WAAVP guideline for ticks on ruminants

The World Association for the Advancement of Veterinary Parasitology (WAAVP) is a not-for-profit organisation for scientists who study the parasites of non-human animals. The guidelines, developed by the international expert working groups of the WAAVP, assist in the international harmonisation of standards and procedures for the evaluation of veterinary parasiticides. The WAAVP guidelines for evaluating the efficacy of ectoparasiticides on ruminants aim to standardise the minimum set of data that should be submitted to demonstrate the efficacy of new ectoparasiticides for use on or in ruminants.

The APVMA has adopted the WAAVP guidelines for evaluating the efficacy of ectoparasiticides on ruminants to assist registration holders in the conduct of regulatory trials. The APVMA notes that in some instances the WAAVP guidelines advise consultation with the regulator. We also recognise that because of Australia’s unique environmental and geographic parameters, parasite burdens and their population dynamics, farm management practices and animal breeds, there are some differences between the WAAVP guidelines and the APVMA’s recommendations for efficacy trials for products to be registered in Australia. Therefore, applicants should conduct efficacy trials within Australia under typical farm management practices covering relevant geographical regions and the following additional guidance is provided to assist you in conducting these trials. If you follow this additional guidance, your data should generally be sufficient for the APVMA to assess its confidence in the product’s efficacy given Australia’s unique conditions.

This preamble refers to the following World Association for the Advancement of Veterinary Parasitology (WAAVP) guideline: Holdsworth, PA, Kemp, D, Green, P, Peter, RJ, De Bruin, C, Jonsson, NN, Letonja, T, Rehbein, S & Vercruysse, J 2006, ‘World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines for evaluating the efficacy of acaricides against ticks on ruminants’, Veterinary Parasitology, vol. 136, pp. 29–43.

1. Tick species

Rhipicephalus (Boophilus) microplus is the most important cattle tick in Australia, although Haemaphysalis longicornis, Ixodes holocyclus and Rhipicephalus sanguineus also occur. You should use Rhipicephalus microplus as the target parasite species in your efficacy studies, as well as the other parasite species (e.g. Ixodes holocyclus) if you propose to claim efficacy against such parasites. If you make claims against specific resistant strains of cattle ticks, you should also demonstrate efficacy against those strains.

2. Animals

The World Association for the Advancement of Veterinary Parasitology guidelines are silent on which cattle breed should be used in these studies. The APVMA prefers that you use Bos taurus cattle which are naturally less resistant to cattle tick infestation than Bos indicus cattle.

3. Field trials

The World Association for the Advancement of Veterinary Parasitology guidelines recommend that you include at least two geographic locations in the overall study plan, with at least two study sites in each geographic location.

As additional guidance, the APVMA recommends the number, location and timing of field trials for Rhipicephalus microplus set out in Table 1.

Table 1: Number, location and timing of field trials for Rhipicephalus microplus
Region Number of trials Area Timing of trials
South East Queensland 2 Tick-infested area from Gympie to New South Wales border You should conduct trials between October and December
Central Queensland 2 Gympie north to Rockhampton You should conduct trials between September and December
Tropical Queensland 2 from Rockhampton north You should conduct trials from August to November or post–wet season from March to June

For Ixodes holocyclus, the WAAVP guidelines recommend two field trials in each geographic region. The two recommended geographic regions in Australia are coastal New South Wales and coastal Queensland.

4. Acaricides for cleansing tick-infested cattle

Given the importance of maintaining tick-free areas in Australia, if products claim efficacy for cleansing tick-infested cattle before cattle are introduced into a tick-infested area, then multiple treatments, commonly within a period of seven days, are used to ensure that cattle from infested or quarantined areas can be moved to tick-free country. Before moving these cattle, they are inspected by relevant authorities to ensure that there are no signs of tick life.

If you seek a claim for the cleansing of tick-infested cattle, you should conduct multiple treatments of infected cattle according to current movement control requirements and carry out efficacy assessments. However, examinations to support such a claim should include not only records of adult ticks collected or counted, but also detailed observations of the presence of other tick stages on the animals after they have been treated.

5. Rainfastness

The World Association for the Advancement of Veterinary Parasitology guidelines address rainfastness generally: ‘Where artificial rainfall is used to test the efficacy of a topically applied test product before or after heavy rain, the method of wetting used and the equivalent in terms of natural rainfall should be stated (for example, artificial rain applied by inverted sprinklers, equivalent to a rainfall of 20 millimetres in a storm lasting 30 minutes). The time of animal wetting before or after test product application should be recorded (for example 0, 2 hours, etc.).’

For trials conducted for cattle tick, the APVMA suggests as a guide that animals be subjected to the equivalent of 12.5 millimetres of rainfall over a 10-minute period.

6. Wool or hide damage

Given the importance of the wool and cattle by-product industries to Australian commerce, it is recommended that you collect and submit data on wool staining or damage, hide or skin damage, or damage to animal products.

To protect your privacy, please do not include contact information in your feedback. If you would like a response, please contact us.