Antibody responses by cattle after vaccination with commercial viral vaccines containing bovine herpesvirus-1, bovine viral diarrhea virus, parainfluenza-3 virus, and bovine respiratory syncytial virus immunogens and subsequent revaccination at day 140

Calves were vaccinated with four different commercial viral vaccines containing bovine herpesvirus-1 (BHV-1), bovine viral diarrhea (BVDV), parainfluenza-3 virus (PI-3V), and bovine respiratory syncytial virus (BRSV) immunogens. For the initial vaccination certain vaccines were given twice (days 0 and 28), whereas other vaccines were given on day 0. The calves received another injection on day 140 with the vaccine originally given on day 0. The sera were collected at days 0, 7, 14, 21, 28, 42, 56, 84, 112, 140, 154, 168, and 196 and assayed for viral neutralizing antibodies. The calves were seronegative to BHV-1, BVDV, and BRSV at the onset of the experiment; however, the calves were PI-3V antibody positive due to prior active infection. The commercial vaccines were: (I) inactivated; (II) modified live virus (MLV); (III) combination of chemically altered live virus, MLV, and inactivated virus; and (IV) combination of inactivated and MLV. Among the vaccine groups there were differences in onset and duration of antibodies as measured by geometric mean titers to each immunogen in postvaccination collection dates compared to day 0 titers; and likewise compared to day 140 titers after revaccination at day 140. There were also differences in antibody titers to the various viruses among the vaccine groups on specific collection dates. All four vaccines induced increased BHV-1 antibodies by day 14 after the initial injection. The antibody titers induced by MLV BHV-1 and the chemically altered BHV-1 vaccines had greater duration than those induced by the inactivated vaccine. Initially the BHV-1 antibody titers were higher on day 14 resulting from the initial injection of the MLV vaccines; yet the antibodies were increased at day 42 after two doses of inactivated or chemically altered BHV-1. The BVDV antibodies developed later than those induced by BHV-1 vaccines. The MLV vaccine and one inactivated vaccine, IV, induced increased BVDV titers by day 28, whereas the two other inactivated vaccines, I and III, induced increased titers by day 42. These increased BVDV titers were maintained through day 140. The vaccines containing MLV BRSV components induced BRSV antibody titers more rapidly and at higher titers by day 7 after vaccination compared to the inactivated vaccine. Vaccination of calves with prior actively acquired PI-3V resulted in higher PI-3V antibody titers by the inactivated vaccine at day 7 compared to the MLV vaccine, II. All four vaccines induced increas