Probably not real long. We vaccinate all of our calves at around 3 mos and again at 6-7 mos weaning. In our part of Texas we use 3 different vaccinations + injectible de-wormer. The vaccinations we do are: (1) IBR, BVD, PI3; (2) 7-way Blackleg; (3) Pasteurella/Haemolytica. Then, Ivomec Plus injectible.
Heifers are vaccinated by the Vet for Brucellosis between weaning age and 12 mos. old. Vet must do it.