We have raised a young herd of steers (now 6-8mo.old) and recently purchased 7 heiffers that are around 10 mo. old. In the original steers we brought to the farm, we found that they were infected with IBR. They almost went blind (as we were treating for pink eye) before someone told us what we were dealing with. But now, have vaccinated the whole herd once and are preparing to administer the second vaccination. Our question is this: Once the second vaccination is done, will the heiffers pass the virus onto their newborns and how long after treatment before breeding? Will our bull also be a carrier?