How and when to treat other ticks
Controlling bush and paralysis ticks is difficult because:
- They are a multi-host tick and only on cattle for about 1 week at a time.
- They can survive for up to 9 months on the ground without a host.
- They can also infect native animals (i.e. reservoir hosts).
- Current spray chemicals are short acting and are slow and labour intensive to apply.
- Paralysis tick peak activity coincides with normal calving time.
Currently the only chemicals registered for controlling bush ticks and paralysis ticks are for sprays or dips. There is one ear tag product (Y-TEX PYthon tags) which can aid in the control of paralysis ticks. Actives registered for use against bush and paralysis ticks fall within the synthetic pyrethroid, organophosphate and amitraz chemical groups. Currently none of the available pour on cattle tick control products are registered for bush or paralysis tick control. Sprays may need to be used every 10 days to reduce tick numbers.
Disadvantages of using sprays and dips, include:
- Slow and labour intensive to apply.
- Large herds need special facilities such as spray races or dips.
- Dipping is effective but the infrastructure is not available in many areas.
- For sprays to work effectively, cattle must be saturated all over.
- High workplace health and safety risks for operators due to physical and chemical handling.
- Relatively short length of action of chemical actives.
Y-TEX PYthon ear tags are registered for aiding control of paralysis ticks and have a label claim of up to 42 days protection. They can be used in calves from 1 day old.
Integrated tick control
There are other steps that can be taken to help minimise tick problems, rather than relying only on chemical control. With paralysis and bush ticks, the major tick reservoir is out in the paddock and not on the cattle. Things you can do to minimise the risk include:
- Keep pastures ‘open’ by mulching or slashing them.
- Avoid having a heavy layer of mulch or dried grass, such as setaria or blady grass, because it provides an ideal environment for ticks to survive in.
- Clean out scrubby gullies of lantana where possible.
- Judicious use of burning, keeping in mind the long term impact of burning on desired pasture species and environmental effects.
- Calve earlier in the year so that calves are older before the tick population builds up.
- Calve in the cleanest paddocks and keep cows and calves there for 8–10 weeks after calving.
- Use older, resistant cattle to ‘sweep’ up ticks before putting more susceptible cows and calves into an unstocked, low burden paddock.
- Consider Bos indicus cross cattle in areas with severe tick problems – these breeds are more resistant to ticks.
- Treat early in the season when tick numbers start to build up, rather than waiting for ticks to reach plague proportions.
Figure 1. Cattle grazing in scrubby pastures may be exposed to more native ticks than those on open pastures. Image courtesy of Diane Ouwerkerk
Figure 2. Mulching or slashing pastures to keep them ‘open’ can reduce exposure of cattle to native ticks. Image courtesy of Queensland Department of Agriculture and Fisheries Fitzroy Beef Extension team.