With summer officially underway, HIWU would like to remind horsemen and veterinarians of regulations regarding the administration of electrolytes within 48 and 24 hours of a race or Vets’ List workout: Permitted at any time: • Salt and mineral blocks. • Unsupplemented isotonic electrolyte solutions that may be consumed by free choice by the horse, i.e., providing a second water bucket in the stall that has been supplemented with electrolytes. Permitted up to 24 hours before a race or Vets’ List workout: • Electrolytes that are administered orally. Examples that fall in this category include powders that are top-dressed or mixed in the feed, as well as electrolytes administered via paste. • Unsupplemented isotonic electrolyte solutions administered intravenously such as Lactated Ringer’s solution. • Electrolyte patches.* Permitted up to 48 hours before a race or Vets’ List workout: • Electrolytes administered via nasogastric (stomach) tube. *Since electrolyte patches are not consumed “free choice” by a horse in feed or water, their use is prohibited within 24 hours of a race or Vets’ List workout The restrictions above only apply in relation to races and Vets' List workouts. Outside of those circumstances, electrolytes may be administered at any time. The above information can also be found in HIWU’s Electrolyte Guidance resource on our website and app. Please direct any questions to sciencesupport@hiwu.org. Yours, The HIWU Team

In recent months, HIWU has adjudicated several cases under the Anti-Doping and Medication Control (ADMC) Program related to adenosine, a vasodilator, and Hemo 15, a foreign product that lacks FDA approval. Neither substance has any valid veterinary use in the racehorse. Both substances are categorized as an S0 Non-Approved Banned Substance and therefore are prohibited from Use in a Covered Horse or Possession by a Covered Person at all times. Hemo 15 and any compounded product mimicking Hemo 15, as well as any products containing adenosine, adenosine monophosphate (AMP), or adenosine triphosphate (ATP)* should be disposed of immediately. As a reminder, the Presence, Use, Administration, Possession, or Trafficking of any Banned Substance is subject to a period of Ineligibility of up to two years, a fine of up to $25,000, the disqualification of race results (as applicable), and public disclosure. Horsemen or veterinarians with questions should reach out to sciencesupport@hiwu.org. *Adenosine is also a component of AMP and ATP.

The Horseracing Integrity & Welfare Unit (HIWU) announced today the release of its 2024 Annual Report. The full report is available here. The Annual Report details HIWU’s organization-wide activities as the independent enforcement agency of the Horseracing Integrity and Safety Authority’s (HISA) Anti-Doping and Medication Control (ADMC) Program. Among the highlights are statistics on testing, results management, the adjudication of cases, investigations, and educational efforts. The 2024 Annual Report introduces expanded testing statistics by state and racetrack, including the number of samples collected for each test type. Additionally, it reveals shorter turnaround times for results reporting compared to 2023, showcases the impact of HIWU’s investigative efforts, and reports a consistently low rate of Adverse Analytical Findings for Controlled Medications, demonstrating that the vast majority of Covered Persons are complying with the ADMC Program Rules. “HIWU’s successes in 2024 reflect the dedication of our team and the entire Thoroughbred industry,” said Ben Mosier, executive director for HIWU. “The collaboration between HIWU and industry stakeholders enabled us to build on the ADMC Program’s strong foundation that was established in 2023. HISA’s reported record-low fatality numbers last year indicate that we are fulfilling our mandates to enhance equine safety and welfare and promote the integrity of racing.” All Annual Reports and Quarterly Statistics are archived in the About Us section of the HIWU website at hiwu.org for viewing anytime. About the Horseracing Integrity & Welfare Unit The Horseracing Integrity & Welfare Unit (HIWU) was established in 2022 by Drug Free Sport International to administer the rules and enforcement mechanisms of the Horseracing Integrity and Safety Authority’s (HISA) Anti-Doping and Medication Control (ADMC) Program. The ADMC Program established a centralized testing and results management process that applies uniform penalties for violations efficiently and consistently across all American Thoroughbred racing jurisdictions that HISA governs. As the enforcement agency of the ADMC Program, HIWU oversees all testing processes, including the selection of horses to be tested, training of sample collection personnel, and chain-of-custody procedures. Additionally, HIWU is charged with industry/stakeholder education, laboratory accreditation, results management and adjudication, and investigations. For more information, please visit hiwu.org. Contact: Alexa Ravit, HIWU Director of Communications & Outreach  (816) 516-9572  aravit@hiwu.org