Development of Bovine Viral Diarrhea Live Virus Vaccine

Abstract

Lyophilized bovine viral diarrhea (BVD) live virus vaccine was prepared tentatively from attenuated BVD virus cultured in ST cells. Neutralizing antibody produced after vaccination decreased hardly in titer even after one year. When vaccinated at 1-9 months of pregnancy, 12 cows gave birth to normal young. Vaccinated cattle induced no contact infection. No accident was observed among about 1, 500 cattle inoculated in the field. Antibody response was seen in 99.1%. No decrease in infective titer occurred in the vaccine stored at 4°Cfor 18 months, or in the thawed vaccine stored for 2 days.