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Equine veterinary journal2006; 38(4); 300-304; doi: 10.2746/042516406777749191

Effect of tracheal mucus and tracheal cytology on racing performance in Thoroughbred racehorses.

Abstract: Accumulations of mucus within the trachea are often found during endoscopic examinations of the airways of poorly performing racehorses, but the clinical importance of this finding is unknown. Objective: To determine the effect of tracheal mucus, pharyngeal lymphoid hyperplasia (PLH) and cytological indices of tracheal aspirate on racing performance in Thoroughbred horses assessed by race place and whether the horse was raced. Methods: Endoscopic examination of the nasopharynx, larynx and trachea was performed, and a tracheal aspirate obtained monthly at Thistledown racetrack from April to December, 2002 and 2003. Horses received a score of 0-4 for the degree of PLH and 0-4 for the amount of mucus visible in the trachea. The tracheal aspirate was assessed for turbidity, and total and differential cell counts. Generalised estimating equations models were used as repeated measures models for each risk factor and the level of association assessed through the risk factor's P value in the model. Results: Moderate to severe tracheal mucus (2-4) was a risk factor for poor racing performance. There was no association between degree of PLH, cell counts or turbidity of tracheal wash fluid and racing performance. However, horses that raced had higher total neutrophil counts in tracheal wash aspirates than horses that did not race. Conclusions: Grades 2-4 tracheal mucus should be considered a potential cause of poor racing performance in Thoroughbred horses. Conclusions: Because moderate to severe tracheal mucus accumulation, and not increased tracheal neutrophils, was a risk factor for poor racing performance, functionally significant airway inflammation may best be confirmed by the presence of mucus rather than increased number of neutrophils in the trachea.
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Publication Date: 2006-07-27 PubMed ID: 16866195DOI: 10.2746/042516406777749191Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article studies the connection between tracheal mucus and the racing performance of Thoroughbred horses. It illustrates that moderate to severe tracheal mucus accumulation can affect the racehorses’ performance negatively.

Objective and Methodology

The objective of the study was to ascertain the impact of tracheal mucus, pharyngeal lymphoid hyperplasia, and cytological indices of tracheal aspirate on the racing performance of Thoroughbred horses. The indicators used to evaluate the performance were the racing position and whether the horse actually raced.

For the research, an endoscopic examination of the horse’s nasopharynx, larynx and trachea was performed, and monthly tracheal aspirates were collected at the Thistledown racetrack from April to December during 2002 and 2003. These horses were then rated based on a scale of 0-4 for the degree of pharyngeal lymphoid hyperplasia and volume of mucus in the trachea.

Findings

After analyzing the horses’ endoscopy results and their performance metrics, the researchers found a correlation between the accumulation of tracheal mucus and the racing performance of the horses. This basically means that the presence of a moderate to significant amount of mucus in the trachea (2-4 score), can cause the horse to underperform in the races.

However, the data did not draw a significant link between the horses’ racing performance and the degree of pharyngeal lymphoid hyperplasia, cell counts or turbidity of tracheal wash fluid. Further, it was noticed that the horses that raced had a higher total neutrophil count in the tracheal wash aspirates compared to the horses that did not race.

Conclusion

Based on the research findings, it can be concluded that Thoroughbred horses with grade 2-4 tracheal mucus are likely to have poor racing performance. It was also pointed out that the presence of mucus rather than increased number of neutrophils in the trachea is a better determinant of functionally notable airway inflammation. This indicates that the measure of mucus content could be one of the potential factors assessed for a horse’s health and racing prospective.

Cite This Article

APA
Holcombe SJ, Robinson NE, Derksen FJ, Bertold B, Genovese R, Miller R, de Feiter Rupp H, Carr EA, Eberhart SW, Boruta D, Kaneene JB. (2006). Effect of tracheal mucus and tracheal cytology on racing performance in Thoroughbred racehorses. Equine Vet J, 38(4), 300-304. https://doi.org/10.2746/042516406777749191

Publication

Equine veterinary journal
ISSN: 0425-1644
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 38
Issue: 4
Pages: 300-304

Researcher Affiliations

Holcombe, S J
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824, USA.
Robinson, N E
    Derksen, F J
      Bertold, B
        Genovese, R
          Miller, R
            de Feiter Rupp, H
              Carr, E A
                Eberhart, S W
                  Boruta, D
                    Kaneene, J B

                      MeSH Terms

                      • Age Factors
                      • Analysis of Variance
                      • Animals
                      • Cough / pathology
                      • Cough / veterinary
                      • Endoscopy / methods
                      • Endoscopy / veterinary
                      • Female
                      • Horse Diseases / physiopathology
                      • Horses
                      • Hyperplasia / pathology
                      • Hyperplasia / veterinary
                      • Lymphoid Tissue / pathology
                      • Male
                      • Mucus / metabolism
                      • Neutrophils
                      • Physical Conditioning, Animal / physiology
                      • Respiratory Tract Diseases / pathology
                      • Respiratory Tract Diseases / physiopathology
                      • Respiratory Tract Diseases / veterinary
                      • Risk Factors
                      • Running
                      • Sports
                      • Time Factors
                      • Trachea / cytology
                      • Trachea / pathology

                      Citations

                      This article has been cited 25 times.
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