There are several things that can be done to ensure a pathogen-free reproductive herd. First, make sure that you are purchasing animals from well-managed and reputable herds. Make sure that before you purchase the animals you have them tested for any pathogens. Once you have the animals, you need to quarantine them so they have no contact with other animals in your herd. This means no nose-to-nose contact for 60 days. While the animals are in quarantine, administer vaccines and treat for any other parasites. Once the 60-day period is up and the animals are released into your herd, to ensure the health of all the animals, it is important to maintain a proper vaccination program, especially for BVD.
Take the time (and the investment) to visit with your local large animal veterinarian about an appropriate herd health program that is designed for your location and your herd situation.