I have a 300 pound steer, Holstein, and I have noticed lately that he has very loose stools. They have not been vaccainated. At feeding time he goes to the dock but does not eat alot. He is alert and does not seem depressed. He was banded awhile back and is in the final stages of castration. The runs started shortly after introducing a bucket calf which was bought at a sale barn. How do I address the runs and should I vaccainate him against BVD or other viruses. I have given him antibotics the last couple of days but it does not seem to be helping.