Trembling tick knees for pesticide detection
A new method could spare some laboratory animals used as guinea pigs future suffering: Swiss researchers believe they will soon be able to routinely test the effectiveness of pesticides on ticks.
The researchers at the University of Neuchâtel used a trick to use Ixoedes ricinus ticks as sensors for various insect venoms. To do this, they suggested to the bloodsuckers a natural cowhide ambience made of a skin-like silicone membrane that stretches over bowls of cattle blood and from which even a few artificial hairs sprout.
The ticks sucked blood through the membrane and even laid eggs, report the researchers from Neuchâtel. In their experimental approach, the scientists added the pesticides to be tested to the blood and then measured the knee tremors of the sucking arthropods – a reliable and early indicator of the effects of toxins on the central nervous system.
Previously investigations of this kind were not feasible. More than 10,000 experimental animals are currently used each year to test anti-tick chemicals. Such experiments remain necessary because ticks – important transmitters of various pathogens in humans and animals – quickly become resistant to pesticides. (bf)