak of the electromyographic response was significantly different in horses with grades 1 and 2 disease; medians and quartile ranges were 0.067 (0.065-0.073) and 0.072 (0.068-0.074) s, respectively (P<0.05). Significant associations were found between reflex latencies and both horse age and the grade of RLN. Reflex latency measurements are reliable and sensitive, and may assist with the clinical appraisal of Thoroughbred horses with RLN.
Collapse
Affiliation(s)
- R A Curtis
- Faculty of Veterinary Science, University of Sydney, NSW 2006, Australia
| | | | | | | | | |
Collapse
|
32
|
Tan RHH, Dowling BA, Dart AJ. High-speed treadmill videoendoscopic examination of the upper respiratory tract in the horse: the results of 291 clinical cases. Vet J 2004; 170:243-8. [PMID: 16129344 DOI: 10.1016/j.tvjl.2004.06.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/28/2004] [Indexed: 10/26/2022]
Abstract
The purpose of the study was to describe the prevalence of upper airway abnormalities and establish if any significant associations existed between study variables and the two most frequently identified disorders; axial deviation of the aryepiglottic folds and dorsal displacement of the soft palate. The clinical records and video-recordings of all horses referred for upper respiratory tract evaluation during high-speed treadmill videoendoscopy between November 1997 and September 2003 were reviewed. Of 291 horses included in the study, 265 underwent resting endoscopy and 42% (112/265) had a recognised abnormality. More than one abnormality was identified in 49% of horses. In general, horses referred specifically for evaluation of a respiratory tract noise were more likely to have an abnormality detected during exercise than those referred for high-speed treadmill videoendoscopy for poor performance (82% versus 49%). Axial deviation of the aryepiglottic folds (105/192, 55%) was the most common abnormality identified, followed by dorsal displacement of the soft palate (74/192, 39%) and idiopathic left laryngeal hemiplegia (65/192, 34%). Other abnormalities identified included arytenoid collapse, vocal fold collapse, dynamic pharyngeal collapse, epiglottic fold entrapment, epiglottic retroversion, rostral displacement of the palatopharyngeal arch and right laryngeal hemiplegia. In horses with axial deviation of the aryepiglottic folds there was a significant association between the increasing severity of the deviation and the increasing number of abnormalities detected. There were no other associations found. High-speed treadmill videoendoscopy is an important component of the evaluation of poor performance, particularly in horses with a history of respiratory noise. The occurrence of multiple abnormalities in a large proportion of horses suggests that high-speed treadmill videoendoscopy should be recommended, where possible, to make an accurate diagnosis, advise on appropriate treatment options and provide a prognosis for affected horses.
Collapse
Affiliation(s)
- Rachel H H Tan
- University Veterinary Centre Camden, Faculty of Veterinary Science, The University of Sydney, Werombi Road, Camden, New South Wales, 2570, Australia
| | | | | |
Collapse
|
33
|
|
34
|
Kraus BM, Parente EJ, Tulleners EP. Laryngoplasty with ventriculectomy or ventriculocordectomy in 104 draft horses (1992-2000). Vet Surg 2003; 32:530-8. [PMID: 14648531 DOI: 10.1111/j.1532-950x.2003.00530.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate efficacy and safety of laryngoplasty with vetriculectomy (VE) or ventriculocordectomy (VCE) for treatment of laryngeal hemiplegia (LH) in draft horses. STUDY DESIGN Retrospective study. SAMPLE POPULATION One hundred four draft horses used for competitive hitch competitions. METHODS Medical records and postoperative endoscopy for competitive hitch draft horses diagnosed with left LH and treated with laryngoplasty and VE or VCE between January 1992 and December 2000 were reviewed. Follow-up information was obtained from telephone interviews with owners and trainers, and performance scores of 1 to 3 were assigned in which 1 was defined as a horse that was unable to perform (abnormal respiratory noise with or without exercise intolerance), 2 was able to perform but not for its intended use (exercise tolerant but abnormal respiratory noise), and 3 was performing as expected for its intended use (exercise tolerant, no abnormal respiratory noise). RESULTS One hundred four horses that had 111 laryngoplasty procedures were included. All horses had preoperative performance scores of 1. Follow-up information was available for 79 horses. Improvement in postoperative performance (exercise tolerant, with or without abnormal respiratory noise) was reported in 92% of horses. Respiratory noise was eliminated in 72% (57 horses) of horses. Postoperative performance scores were the following: 3 in 57 (72%) horses, 2 in 16 (20%) horses, and 1 in 6 (8%) horses. There was no significant difference in postoperative performance based on preoperative grade of LH. There was a trend for horses with >/=70% of possible maximal abduction postoperatively to have a performance score of 3. Postanesthetic complications included prolonged recovery (4 horses, 4%) and myopathy or neuropathy (7 horses, 7%). One of these horses was killed because it did stand; triceps myopathy and encephalopathy were confirmed on necropsy. CONCLUSIONS Laryngoplasty with VE or VCE is an effective and safe procedure for the treatment of LH in the draft horse. Repeat laryngoplasty can be performed successfully, with good performance outcome after laryngoplasty failure. Complications associated with general anesthesia and laryngoplasty in draft horses are higher than reported for light breed horses under similar conditions. CLINICAL RELEVANCE For LH, laryngoplasty with VCE or VE under general anesthesia is recommended to eliminate abnormal respiratory noise and improve performance in most competitive hitch draft horses.
Collapse
Affiliation(s)
- Beth M Kraus
- Department of Clinical Studies, New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA
| | | | | |
Collapse
|