Ticks and tick fever in livestock

Flooding may drown ticks, but tick numbers and the risk of tick fever can increase with the associated wet and warm weather. This is particularly a problem if tick numbers have previously been low, as only a small proportion of the herd may have developed immunity to tick fever. It is recommended that you increase monitoring for ticks and tick fever, and take action as necessary.

Symptoms of tick fever

Tick fever is caused by 3 different organisms, all of which cause anaemia. Generally, there is severe disease with animals showing depression, weakness, jaundice, fever and staggering. Death can occur in less than 2 days.

Disease caused by Babesia organisms is usually associated with high fever (frequently over 40°C), and there may be red (blood-stained) urine. Fever is not a consistent finding in disease caused by Anaplasma organisms and the urine may be dark yellow to dark brown. Diagnosis is confirmed by examination of tail tip blood smears. If you see any of these symptoms, contact your veterinarian.

Control ticks and monitor stock

Returning displaced stock

Dip all stock before or after they return to the property and keep them under close observation (preferably daily) for at least 3 weeks, as they may be incubating babesiosis during this period. Anaplasmosis can incubate for up to 60 days, so frequent observation (at least twice each week) should continue after the initial intensive monitoring.

Dipping stock

Where properties still have charged dips, strategic dipping can be employed to knock down tick populations. Dips that have been affected by floodwater may require recharging to bring them to the correct strength. Where dips are no longer charged, pour-on or injectable preparations can be used to control ticks. In either case, pay attention to sale schedules and withholding periods, and select appropriate chemicals.

Immunity to tick fever

In unvaccinated herds, be particularly vigilant if tick numbers have been low over previous years, as animals may not have been sufficiently exposed to ticks to acquire immunity. Even with moderate numbers of ticks, it is possible that an animal hasn't been exposed to tick fever organisms.

Be sure to regularly monitor stock. If necessary, implement a vaccination program to provide stock with sufficient immunity. You can contact the Tick Fever Centre by phoning our Customer Service Centre to discuss vaccination issues and order vaccine.

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