The Oklahoma Quality Beef Network (OQBN) Vac-45 Program is a beef calf preconditioning program implemented by Oklahoma State University Extension in partnership with the Oklahoma Cattlemen’s Association, with the goal of providing a value-added marketing opportunity for cow-calf producers. For calves to become OQBN Vac-45 certified, they must be weaned for at least 45 days and receive two rounds of vaccinations (initial vaccination and booster) against pathogens responsible for bovine respiratory disease (BRD) and clostridial bacteria that cause blackleg. Viral pathogens responsible…