The thousands of test animals currently required to evaluate new pesticides could be replaced by tricking ticks into setting up home on a faux cow hide, reports Jennifer Rohn for Chemistry & Industry, the magazine of the SCI.
The hide, recently developed by scientists in Switzerland, consists of a skin-like silicone membrane, complete with hair that rests over a layer of cow blood. The insects are so comfortable with the faux-cow that they set up home, copulated and laid eggs.
But it is knee trembling of a different kind that researchers measure to evaluate the early signs of pesticide toxicity. Researchers use the leg tremblings of the tick (Ioxedes ricinus) to observe the early stages of central nervous system damage, something that is not possible using live animals. Thomas Kröber and Patrick Guerin at the University of Neuchâtel confirmed the effectiveness of the system by coating the membrane with the chemical firponil, and then measuring central nerve system damage (leg trembling) and measuring tick mortality (Pest Management Science DOI:10.1002/ps.1293).
Vicky Robinson, chief executive of the National Centre for the Replacement, Refinement and Reduction of Animals in Research, said: This research takes a simple idea and applies it to great effect, resulting in a potentially significant impact on animal use. Most importantly, it demonstrates that finding ways to reduce the use of animals in research and testing is as much about improving the science as it is about considering the welfare of animals.’
More than 10,000 animals are used every year to test new tick-fighting chemicals, a figure that is likely to increase with the introduction of REACH, the EU new chemicals legislation, next year. Pesticides targeting ticks are constantly being updated and tested, because pests develop resistance so quickly. Ticks transmit several serious diseases to both animals and humans, including Lyme disease.
