Figure 4
Reduced virus shedding of rNDV-BRSV Fopt vaccinated colostrum-deprived calves. Treatment groups of calves included: unvaccinated, uninfected controls (n = 5); intranasal (i.n.) allantoic fluid vaccinated (mock vaccine control) and BRSV challenged (n = 6); i.n. wtNDV-vaccinated and BRSV challenged (n = 6); i.n. rNDV-BRSV Fopt vaccinated and BRSV challenged (n = 6). Prior to vaccination, weekly following vaccination, and each day after experimental challenge, nasal swab samples were collected and placed in MEM containing antibiotics/antimycotics. Samples were vortexed and clarified by centrifugation and supernatants used to inoculate BT cells for virus isolation. Daily observations for cytopathic effect were conducted and recorded for 7 days following inoculation of cells. Results shown are the percentages of calves in each group which were positive for virus isolation.
