Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly, 243122, U.P., India.
ICAR-Directorate of Medicinal and Aromatic Plants Research, Boriavi, Anand, 387310, Gujarat, India.
Ticks Tick Borne Dis. 2021 May;12(3):101655. doi: 10.1016/j.ttbdis.2021.101655. Epub 2021 Jan 19.
Animal production has a key role in global economic development and food security. Ticks, specifically Rhipicephalus microplus cause substantial economic and health impacts on more than eighty percent of the world cattle population. Though synthetic acaricides play a major role in tick management, their injudicious usage has caused environmental pollution and also promote the establishment of multi-acaricide resistant tick populations which is a matter of great concern. To provide an effective tool for controlling these resistant ticks, the present work was aimed to develop safe and inexpensive antitick natural formulations. Our bioprospection studies of Ageratum conyzoides plant established it as a species potentially having strong acaricidal activity due to the presence of potent acaricidal phyto-chemicals. To develop a suitable antitick natural formulation, 41 samples/fractions/formulations were prepared from the dry powder of the whole aerial part of the A. conyzoides plant using different techniques and delivery matrices. The strongest antitick effect was recorded for formulation ACF6, which demonstrated 87 ± 6% mean mortality with 57 % inhibition of oviposition in treated female ticks. Ticks treated with the ACF6 formulation showed a significant (p < 0.001) reduction in cuticular protein (1.238 ± 0.01 mg/mL) as compared to control ticks (2.928 ± 0.01 mg/mL) but no significant difference in chitin content of treated ticks and control ticks was observed. The formulation was found safe in a rat model as no significant differences in biochemical and haematological parameters among treated and control rats were noted. Histopathological studies indicated no sign of hepatocellular necrosis and no significant changes in the weights of liver and spleen was recorded. The overall in vivo efficacy of the formulation was 85 % for experimentally infested cattle with direct mortality of more than 80 % within 96 h post-application. The lethal effect of the formulation was in the form of drying and dead ticks 1-2 d after application. The developed formulation has the potential to be adopted as an alternative tick control measure in an ecofriendly manner.
动物生产在全球经济发展和粮食安全方面发挥着关键作用。蜱虫，特别是 Rhipicephalus microplus，对世界上超过 80%的牛群造成了巨大的经济和健康影响。尽管合成杀蜱剂在蜱虫管理中发挥着重要作用，但它们的不当使用造成了环境污染，并促使多杀蜱剂耐药蜱虫种群的建立，这是一个令人担忧的问题。为了提供一种有效的工具来控制这些耐药蜱虫，本工作旨在开发安全且廉价的抗蜱天然制剂。我们对 Ageratum conyzoides 植物的生物勘探研究表明，由于存在有效的杀蜱植物化学物质，该植物具有很强的杀蜱活性。为了开发合适的抗蜱天然制剂，我们使用不同的技术和输送基质从 A. conyzoides 植物的干粉末中制备了 41 个样品/馏分/制剂。制剂 ACF6 表现出最强的抗蜱效果，处理后的雌性蜱虫的平均死亡率为 87 ± 6%，产卵抑制率为 57%。与对照蜱虫（2.928 ± 0.01 mg/mL）相比，用 ACF6 制剂处理的蜱虫的表皮蛋白显著减少（1.238 ± 0.01 mg/mL），但处理蜱虫和对照蜱虫的几丁质含量没有显著差异。该制剂在大鼠模型中被发现是安全的，因为处理组和对照组大鼠的生化和血液学参数没有显著差异。组织病理学研究表明，没有肝细胞坏死的迹象，也没有记录到肝脏和脾脏重量的显著变化。该制剂在体内对实验感染的牛的总疗效为 85%，在应用后 96 小时内直接死亡率超过 80%。制剂的致死作用形式为干燥和死亡的蜱虫在应用后 1-2 天。该制剂具有作为一种替代的蜱虫控制措施的潜力，可以以环保的方式采用。
