Chicken Scents Deters Malaria Mosquitoes

墨尔本PTE素材——Chicken scents deters Malaria mosquitoes

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这段音频讲的内容，是关于对抗疟疾。其中提到了两个对付mosquitoes (蚊子)的low-tech tactics(策略)——insecticides(杀虫剂)和bed nets(蚊帐)。

但是问题还远远没有解决——一是因为蚊子也开始对于杀虫剂有了抗药性，二是因为除了蚊子之外，还有其他的生物会传播这个疾病。

之后的音频内容，大致集中在Chicken 和Mosquitoes上。小编也是第一次听说，原来mosquitoes都不喜欢Chicken？会本能的避开？音频的最后，那位生态学者Ignell, 还开了个小玩笑: “We can actually reduce the number of mosquitoes indoors by just using a chicken. So that’s probably the cheapest option.”

澳大利亚语言学院整理的墨尔本PTE素材库，旨在帮助各位PTE的烤鸭们在平时练习、复习备考的阶段，除了一些官方的练习题之外，还能有不少的素材可以练习听力、阅读、口语、写作，不同PTE的题型，例如re-tell lecture，例如summarize spoken test 都是各位考生们比较纠结的难点题型。通过这大量的素材练习，大家在考场就能做到熟练作答，正常的发挥比什么都重要！

这篇报道是练习Re-tell Lecture的好素材，大家都来试试看，你能不能Re-tell这篇视频的大意吧！

这篇音频的Full transcript大家可以在上面找到哦~

有任何不认识的单词，请勤快的查阅起来吧！

Full Transcript

In Africa’s battle against malaria, two low-tech tactics—insecticides and bed nets—have done a decent job killing off mosquitoes. “But it’s mainly one species that’s been affected. That’s a species called Anopheles gambiae, often refer to as the African malaria mosquito.” Rickard Ignell, a chemical ecologist at the Swedish University of Agricultural Sciences.

He says, despite that success, the problem is far from solved. For one, mosquitoes are developing resistance to insecticides. And two, there are many other species that can spread the disease. Including one that’s common in the horn of Africa: Anopheles arabiensis.

Unlike the pickier Anopheles gambiae, its palate is wide-ranging. Arabiensis sucks the blood of cattle, sheep, goats. But… not chickens. “Chickens like mosquitoes. So they’ll actively feed on mosquitoes and other insects. So avoiding chickens could be a way of surviving, and evolving a way of smelling the chickens could be an early warning system for them.”

And it turns out, that aversion to chickens can be used against the insects. Ignell and his colleagues isolated chemical compounds from chicken feathers, and dispensed them next to a human sleeping under a bed net—a human lure. And they found that fewer mosquitoes came round for a snack, due to the repellent chemicals. The findings appear in the Malaria Journal. [Kassahun T. Jaleta et al., Chicken volatiles repel host-seeking malaria mosquitoes]

Ignell says this chicken cologne won’t be immediately available. “Ideally the world would be like that, that we can actually bottle it up and send it off and they don’t have to pay anything. But that’s not the case usually.” Luckily, there’s an equally effective substitute. “We can actually reduce the number of mosquitoes indoors by just using a chicken. So that’s probably the cheapest option.”

—Christopher Intagliata

(Source: http://www.scientificamerican.com/podcast/episode/chicken-scent-deters-malaria-mosquitoes/)