The medication violations in racehorses at Louisiana racetracks from 2016 to 2020.
Abstract: The number of publications for most common drug violations in racehorses is limited. This study reports the most common medication violations in racehorses at four major racetracks in Louisiana between 2016 and 2020. During this 5-year period, 27,237 blood samples and 25,672 urine samples collected during the course of normal race meeting activities were analysed by initial screening procedure utilizing Liquid Chromatography Mass Spectrometry (LC-MS/MS). Following initial screening, suspect samples were subject to quantitative or semi- quantitative confirmation analysis by LC-MS/MS. The total number of violations reported was 534 (1.01% of the total number of specimens analysed). The total number of violations reported in Thoroughbred horses was 210 while the total number of violations reported in Quarter Horses was 324. The percentage of total violations was %0.59 for all the specimens analysed in Thoroughbred horses while this percentage was %1.9 for all the specimens analysed in Quarter Horses during this 5-year period. The most frequent violations included the overages (concentrations of permitted medications equal to or exceeding the set threshold) of clenbuterol (165 violations), non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone (73 violations), combination of phenylbutazone with flunixin (45 violations) and muscle relaxant methocarbamol (40 violations). The total number of violations were relatively low during 5-year period, but wide varieties of medications with different pharmacological actions were confirmed in performance horses in Louisiana. The most frequently reported violations in Louisiana were for permitted therapeutic medications (clenbuterol, phenylbutazone, flunixin methocarbamol) with established threshold and/or withdrawal guidelines in racehorses.
© 2021 The Authors. Veterinary Medicine and Science published by John Wiley & Sons Ltd.
Publication Date: 2022-01-06 PubMed ID: 34989156PubMed Central: PMC8959255DOI: 10.1002/vms3.724Google Scholar: Lookup
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- Journal Article
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Summary
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This research study investigates the most common medicine violations in racehorses at the four major racetracks in Louisiana between 2016 and 2020. The study analyzed numerous blood and urine samples from racehorses to detect violations, discovering relative low rates of violations, most of which were for permitted therapeutic medications.
Overview of the Research
- This study examined prevalent medication violations in Louisiana racehorses within a five-year window from 2016 to 2020.
- Nearly 27,237 blood samples and 25,672 urine samples from horses taken during normal racing activities were analyzed.
- Liquid Chromatography Mass Spectrometry (LC-MS/MS) was used for both initial screening and for further confirming analysis of suspect samples.
Findings
- In total, 534 violations were reported, which represented a little over 1% of the total number of specimens tested.
- Among horse breeds, Quarter Horses reported more violations at 324 as compared to 210 in Thoroughbreds.
- However, as a percentage of total specimens analyzed, Quarter Horses had a higher violation rate at 1.9%, compared to 0.59% for Thoroughbreds.
Common Violations
- The analysis found that the most common violations were for overages – quantities of permitted medication exceeding the set threshold. These included:
- Clenbuterol, with 165 reported violations
- Non-steroidal anti-inflammatory drugs (NSAIDs) such as phenylbutazone, with 73 violations
- The combination of phenylbutazone with flunixin resulted in 45 violations
- Muscle relaxant methocarbamol with 40 violations
Conclusions of the Study
- Even though the number of medication violations over the span of five years was relatively low, a wide variety of drugs with different pharmacological effects were confirmed in the performance of horses in Louisiana.
- The most frequent violations were for permitted therapeutic medications (clenbuterol, phenylbutazone, flunixin methocarbamol) which have established threshold and/or withdrawal guidelines in racehorses.
Cite This Article
APA
Waller P, Lomnicka I, Lucas C, Johnson S, Dirikolu L.
(2022).
The medication violations in racehorses at Louisiana racetracks from 2016 to 2020.
Vet Med Sci, 8(2), 553-560.
https://doi.org/10.1002/vms3.724 Publication
Researcher Affiliations
- Equine Medication Surveillance Laboratory (EMSL), Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
- Equine Medication Surveillance Laboratory (EMSL), Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
- Equine Medication Surveillance Laboratory (EMSL), Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
- Equine Medication Surveillance Laboratory (EMSL), Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
- Equine Medication Surveillance Laboratory (EMSL), Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
MeSH Terms
- Animals
- Chromatography, Liquid / veterinary
- Clenbuterol
- Horses
- Methocarbamol
- Phenylbutazone
- Tandem Mass Spectrometry / veterinary
Conflict of Interest Statement
The authors declare no conflict of interest.
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Citations
This article has been cited 3 times.- Roccaro M, Rinnovati R, Stucchi L, La Rocca F, Cascio G, Peli A. Survey on 9 years of anti-doping controls in horse races in Italy. Equine Vet J 2025 Nov;57(6):1592-1599.
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- Scantamburlo G, Nofziger C, Paulmichl M, Vanoni S. Genetic analysis of the equine orthologues for human CYP2D6: unraveling the complexity of the CYP2D family in horses. Front Vet Sci 2023;10:1188633.
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