The advantage of killed vaccine is more safety as a result of inactivation of live viral strains. Therefore, it can be administrated to pregnant animals. There are many disadvantages of killed BVDV vaccines, it is more expensive due to large amounts of virus are required for preparation of each dose and adjuvant should be added to the vaccine. In addition, the duration of immunity is shorter and there are requirement for injection two doses to initiate protection (Fulton 2005).
The killed vaccines could be administered to pregnant cows to decrease the incidence of abortion by injection of two doses about two to three weeks apart starting after pregnancy or one month before giving birth (Radostits et al. 2007). 2.8.4.