牛蜱和水牛蝇是澳大利亚红肉行业经济损失最严重的两类地方性虫害，二者合计造成3亿澳元经济损失，澳大利亚北部受害尤为突出。

已有报告显示水牛蝇持续向南扩散，同时害虫对现有防控药剂抗药性不断增强，如不采取干预措施，经济损失还将继续扩大。

澳大利亚肉类及畜牧业协会（MLA）资助相关研究，研发可同时防治两种害虫的新型杀虫剂，最大限度降低对蜜蜂、蜣螂等益虫的伤害风险。

悉尼大学乔尔·麦凯教授及其团队借鉴人类医药研发的前沿技术开展杀虫剂研发。

“药物研发的原理是找到引发危害的特定蛋白，再设计一种分子，使其构型恰好嵌入蛋白空腔，从而抑制蛋白活性，就像一把尺寸精准的扳手卡住运转部件。”乔尔表示。

“蜱虫体内有成千上万种功能各异的蛋白质。我们选定蜱虫生存必需的一种蛋白作为靶点，目前正在设计分子来抑制该蛋白活性。”

这项为期五年的项目将对约20万种分子开展试验，对潜力最优的分子进行精细优化，使其匹配牛蜱靶标蛋白。

“与此同时，我们会评估候选分子是否会抑制蜣螂、蜜蜂体内同源蛋白的活性。”他说道。

“只有能够选择性抑制牛蜱蛋白的分子，我们才会继续推进后续研究。”

这套研发流程同样适用于水牛蝇的防治攻关。

“多数杀虫剂面临一个难题：牛蜱和蜣螂的靶标蛋白结构相近，很难找到只对蜱虫起效的分子。”乔尔介绍。

“这就是很多杀虫剂属于广谱药剂，不具备选择性的原因。

我们选取的靶标蛋白，在各类昆虫、蜱虫等生物身上存在细微差异，这让我们有机会筛选出只针对有害虫害起效的分子。”

浇泼剂、药浴药剂、喷雾以及杀虫耳标，都是防控牛蜱和水牛蝇危害的常用手段。

出于健康安全方面的考量，广泛使用的杀虫剂二嗪磷已于2025年9月逐步停用，造成针对这两类害虫的药剂供给缺口。

项目完成后，乔尔及其团队希望为一套通用研发思路完成概念验证，用于开发更安全、更环保的杀虫剂。

“我们也在测试这套技术，将其应用到其他农业乃至医药领域，比如在不伤害益虫的前提下防治瓦螨和疟蚊，”乔尔说道。

“对于研发出药效强劲、安全且具备靶向选择性的杀虫剂，我们满怀期待。”

消息来源：MLA

Cattle tick and buffalo fly have been identified as the two highest-cost endemic disease issues for the Australian red meat industry – combined, they’re a $300 million problem, particularly in northern Australia.

With reports of the buffalo fly spreading further south and rising resistance to current controls, the cost is likely to grow without intervention.

MLA-supported research is underway to develop new pesticides to combat both pests, while minimising the risk for beneficial insects such as bees and dung beetles.

Professor Joel Mackay of The University of Sydney and his team are developing the pesticides using the same cutting-edge strategies applied in human pharmaceutical development.

“The principle behind human drug discovery is to identify the individual protein which is causing the issue and then inhibit its activity by developing a molecule with a shape that is sculpted to wedge into a cavity in the protein – a precisely shaped spanner in the works,” Joel said.

“A tick has thousands of different proteins that do many different jobs. We have chosen as our target a protein that is essential for the tick’s survival and we are now working on the design of a molecule to inhibit its activity.”

During the five-year project, around 200,000 molecules will be trialled, and the most promising ones will be carefully honed to fit into this cattle tick protein.

“At the same time, we will be assessing whether these candidate molecules also inhibit the activity of the corresponding protein in dung beetles and honeybees,” he said.

“We will be advancing with the molecules that selectively inhibit the cattle tick protein.”

The same process will be used to target the buffalo fly.

“The issue with most insecticides is that the protein that they target has a similar shape in the cattle tick and dung beetle have a similar shape, so it’s difficult to find a molecule that will only impact the tick,” Joel said.

“That’s why a lot of insecticides are broad spectrum, rather than selective.

“Our protein target is subtly different between different types of insects, ticks and so on, meaning that we have the opportunity to find molecules that are selective for the bad guys”.

Bringing more control to market

Pour-ons, dips, sprays and insecticidal ear tags are all commonly used to help combat the impact of cattle ticks and buffalo flies.

In September 2025, the widely-used insecticide ‘Diazinon’ was phased out due to health and safety concerns, leaving a gap in insecticides for both pests.

Following the project’s conclusion, Joel and his team hope to provide a proof-of-concept for a generic approach to the development of safer and more environmentally friendly insecticides.

“We’re also trialling this approach to assist in other agricultural industries – and in medicine, including suppressing Varroa mite and the Malaria mosquito without harming other, beneficial insects,” Joel said.

“We’re really excited about the prospect of making a pesticide that is not only potent, but safe and selective.”

Source：MLA