Abstract
The studies described in this report were performed to determine, whether it is possible to produce live virus vaccines without serum or fractions thereof used during any cell or virus passage, thus completely serum-free. Two viruses were included in the experiments: Bovine Herpesvirus 1 (BHV-1) and Bovine Parainfluenza type 3 virus (PI3). Both viruses were found to grow to satisfactory titers, and to be stable after freeze-drying and subsequent storage at temperatures of +4 degrees C and -20 degrees C for at least one year. Moreover, a vaccine containing serum free produced BHV-1 was tested in a vaccination-challenge experiment. For comparison, a vaccine batch with BHV-1 grown in serum-containing cell culture medium was included in the study. Both vaccine preparations performed equally well and both met the strict requirements as laid down in the European Phamacopeia. Moreover, in two separate experiments the safety of serum-free produced BHV-1 and PI3 after overdose and repeated administration even in very young calves and even after four administrations has been demonstrated. This report is the first, which to our knowledge demonstrates the safety and efficacy of serum-free produced live vaccines in the target animal as well as the stability of these products.