Dip

• Most widely used for tick control, but also affects other external parasites
• It is a legal requirement to treat cattle being moved from known cattle tick areas to tick free zones.
• Ensure animals are completely wetted as they swim through the dip.
• Experienced, careful management is important for effective application.
• Knowing the volume of the dip is essential to mix the correct concentration.
• Follow label instructions and ensure appropriate personal protective equipment is used.

Resistance

A parasite population can develop resistance to a chemical through:

• repeated use of the same active.
• repeated overuse of a chemical (unnecessary treatments).
• wide-spread under-dosing of a chemical (e.g. under-estimating the weight of the animals being treated, poor application technique, uncalibrated dosing equipment).
• unintentionally exposing non-target parasites to chemicals (e.g. products to treat tick or lice can also affect worms).

What is resistance?

Pros

• On contact kill provides instant relief.
• Complete coverage of skin and hair with the chemical treatment.

Cons

• Requires significant infrastructure and training.
• Chemical concentration of dipping fluid must be maintained.
• Ineffective against ticks that are in a moult stage of their lifecycle.

Safety

• High risk of inadvertent chemical exposure. Dipping requires an excellent working knowledge and experience with the dipping process. Knowledge and training in safe chemical use is necessary for safety of both animals and workers when operating the dip.

Everyone working in the rural industry has a ‘duty of care’; a legal obligation to provide a safe workplace for everyone on the property.

Other information

How it works

The chemical is carried by the dipping fluid and deposited onto the skin binding on the hair of cattle as they are submerged and swim through the dip (Figure 1). Dip chemicals represent an on-contact kill but do not offer ongoing repellent for the same length of time as other chemicals do. Complete wetting of the animal gives complete skin/hair coverage with the chemical. Incomplete wetting leaves untreated areas where parasites can survive to re-establish the infestation when the chemical wears off.

Pesticide is carried by the dipping fluid and deposited onto the skin of cattle as they traverse (swim) through the dip (Figure 1). Complete wetting of the animal gives complete skin coverage with pesticide. Incomplete wetting leaves untreated areas where parasites can survive to re-establish the infestation when the pesticide wears off.

Infrastructure

Dipping infrastructure or facilities are usually permanent structures, frequently built on large cattle farms, official cattle tick clearing facilities and commercial facilities such as saleyards. They are generally unavailable on smaller farms due to the cost of the facility and maintenance of the chemical.

Dips are built to specifications that ensure full submersion of the animal including its head and ears.

A working understanding and experience in management of the dipping process is necessary for correct and safe application of chemical to animals.

Mandatory dipping

Treatment for cattle tick (Rhipicephalus australis) is mandatory in preparation for movement of cattle into tick free areas. Western Australia, Northern Territory and Queensland have mandatory requirements to prevent the introduction of cattle tick from known tick infested areas to tick free areas. Certification of the dipping procedure for cattle movement across state borders or into tick free areas is required to be done in registered accredited premises with oversight by an inspector or accredited certifier.

In Queensland, movements of cattle into cattle tick free areas can also include on property clearance using an accredited certifier.

Dip Stripping

Some compounds used for dipping are subject to ‘stripping’. This is when the dipping chemical is removed or ‘stripped’ from the dip at a faster rate than dip wash, leaving a lower concentration of active compound to the volume of water.

Labels for products that strip include instructions for reinforcement (adjusting the dip concentration with the addition of a concentrated chemical) and replenishment (topping up the dip with more chemical at the starting concentration) to maintain adequate concentrations of pesticide in the dip wash. It is important that these terms are understood and that the label directions are followed.

Figure 1 Cattle dip. Image courtesy of Scott Bauer Wikimedia CC

Management instructions

Detailed information on management of dipping is important to successful application of pesticide via this method. Further information is available in this NT Agnote: Management of a Plunge Cattle Dip.