QR448(a)

**QR448(a)** is an investigational veterinary antiviral botanical mixture developed by Quigley Pharma for prevention and treatment of avian infectious bronchitis in chickens. It contains proprietary oleoresins and essential oils derived from botanicals and was evaluated primarily in commercial broiler chickens against avian infectious bronchitis virus. In vitro and in vivo studies found that spray administration before viral exposure reduced clinical signs, lesions, tracheal viral RNA, and flock transmission, with activity against Massachusetts- and Arkansas-type infectious bronchitis virus. Its activity was greatest before viral attachment and entry, consistent with a direct virucidal effect on the virus.