Bioassays for acaricide resistance in ticks
Acaricide resistance monitoring
Testing for acaricide resistance in cattle ticks is crucial for implementing effective resistance management strategies. Multiple standardised methods have been developed and refined over the past decades to help researchers and veterinary professionals detect and monitor resistance patterns.
Established FAO-Recommended Methods
Larval Packet Test (LPT). The LPT has served as the primary method for identifying acaricide resistance since its introduction over 60 years ago and has proven invaluable for detecting resistance against susceptible laboratory reference strains. LPT tests are now commercially available here to assess resistance to a range of acaricidal compounds and classes.
Resistance Intensity Test (RIT).
We have introduced the RIT, a modified version of the LPT, adopting the resistance-intensity protocol from the latest WHO guidelines for resistance detection in malaria mosquito vectors. This protocol uses 1×, 5×, and 10× concentrations to reveal low, moderate, and high levels of resistance.
Innovative Rapid Testing Solutions
RaTexT® – Rapid Tick Exposure Test.
In response to the FAO expert consultation's recommendation for rapid pen-side diagnostic tests, the Rapid Tick Exposure Test (RaTexT®) was developed as a breakthrough solution.
This novel method uses partly engorged adult ticks exposed to a specially designed acaricide-impregnated matrix, delivering rapid pen-side results that differentiate between genuine tick resistance and malpractice in chemical tick control.
RaTexT® has been successfully validated in multiple studies:
1. Correctly identified both susceptible and deltamethrin-resistant Rhipicephalus microplus ticks from reference laboratory colonies and field strains in Brazil.
2. Effectively differentiated between permethrin-resistant and susceptible laboratory ticks of Rhipicephalus sanguineus.
Comprehensive Testing Portfolio.
Our bioassays support both traditional laboratory methods and innovative rapid testing approaches, enabling researchers to select the most appropriate methodology.