Pre-Calving
This annual booster is to protect the unborn calf and provide for the transfer of antibodies from the cow to the calf through colostrum, protecting the calf for a period after birth. This ‘passive’ immunity protects the calf until vaccination can be undertaken. Colostral antibody wears off in the first 2-3 months of life. Read the label to ensure that the vaccine you are using will work if given to calves with colostral immunity and to determine the youngest age that you can vaccinate cattle.
Pre-Joining
The timing of this annual booster is to protect the cow from infection during pregnancy. This is particularly important for Pestigard® to minimise the production of persistently infected animals. For bulls, this ensures immunity to reproductive disease is at optimal levels prior to exposure to females and minimises transmission of reproductive disease during joining.
NOTE: Some vaccines are single dose. They can trickle antigen into the body resulting in the equivalent of a primary and secondary response from one dose of vaccine (for example Longrange® and Vibrovax®). They do however require annual or biennial boosters (5mL of Vibrovax® for heifers >18 months).