Development of tick fever immunity after vaccination
Following a single vaccination, immunity to tick fever takes a number of weeks to develop, but the immunity is usually lifelong.
Cattle can be at risk of developing tick fever if exposed to ticks before the vaccine immunity has taken effect. This is only of concern in animals older than 9 months of age.
The most common type of tick fever, Babesia bovis, is transmitted 1–3 days after the attachment of the larval (seed) tick. Pour-on and injectable tick control chemicals do not kill seed ticks soon enough to prevent the transmission of Babesia bovis. Commonly used dip chemicals have short residual activity.
Protecting cattle while immunity develops
You can minimise the risk of tick fever in introduced cattle by vaccinating at least 60 days before cattle enter tick-infested areas. This allows time for immunity to develop for all 3 tick fever organisms. If a 60-day delay in moving cattle is not possible, then:
- delay movement for 3–4 weeks after vaccination to allow immunity to both species of Babesia to develop
- isolate introduced animals from other local cattle for 60 days after vaccination to help prevent transmission of anaplasmosis
- keep animals tick-free before and for 28 days after vaccination when vaccinating animals that have been introduced into a tick-infested area. This is very difficult to achieve, so you must monitor the cattle carefully during the period when immunity is developing.
Moving cattle before immunity has developed
If it is not possible for you to delay the movement of cattle, move them before day 7 or from 21 to 30 days after vaccination.
These 'windows' prevent animals being transported and stressed during reaction periods, but the risk of disease from field infection still exists until immunity develops.
- Learn more about managing tick fever in cattle.