|Briggs, Robert - Bob|
Submitted to: Vaccine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/25/2003
Publication Date: 1/1/2004
Citation: Fulton, R.W., Briggs, R.E., Payton, M.E., Confer, A.W., Saliki, J.T., Ridpath, J.F., Burge, L.J., Duff, G.C. 2004. Maternally derived humoral immunity to bovine viral diarrhea virus (BVDV)1a, BVDV1b, BVDV2, bovine herpesvirus-1, parainfluenza-3 virus bovine respiratory syncytial virus, Mannheimia haemolytica and Pasteurella multocida in beef calves, antibody decline by half-life studies and effect on response to vaccination. Vaccine. 22(5-6):643-649. Interpretive Summary: In excess of 90% of the annual U.S. calf crop receives anti-viral vaccination as an important part of health management. Optimal timing of vaccination, and proper design of the vaccines is crucial to the success of vaccine treatments. The influence of maternal antibody on the vaccinal induction of immunity was studied in a group of beef calves with diverse pre-existing specific antibody levels within a single herd. Calves with high pre-existing antibody levels tended to not respond to a killed-virus vaccine, and the predicted time until those calves would be expected to be responsive to vaccination varied considerably. The findings imply that the vaccination program for cows must be considered in order to produce calves which can be efficiently vaccinated, information useful to both cattle producers and vaccine manufacturers.
Technical Abstract: The passive immunity transferred to calves from their dams investigated in a beef herd to determine half-life of antibody, estimated time to seronegative status and effect on immunization. One hundred two beef calves in a commercial ranch under standard management conditions were utilized. Samples were collected at branding (day 0). This was the first possible date to collect samples postcalving. This was approximately 2 months postcalving, and days 95 and 116. The calves were divided into two groups: vaccinates (51) and nonvaccinates (51). The calves were vaccinated with a commercial inactivated viral vaccine containing bovine viral diarrhea virus (BVDV)1a, BVDV2, bovine herpesvirus-1 (BHV-1), parainfluenza-3 virus (PI-3V), and bovine respiratory syncytial virus (BRSV) on days 0 and 95. Half of the vaccinated and unvaccinated calves also received one dose of an experimental Mannheimia haemolytica and Pasteurella multocida vaccine at day 95. Serums were tested for neutralizing antibody titers to BVDV1a, BVDV1b, BVDV2, BHV-1, PI-3V, and BRSV. Antibodies were detected by ELISA to M. haemolytica whole cell, M. haemolytica leukotoxin, and P. multocida outer membrane protein (OMP). The mean half-life of viral antibodies in nonvaccinated calves to each virus was: BVDV1a, 23.1 days (d); BVDV1b, 22.8d; BVDV2, 22.9d; BHV-1, 21.2d; PI-3V, 30.3d; and BRSV, 35.9d. The mean half-life of viral antibodies was greater for vaccinates than for nonvaccinates for all viruses except BRSV. The calculated mean time to seronegative status for nonvaccinates based on titers at day 0 was; BVDV1a, 192.2 d; BVDV1b, 179.1d; BVDV2, 157.8d; BHV-1, 122.9d; PI-3V, 190.6d; and BRSV, 186.7d. There was an active immune response after vaccination with two doses to all the viruses, except BRSV. Mean antibody titers of vaccinates at day 116 were statistically higher than nonvaccinates for all viruses except BRSV. However on an individual calf basis there were few seroconversions (four-fold rise or greater to BVDV1a, BVDV1b, BVDV2, PI-3V, or BRSV; or two-fold rise for BHV-1) in the presence of viral antibodies. The predicted time of seronegative status for a group of calves for vaccination programs may not be appropriate as there may be a range of titers for all calves at day 0. In this study the range for BVDV1a was 16-16,384; BVDV1b, 8-8192; BVDV2, 0-8192; BHV-1, 0-935; PI-3V, 8-2048; and BRSV, 8-4096. Using the half-life of 23d for BVDV1a, the time thereafter for seronegative status would be 46 and 299 d compared to the calculated date of 192.2d using the mean of estimated time to seronegative status for all the calves. There was an active humoral response in the vaccinated calves to M. haemolytica and P. multocida. Cowherd humoral immunity based on serum antibodies should be monitored as it may relate to transfer of maternal antibodies to calves. Exceptionally high levels of viral antibodies transferred to calves could interfere with the antibody response to vaccination.