Individuals with a final titer of 0. (A) Bovine viral diarrhea virus type 1 (n = 367), (B) bovine viral diarrhea virus type 2 (n = 100), and (C) bovine herpesvirus 1 (n = 468). Average titer level across all individuals measured is plotted in green. (D) Bovine respiratory syncytial virus (n = 132) shows individuals with the minimum titer calculated at wk 6 (3 on a log2 scale). Although it is not the same trend as shown in panels A, B, and C, it was included to allow comparison.