Two endurance horses have failed drugs tests after races in Dubai and Qatar, the FEI announced.
The first involved Thiyya Du Moriter, a horse registered in the United Arab Emirates. It tested positive for the banned substance trendione, an androgen prohormone as well as a metabolite of the anabolic steroid trenbolone.
The person responsible was listed as Abdulla Rashid Al Naqbi, a UAE-registered rider.
The pair had competed in a CEI2* 120km endurance race in Dubai on March 17 this year.
The second case involved a CEI1* 100km endurance race in Doha, Qatar, on the same day.
The Qatar-registered horse Al Baaz tested positive for the banned substance diisopropylamine, a vasodilator used in the treatment of peripheral and cerebral vascular disorders.
The rider was listed as Qatar-registered Hamad Fahaf A. A. Al Marri.
The riders have been provisionally suspended from the date of notification, April 19, until the FEI Tribunal delivers its decisions in the cases. The horses have been provisionally suspended for two months.
In a previously announced case involving the horse Sohair de Bruyere, the FEI has announced the provisional suspension of a trainer, Hassan Khamis Mohammed A. Al Shahwani, of Qatar, as an additional person responsible.
The case relates to Sohair de Bruyere competing in a CEI2* 120km endurance ride in Doha, Qatar, on January 20 this year. The horse, ridden by Russian-registered Elizaveta Minina, tested positive for testosterone.