Modified Live compared to Killed Vaccines for the Cow Herd
Properly administered and boostered modified live vaccines cause cell
-mediated immunity in cattle. The respiratory diseases, bovine viral diarrhea (BVD), infectious bovine Rhinotracheitis (IBR), Parainfluenza 3 (PI3), and bovine respiratory syncytial virus (BRSV) all have been shown to have an impact on reproductive performance of infected cowherds. With the close proximity of herds to each other in the Southern region of the United States, it is difficult to isolate cattle enough to assure no transmission of these viral diseases. Therefore immunization with readily available vaccines becomes the method of choice for protecting the herd from devastating impacts of early embryo loss, abortion, or weak calves due to these viruses. Once the decision to protect the herd with immunizations has been made, the next decision is the type of vaccine that is employed. The following table was compiled by Dr. Ronald D. Schultz and presented at the 1993 meeting of the American Association of Bovine Practitioners. This is an excellent comparison of Modified Live Vaccines (MLV) and Non-Infectious or killed products (NI).