The Ranchers Cattleman Action Legal Fund United Stockgrowers of America (R-CALF USA) has submitted a request to USDA’s Center for Veterinary Medicine requesting emergency approval for the medication buparvaquone to treat cattle infected with theileriosis, the disease transmitted by the Asian longhorned tick (ALHT).
The letter, penned by R. M Thornsberry, chairman of the R-CALF USA Animal Health Committee, asks the FDA to take action to combat the disease, which has been spreading in the United States since 2017 when its carrier was introduced. Since then, the ALHT has been identified in 21 states, most recently as far west as Kansas.
“As a food animal veterinarian, I can prescribe appropriate treatment protocols for tick control, but I must watch my client’s cattle die because I have no approved therapeutic protocols to treat a properly diagnosed case of theileriosis,” Thornsberry writes.
Buparvaquone has a history of use for the treatment of theileriosis in other regions including Asia, Africa, Pacific Island nations and the Middle East. R-CALF USA proposes extended withdrawal times to ensure food safety.
Signs of theileriosis infection in cattle include:
- Weakness
- Fever
- Loss of appetite
- Difficulty breathing
- Reduced milk production
- Foamy nasal discharge
Pregnant cows and calves are most susceptible to infection, and once infected, cattle can be lifetime carriers.
As the ALHT continues to expand its range, the approval of this medicine could be very important for nationwide cattle health.
For more information:
Theileria and the Asian Longhorned Tick: What Beef Producers Need to Know


