Marc Caldwell presentation at 2019 Applied Reproductive Strategies in Beef Cattle
The fetus is the most susceptible to disease of any animal on the farm. The cow is basically a barrier for the fetus.
Good biosecurity practices are more impactful (important) than a vaccine protocol. But, in reality, the two work together.
Most disease problems are the results of purchasing practices. (Buying a BVD-PI cow for example.)
Modified live vaccines are not 100% safe. MLV vaccines can only be in pregnant animals if she has previously been vaccinated with a MLV. For pre breeding, should be used 30 days, and preferably 45 days, before the breeding season.
Killed vaccines are not 100% effective.
Two doses in time (2 to 4 weeks apart based on label) is still the best. The memory B and T cells created from two doses are what provide long term, lasting immunity.
Why do we use the same vaccines year after year? There is a new approach called Prime Boost. In this approach an animal receives two rounds of modified live vaccine. Then sometime in the future the animal receives an i…